package promptkit_test

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"math"
	"net/http"
	"net/http/httptest"
	"os"
	"path/filepath"
	"reflect"
	"strconv"
	"strings"
	"testing"
	"testing/fstest"
	"time"

	"gitea.maximumdirect.net/eric/promptkit"
)

const (
	frameworkContractRoot = "./testdata/framework"
	frameworkPromptDir    = frameworkContractRoot + "/prompts"
	frameworkProfileDir   = frameworkContractRoot + "/profiles"
	frameworkSchemaDir    = frameworkContractRoot + "/schemas"

	frameworkMarkdownSummaryPromptID  = "contract.markdown_summary"
	frameworkStructuredEventsPromptID = "contract.structured_events"
	frameworkFastProfileID            = "contract-fast"
	frameworkQualityProfileID         = "contract-quality"

	frameworkTranscriptPath = frameworkContractRoot + "/fixtures/transcript.md"
	frameworkGlossaryPath   = frameworkContractRoot + "/fixtures/glossary.yml"
)

func TestNewEngineRejectsMissingPromptDir(t *testing.T) {
	_, err := promptkit.NewEngine(promptkit.Config{ProfileDir: frameworkProfileDir})
	if !errors.Is(err, promptkit.ErrInvalidConfig) {
		t.Fatalf("expected ErrInvalidConfig, got %v", err)
	}
}

func TestNewEngineAcceptsMissingProfileDir(t *testing.T) {
	_, err := promptkit.NewEngine(promptkit.Config{PromptDir: frameworkPromptDir})
	if err != nil {
		t.Fatalf("expected missing profile dir to use built-ins, got %v", err)
	}
}

func TestPrepareWorksWithFrameworkContractCorpus(t *testing.T) {
	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  frameworkPromptDir,
		ProfileDir: frameworkProfileDir,
		SchemaDir:  frameworkSchemaDir,
	})
	if err != nil {
		t.Fatalf("construct engine from framework contract corpus: %v", err)
	}

	tests := []struct {
		name       string
		promptID   string
		profileID  string
		model      string
		structured bool
	}{
		{
			name:      "markdown summary",
			promptID:  frameworkMarkdownSummaryPromptID,
			profileID: frameworkFastProfileID,
			model:     "contract-fast-model",
		},
		{
			name:       "structured events",
			promptID:   frameworkStructuredEventsPromptID,
			profileID:  frameworkQualityProfileID,
			model:      "contract-quality-model",
			structured: true,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			prepared, err := engine.Prepare(context.Background(), promptkit.RunRequest{
				PromptID: tt.promptID,
				Inputs: map[string]promptkit.ArtifactRef{
					"transcript": promptkit.File(frameworkTranscriptPath),
					"glossary":   promptkit.File(frameworkGlossaryPath),
				},
			})
			if err != nil {
				t.Fatalf("prepare framework contract prompt: %v", err)
			}
			if prepared.PromptID != tt.promptID {
				t.Fatalf("unexpected prompt id: got %q, want %q", prepared.PromptID, tt.promptID)
			}
			if prepared.SelectedProfileID != tt.profileID {
				t.Fatalf("unexpected selected profile: got %q, want %q", prepared.SelectedProfileID, tt.profileID)
			}
			if prepared.EffectiveModelParams.Model != tt.model {
				t.Fatalf("unexpected effective model: got %q, want %q", prepared.EffectiveModelParams.Model, tt.model)
			}
			if len(prepared.Messages) != 2 {
				t.Fatalf("expected rendered messages, got %d", len(prepared.Messages))
			}
			if !strings.Contains(prepared.Messages[1].Content, "Nia labels the archive.") {
				t.Fatalf("expected relative prompt content to render the transcript, got %q", prepared.Messages[1].Content)
			}
			if prepared.InputHashes["transcript"] == "" || prepared.InputHashes["glossary"] == "" {
				t.Fatalf("expected input hashes, got %#v", prepared.InputHashes)
			}

			if !tt.structured {
				if prepared.StructuredOutput != nil {
					t.Fatalf("expected no structured output specification, got %#v", prepared.StructuredOutput)
				}
				return
			}

			if prepared.StructuredOutput == nil || prepared.StructuredOutput.JSONSchema == nil {
				t.Fatalf("expected loaded JSON Schema structured output, got %#v", prepared.StructuredOutput)
			}
			schema, ok := prepared.StructuredOutput.JSONSchema.Schema.(map[string]any)
			if !ok || schema["type"] != "object" {
				t.Fatalf("expected loaded object JSON Schema, got %#v", prepared.StructuredOutput.JSONSchema.Schema)
			}
			properties, ok := schema["properties"].(map[string]any)
			if !ok || properties["events"] == nil {
				t.Fatalf("expected loaded events schema property, got %#v", schema)
			}
		})
	}
}

func TestPrepareWorksWithInlineInputs(t *testing.T) {
	engine := newContractEngine(t)

	prepared, err := engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID: frameworkMarkdownSummaryPromptID,
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin scouts the tower.\nKara lights a lantern."),
			"glossary":   promptkit.InlineWithURI("memory://glossary.yml", "party:\n  - Rin\n  - Kara\n"),
		},
	})
	if err != nil {
		t.Fatalf("expected prepare to succeed, got %v", err)
	}
	if len(prepared.Messages) != 2 {
		t.Fatalf("expected rendered messages, got %d", len(prepared.Messages))
	}
	rendered := prepared.Messages[1].Content
	if !strings.Contains(rendered, "Rin scouts the tower.") || !strings.Contains(rendered, "party:") {
		t.Fatalf("expected inline inputs in rendered prompt, got %q", rendered)
	}
}

func TestPreparedRunJSONDoesNotExposeSecretOrTargetPresence(t *testing.T) {
	const envName = "PROMPTKIT_API_KEY"
	const secret = "public-api-test-secret"
	t.Setenv(envName, secret)

	profileDir := t.TempDir()
	writePublicProfileFileWithAPIKeyEnv(t, profileDir, "prepared-secret", "http://localhost:8000/v1", "prepared-secret-model", envName)
	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  frameworkPromptDir,
		ProfileDir: profileDir,
		SchemaDir:  frameworkSchemaDir,
	})
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}
	prepared, err := engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkStructuredEventsPromptID,
		ProfileID: "prepared-secret",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.File(frameworkTranscriptPath),
			"glossary":   promptkit.File(frameworkGlossaryPath),
		},
	})
	if err != nil {
		t.Fatalf("expected prepare to succeed, got %v", err)
	}

	payload, err := json.Marshal(prepared)
	if err != nil {
		t.Fatalf("expected prepared run to marshal, got %v", err)
	}
	out := string(payload)
	if strings.Contains(out, secret) {
		t.Fatalf("prepared run JSON leaked raw API key value: %s", out)
	}
	if !strings.Contains(out, envName) {
		t.Fatalf("prepared run JSON should retain api_key_env name, got %s", out)
	}
	for _, forbidden := range []string{"TargetPresence", "target_presence"} {
		if strings.Contains(out, forbidden) {
			t.Fatalf("prepared run JSON exposed internal target presence metadata %q: %s", forbidden, out)
		}
	}
}

func TestRunRequestFormattingRedactsDirectAPIKey(t *testing.T) {
	const (
		secret        = "run-request-api-key-sentinel"
		inputURI      = "memory://run-request-uri-sentinel"
		inputBody     = "run-request-body-sentinel"
		variableValue = "run-request-variable-sentinel"
	)
	req := promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: frameworkFastProfileID,
		APIKey:    secret,
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.InlineWithURI(inputURI, inputBody),
		},
		Vars: map[string]string{"audience": variableValue},
	}

	for _, formatted := range []string{
		req.String(),
		req.GoString(),
		fmt.Sprintf("%v", req),
		fmt.Sprintf("%+v", req),
		fmt.Sprintf("%#v", req),
	} {
		for _, privateValue := range []string{secret, inputURI, inputBody, variableValue} {
			if strings.Contains(formatted, privateValue) {
				t.Fatalf("formatted RunRequest leaked private value %q: %s", privateValue, formatted)
			}
		}
		for _, summary := range []string{
			`PromptID:"` + frameworkMarkdownSummaryPromptID + `"`,
			`ProfileID:"` + frameworkFastProfileID + `"`,
			"APIKeySet:true",
			"Inputs:1",
			"Vars:1",
		} {
			if !strings.Contains(formatted, summary) {
				t.Fatalf("formatted RunRequest omitted structural summary %q: %s", summary, formatted)
			}
		}
	}

	payload, err := json.Marshal(req)
	if err != nil {
		t.Fatalf("expected RunRequest to marshal, got %v", err)
	}
	if strings.Contains(string(payload), secret) {
		t.Fatalf("RunRequest JSON leaked API key: %s", payload)
	}
}

func TestGenerateRequestFormattingRedactsDirectAPIKey(t *testing.T) {
	const secret = "generate-request-secret"
	req := promptkit.GenerateRequest{
		Prompt: promptkit.RenderedPrompt{Messages: []promptkit.RenderedMessage{
			{Role: "user", Content: "secret prompt content"},
		}},
		Target: promptkit.ExecutionTarget{
			Model: "test-model",
			ExtraParams: map[string]any{
				"provider_option": "on",
			},
		},
		APIKey: secret,
	}

	for _, formatted := range []string{
		fmt.Sprint(req),
		fmt.Sprintf("%+v", req),
		fmt.Sprintf("%#v", req),
	} {
		if strings.Contains(formatted, secret) {
			t.Fatalf("formatted GenerateRequest leaked API key: %s", formatted)
		}
		if strings.Contains(formatted, "secret prompt content") {
			t.Fatalf("formatted GenerateRequest leaked prompt content: %s", formatted)
		}
		if !strings.Contains(formatted, "APIKeySet:true") {
			t.Fatalf("formatted GenerateRequest should indicate an API key is set, got %s", formatted)
		}
	}

	payload, err := json.Marshal(req)
	if err != nil {
		t.Fatalf("expected GenerateRequest to marshal, got %v", err)
	}
	if strings.Contains(string(payload), secret) {
		t.Fatalf("GenerateRequest JSON leaked API key: %s", payload)
	}
}

func TestEngineExecutionSettingPrecedence(t *testing.T) {
	floatPointer := func(value float64) *float64 {
		return &value
	}
	intPointer := func(value int) *int {
		return &value
	}
	stringPointer := func(value string) *string {
		return &value
	}

	defaultsProfile := executionProfileFixture{
		id:               "settings-defaults",
		endpoint:         "http://profile-defaults.test/v1",
		model:            "profile-defaults-model",
		serviceTier:      "profile-defaults-tier",
		reasoningEffort:  "profile-defaults-reasoning",
		apiKeyEnv:        "PROMPTKIT_PRECEDENCE_DEFAULTS",
		extraParamSource: "profile-defaults",
	}
	profileSettings := executionProfileFixture{
		id:               "settings-profile",
		endpoint:         "http://profile-settings.test/v1",
		model:            "profile-settings-model",
		temperature:      0.31,
		maxTokens:        311,
		topP:             0.61,
		timeoutSeconds:   71,
		serviceTier:      "profile-settings-tier",
		reasoningEffort:  "profile-settings-reasoning",
		apiKeyEnv:        "PROMPTKIT_PRECEDENCE_PROFILE",
		extraParamSource: "profile-settings",
	}
	requestProfile := executionProfileFixture{
		id:               "settings-request",
		endpoint:         "http://profile-request.test/v1",
		model:            "profile-request-model",
		temperature:      0.29,
		maxTokens:        299,
		topP:             0.59,
		timeoutSeconds:   79,
		serviceTier:      "profile-request-tier",
		reasoningEffort:  "profile-request-reasoning",
		apiKeyEnv:        "PROMPTKIT_PRECEDENCE_REQUEST_PROFILE",
		extraParamSource: "profile-request",
	}
	zeroOverrideProfile := executionProfileFixture{
		id:               "settings-zero",
		endpoint:         "http://profile-zero.test/v1",
		model:            "profile-zero-model",
		temperature:      0.43,
		maxTokens:        433,
		topP:             0.73,
		timeoutSeconds:   83,
		serviceTier:      "profile-zero-tier",
		reasoningEffort:  "profile-zero-reasoning",
		apiKeyEnv:        "PROMPTKIT_PRECEDENCE_ZERO",
		extraParamSource: "profile-zero",
	}

	requestTarget := promptkit.ExecutionTarget{
		Endpoint:        "http://request-settings.test/v1",
		Model:           "request-settings-model",
		Temperature:     0.87,
		MaxTokens:       877,
		TopP:            0.97,
		TimeoutSeconds:  177,
		ServiceTier:     "request-settings-tier",
		ReasoningEffort: "request-settings-reasoning",
		APIKeyEnv:       "PROMPTKIT_PRECEDENCE_REQUEST",
		ExtraParams:     map[string]any{"source": "request-settings"},
	}
	zeroOverrideTarget := executionTargetFromProfileFixture(zeroOverrideProfile)
	zeroOverrideTarget.Temperature = 0
	zeroOverrideTarget.MaxTokens = 0
	zeroOverrideTarget.TopP = 0
	zeroOverrideTarget.TimeoutSeconds = 0

	tests := []struct {
		name         string
		profile      executionProfileFixture
		override     *promptkit.ExecutionTargetOverride
		want         promptkit.ExecutionTarget
		wantPresence promptkit.ExecutionTargetPresence
	}{
		{
			name:    "unspecified provider controls retain framework timeout",
			profile: defaultsProfile,
			want: promptkit.ExecutionTarget{
				Endpoint:        defaultsProfile.endpoint,
				Model:           defaultsProfile.model,
				Temperature:     0,
				MaxTokens:       0,
				TopP:            0,
				TimeoutSeconds:  600,
				ServiceTier:     defaultsProfile.serviceTier,
				ReasoningEffort: defaultsProfile.reasoningEffort,
				APIKeyEnv:       defaultsProfile.apiKeyEnv,
				ExtraParams:     map[string]any{"source": defaultsProfile.extraParamSource},
			},
		},
		{
			name:    "profile settings replace framework defaults",
			profile: profileSettings,
			want:    executionTargetFromProfileFixture(profileSettings),
		},
		{
			name:    "request settings replace profile settings",
			profile: requestProfile,
			override: &promptkit.ExecutionTargetOverride{
				Endpoint:        requestTarget.Endpoint,
				Model:           requestTarget.Model,
				Temperature:     floatPointer(requestTarget.Temperature),
				MaxTokens:       intPointer(requestTarget.MaxTokens),
				TopP:            floatPointer(requestTarget.TopP),
				TimeoutSeconds:  intPointer(requestTarget.TimeoutSeconds),
				ServiceTier:     requestTarget.ServiceTier,
				ReasoningEffort: stringPointer(requestTarget.ReasoningEffort),
				APIKeyEnv:       requestTarget.APIKeyEnv,
				ExtraParams:     requestTarget.ExtraParams,
			},
			want:         requestTarget,
			wantPresence: promptkit.ExecutionTargetPresence{Temperature: true, MaxTokens: true, TopP: true, TimeoutSeconds: true},
		},
		{
			name:    "explicit request zero replaces profile settings",
			profile: zeroOverrideProfile,
			override: &promptkit.ExecutionTargetOverride{
				Temperature:    floatPointer(0),
				MaxTokens:      intPointer(0),
				TopP:           floatPointer(0),
				TimeoutSeconds: intPointer(0),
			},
			want:         zeroOverrideTarget,
			wantPresence: promptkit.ExecutionTargetPresence{Temperature: true, MaxTokens: true, TopP: true, TimeoutSeconds: true},
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			t.Setenv(tt.profile.apiKeyEnv, "set")
			if tt.override != nil && tt.override.APIKeyEnv != "" {
				t.Setenv(tt.override.APIKeyEnv, "set")
			}

			profileDir := t.TempDir()
			writeExecutionProfileFixture(t, profileDir, tt.profile)
			fake := &fakeLLMClient{response: &promptkit.GenerateResponse{Content: "ok"}}
			engine, err := promptkit.NewEngine(promptkit.Config{
				PromptDir:  frameworkPromptDir,
				ProfileDir: profileDir,
				SchemaDir:  frameworkSchemaDir,
			}, promptkit.WithLLMClient(fake))
			if err != nil {
				t.Fatalf("construct engine: %v", err)
			}

			_, err = engine.Run(context.Background(), promptkit.RunRequest{
				PromptID:  frameworkMarkdownSummaryPromptID,
				ProfileID: tt.profile.id,
				Inputs: map[string]promptkit.ArtifactRef{
					"transcript": promptkit.Inline("Nia labels the archive."),
					"glossary":   promptkit.Inline("archive: A catalogued collection."),
				},
				Execution: tt.override,
			})
			if err != nil {
				t.Fatalf("run engine: %v", err)
			}
			if len(fake.requests) != 1 {
				t.Fatalf("expected one generation request, got %d", len(fake.requests))
			}
			got := fake.requests[0]
			if !reflect.DeepEqual(got.Target, tt.want) {
				t.Fatalf("unexpected effective target:\ngot=%#v\nwant=%#v", got.Target, tt.want)
			}
			if got.TargetPresence != tt.wantPresence {
				t.Fatalf("unexpected target presence: got=%+v want=%+v", got.TargetPresence, tt.wantPresence)
			}
		})
	}

	t.Run("blank request reasoning clears profile setting", func(t *testing.T) {
		profile := executionProfileFixture{
			id:              "settings-reasoning-clear",
			endpoint:        "http://profile-reasoning.test/v1",
			model:           "profile-reasoning-model",
			reasoningEffort: "medium",
		}
		profileDir := t.TempDir()
		writeExecutionProfileFixture(t, profileDir, profile)
		engine, err := promptkit.NewEngine(promptkit.Config{
			PromptDir:  frameworkPromptDir,
			ProfileDir: profileDir,
			SchemaDir:  frameworkSchemaDir,
		})
		if err != nil {
			t.Fatalf("construct engine: %v", err)
		}

		prepared, err := engine.Prepare(context.Background(), promptkit.RunRequest{
			PromptID:  frameworkMarkdownSummaryPromptID,
			ProfileID: profile.id,
			Inputs: map[string]promptkit.ArtifactRef{
				"transcript": promptkit.Inline("Nia labels the archive."),
				"glossary":   promptkit.Inline("archive: A catalogued collection."),
			},
			Execution: &promptkit.ExecutionTargetOverride{
				ReasoningEffort: stringPointer(" \t "),
			},
		})
		if err != nil {
			t.Fatalf("prepare engine: %v", err)
		}
		if prepared.EffectiveModelParams.ReasoningEffort != "" {
			t.Fatalf("expected blank request reasoning to clear profile value, got %q", prepared.EffectiveModelParams.ReasoningEffort)
		}
	})
}

func TestRunSucceedsWithInjectedLLMClient(t *testing.T) {
	const envName = "PROMPTKIT_API_KEY"
	const secret = "run-secret-value"
	t.Setenv(envName, secret)

	fake := &fakeLLMClient{
		response: &promptkit.GenerateResponse{
			Content: "# Summary\n\nDone.",
			Usage: promptkit.TokenUsage{
				PromptTokens:     10,
				CompletionTokens: 5,
				TotalTokens:      15,
				CachedTokens:     3,
				CacheWriteTokens: 2,
			},
		},
	}
	engine := newContractEngineWithOptions(t, frameworkSchemaDir, promptkit.WithLLMClient(fake))

	result, err := engine.Run(context.Background(), promptkit.RunRequest{
		PromptID: frameworkMarkdownSummaryPromptID,
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
		Execution: &promptkit.ExecutionTargetOverride{
			APIKeyEnv: envName,
		},
	})
	if err != nil {
		t.Fatalf("expected run to succeed, got %v", err)
	}
	if result.RunID == "" {
		t.Fatalf("expected run id")
	}
	if result.RawOutput != fake.response.Content {
		t.Fatalf("unexpected raw output: %q", result.RawOutput)
	}
	if string(result.Artifact.Body) != fake.response.Content {
		t.Fatalf("unexpected artifact body: %q", string(result.Artifact.Body))
	}
	if result.Artifact.ContentType != "text/markdown" {
		t.Fatalf("unexpected artifact content type: %q", result.Artifact.ContentType)
	}
	if result.Validation.Status != promptkit.ValidationPassed || !result.Validation.IsValid {
		t.Fatalf("expected passed validation, got %+v", result.Validation)
	}
	if result.PromptID != frameworkMarkdownSummaryPromptID || result.SelectedProfileID != frameworkFastProfileID || result.ModelName != "contract-fast-model" {
		t.Fatalf("unexpected run metadata: %+v", result)
	}
	if result.Usage.TotalTokens != 15 || result.Usage.CachedTokens != 3 || result.Usage.CacheWriteTokens != 2 {
		t.Fatalf("unexpected usage: %+v", result.Usage)
	}

	payload, err := json.Marshal(result)
	if err != nil {
		t.Fatalf("expected run result to marshal, got %v", err)
	}
	if strings.Contains(string(payload), secret) {
		t.Fatalf("run result JSON leaked raw API key value: %s", payload)
	}
}

func TestEngineRunWithDirectorySourcesAndFileInputs(t *testing.T) {
	fake := &fakeLLMClient{
		response: &promptkit.GenerateResponse{
			Content: `{"events":[{"title":"Archive labelled"}]}`,
			Usage: promptkit.TokenUsage{
				PromptTokens:     42,
				CompletionTokens: 36,
				TotalTokens:      78,
			},
		},
	}
	engine := newContractEngineWithOptions(t, frameworkSchemaDir, promptkit.WithLLMClient(fake))

	result, err := engine.Run(context.Background(), promptkit.RunRequest{
		PromptID: frameworkStructuredEventsPromptID,
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.File(frameworkTranscriptPath),
			"glossary":   promptkit.File(frameworkGlossaryPath),
		},
	})
	if err != nil {
		t.Fatalf("expected run to succeed, got %v", err)
	}
	if result.PromptID != frameworkStructuredEventsPromptID || result.SelectedProfileID != frameworkQualityProfileID {
		t.Fatalf("unexpected run metadata: %+v", result)
	}
	if result.RunID == "" || result.PromptHash == "" || result.RenderedPromptHash == "" {
		t.Fatalf("expected run and prompt hashes, got %+v", result)
	}
	if result.InputHashes["transcript"] == "" || result.InputHashes["glossary"] == "" {
		t.Fatalf("expected both input hashes, got %#v", result.InputHashes)
	}
	if len(fake.requests) != 1 || fake.requests[0].StructuredOutput == nil ||
		fake.requests[0].StructuredOutput.Type != promptkit.StructuredOutputJSONSchema ||
		fake.requests[0].StructuredOutput.JSONSchema == nil ||
		fake.requests[0].StructuredOutput.JSONSchema.Schema == nil {
		t.Fatalf("expected provider JSON Schema structured output, got %+v", fake.requests)
	}
	if result.Validation.Status != promptkit.ValidationPassed || !result.Validation.IsValid || result.Validation.Mode != promptkit.ValidationJSONSchema {
		t.Fatalf("expected passed JSON Schema validation, got %+v", result.Validation)
	}
	if result.Artifact.ContentType != "application/json" {
		t.Fatalf("expected JSON artifact, got %q", result.Artifact.ContentType)
	}
	if result.RawOutput != fake.response.Content || result.Usage != fake.response.Usage {
		t.Fatalf("expected preserved output and usage, got output=%q usage=%+v", result.RawOutput, result.Usage)
	}
	if result.StartTime.IsZero() || result.EndTime.IsZero() || result.EndTime.Before(result.StartTime) || result.Duration < 0 {
		t.Fatalf("expected ordered non-zero timestamps and non-negative duration, got start=%v end=%v duration=%v", result.StartTime, result.EndTime, result.Duration)
	}
}

func TestRunPassesPreparedRequestToInjectedLLMClient(t *testing.T) {
	const directKey = "direct-injected-key"
	const directSession = "assembled-session"
	fake := &fakeLLMClient{
		response: &promptkit.GenerateResponse{Content: `{"events":[{"title":"Archive labelled"}]}`},
	}
	engine := newContractEngineWithOptions(t, frameworkSchemaDir, promptkit.WithLLMClient(fake))

	runRequest := promptkit.RunRequest{
		PromptID:  frameworkStructuredEventsPromptID,
		SessionID: "  " + directSession + "  ",
		APIKey:    directKey,
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	}
	prepared, err := engine.Prepare(context.Background(), runRequest)
	if err != nil {
		t.Fatalf("expected prepare to succeed, got %v", err)
	}
	result, err := engine.Run(context.Background(), runRequest)
	if err != nil {
		t.Fatalf("expected run to succeed, got %v", err)
	}
	if len(fake.requests) != 1 {
		t.Fatalf("expected one generate request, got %d", len(fake.requests))
	}
	req := fake.requests[0]
	if len(req.Prompt.Messages) != 2 || !strings.Contains(req.Prompt.Messages[1].Content, "Rin opens the gate.") {
		t.Fatalf("expected rendered prompt in generate request, got %+v", req.Prompt)
	}
	if prepared.SessionID != directSession ||
		req.Prompt.SessionID != directSession ||
		result.SessionID != directSession {
		t.Fatalf(
			"direct session did not propagate consistently: prepared=%q generated=%q result=%q",
			prepared.SessionID,
			req.Prompt.SessionID,
			result.SessionID,
		)
	}
	if req.StructuredOutput == nil || req.StructuredOutput.Type != promptkit.StructuredOutputJSONSchema || req.StructuredOutput.JSONSchema == nil {
		t.Fatalf("expected structured output handoff, got %+v", req.StructuredOutput)
	}
	if req.APIKey != directKey {
		t.Fatalf("expected direct key on injected generate request")
	}
	payload, err := json.Marshal(req)
	if err != nil {
		t.Fatalf("expected generate request to marshal, got %v", err)
	}
	if strings.Contains(string(payload), directKey) {
		t.Fatalf("generate request JSON leaked direct API key: %s", payload)
	}
}

func TestEngineRunPropagatesCallerCancellation(t *testing.T) {
	const synchronizationTimeout = 5 * time.Second

	started := make(chan struct{})
	transport := roundTripFunc(func(req *http.Request) (*http.Response, error) {
		close(started)
		<-req.Context().Done()
		return nil, req.Context().Err()
	})
	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  frameworkPromptDir,
		ProfileDir: frameworkProfileDir,
		SchemaDir:  frameworkSchemaDir,
		HTTPClient: &http.Client{Transport: transport},
	})
	if err != nil {
		t.Fatalf("construct engine: %v", err)
	}

	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()
	result := make(chan error, 1)
	go func() {
		_, err := engine.Run(ctx, promptkit.RunRequest{
			PromptID: frameworkMarkdownSummaryPromptID,
			Inputs: map[string]promptkit.ArtifactRef{
				"transcript": promptkit.Inline("Nia labels the archive."),
				"glossary":   promptkit.Inline("archive: A catalogued collection."),
			},
		})
		result <- err
	}()

	watchdog := time.NewTimer(synchronizationTimeout)
	defer watchdog.Stop()
	select {
	case <-started:
	case err := <-result:
		t.Fatalf("Engine.Run returned before the transport started: %v", err)
	case <-watchdog.C:
		t.Fatal("timed out waiting for the transport to start")
	}

	cancel()
	select {
	case err := <-result:
		if !errors.Is(err, promptkit.ErrLLMGenerate) {
			t.Fatalf("expected ErrLLMGenerate after caller cancellation, got %v", err)
		}
	case <-watchdog.C:
		t.Fatal("timed out waiting for Engine.Run to return after cancellation")
	}
}

func TestRunRejectsReservedExtraParamsBeforeProviderCall(t *testing.T) {
	called := false
	transport := roundTripFunc(func(*http.Request) (*http.Response, error) {
		called = true
		return nil, errors.New("provider should not be called")
	})
	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  frameworkPromptDir,
		ProfileDir: frameworkProfileDir,
		SchemaDir:  frameworkSchemaDir,
		HTTPClient: &http.Client{Transport: transport},
	})
	if err != nil {
		t.Fatalf("construct engine: %v", err)
	}

	_, err = engine.Run(context.Background(), promptkit.RunRequest{
		PromptID: frameworkMarkdownSummaryPromptID,
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Nia labels the archive."),
			"glossary":   promptkit.Inline("archive: A catalogued collection."),
		},
		Execution: &promptkit.ExecutionTargetOverride{
			ExtraParams: map[string]any{"model": "collision"},
		},
	})
	if !errors.Is(err, promptkit.ErrInvalidRequest) {
		t.Fatalf("expected ErrInvalidRequest, got %v", err)
	}
	if called {
		t.Fatal("expected reserved provider parameter to fail before the provider call")
	}
}

func TestRunUsesDirectAPIKeyWithDefaultLLMClient(t *testing.T) {
	const directKey = "direct-public-key"
	const missingEnv = "PROMPTKIT_PUBLIC_DIRECT_MISSING"
	t.Setenv(missingEnv, "")

	var gotAuth string
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		gotAuth = r.Header.Get("Authorization")
		if r.URL.Path != "/v1/chat/completions" {
			t.Errorf("unexpected path: %s", r.URL.Path)
		}
		w.Header().Set("Content-Type", "application/json")
		_, _ = w.Write([]byte(`{
  "choices": [{"message": {"role": "assistant", "content": "# Summary\n\nDone."}}],
  "usage": {"prompt_tokens": 3, "completion_tokens": 4, "total_tokens": 7}
}`))
	}))
	defer server.Close()

	profileDir := t.TempDir()
	writePublicProfileFileWithAPIKeyEnv(t, profileDir, "direct-auth", server.URL+"/v1", "test-model", missingEnv)
	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  frameworkPromptDir,
		ProfileDir: profileDir,
		SchemaDir:  frameworkSchemaDir,
	})
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	result, err := engine.Run(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "direct-auth",
		APIKey:    directKey,
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if err != nil {
		t.Fatalf("expected run with direct API key to succeed, got %v", err)
	}
	if gotAuth != "Bearer "+directKey {
		t.Fatalf("unexpected Authorization header: %q", gotAuth)
	}
	if result.Usage.TotalTokens != 7 {
		t.Fatalf("unexpected usage: %+v", result.Usage)
	}

	payload, err := json.Marshal(result)
	if err != nil {
		t.Fatalf("expected run result to marshal, got %v", err)
	}
	if strings.Contains(string(payload), directKey) {
		t.Fatalf("run result JSON leaked direct API key: %s", payload)
	}
}

func TestRunUsesResolvedBackendWithBuiltInLLMClient(t *testing.T) {
	const (
		backendID = "local-test"
		envName   = "PROMPTKIT_BACKEND_TRANSPORT_KEY"
		apiKey    = "synthetic-backend-key"
	)
	t.Setenv(envName, apiKey)

	var (
		gotAuth string
		gotBody map[string]any
	)
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		gotAuth = r.Header.Get("Authorization")
		if r.URL.Path != "/v1/chat/completions" {
			t.Errorf("unexpected path: %s", r.URL.Path)
		}
		if err := json.NewDecoder(r.Body).Decode(&gotBody); err != nil {
			t.Errorf("decode request body: %v", err)
		}
		w.Header().Set("Content-Type", "application/json")
		_, _ = w.Write([]byte(`{
  "choices": [{"message": {"role": "assistant", "content": "# Summary\n\nDone."}}],
  "usage": {"prompt_tokens": 3, "completion_tokens": 4, "total_tokens": 7}
}`))
	}))
	defer server.Close()

	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir: frameworkPromptDir,
		SchemaDir: frameworkSchemaDir,
	},
		promptkit.WithBackend(promptkit.Backend{
			ID:        backendID,
			Endpoint:  server.URL + "/v1",
			APIKeyEnv: envName,
			ExtraParams: map[string]any{
				"provider": "synthetic",
			},
		}),
		promptkit.WithProfiles(promptkit.Profile{
			ID:        "backend-transport",
			BackendID: backendID,
			Model:     "test-model",
		}),
	)
	if err != nil {
		t.Fatalf("construct engine: %v", err)
	}

	result, err := engine.Run(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "backend-transport",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if err != nil {
		t.Fatalf("run with resolved backend: %v", err)
	}
	if gotAuth != "Bearer "+apiKey {
		t.Fatalf("unexpected Authorization header: %q", gotAuth)
	}
	if gotBody["model"] != "test-model" || gotBody["provider"] != "synthetic" {
		t.Fatalf("backend defaults did not reach provider payload: %#v", gotBody)
	}
	for _, field := range []string{"backend_id", "api_key_env"} {
		if _, ok := gotBody[field]; ok {
			t.Fatalf("internal metadata field %q was serialized to provider payload: %#v", field, gotBody)
		}
	}
	bodyJSON, err := json.Marshal(gotBody)
	if err != nil {
		t.Fatalf("marshal captured provider payload: %v", err)
	}
	if strings.Contains(string(bodyJSON), apiKey) {
		t.Fatalf("credential value was serialized to provider payload: %s", bodyJSON)
	}
	if result.SelectedBackendID != backendID ||
		result.EffectiveModelParams.Endpoint != server.URL+"/v1" ||
		result.EffectiveModelParams.APIKeyEnv != envName {
		t.Fatalf("unexpected resolved backend metadata: %+v", result)
	}
}

func TestPrepareDirectAPIKeyBypassesMissingEnvWithoutLeakingOrHashing(t *testing.T) {
	const missingEnv = "PROMPTKIT_PUBLIC_PREPARE_MISSING"
	const firstKey = "first-direct-key"
	const secondKey = "second-direct-key"
	t.Setenv(missingEnv, "")

	profileDir := t.TempDir()
	writePublicProfileFileWithAPIKeyEnv(t, profileDir, "direct-prepare", "http://localhost:8000/v1", "test-model", missingEnv)
	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  frameworkPromptDir,
		ProfileDir: profileDir,
		SchemaDir:  frameworkSchemaDir,
	})
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	baseReq := promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "direct-prepare",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	}
	firstReq := baseReq
	firstReq.APIKey = firstKey
	firstPrepared, err := engine.Prepare(context.Background(), firstReq)
	if err != nil {
		t.Fatalf("expected prepare with direct API key to succeed, got %v", err)
	}
	secondReq := baseReq
	secondReq.APIKey = secondKey
	secondPrepared, err := engine.Prepare(context.Background(), secondReq)
	if err != nil {
		t.Fatalf("expected prepare with alternate direct API key to succeed, got %v", err)
	}

	if firstPrepared.PromptHash != secondPrepared.PromptHash {
		t.Fatalf("direct API keys changed prompt hash: %q vs %q", firstPrepared.PromptHash, secondPrepared.PromptHash)
	}
	if firstPrepared.RenderedPromptHash != secondPrepared.RenderedPromptHash {
		t.Fatalf("direct API keys changed rendered prompt hash: %q vs %q", firstPrepared.RenderedPromptHash, secondPrepared.RenderedPromptHash)
	}

	payload, err := json.Marshal(firstPrepared)
	if err != nil {
		t.Fatalf("expected prepared run to marshal, got %v", err)
	}
	if strings.Contains(string(payload), firstKey) {
		t.Fatalf("prepared run JSON leaked direct API key: %s", payload)
	}
}

func TestMissingCredentialsFailClearlyWhenProfileRequiresAuth(t *testing.T) {
	const missingEnv = "PROMPTKIT_PUBLIC_AUTH_MISSING"
	t.Setenv(missingEnv, "")

	profileDir := t.TempDir()
	writePublicProfileFileWithAPIKeyEnv(t, profileDir, "requires-auth", "http://localhost:8000/v1", "test-model", missingEnv)
	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  frameworkPromptDir,
		ProfileDir: profileDir,
		SchemaDir:  frameworkSchemaDir,
	})
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	_, err = engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "requires-auth",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if !errors.Is(err, promptkit.ErrInvalidRequest) {
		t.Fatalf("expected invalid request for missing credentials, got %v", err)
	}
	if !errors.Is(err, promptkit.ErrAPIKeyEnvMissing) {
		t.Fatalf("expected missing credential environment error, got %v", err)
	}
	if err == nil || !strings.Contains(err.Error(), missingEnv) {
		t.Fatalf("expected missing env name in error, got %v", err)
	}
}

func TestWithArtifactReaderRejectsNilReader(t *testing.T) {
	_, err := promptkit.NewEngine(contractConfig(frameworkSchemaDir), promptkit.WithArtifactReader(nil))
	if !errors.Is(err, promptkit.ErrInvalidConfig) {
		t.Fatalf("expected ErrInvalidConfig, got %v", err)
	}
}

func TestArtifactReaderReceivesPublicReferenceAndPreparesArtifact(t *testing.T) {
	reader := &recordingArtifactReader{
		artifact: &promptkit.Artifact{
			ContentType: "text/plain",
			Body:        []byte("Reader-supplied transcript."),
			URI:         "reader://transcript",
			Size:        int64(len("Reader-supplied transcript.")),
			Hash:        "reader-transcript-hash",
		},
	}
	engine := newArtifactReaderEngine(t, reader)

	ref := promptkit.ArtifactRef{
		Type: promptkit.ArtifactRefInline,
		URI:  "reader://transcript",
		Body: "request body",
	}
	prepared, err := engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID: "artifact-reader",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": ref,
		},
	})
	if err != nil {
		t.Fatalf("prepare with artifact reader: %v", err)
	}
	if len(reader.refs) != 1 || !reflect.DeepEqual(reader.refs[0], ref) {
		t.Fatalf("reader received %#v, want %#v", reader.refs, ref)
	}
	if prepared.InputHashes["transcript"] != "reader-transcript-hash" {
		t.Fatalf("unexpected input hash: %#v", prepared.InputHashes)
	}
	if len(prepared.Messages) != 1 || !strings.Contains(prepared.Messages[0].Content, "Reader-supplied transcript.") {
		t.Fatalf("prepared prompt omitted reader artifact: %#v", prepared.Messages)
	}
}

func TestArtifactReaderFailuresPreserveArtifactLoadErrors(t *testing.T) {
	readerErr := errors.New("artifact reader failed")

	tests := []struct {
		name       string
		ctx        context.Context
		reader     *recordingArtifactReader
		wantNested error
	}{
		{
			name:       "reader error",
			ctx:        context.Background(),
			reader:     &recordingArtifactReader{err: readerErr},
			wantNested: readerErr,
		},
		{
			name:   "nil artifact",
			ctx:    context.Background(),
			reader: &recordingArtifactReader{},
		},
		{
			name: "reader cancellation",
			ctx:  context.Background(),
			reader: &recordingArtifactReader{read: func(context.Context, promptkit.ArtifactRef) (*promptkit.Artifact, error) {
				return nil, context.Canceled
			}},
			wantNested: context.Canceled,
		},
		{
			name:       "public reader error",
			ctx:        context.Background(),
			reader:     &recordingArtifactReader{err: promptkit.ErrInvalidRequest},
			wantNested: promptkit.ErrInvalidRequest,
		},
	}

	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			engine := newArtifactReaderEngine(t, tc.reader)
			_, err := engine.Prepare(tc.ctx, promptkit.RunRequest{
				PromptID: "artifact-reader",
				Inputs: map[string]promptkit.ArtifactRef{
					"transcript": promptkit.Inline("input"),
				},
			})
			if !errors.Is(err, promptkit.ErrArtifactLoad) {
				t.Fatalf("expected ErrArtifactLoad, got %v", err)
			}
			if tc.wantNested != nil && !errors.Is(err, tc.wantNested) {
				t.Fatalf("expected nested %v, got %v", tc.wantNested, err)
			}
		})
	}
}

func TestRunAddsLLMGenerateToCollaboratorPublicError(t *testing.T) {
	engine := newContractEngineWithOptions(t, frameworkSchemaDir,
		promptkit.WithLLMClient(&fakeLLMClient{err: promptkit.ErrArtifactLoad}),
	)

	_, err := engine.Run(context.Background(), promptkit.RunRequest{
		PromptID: frameworkMarkdownSummaryPromptID,
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if !errors.Is(err, promptkit.ErrLLMGenerate) {
		t.Fatalf("expected ErrLLMGenerate, got %v", err)
	}
	if !errors.Is(err, promptkit.ErrArtifactLoad) {
		t.Fatalf("expected preserved ErrArtifactLoad, got %v", err)
	}
}

func TestPrepareWithoutProfileMatchesSpecificPublicError(t *testing.T) {
	promptDir := t.TempDir()
	writePublicPromptFile(t, promptDir, "profile-required", "")
	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir: promptDir,
		SchemaDir: frameworkSchemaDir,
	})
	if err != nil {
		t.Fatalf("construct engine: %v", err)
	}

	_, err = engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID: "profile-required",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("input"),
		},
	})
	if !errors.Is(err, promptkit.ErrInvalidRequest) {
		t.Fatalf("expected ErrInvalidRequest, got %v", err)
	}
	if !errors.Is(err, promptkit.ErrProfileRequired) {
		t.Fatalf("expected ErrProfileRequired, got %v", err)
	}
}

func TestRunValidationFailureReturnsResult(t *testing.T) {
	fake := &fakeLLMClient{
		response: &promptkit.GenerateResponse{Content: ""},
	}
	engine := newContractEngineWithOptions(t, frameworkSchemaDir, promptkit.WithLLMClient(fake))

	result, err := engine.Run(context.Background(), promptkit.RunRequest{
		PromptID: frameworkMarkdownSummaryPromptID,
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if err != nil {
		t.Fatalf("expected validation failure as successful result, got %v", err)
	}
	if result.Validation.Status != promptkit.ValidationFailed || result.Validation.IsValid {
		t.Fatalf("expected failed validation result, got %+v", result.Validation)
	}
	if len(result.Validation.Errors) == 0 {
		t.Fatalf("expected validation errors")
	}
}

func TestPublicErrorsSupportErrorsIs(t *testing.T) {
	llmErr := errors.New("llm failed")

	tests := []struct {
		name      string
		req       promptkit.RunRequest
		client    promptkit.LLMClient
		schemaDir string
		want      error
		notWant   error
	}{
		{
			name:   "invalid request",
			req:    promptkit.RunRequest{},
			client: &fakeLLMClient{response: &promptkit.GenerateResponse{Content: "ok"}},
			want:   promptkit.ErrInvalidRequest,
		},
		{
			name:    "prompt not found",
			req:     promptkit.RunRequest{PromptID: "missing.prompt"},
			client:  &fakeLLMClient{response: &promptkit.GenerateResponse{Content: "ok"}},
			want:    promptkit.ErrPromptNotFound,
			notWant: promptkit.ErrPromptLoad,
		},
		{
			name: "profile not found",
			req: promptkit.RunRequest{
				PromptID:  frameworkMarkdownSummaryPromptID,
				ProfileID: "missing-profile",
				Inputs: map[string]promptkit.ArtifactRef{
					"transcript": promptkit.Inline("Rin opens the gate."),
				},
			},
			client:  &fakeLLMClient{response: &promptkit.GenerateResponse{Content: "ok"}},
			want:    promptkit.ErrProfileNotFound,
			notWant: promptkit.ErrProfileLoad,
		},
		{
			name: "artifact load",
			req: promptkit.RunRequest{
				PromptID: frameworkMarkdownSummaryPromptID,
				Inputs: map[string]promptkit.ArtifactRef{
					"transcript": promptkit.File(filepath.Join(t.TempDir(), "does-not-exist.md")),
				},
			},
			client: &fakeLLMClient{response: &promptkit.GenerateResponse{Content: "ok"}},
			want:   promptkit.ErrArtifactLoad,
		},
		{
			name: "prompt render",
			req: promptkit.RunRequest{
				PromptID: frameworkMarkdownSummaryPromptID,
			},
			client: &fakeLLMClient{response: &promptkit.GenerateResponse{Content: "ok"}},
			want:   promptkit.ErrPromptRender,
		},
		{
			name: "llm failure",
			req: promptkit.RunRequest{
				PromptID: frameworkMarkdownSummaryPromptID,
				Inputs: map[string]promptkit.ArtifactRef{
					"transcript": promptkit.Inline("Rin opens the gate."),
					"glossary":   promptkit.Inline("gate: A guarded passage."),
				},
			},
			client: &fakeLLMClient{err: llmErr},
			want:   promptkit.ErrLLMGenerate,
		},
		{
			name: "nil llm response",
			req: promptkit.RunRequest{
				PromptID: frameworkMarkdownSummaryPromptID,
				Inputs: map[string]promptkit.ArtifactRef{
					"transcript": promptkit.Inline("Rin opens the gate."),
					"glossary":   promptkit.Inline("gate: A guarded passage."),
				},
			},
			client: &fakeLLMClient{},
			want:   promptkit.ErrLLMGenerate,
		},
		{
			name: "validation runtime failure",
			req: promptkit.RunRequest{
				PromptID: frameworkStructuredEventsPromptID,
				Inputs: map[string]promptkit.ArtifactRef{
					"transcript": promptkit.Inline("Rin opens the gate."),
				},
			},
			client:    &fakeLLMClient{response: &promptkit.GenerateResponse{Content: `{"events":[]}`}},
			schemaDir: t.TempDir(),
			want:      promptkit.ErrValidation,
		},
	}

	t.Setenv("PROMPTKIT_API_KEY", "test-secret")
	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			schemaDir := tc.schemaDir
			if schemaDir == "" {
				schemaDir = frameworkSchemaDir
			}
			engine := newContractEngineWithOptions(t, schemaDir, promptkit.WithLLMClient(tc.client))
			_, err := engine.Run(context.Background(), tc.req)
			if !errors.Is(err, tc.want) {
				t.Fatalf("expected errors.Is(%v), got %v", tc.want, err)
			}
			if tc.notWant != nil && errors.Is(err, tc.notWant) {
				t.Fatalf("did not expect errors.Is(%v), got %v", tc.notWant, err)
			}
		})
	}
}

func TestSelectedProfileRawAPIKeyMapsToProfileLoad(t *testing.T) {
	profileDir := t.TempDir()
	if err := os.WriteFile(filepath.Join(profileDir, "raw.yaml"), []byte(`
id: raw-profile
endpoint: http://localhost:8000/v1
model: model
api_key: secret
`), 0644); err != nil {
		t.Fatal(err)
	}

	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  frameworkPromptDir,
		ProfileDir: profileDir,
		SchemaDir:  frameworkSchemaDir,
	})
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	_, err = engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "raw-profile",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if !errors.Is(err, promptkit.ErrProfileLoad) {
		t.Fatalf("expected ErrProfileLoad, got %v", err)
	}
	if errors.Is(err, promptkit.ErrPromptLoad) {
		t.Fatalf("did not expect ErrPromptLoad, got %v", err)
	}
}

func TestSelectedProfileInvalidYAMLMapsToProfileLoad(t *testing.T) {
	profileDir := t.TempDir()
	if err := os.WriteFile(filepath.Join(profileDir, "broken.yaml"), []byte(`
id: broken-profile
unknown_field: true
`), 0644); err != nil {
		t.Fatal(err)
	}

	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  frameworkPromptDir,
		ProfileDir: profileDir,
		SchemaDir:  frameworkSchemaDir,
	})
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	_, err = engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "broken-profile",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if !errors.Is(err, promptkit.ErrProfileLoad) {
		t.Fatalf("expected ErrProfileLoad, got %v", err)
	}
	if errors.Is(err, promptkit.ErrPromptLoad) {
		t.Fatalf("did not expect ErrPromptLoad, got %v", err)
	}
}

func TestPromptRepositoryReadFailureMapsToPromptLoad(t *testing.T) {
	missingPromptDir := filepath.Join(t.TempDir(), "missing-prompts")
	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  missingPromptDir,
		ProfileDir: frameworkProfileDir,
		SchemaDir:  frameworkSchemaDir,
	})
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	_, err = engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID: frameworkMarkdownSummaryPromptID,
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if !errors.Is(err, promptkit.ErrPromptLoad) {
		t.Fatalf("expected ErrPromptLoad, got %v", err)
	}
	if errors.Is(err, promptkit.ErrProfileLoad) {
		t.Fatalf("did not expect ErrProfileLoad, got %v", err)
	}
}

func TestSelectedProfileRepositoryReadFailureMapsToProfileLoad(t *testing.T) {
	missingProfileDir := filepath.Join(t.TempDir(), "missing-profiles")
	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  frameworkPromptDir,
		ProfileDir: missingProfileDir,
		SchemaDir:  frameworkSchemaDir,
	})
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	_, err = engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: frameworkFastProfileID,
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if !errors.Is(err, promptkit.ErrProfileLoad) {
		t.Fatalf("expected ErrProfileLoad, got %v", err)
	}
	if errors.Is(err, promptkit.ErrPromptLoad) {
		t.Fatalf("did not expect ErrPromptLoad, got %v", err)
	}
}

func TestPrepareUsesBuiltInProfileWithoutProfileDir(t *testing.T) {
	t.Setenv("OPENROUTER_API_KEY", "test-key")
	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir: frameworkPromptDir,
		SchemaDir: frameworkSchemaDir,
	})
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	prepared, err := engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "mistral-small-3",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if err != nil {
		t.Fatalf("expected built-in profile prepare to succeed, got %v", err)
	}
	if prepared.SelectedProfileID != "mistral-small-3" {
		t.Fatalf("unexpected selected profile: %q", prepared.SelectedProfileID)
	}
	if prepared.SelectedBackendID != promptkit.BackendOpenRouter {
		t.Fatalf("unexpected selected backend: %q", prepared.SelectedBackendID)
	}
	if prepared.EffectiveModelParams.BackendID != promptkit.BackendOpenRouter {
		t.Fatalf("unexpected effective backend: %q", prepared.EffectiveModelParams.BackendID)
	}
	if prepared.EffectiveModelParams.Endpoint != "https://openrouter.ai/api/v1" {
		t.Fatalf("unexpected built-in endpoint: %q", prepared.EffectiveModelParams.Endpoint)
	}
	if prepared.EffectiveModelParams.APIKeyEnv != "OPENROUTER_API_KEY" {
		t.Fatalf("unexpected built-in api key environment name: %q", prepared.EffectiveModelParams.APIKeyEnv)
	}
	if prepared.EffectiveModelParams.Model != "mistralai/mistral-small-3.2-24b-instruct" {
		t.Fatalf("unexpected built-in model: %q", prepared.EffectiveModelParams.Model)
	}
}

func TestPromptDefaultProfileCanUseBuiltInProfile(t *testing.T) {
	t.Setenv("OPENROUTER_API_KEY", "test-key")
	promptDir := t.TempDir()
	writePublicPromptFile(t, promptDir, "prompt.builtin.default", "mistral-small-3")

	engine, err := promptkit.NewEngine(promptkit.Config{PromptDir: promptDir})
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	prepared, err := engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID: "prompt.builtin.default",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
		},
	})
	if err != nil {
		t.Fatalf("expected built-in default profile prepare to succeed, got %v", err)
	}
	if prepared.SelectedProfileID != "mistral-small-3" {
		t.Fatalf("unexpected selected profile: %q", prepared.SelectedProfileID)
	}
}

func TestCustomProfileOverridesBuiltInProfile(t *testing.T) {
	t.Setenv("OPENROUTER_API_KEY", "test-key")
	profileDir := t.TempDir()
	writePublicProfileFile(t, profileDir, "mistral-small-3", "http://localhost:8000/v1", "custom-model")

	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  frameworkPromptDir,
		ProfileDir: profileDir,
		SchemaDir:  frameworkSchemaDir,
	})
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	prepared, err := engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "mistral-small-3",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if err != nil {
		t.Fatalf("expected custom profile prepare to succeed, got %v", err)
	}
	if prepared.EffectiveModelParams.Model != "custom-model" {
		t.Fatalf("expected custom profile to override built-in, got %q", prepared.EffectiveModelParams.Model)
	}
}

func TestMalformedCustomProfileDoesNotFallbackToBuiltIn(t *testing.T) {
	t.Setenv("OPENROUTER_API_KEY", "test-key")
	profileDir := t.TempDir()
	if err := os.WriteFile(filepath.Join(profileDir, "mistral-small-3.yml"), []byte(`
id: mistral-small-3
endpoint: http://localhost:8000/v1
model: custom-model
unexpected: true
`), 0o644); err != nil {
		t.Fatal(err)
	}

	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  frameworkPromptDir,
		ProfileDir: profileDir,
		SchemaDir:  frameworkSchemaDir,
	})
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	_, err = engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "mistral-small-3",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if !errors.Is(err, promptkit.ErrProfileLoad) {
		t.Fatalf("expected custom profile load error, got %v", err)
	}
}

func TestPrepareWorksWithPromptFSAndRelativeContentFile(t *testing.T) {
	promptFS := fstest.MapFS{
		"assets/prompts/fs-summary.yaml": &fstest.MapFile{Data: []byte(`
id: fs.summary
version: "1.0.0"
default_profile: contract-fast
inputs:
  - name: transcript
    required: true
messages:
  - role: user
    content_file: ./messages/summary.tmpl
output:
  format: text
  validation_mode: none
  repair_attempts: 0
`)},
		"assets/prompts/messages/summary.tmpl": &fstest.MapFile{Data: []byte(`Summarize {{input "transcript"}} from prompt fs.`)},
	}

	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  t.TempDir(),
		ProfileDir: frameworkProfileDir,
		SchemaDir:  frameworkSchemaDir,
	}, promptkit.WithPromptFS(promptFS, "assets/prompts"))
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	prepared, err := engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID: "fs.summary",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
		},
	})
	if err != nil {
		t.Fatalf("expected prepare to succeed, got %v", err)
	}
	if len(prepared.Messages) != 1 || !strings.Contains(prepared.Messages[0].Content, "prompt fs") {
		t.Fatalf("expected content_file body from prompt fs, got %+v", prepared.Messages)
	}
}

func TestPrepareWithPromptFSRejectsEscapedContentFile(t *testing.T) {
	promptFS := fstest.MapFS{
		"assets/prompts/fs-escape.yaml": &fstest.MapFile{Data: []byte(`
id: fs.escape
version: "1.0.0"
default_profile: contract-fast
messages:
  - role: user
    content_file: ../outside.tmpl
output:
  format: text
  validation_mode: none
  repair_attempts: 0
`)},
		"assets/outside.tmpl": &fstest.MapFile{Data: []byte(`Outside root.`)},
	}

	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  t.TempDir(),
		ProfileDir: frameworkProfileDir,
		SchemaDir:  frameworkSchemaDir,
	}, promptkit.WithPromptFS(promptFS, "assets/prompts"))
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	_, err = engine.Prepare(context.Background(), promptkit.RunRequest{PromptID: "fs.escape"})
	if !errors.Is(err, promptkit.ErrPromptLoad) {
		t.Fatalf("expected ErrPromptLoad, got %v", err)
	}
}

func TestPrepareWorksWithPromptFile(t *testing.T) {
	promptDir := t.TempDir()
	promptPath := filepath.Join(promptDir, "single.yaml")
	if err := os.WriteFile(promptPath, []byte(`
id: single.file.prompt
version: "1.0.0"
default_profile: contract-fast
inputs:
  - name: transcript
    required: true
messages:
  - role: user
    content_file: ./single.tmpl
output:
  format: text
  validation_mode: none
  repair_attempts: 0
`), 0o644); err != nil {
		t.Fatal(err)
	}
	if err := os.WriteFile(filepath.Join(promptDir, "single.tmpl"), []byte(`Summarize {{input "transcript"}} from file.`), 0o644); err != nil {
		t.Fatal(err)
	}

	engine, err := promptkit.NewEngine(promptkit.Config{
		ProfileDir: frameworkProfileDir,
		SchemaDir:  frameworkSchemaDir,
	}, promptkit.WithPromptFile(promptPath))
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	prepared, err := engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID: "single.file.prompt",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
		},
	})
	if err != nil {
		t.Fatalf("expected prepare to succeed, got %v", err)
	}
	if prepared.PromptID != "single.file.prompt" {
		t.Fatalf("unexpected prompt id: %q", prepared.PromptID)
	}
	if len(prepared.Messages) != 1 || !strings.Contains(prepared.Messages[0].Content, "from file") {
		t.Fatalf("expected content_file body from prompt file, got %+v", prepared.Messages)
	}
}

func TestPrepareWorksWithProfileFSOverBuiltIns(t *testing.T) {
	profileFS := fstest.MapFS{
		"profiles/mistral-small-3.yaml": &fstest.MapFile{Data: []byte(`
id: mistral-small-3
endpoint: http://profile-fs/v1
model: profile-fs-model
`)},
	}

	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir: frameworkPromptDir,
		SchemaDir: frameworkSchemaDir,
	}, promptkit.WithProfileFS(profileFS, "profiles"))
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	prepared, err := engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "mistral-small-3",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if err != nil {
		t.Fatalf("expected prepare to succeed, got %v", err)
	}
	if prepared.EffectiveModelParams.Model != "profile-fs-model" {
		t.Fatalf("expected profile fs to override built-in, got %q", prepared.EffectiveModelParams.Model)
	}
}

func TestPrepareWorksWithProfileFileOverBuiltIns(t *testing.T) {
	profileDir := t.TempDir()
	profilePath := filepath.Join(profileDir, "mistral-small-3.yaml")
	if err := os.WriteFile(profilePath, []byte(`
id: mistral-small-3
endpoint: http://profile-file/v1
model: profile-file-model
`), 0o644); err != nil {
		t.Fatal(err)
	}

	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir: frameworkPromptDir,
		SchemaDir: frameworkSchemaDir,
	}, promptkit.WithProfileFile(profilePath))
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	prepared, err := engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "mistral-small-3",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if err != nil {
		t.Fatalf("expected prepare to succeed, got %v", err)
	}
	if prepared.EffectiveModelParams.Model != "profile-file-model" {
		t.Fatalf("expected profile file to override built-in, got %q", prepared.EffectiveModelParams.Model)
	}
}

func TestPrepareWorksWithInMemoryProfilesWithoutProfileFiles(t *testing.T) {
	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir: frameworkPromptDir,
		SchemaDir: frameworkSchemaDir,
	}, promptkit.WithProfiles(promptkit.Profile{
		ID:       "memory-profile",
		Endpoint: "http://memory-profile/v1",
		Model:    "memory-model",
	}))
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	prepared, err := engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "memory-profile",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if err != nil {
		t.Fatalf("expected prepare to succeed, got %v", err)
	}
	if prepared.EffectiveModelParams.Model != "memory-model" {
		t.Fatalf("expected in-memory profile model, got %q", prepared.EffectiveModelParams.Model)
	}
}

func TestInMemoryProfilesOverrideBuiltInsAndProfileSources(t *testing.T) {
	profileFS := fstest.MapFS{
		"profiles/mistral-small-3.yaml": &fstest.MapFile{Data: []byte(`
id: mistral-small-3
endpoint: http://profile-fs/v1
model: profile-fs-model
`)},
	}

	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir: frameworkPromptDir,
		SchemaDir: frameworkSchemaDir,
	},
		promptkit.WithProfileFS(profileFS, "profiles"),
		promptkit.WithProfiles(promptkit.Profile{
			ID:       "mistral-small-3",
			Endpoint: "http://memory-profile/v1",
			Model:    "memory-profile-model",
		}),
	)
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	prepared, err := engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "mistral-small-3",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if err != nil {
		t.Fatalf("expected prepare to succeed, got %v", err)
	}
	if prepared.EffectiveModelParams.Model != "memory-profile-model" {
		t.Fatalf("expected in-memory profile to have highest precedence, got %q", prepared.EffectiveModelParams.Model)
	}
}

func TestWithProfilesRejectsDuplicateIDs(t *testing.T) {
	_, err := promptkit.NewEngine(promptkit.Config{PromptDir: frameworkPromptDir},
		promptkit.WithProfiles(
			promptkit.Profile{ID: "duplicate", Endpoint: "http://one/v1", Model: "one"},
			promptkit.Profile{ID: "duplicate", Endpoint: "http://two/v1", Model: "two"},
		),
	)
	if !errors.Is(err, promptkit.ErrInvalidConfig) {
		t.Fatalf("expected ErrInvalidConfig, got %v", err)
	}
}

func TestWithProfilesRejectsInvalidExecutionSettings(t *testing.T) {
	type testCase struct {
		name    string
		profile promptkit.Profile
	}
	tests := []testCase{
		{name: "non-finite temperature", profile: promptkit.Profile{Temperature: math.NaN()}},
		{name: "non-finite top p", profile: promptkit.Profile{TopP: math.Inf(-1)}},
	}
	if strconv.IntSize == 64 {
		durationLimit := int64(math.MaxInt64 / int64(time.Second))
		tests = append(tests, testCase{name: "unrepresentable timeout", profile: promptkit.Profile{TimeoutSeconds: int(durationLimit) + 1}})
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			tt.profile.ID = "invalid-settings"
			tt.profile.Endpoint = "http://example.test/v1"
			tt.profile.Model = "model"
			_, err := promptkit.NewEngine(promptkit.Config{PromptDir: frameworkPromptDir},
				promptkit.WithProfiles(tt.profile),
			)
			if !errors.Is(err, promptkit.ErrInvalidConfig) {
				t.Fatalf("expected ErrInvalidConfig, got %v", err)
			}
		})
	}
}

func TestOpenAICompatibleProfileRunsThroughNormalProfilePath(t *testing.T) {
	fake := &fakeLLMClient{response: &promptkit.GenerateResponse{Content: "ok"}}
	prof := promptkit.OpenAICompatibleProfile(promptkit.OpenAICompatibleProfileConfig{
		ID:             "template-profile",
		BackendID:      "  openrouter  ",
		Endpoint:       "http://template/v1",
		Model:          "template-model",
		APIKeyRequired: true,
		ExtraParams: map[string]any{
			"provider": "template",
		},
	})

	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir: frameworkPromptDir,
		SchemaDir: frameworkSchemaDir,
	}, promptkit.WithProfiles(prof), promptkit.WithLLMClient(fake))
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	_, err = engine.Run(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "template-profile",
		APIKey:    "template-key",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if err != nil {
		t.Fatalf("expected run to succeed, got %v", err)
	}
	if len(fake.requests) != 1 {
		t.Fatalf("expected one request, got %d", len(fake.requests))
	}
	if fake.requests[0].Target.BackendID != promptkit.BackendOpenRouter ||
		fake.requests[0].Target.Model != "template-model" ||
		fake.requests[0].APIKey != "template-key" {
		t.Fatalf("unexpected generated request: %+v", fake.requests[0])
	}
	if !reflect.DeepEqual(fake.requests[0].Target.ExtraParams, map[string]any{"provider": "template"}) {
		t.Fatalf("unexpected extra params: %#v", fake.requests[0].Target.ExtraParams)
	}
}

func TestOpenAICompatibleProfileMapsEveryField(t *testing.T) {
	extraParams := map[string]any{"provider_option": "distinct-extra-params"}
	got := promptkit.OpenAICompatibleProfile(promptkit.OpenAICompatibleProfileConfig{
		ID:              "distinct-id",
		BackendID:       "distinct-backend",
		Endpoint:        "https://distinct.example/v1",
		Model:           "distinct-model",
		APIKeyRequired:  true,
		Temperature:     0.25,
		MaxTokens:       321,
		TopP:            0.75,
		TimeoutSeconds:  43,
		ServiceTier:     "distinct-service-tier",
		ReasoningEffort: "distinct-reasoning-effort",
		ExtraParams:     extraParams,
	})
	want := promptkit.Profile{
		ID:              "distinct-id",
		BackendID:       "distinct-backend",
		Endpoint:        "https://distinct.example/v1",
		Model:           "distinct-model",
		Temperature:     0.25,
		MaxTokens:       321,
		TopP:            0.75,
		TimeoutSeconds:  43,
		ServiceTier:     "distinct-service-tier",
		ReasoningEffort: "distinct-reasoning-effort",
		APIKeyRequired:  true,
		ExtraParams:     map[string]any{"provider_option": "distinct-extra-params"},
	}
	if !reflect.DeepEqual(got, want) {
		t.Fatalf("profile mapping:\ngot  %#v\nwant %#v", got, want)
	}

	extraParams["added_after_construction"] = true
	if _, ok := got.ExtraParams["added_after_construction"]; ok {
		t.Fatal("profile retained the configuration map")
	}
}

func TestEngineRunLayersTransportAndGenerationTimeouts(t *testing.T) {
	intPointer := func(value int) *int {
		return &value
	}

	tests := []struct {
		name                   string
		configTimeout          time.Duration
		suppliedClientTimeout  time.Duration
		profileTimeoutSeconds  int
		requestTimeoutSeconds  *int
		callerTimeout          time.Duration
		wantRemainingAtRequest time.Duration
	}{
		{
			name:                   "positive supplied client cap takes precedence over config",
			configTimeout:          2 * time.Second,
			suppliedClientTimeout:  6 * time.Second,
			wantRemainingAtRequest: 6 * time.Second,
		},
		{
			name:                   "zero supplied client timeout inherits config cap",
			configTimeout:          5 * time.Second,
			wantRemainingAtRequest: 5 * time.Second,
		},
		{
			name:                   "zero configuration uses ten minute transport default",
			wantRemainingAtRequest: 10 * time.Minute,
		},
		{
			name:                   "negative configuration uses ten minute transport default",
			configTimeout:          -2 * time.Second,
			suppliedClientTimeout:  -3 * time.Second,
			wantRemainingAtRequest: 10 * time.Minute,
		},
		{
			name:                   "profile deadline is shorter than transport cap",
			suppliedClientTimeout:  6 * time.Second,
			profileTimeoutSeconds:  4,
			wantRemainingAtRequest: 4 * time.Second,
		},
		{
			name:                   "request deadline is shorter than profile and transport limits",
			suppliedClientTimeout:  6 * time.Second,
			profileTimeoutSeconds:  4,
			requestTimeoutSeconds:  intPointer(2),
			wantRemainingAtRequest: 2 * time.Second,
		},
		{
			name:                   "explicit zero removes generation deadline but retains transport cap",
			suppliedClientTimeout:  5 * time.Second,
			profileTimeoutSeconds:  2,
			requestTimeoutSeconds:  intPointer(0),
			wantRemainingAtRequest: 5 * time.Second,
		},
		{
			name:                   "framework default remains layered with shorter transport cap",
			configTimeout:          7 * time.Second,
			suppliedClientTimeout:  3 * time.Second,
			wantRemainingAtRequest: 3 * time.Second,
		},
		{
			name:                   "caller deadline remains layered with other limits",
			suppliedClientTimeout:  6 * time.Second,
			profileTimeoutSeconds:  4,
			callerTimeout:          2 * time.Second,
			wantRemainingAtRequest: 2 * time.Second,
		},
	}

	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			var (
				sawDeadline bool
				remaining   time.Duration
			)
			transport := roundTripFunc(func(req *http.Request) (*http.Response, error) {
				deadline, ok := req.Context().Deadline()
				sawDeadline = ok
				if ok {
					remaining = time.Until(deadline)
				}
				return &http.Response{
					StatusCode: http.StatusOK,
					Status:     "200 OK",
					Header:     make(http.Header),
					Body: io.NopCloser(strings.NewReader(
						`{"choices":[{"message":{"content":"ok"}}]}`,
					)),
					Request: req,
				}, nil
			})
			httpClient := &http.Client{
				Timeout:   tc.suppliedClientTimeout,
				Transport: transport,
			}
			engine, err := promptkit.NewEngine(promptkit.Config{
				PromptDir:  frameworkPromptDir,
				SchemaDir:  frameworkSchemaDir,
				Timeout:    tc.configTimeout,
				HTTPClient: httpClient,
			}, promptkit.WithProfiles(promptkit.Profile{
				ID:             "layered-timeout",
				Endpoint:       "http://timeout.test/v1",
				Model:          "timeout-model",
				TimeoutSeconds: tc.profileTimeoutSeconds,
			}))
			if err != nil {
				t.Fatalf("expected engine construction to succeed, got %v", err)
			}

			ctx := context.Background()
			cancel := func() {}
			if tc.callerTimeout > 0 {
				ctx, cancel = context.WithTimeout(ctx, tc.callerTimeout)
			}
			defer cancel()

			_, err = engine.Run(ctx, promptkit.RunRequest{
				PromptID:  frameworkMarkdownSummaryPromptID,
				ProfileID: "layered-timeout",
				Inputs: map[string]promptkit.ArtifactRef{
					"transcript": promptkit.Inline("Rin opens the gate."),
					"glossary":   promptkit.Inline("gate: A guarded passage."),
				},
				Execution: &promptkit.ExecutionTargetOverride{
					TimeoutSeconds: tc.requestTimeoutSeconds,
				},
			})
			if err != nil {
				t.Fatalf("expected run to succeed, got %v", err)
			}
			if !sawDeadline {
				t.Fatal("expected outbound request context to have a deadline")
			}

			const deadlineTolerance = 750 * time.Millisecond
			if remaining < tc.wantRemainingAtRequest-deadlineTolerance ||
				remaining > tc.wantRemainingAtRequest+50*time.Millisecond {
				t.Fatalf(
					"unexpected request deadline: remaining=%v want approximately %v",
					remaining,
					tc.wantRemainingAtRequest,
				)
			}
		})
	}
}

func TestOpenAICompatibleProfileDefersExtraParamsValidation(t *testing.T) {
	cyclic := map[string]any{}
	cyclic["self"] = cyclic

	prof := promptkit.OpenAICompatibleProfile(promptkit.OpenAICompatibleProfileConfig{
		ID:          "cyclic-template-profile",
		Endpoint:    "http://cyclic-template/v1",
		Model:       "cyclic-template-model",
		ExtraParams: cyclic,
	})

	_, err := promptkit.NewEngine(promptkit.Config{PromptDir: frameworkPromptDir},
		promptkit.WithProfiles(prof),
	)
	if !errors.Is(err, promptkit.ErrInvalidConfig) {
		t.Fatalf("expected ErrInvalidConfig, got %v", err)
	}
}

func TestOpenAICompatibleProfileNestedExtraParamsRunThroughWithProfiles(t *testing.T) {
	fake := &fakeLLMClient{response: &promptkit.GenerateResponse{Content: "ok"}}
	nested := map[string]any{
		"labels": map[string]string{"route": "primary"},
		"ids":    []int{1, 2, 3},
	}
	extraParams := map[string]any{
		"nested": nested,
	}
	prof := promptkit.OpenAICompatibleProfile(promptkit.OpenAICompatibleProfileConfig{
		ID:          "nested-template-profile",
		Endpoint:    "http://nested-template/v1",
		Model:       "nested-template-model",
		ExtraParams: extraParams,
	})
	extraParams["added"] = "mutated-after-construction"

	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir: frameworkPromptDir,
		SchemaDir: frameworkSchemaDir,
	}, promptkit.WithProfiles(prof), promptkit.WithLLMClient(fake))
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}
	nested["added"] = "mutated-after-construction"

	_, err = engine.Run(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "nested-template-profile",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if err != nil {
		t.Fatalf("expected run to succeed, got %v", err)
	}
	want := map[string]any{
		"nested": map[string]any{
			"labels": map[string]string{"route": "primary"},
			"ids":    []int{1, 2, 3},
		},
	}
	if !reflect.DeepEqual(fake.requests[0].Target.ExtraParams, want) {
		t.Fatalf("unexpected extra params:\ngot=%#v\nwant=%#v", fake.requests[0].Target.ExtraParams, want)
	}
}

func TestInMemoryProfileAPIKeyRequiredBehavior(t *testing.T) {
	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir: frameworkPromptDir,
		SchemaDir: frameworkSchemaDir,
	}, promptkit.WithProfiles(promptkit.Profile{
		ID:             "requires-key",
		Endpoint:       "http://requires-key/v1",
		Model:          "requires-key-model",
		APIKeyRequired: true,
	}))
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	req := promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "requires-key",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	}
	_, err = engine.Prepare(context.Background(), req)
	if !errors.Is(err, promptkit.ErrInvalidRequest) {
		t.Fatalf("expected ErrInvalidRequest without API key, got %v", err)
	}
	req.APIKey = "direct-required-key"
	if _, err := engine.Prepare(context.Background(), req); err != nil {
		t.Fatalf("expected direct API key to satisfy APIKeyRequired, got %v", err)
	}
}

func TestInMemoryProfileWithoutAPIKeyRequiredWorksWithoutKey(t *testing.T) {
	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir: frameworkPromptDir,
		SchemaDir: frameworkSchemaDir,
	}, promptkit.WithProfiles(promptkit.Profile{
		ID:       "no-key-required",
		Endpoint: "http://no-key/v1",
		Model:    "no-key-model",
	}))
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	_, err = engine.Prepare(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "no-key-required",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if err != nil {
		t.Fatalf("expected prepare without API key to succeed, got %v", err)
	}
}

func TestInMemoryProfileExtraParamsAreCopiedAcrossPublicBoundary(t *testing.T) {
	fake := &fakeLLMClient{response: &promptkit.GenerateResponse{Content: "ok"}}
	labels := map[string]string{"route": "primary"}
	ids := []int{1, 2, 3}
	extraParams := map[string]any{
		"labels": labels,
		"ids":    ids,
	}

	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir: frameworkPromptDir,
		SchemaDir: frameworkSchemaDir,
	},
		promptkit.WithProfiles(promptkit.Profile{
			ID:          "copy-profile",
			Endpoint:    "http://copy/v1",
			Model:       "copy-model",
			ExtraParams: extraParams,
		}),
		promptkit.WithLLMClient(fake),
	)
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}
	labels["route"] = "mutated-before-run"
	ids[0] = 99
	extraParams["added"] = "mutated"

	_, err = engine.Run(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "copy-profile",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if err != nil {
		t.Fatalf("expected run to succeed, got %v", err)
	}
	want := map[string]any{
		"labels": map[string]string{"route": "primary"},
		"ids":    []int{1, 2, 3},
	}
	if !reflect.DeepEqual(fake.requests[0].Target.ExtraParams, want) {
		t.Fatalf("captured extra params changed after mutation:\ngot=%#v\nwant=%#v", fake.requests[0].Target.ExtraParams, want)
	}
}

func TestWithProfilesRejectsInvalidExtraParams(t *testing.T) {
	tests := []struct {
		name        string
		extraParams map[string]any
	}{
		{name: "function", extraParams: map[string]any{"bad": func() {}}},
		{name: "channel", extraParams: map[string]any{"bad": make(chan struct{})}},
		{name: "struct", extraParams: map[string]any{"bad": struct{ Name string }{Name: "bad"}}},
		{name: "non string map key", extraParams: map[string]any{"bad": map[int]string{1: "one"}}},
		{name: "nan", extraParams: map[string]any{"bad": math.NaN()}},
		{name: "positive infinity", extraParams: map[string]any{"bad": math.Inf(1)}},
		{name: "negative infinity", extraParams: map[string]any{"bad": math.Inf(-1)}},
		{name: "excessively large value", extraParams: map[string]any{"bad": excessivelyLargeJSONValue()}},
	}
	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			_, err := promptkit.NewEngine(promptkit.Config{PromptDir: frameworkPromptDir},
				promptkit.WithProfiles(promptkit.Profile{
					ID:          "invalid-extra-params",
					Endpoint:    "http://invalid/v1",
					Model:       "invalid-model",
					ExtraParams: tc.extraParams,
				}),
			)
			if !errors.Is(err, promptkit.ErrInvalidConfig) {
				t.Fatalf("expected ErrInvalidConfig, got %v", err)
			}
		})
	}
}

func TestWithProfilesRejectsCyclicExtraParams(t *testing.T) {
	cyclicMap := map[string]any{}
	cyclicMap["self"] = cyclicMap
	cyclicSlice := []any{nil}
	cyclicSlice[0] = cyclicSlice

	tests := []struct {
		name        string
		extraParams map[string]any
	}{
		{name: "map", extraParams: cyclicMap},
		{name: "slice", extraParams: map[string]any{"cycle": cyclicSlice}},
	}
	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			_, err := promptkit.NewEngine(promptkit.Config{PromptDir: frameworkPromptDir},
				promptkit.WithProfiles(promptkit.Profile{
					ID:          "cyclic-extra-params",
					Endpoint:    "http://cyclic/v1",
					Model:       "cyclic-model",
					ExtraParams: tc.extraParams,
				}),
			)
			if !errors.Is(err, promptkit.ErrInvalidConfig) {
				t.Fatalf("expected ErrInvalidConfig, got %v", err)
			}
		})
	}
}

func TestRunStructuredOutputWorksWithSchemaFS(t *testing.T) {
	fake := &fakeLLMClient{response: &promptkit.GenerateResponse{Content: `{"events":[]}`}}
	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  t.TempDir(),
		ProfileDir: frameworkProfileDir,
		SchemaDir:  t.TempDir(),
	},
		promptkit.WithPromptFS(publicStructuredPromptFS("schema.fs.prompt", "events.schema.json"), "prompts"),
		promptkit.WithSchemaFS(publicSchemaFS(), "schemas"),
		promptkit.WithLLMClient(fake),
	)
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	result, err := engine.Run(context.Background(), promptkit.RunRequest{
		PromptID: "schema.fs.prompt",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
		},
	})
	if err != nil {
		t.Fatalf("expected run to succeed, got %v", err)
	}
	if result.Validation.Status != promptkit.ValidationPassed || !result.Validation.IsValid {
		t.Fatalf("expected schema validation to pass, got %+v", result.Validation)
	}
	if len(fake.requests) != 1 || fake.requests[0].StructuredOutput == nil {
		t.Fatalf("expected structured output request, got %+v", fake.requests)
	}
}

func TestRunStructuredOutputWorksWithSchemaFile(t *testing.T) {
	schemaDir := t.TempDir()
	schemaPath := filepath.Join(schemaDir, "events.schema.json")
	if err := os.WriteFile(schemaPath, []byte(publicSchemaJSON()), 0o644); err != nil {
		t.Fatal(err)
	}

	fake := &fakeLLMClient{response: &promptkit.GenerateResponse{Content: `{"events":[]}`}}
	engine, err := promptkit.NewEngine(promptkit.Config{
		ProfileDir: frameworkProfileDir,
	},
		promptkit.WithPromptFS(publicStructuredPromptFS("schema.file.prompt", "events.schema.json"), "prompts"),
		promptkit.WithSchemaFile(schemaPath),
		promptkit.WithLLMClient(fake),
	)
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}

	result, err := engine.Run(context.Background(), promptkit.RunRequest{
		PromptID: "schema.file.prompt",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
		},
	})
	if err != nil {
		t.Fatalf("expected run to succeed, got %v", err)
	}
	if result.Validation.Status != promptkit.ValidationPassed || !result.Validation.IsValid {
		t.Fatalf("expected schema validation to pass, got %+v", result.Validation)
	}
}

func TestSourceOptionsRejectInvalidInputs(t *testing.T) {
	missingFile := filepath.Join(t.TempDir(), "missing.yaml")
	directoryPath := t.TempDir()

	tests := []struct {
		name string
		opt  promptkit.Option
	}{
		{name: "prompt fs nil", opt: promptkit.WithPromptFS(nil, "prompts")},
		{name: "prompt fs empty root", opt: promptkit.WithPromptFS(fstest.MapFS{}, "")},
		{name: "prompt file empty", opt: promptkit.WithPromptFile("")},
		{name: "prompt file missing", opt: promptkit.WithPromptFile(missingFile)},
		{name: "prompt file directory", opt: promptkit.WithPromptFile(directoryPath)},
		{name: "profile fs nil", opt: promptkit.WithProfileFS(nil, "profiles")},
		{name: "profile fs empty root", opt: promptkit.WithProfileFS(fstest.MapFS{}, "")},
		{name: "profile file empty", opt: promptkit.WithProfileFile("")},
		{name: "fallback profile fs nil", opt: promptkit.WithFallbackProfileFS(nil, "profiles")},
		{name: "fallback profile fs empty root", opt: promptkit.WithFallbackProfileFS(fstest.MapFS{}, "")},
		{name: "schema fs nil", opt: promptkit.WithSchemaFS(nil, "schemas")},
		{name: "schema fs empty root", opt: promptkit.WithSchemaFS(fstest.MapFS{}, "")},
		{name: "schema file empty", opt: promptkit.WithSchemaFile("")},
	}

	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			_, err := promptkit.NewEngine(promptkit.Config{PromptDir: frameworkPromptDir}, tc.opt)
			if !errors.Is(err, promptkit.ErrInvalidConfig) {
				t.Fatalf("expected ErrInvalidConfig, got %v", err)
			}
		})
	}
}

func TestPackageOptionsComposeFromSlice(t *testing.T) {
	fake := &fakeLLMClient{response: &promptkit.GenerateResponse{Content: "ok"}}
	options := []promptkit.Option{
		nil,
		promptkit.WithProfiles(promptkit.Profile{
			ID:       "slice-profile",
			Endpoint: "http://slice/v1",
			Model:    "slice-model",
		}),
		promptkit.WithLLMClient(fake),
	}

	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir: frameworkPromptDir,
		SchemaDir: frameworkSchemaDir,
	}, options...)
	if err != nil {
		t.Fatalf("expected package-provided options to compose, got %v", err)
	}

	_, err = engine.Run(context.Background(), promptkit.RunRequest{
		PromptID:  frameworkMarkdownSummaryPromptID,
		ProfileID: "slice-profile",
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
	})
	if err != nil {
		t.Fatalf("expected run with composed options to succeed, got %v", err)
	}
	if len(fake.requests) != 1 {
		t.Fatalf("expected one generate request, got %d", len(fake.requests))
	}
	if fake.requests[0].Target.Model != "slice-model" {
		t.Fatalf("expected profile from composed options, got %q", fake.requests[0].Target.Model)
	}
}

func TestExtraParamsTypedNestedValuesAreCopiedAcrossPublicBoundary(t *testing.T) {
	fake := &fakeLLMClient{response: &promptkit.GenerateResponse{Content: "ok"}}
	engine := newContractEngineWithOptions(t, frameworkSchemaDir, promptkit.WithLLMClient(fake))

	labels := map[string]string{"route": "primary"}
	counts := map[string]int{"retry_budget": 2}
	weights := []float64{0.25, 0.75}
	ids := []int{1, 2, 3}
	nested := map[string]any{
		"labels":  labels,
		"counts":  counts,
		"weights": weights,
		"ids":     ids,
	}
	extraParams := map[string]any{
		"labels": labels,
		"counts": counts,
		"nested": nested,
	}

	_, err := engine.Run(context.Background(), promptkit.RunRequest{
		PromptID: frameworkMarkdownSummaryPromptID,
		Inputs: map[string]promptkit.ArtifactRef{
			"transcript": promptkit.Inline("Rin opens the gate."),
			"glossary":   promptkit.Inline("gate: A guarded passage."),
		},
		Execution: &promptkit.ExecutionTargetOverride{ExtraParams: extraParams},
	})
	if err != nil {
		t.Fatalf("expected run to succeed, got %v", err)
	}
	if len(fake.requests) != 1 {
		t.Fatalf("expected one generate request, got %d", len(fake.requests))
	}

	captured := fake.requests[0].Target.ExtraParams
	labels["route"] = "mutated"
	counts["retry_budget"] = 99
	weights[0] = 9.9
	ids[0] = 99
	nested["added"] = "mutated"
	extraParams["new_top_level"] = "mutated"

	want := map[string]any{
		"labels": map[string]string{"route": "primary"},
		"counts": map[string]int{"retry_budget": 2},
		"nested": map[string]any{
			"labels":  map[string]string{"route": "primary"},
			"counts":  map[string]int{"retry_budget": 2},
			"weights": []float64{0.25, 0.75},
			"ids":     []int{1, 2, 3},
		},
	}
	if !reflect.DeepEqual(captured, want) {
		t.Fatalf("captured extra_params changed after mutating source:\ngot=%#v\nwant=%#v", captured, want)
	}
}

func TestRunRejectsInvalidExtraParams(t *testing.T) {
	cyclicMap := map[string]any{}
	cyclicMap["self"] = cyclicMap
	cyclicSlice := []any{nil}
	cyclicSlice[0] = cyclicSlice

	tests := []struct {
		name        string
		extraParams map[string]any
	}{
		{name: "function", extraParams: map[string]any{"bad": func() {}}},
		{name: "channel", extraParams: map[string]any{"bad": make(chan struct{})}},
		{name: "struct", extraParams: map[string]any{"bad": struct{ Name string }{Name: "bad"}}},
		{name: "non string map key", extraParams: map[string]any{"bad": map[int]string{1: "one"}}},
		{name: "nan", extraParams: map[string]any{"bad": math.NaN()}},
		{name: "positive infinity", extraParams: map[string]any{"bad": math.Inf(1)}},
		{name: "negative infinity", extraParams: map[string]any{"bad": math.Inf(-1)}},
		{name: "cyclic map", extraParams: cyclicMap},
		{name: "cyclic slice", extraParams: map[string]any{"cycle": cyclicSlice}},
		{name: "malformed JSON number", extraParams: map[string]any{"value": json.Number("+1")}},
		{name: "empty nested key", extraParams: map[string]any{"nested": map[string]any{"": true}}},
		{name: "excessively deep value", extraParams: map[string]any{"nested": excessivelyDeepJSONValue()}},
	}
	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			fake := &fakeLLMClient{response: &promptkit.GenerateResponse{Content: "ok"}}
			engine := newContractEngineWithOptions(t, frameworkSchemaDir, promptkit.WithLLMClient(fake))

			_, err := engine.Run(context.Background(), promptkit.RunRequest{
				PromptID: frameworkMarkdownSummaryPromptID,
				Inputs: map[string]promptkit.ArtifactRef{
					"transcript": promptkit.Inline("Rin opens the gate."),
					"glossary":   promptkit.Inline("gate: A guarded passage."),
				},
				Execution: &promptkit.ExecutionTargetOverride{ExtraParams: tc.extraParams},
			})
			if !errors.Is(err, promptkit.ErrInvalidRequest) {
				t.Fatalf("expected ErrInvalidRequest, got %v", err)
			}
			if len(fake.requests) != 0 {
				t.Fatalf("expected invalid request to fail before LLM call, got %d requests", len(fake.requests))
			}
		})
	}
}

func excessivelyDeepJSONValue() any {
	const clearlyUnsafeContainerDepth = 1_000
	var value any = true
	for level := 0; level < clearlyUnsafeContainerDepth; level++ {
		if level%2 == 0 {
			value = map[string]any{"child": value}
		} else {
			value = []any{value}
		}
	}
	return value
}

func excessivelyLargeJSONValue() any {
	const clearlyUnsafeSharedOccurrences = 60_000
	shared := []any{true}
	values := make([]any, clearlyUnsafeSharedOccurrences)
	for i := range values {
		values[i] = shared
	}
	return values
}

func TestWithLLMClientRejectsNilClient(t *testing.T) {
	_, err := promptkit.NewEngine(contractConfig(frameworkSchemaDir), promptkit.WithLLMClient(nil))
	if !errors.Is(err, promptkit.ErrInvalidConfig) {
		t.Fatalf("expected ErrInvalidConfig, got %v", err)
	}
}

func TestNewEngineConstructsDefaultLLMClientWithoutCredentials(t *testing.T) {
	if _, err := promptkit.NewEngine(contractConfig(frameworkSchemaDir)); err != nil {
		t.Fatalf("expected default engine construction without credentials to succeed, got %v", err)
	}
}

func newContractEngine(t *testing.T) *promptkit.Engine {
	t.Helper()

	for _, path := range []string{
		frameworkPromptDir,
		frameworkProfileDir,
		frameworkSchemaDir,
	} {
		if _, err := os.Stat(path); err != nil {
			t.Fatalf("expected framework contract path %s to exist: %v", path, err)
		}
	}

	engine, err := promptkit.NewEngine(contractConfig(frameworkSchemaDir))
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}
	return engine
}

func newContractEngineWithOptions(t *testing.T, schemaDir string, opts ...promptkit.Option) *promptkit.Engine {
	t.Helper()

	engine, err := promptkit.NewEngine(contractConfig(schemaDir), opts...)
	if err != nil {
		t.Fatalf("expected engine construction to succeed, got %v", err)
	}
	return engine
}

func newArtifactReaderEngine(t *testing.T, reader promptkit.ArtifactReader) *promptkit.Engine {
	t.Helper()

	promptDir := t.TempDir()
	writePublicPromptFile(t, promptDir, "artifact-reader", frameworkFastProfileID)
	engine, err := promptkit.NewEngine(promptkit.Config{
		PromptDir:  promptDir,
		ProfileDir: frameworkProfileDir,
		SchemaDir:  frameworkSchemaDir,
	}, promptkit.WithArtifactReader(reader))
	if err != nil {
		t.Fatalf("construct engine with artifact reader: %v", err)
	}
	return engine
}

func contractConfig(schemaDir string) promptkit.Config {
	return promptkit.Config{
		PromptDir:  frameworkPromptDir,
		ProfileDir: frameworkProfileDir,
		SchemaDir:  schemaDir,
	}
}

func writePublicPromptFile(t *testing.T, dir, id, defaultProfile string) {
	t.Helper()
	data := `id: ` + id + `
version: "1.0.0"
default_profile: ` + defaultProfile + `
inputs:
  - name: transcript
    required: true
messages:
  - role: user
    content: "Summarize: {{input \"transcript\"}}"
output:
  format: text
  validation_mode: none
  repair_attempts: 0
`
	if err := os.WriteFile(filepath.Join(dir, id+".yaml"), []byte(data), 0o644); err != nil {
		t.Fatalf("failed to write prompt fixture: %v", err)
	}
}

func writePublicProfileFile(t *testing.T, dir, id, endpoint, model string) {
	t.Helper()
	data := `id: ` + id + `
endpoint: ` + endpoint + `
model: ` + model + `
`
	if err := os.WriteFile(filepath.Join(dir, id+".yaml"), []byte(data), 0o644); err != nil {
		t.Fatalf("failed to write profile fixture: %v", err)
	}
}

func writePublicProfileFileWithAPIKeyEnv(t *testing.T, dir, id, endpoint, model, apiKeyEnv string) {
	t.Helper()
	data := `id: ` + id + `
endpoint: ` + endpoint + `
model: ` + model + `
api_key_env: ` + apiKeyEnv + `
`
	if err := os.WriteFile(filepath.Join(dir, id+".yaml"), []byte(data), 0o644); err != nil {
		t.Fatalf("failed to write profile fixture: %v", err)
	}
}

func publicStructuredPromptFS(id string, schemaPath string) fstest.MapFS {
	return fstest.MapFS{
		"prompts/prompt.yaml": &fstest.MapFile{Data: []byte(`id: ` + id + `
version: "1.0.0"
default_profile: contract-fast
inputs:
  - name: transcript
    required: true
messages:
  - role: user
    content: "Extract events from {{input \"transcript\"}}."
output:
  format: json
  validation_mode: json_schema
  schema_path: ` + schemaPath + `
  repair_attempts: 0
`)},
	}
}

func publicSchemaFS() fstest.MapFS {
	return fstest.MapFS{
		"schemas/events.schema.json": &fstest.MapFile{Data: []byte(publicSchemaJSON())},
	}
}

func publicSchemaJSON() string {
	return `{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "type": "object",
  "required": ["events"],
  "properties": {
    "events": {"type": "array"}
  }
}`
}

type executionProfileFixture struct {
	id               string
	endpoint         string
	model            string
	temperature      float64
	maxTokens        int
	topP             float64
	timeoutSeconds   int
	serviceTier      string
	reasoningEffort  string
	apiKeyEnv        string
	extraParamSource string
}

func executionTargetFromProfileFixture(profile executionProfileFixture) promptkit.ExecutionTarget {
	return promptkit.ExecutionTarget{
		Endpoint:        profile.endpoint,
		Model:           profile.model,
		Temperature:     profile.temperature,
		MaxTokens:       profile.maxTokens,
		TopP:            profile.topP,
		TimeoutSeconds:  profile.timeoutSeconds,
		ServiceTier:     profile.serviceTier,
		ReasoningEffort: profile.reasoningEffort,
		APIKeyEnv:       profile.apiKeyEnv,
		ExtraParams:     map[string]any{"source": profile.extraParamSource},
	}
}

func writeExecutionProfileFixture(t *testing.T, dir string, profile executionProfileFixture) {
	t.Helper()
	data := fmt.Sprintf(`id: %s
endpoint: %s
model: %s
temperature: %g
max_tokens: %d
top_p: %g
timeout_seconds: %d
service_tier: %s
reasoning_effort: %s
api_key_env: %s
extra_params:
  source: %q
`,
		profile.id,
		profile.endpoint,
		profile.model,
		profile.temperature,
		profile.maxTokens,
		profile.topP,
		profile.timeoutSeconds,
		profile.serviceTier,
		profile.reasoningEffort,
		profile.apiKeyEnv,
		profile.extraParamSource,
	)
	if err := os.WriteFile(filepath.Join(dir, profile.id+".yaml"), []byte(data), 0o644); err != nil {
		t.Fatalf("write execution profile fixture: %v", err)
	}
}

type fakeLLMClient struct {
	response *promptkit.GenerateResponse
	err      error
	requests []promptkit.GenerateRequest
}

type recordingArtifactReader struct {
	artifact *promptkit.Artifact
	err      error
	refs     []promptkit.ArtifactRef
	read     func(context.Context, promptkit.ArtifactRef) (*promptkit.Artifact, error)
}

func (r *recordingArtifactReader) Read(ctx context.Context, ref promptkit.ArtifactRef) (*promptkit.Artifact, error) {
	r.refs = append(r.refs, ref)
	if r.read != nil {
		return r.read(ctx, ref)
	}
	if r.err != nil {
		return nil, r.err
	}
	return r.artifact, nil
}

type roundTripFunc func(*http.Request) (*http.Response, error)

func (f roundTripFunc) RoundTrip(req *http.Request) (*http.Response, error) {
	return f(req)
}

func (f *fakeLLMClient) Generate(_ context.Context, req promptkit.GenerateRequest) (*promptkit.GenerateResponse, error) {
	f.requests = append(f.requests, req)
	if f.err != nil {
		return nil, f.err
	}
	return f.response, nil
}