package grammar

import (
	"context"
	"errors"
	"os"
	"path/filepath"
	"strings"
	"testing"

	ck "gitea.maximumdirect.net/eric/ConfigKit"
	"gitea.maximumdirect.net/eric/audita/internal/core/config"
	"gitea.maximumdirect.net/eric/audita/internal/core/schema"
	"gitea.maximumdirect.net/eric/audita/internal/framework/contracts"
	"gitea.maximumdirect.net/eric/audita/internal/framework/proposal_generation"
	"gitea.maximumdirect.net/eric/audita/internal/framework/proposals"
	"gitea.maximumdirect.net/eric/audita/internal/prompts"
)

type fakeLLMClient struct {
	responses []map[string]any
	err       error
	calls     []contracts.StructuredCompletionRequest
}

func (f *fakeLLMClient) CompleteStructured(ctx context.Context, req contracts.StructuredCompletionRequest, out any) (contracts.StructuredCompletionResponse, error) {
	_ = ctx
	f.calls = append(f.calls, req)
	if f.err != nil {
		return contracts.StructuredCompletionResponse{}, f.err
	}
	if len(f.responses) == 0 {
		return contracts.StructuredCompletionResponse{}, errors.New("unexpected call")
	}
	payload := f.responses[0]
	f.responses = f.responses[1:]

	target, ok := out.(*proposal_generation.StructuredCorrectionSet)
	if !ok {
		return contracts.StructuredCompletionResponse{}, errors.New("unexpected output type")
	}
	items, _ := payload["corrections"].([]map[string]any)
	for _, item := range items {
		target.Corrections = append(target.Corrections, proposal_generation.StructuredCorrectionProposal{
			TargetSegmentID: item["id"].(int),
			OriginalText:    item["original_text"].(string),
			CorrectedText:   item["corrected_text"].(string),
			Confidence:      item["confidence"].(float64),
		})
	}
	return contracts.StructuredCompletionResponse{}, nil
}

func tinyTranscript() *schema.Transcript {
	return &schema.Transcript{Segments: []schema.Segment{
		{ID: 1, Speaker: "A", Start: 0, End: 1, Text: "hello ,world"},
	}}
}

func tinyGlossary() *schema.Glossary {
	return &schema.Glossary{Entries: []schema.GlossaryEntry{
		{Name: "Jesters", Category: "faction", Summary: "Faction", Aliases: []string{"Jester"}},
	}}
}

func TestGrammarModuleReplacementPolicy(t *testing.T) {
	m, err := New()
	if err != nil {
		t.Fatalf("New error: %v", err)
	}
	if m.ReplacementPolicy() != proposals.ReplacementPolicyRequireUnique {
		t.Fatalf("unexpected replacement policy: %q", m.ReplacementPolicy())
	}
}

func TestGrammarModuleValidatorChain(t *testing.T) {
	m, err := New()
	if err != nil {
		t.Fatalf("New error: %v", err)
	}
	got := make([]string, 0, len(m.Validators()))
	for _, v := range m.Validators() {
		got = append(got, v.Name())
	}
	want := []string{
		"proposal_shape",
		"no_effect",
		"original_text_presence",
		"confidence_threshold",
		"protected_terms",
		"non_empty_resulting_segment",
		"editorial_review",
		"meaning_reversal_review",
	}
	if strings.Join(got, ",") != strings.Join(want, ",") {
		t.Fatalf("unexpected validator chain\n got: %v\nwant: %v", got, want)
	}
}

func TestGrammarModuleProposeMapsCorrectionsAndWritesDiagnostics(t *testing.T) {
	secret := "super-secret-key"
	client := &fakeLLMClient{
		responses: []map[string]any{
			{
				"corrections": []map[string]any{
					{"id": 1, "original_text": "hello ,world", "corrected_text": "Hello, world", "confidence": 0.93},
				},
			},
		},
	}
	t.Setenv("MODULE_SECRET", secret)
	loaded, loadErr := config.Load(ck.Bytes("config.yml", []byte("version: 2\nbackends:\n  offline:\n    endpoint: https://offline.invalid/v1\n    credential: MODULE_SECRET\nllm:\n  proposal_profile: base\n")), "")
	if loadErr != nil {
		t.Fatal(loadErr)
	}
	cfg := loaded.Config
	module, err := New()
	if err != nil {
		t.Fatalf("New error: %v", err)
	}
	diagDir := t.TempDir()
	out, err := module.Propose(context.Background(), contracts.ProposalRequest{
		ExecutionContext: contracts.ExecutionContext{
			Config:            &cfg,
			WorkingTranscript: tinyTranscript(),
			Glossary:          tinyGlossary(),
			DiagnosticsDir:    diagDir,
		},
		RunSpec: contracts.ModuleRunSpec{
			ModuleKey:         "grammar",
			InstanceName:      "grammar",
			ReplacementPolicy: proposals.ReplacementPolicyRequireUnique,
		},
		LLMClient: client,
	})
	if err != nil {
		t.Fatalf("Propose error: %v", err)
	}

	if len(client.calls) != 1 || client.calls[0].PromptID != prompts.PromptIDModuleGrammarProposal {
		t.Fatalf("expected one grammar:proposal call, got %+v", client.calls)
	}
	call := client.calls[0]
	if call.Schema != "correction_set" || call.Context.Role != "proposal" || !strings.Contains(call.Variables["SectionJSON"], "section_index") || !strings.Contains(call.Variables["GlossaryJSON"], "Jesters") {
		t.Fatalf("proposal mapping incomplete: %+v", call)
	}

	if len(out.Proposals) != 1 || out.Proposals[0].CorrectedText != "Hello, world" {
		t.Fatalf("unexpected proposals: %+v", out)
	}
	diagFiles, globErr := filepath.Glob(filepath.Join(diagDir, "grammar", "*proposal*response-payload.json"))
	if globErr != nil {
		t.Fatalf("glob error: %v", globErr)
	}
	if len(diagFiles) == 0 {
		t.Fatalf("expected diagnostics response payload under %s", filepath.Join(diagDir, "grammar"))
	}
	for _, f := range diagFiles {
		raw, readErr := os.ReadFile(f)
		if readErr != nil {
			t.Fatalf("read diag %q: %v", f, readErr)
		}
		if strings.Contains(string(raw), secret) {
			t.Fatalf("secret leaked in diagnostics: %s", string(raw))
		}
	}
}