package integration_test

import (
	"context"
	"encoding/json"
	"fmt"
	"os"
	"strings"
	"testing"

	"gitea.maximumdirect.net/eric/notarius/internal/core/config"
	"gitea.maximumdirect.net/eric/notarius/internal/framework/contracts"
	"gitea.maximumdirect.net/eric/notarius/internal/framework/llm"
	"gitea.maximumdirect.net/eric/notarius/internal/framework/pipeline"
	"gitea.maximumdirect.net/eric/notarius/internal/framework/semanticreconcile"
	npccodec "gitea.maximumdirect.net/eric/notarius/internal/modules/dnd/codec/npcregistry"
	"gitea.maximumdirect.net/eric/notarius/internal/modules/dnd/extract/npcregistry"
	npcnormalize "gitea.maximumdirect.net/eric/notarius/internal/modules/dnd/normalize/npcregistry"
	"gitea.maximumdirect.net/eric/notarius/internal/modules/dnd/npcs/identity"
	dndregister "gitea.maximumdirect.net/eric/notarius/internal/modules/dnd/register"
	npcshape "gitea.maximumdirect.net/eric/notarius/internal/modules/dnd/validate/npcregistry/shape"
	npcregistrysourcerefs "gitea.maximumdirect.net/eric/notarius/internal/modules/dnd/validate/npcregistry/source_refs"
	genericregister "gitea.maximumdirect.net/eric/notarius/internal/modules/generic/register"
	"gitea.maximumdirect.net/eric/notarius/internal/modules/seriatim/input/transcript"
	seriatimregister "gitea.maximumdirect.net/eric/notarius/internal/modules/seriatim/register"
)

func TestRunnerProcessesSeriatimInputWithProductionDNDNPCPipeline(t *testing.T) {
	raw := readNPCFixture(t)
	doc, err := transcript.New().Parse(context.Background(), contracts.ParseRequest{Raw: raw})
	if err != nil {
		t.Fatalf("Parse() error = %v, want nil", err)
	}
	registries := productionNPCRegistries(t)
	configValue := loadNPCPipelineConfig(t)
	effective, err := configValue.Resolve(config.ResolveInput{PipelineID: "dnd-npc-registry-fixture", Catalog: moduleCatalog(registries)})
	if err != nil {
		t.Fatalf("Resolve() error = %v, want nil", err)
	}

	client := &fakeNPCProductionLLMClient{response: npcProductionResponse{
		NPCs: []npcProductionRecord{
			{
				Name:       "Mira Thorn",
				SourceRefs: []npcProductionSourceRef{{StartUnitID: 1, EndUnitID: 1}},
			},
			{
				Name:       " mira thorn ",
				SourceRefs: []npcProductionSourceRef{{StartUnitID: 2, EndUnitID: 2}},
			},
			{
				Name:       "Hooded Guard",
				SourceRefs: []npcProductionSourceRef{{StartUnitID: 3, EndUnitID: 3}},
			},
		}},
	}
	output, err := runPreparedPipeline(t, registries, effective.ResolvedPipeline, client, pipeline.RunInput{RawInput: raw})
	if err != nil {
		t.Fatalf("Run() error = %v, want nil", err)
	}
	if len(output.NormalizeOutputs) != 1 {
		t.Fatalf("normalize outputs = %d, want one NPC output; rejected=%#v", len(output.NormalizeOutputs), output.Rejected)
	}
	serialized := output.NormalizeOutputs[0]
	if serialized.LaneID != "npc_registry" || serialized.NormalizerKey != npcregistry.Key || serialized.Artifact.Schema.ID != npccodec.SchemaID || serialized.Artifact.Schema.Version != npccodec.SchemaVersion {
		t.Fatalf("serialized output = %#v, want durable NPC lane schema", serialized)
	}
	value, err := npccodec.New().Decode(serialized.Artifact.Content)
	if err != nil {
		t.Fatalf("Decode(output) error = %v, want durable NPC payload", err)
	}
	if len(value.NPCs) != 2 {
		t.Fatalf("NPC output = %#v, want repeated name consolidated and group/PC omitted", value.NPCs)
	}
	first, second := value.NPCs[0], value.NPCs[1]
	if first.Name != "Mira Thorn" || len(first.SourceRefs) != 2 {
		t.Fatalf("first NPC = %#v, want consolidated Mira identity", first)
	}
	if first.ID != identity.DeriveID(first.Name) || second.Name != "Hooded Guard" || second.ID != identity.DeriveID(second.Name) {
		t.Fatalf("NPC IDs = %q/%q, want derived IDs", first.ID, second.ID)
	}
	for _, npc := range value.NPCs {
		for _, ref := range npc.SourceRefs {
			if ref.SourceID != doc.ID {
				t.Fatalf("NPC source ref = %#v, want source document %q", ref, doc.ID)
			}
		}
	}
	if !hasNPCWarning(output.Warnings, "duplicate_npc_collapsed") {
		t.Fatalf("warnings = %#v, want name-only consolidation warning", output.Warnings)
	}
	if output.Manifest.ValidationStatus != "approved" || len(output.Manifest.ArtifactLanes) != 1 {
		t.Fatalf("manifest = %#v, want approved NPC lane", output.Manifest)
	}
	lane := output.Manifest.ArtifactLanes[0]
	if lane.ID != "npc_registry" || lane.Extractor != npcregistry.Key || lane.Merger != pipeline.DefaultMergeModule || lane.Normalizer != npcregistry.Key {
		t.Fatalf("manifest lane = %#v, want NPC production composition", lane)
	}
	normalizerMetadata, ok := lane.Metadata["normalizer"].(map[string]any)
	if !ok || normalizerMetadata["identity_policy"] != identity.Policy || normalizerMetadata["normalization_policy"] != npcnormalize.NormalizationPolicy || normalizerMetadata["prompt_id"] != npcnormalize.PromptID || normalizerMetadata["response_schema_id"] != semanticreconcile.ResponseSchemaID {
		t.Fatalf("normalizer metadata = %#v, want identity and normalization policies", lane.Metadata)
	}
	var npcOutputFile *contracts.OutputFile
	for index := range output.OutputFiles {
		if output.OutputFiles[index].Name == "lanes/npc_registry.json" {
			npcOutputFile = &output.OutputFiles[index]
			break
		}
	}
	if npcOutputFile == nil || npcOutputFile.ContentType != npccodec.MediaType {
		t.Fatalf("output files = %#v, want JSON NPC lane file", output.OutputFiles)
	}
	if len(client.requests) != 2 || client.requests[0].PromptID != npcregistry.PromptID || client.requests[1].PromptID != npcnormalize.PromptID {
		t.Fatalf("LLM requests = %#v, want extraction and normalization prompt requests", client.requests)
	}
}

func TestProductionNPCPipelineRoutesSemanticCandidatesToDeterministicValidators(t *testing.T) {
	registries := productionNPCRegistries(t)
	effective, err := loadNPCPipelineConfig(t).Resolve(config.ResolveInput{
		PipelineID: "dnd-npc-registry-fixture",
		Catalog:    moduleCatalog(registries),
	})
	if err != nil {
		t.Fatalf("Resolve() error = %v, want nil", err)
	}
	for _, test := range []struct {
		name          string
		response      []byte
		reasonCode    string
		validatorName string
	}{
		{
			name:          "blank string",
			response:      []byte(`{"npcs":[{"name":"","source_refs":[{"start_unit_id":1,"end_unit_id":1}]}]}`),
			reasonCode:    npcshape.ReasonCode,
			validatorName: npcshape.Key,
		},
		{
			name:          "empty evidence",
			response:      []byte(`{"npcs":[{"name":"Mira Thorn","source_refs":[]}]}`),
			reasonCode:    npcshape.ReasonCode,
			validatorName: npcshape.Key,
		},
		{
			name:          "nonpositive unit candidate",
			response:      []byte(`{"npcs":[{"name":"Mira Thorn","source_refs":[{"start_unit_id":0,"end_unit_id":1}]}]}`),
			reasonCode:    npcregistrysourcerefs.ReasonCode,
			validatorName: npcregistrysourcerefs.Key,
		},
		{
			name:          "unknown unit candidate",
			response:      []byte(`{"npcs":[{"name":"Mira Thorn","source_refs":[{"start_unit_id":99,"end_unit_id":99}]}]}`),
			reasonCode:    npcregistrysourcerefs.ReasonCode,
			validatorName: npcregistrysourcerefs.Key,
		},
	} {
		t.Run(test.name, func(t *testing.T) {
			client := &fakeNPCProductionLLMClient{rawResponses: [][]byte{test.response, test.response, test.response}}
			output, err := runPreparedPipeline(t, registries, effective.ResolvedPipeline, client, pipeline.RunInput{RawInput: readNPCFixture(t)})
			if err != nil {
				t.Fatalf("Run() error = %v, want non-fatal rejected output", err)
			}
			if len(client.requests) != 3 || len(output.Rejected) != 1 || len(output.NormalizeOutputs) != 0 {
				t.Fatalf("LLM requests = %d rejected = %#v normalized = %#v, want exhausted rejection", len(client.requests), output.Rejected, output.NormalizeOutputs)
			}
			rejection := output.Rejected[0]
			if rejection.ReasonCode != test.reasonCode || rejection.ValidatorName != test.validatorName || rejection.AttemptCount != 3 {
				t.Fatalf("rejection = %#v, want exhausted %s rejection", rejection, test.validatorName)
			}
		})
	}
}

func TestProductionNPCNormalizationRetryUsesFinalSafeProposal(t *testing.T) {
	registries := productionNPCRegistries(t)
	baseResponse := npcProductionResponse{NPCs: []npcProductionRecord{
		{Name: "Mira", SourceRefs: []npcProductionSourceRef{{StartUnitID: 1, EndUnitID: 1}}},
		{Name: "Mira Thorn", SourceRefs: []npcProductionSourceRef{{StartUnitID: 2, EndUnitID: 2}}},
		{Name: "Hooded Guard", SourceRefs: []npcProductionSourceRef{{StartUnitID: 3, EndUnitID: 3}}},
	}}
	partial := []byte(`{"duplicate_groups":[{"candidate_ids":[1,2],"canonical_candidate_id":2},{"candidate_ids":[3,99],"canonical_candidate_id":3}]}`)
	safe := []byte(`{"duplicate_groups":[{"candidate_ids":[1,2],"canonical_candidate_id":2}]}`)

	for _, test := range []struct {
		name           string
		retries        int
		responses      [][]byte
		wantCalls      int
		wantExhaustion bool
	}{
		{name: "default retry budget", responses: [][]byte{partial}, wantCalls: 1, wantExhaustion: true},
		{name: "later complete proposal", retries: 1, responses: [][]byte{partial, safe}, wantCalls: 2},
	} {
		t.Run(test.name, func(t *testing.T) {
			cfg := loadNPCPipelineConfig(t)
			profile := cfg.Pipelines["dnd-npc-registry-fixture"]
			lane := profile.Artifacts["npc_registry"]
			lane.Normalize.Retries = test.retries
			profile.Artifacts["npc_registry"] = lane
			cfg.Pipelines["dnd-npc-registry-fixture"] = profile
			effective, err := cfg.Resolve(config.ResolveInput{PipelineID: "dnd-npc-registry-fixture", Catalog: moduleCatalog(registries)})
			if err != nil {
				t.Fatal(err)
			}
			client := &fakeNPCProductionLLMClient{response: baseResponse, normalizeResponses: test.responses}
			output, err := runPreparedPipeline(t, registries, effective.ResolvedPipeline, client, pipeline.RunInput{RawInput: readNPCFixture(t)})
			if err != nil {
				t.Fatalf("Run() error = %v", err)
			}
			if client.requestCount(npcnormalize.PromptID) != test.wantCalls || len(output.NormalizeOutputs) != 1 {
				t.Fatalf("normalization calls = %d output = %#v, want %d accepted result", client.requestCount(npcnormalize.PromptID), output.NormalizeOutputs, test.wantCalls)
			}
			if got := hasWarningReason(output.Warnings, npcnormalize.ReasonCodeNPCSemanticReconciliationExhausted); got != test.wantExhaustion {
				t.Fatalf("warnings = %#v, exhaustion = %t, want %t", output.Warnings, got, test.wantExhaustion)
			}
		})
	}
}

type npcProductionResponse struct {
	NPCs []npcProductionRecord `json:"npcs"`
}

type npcProductionRecord struct {
	Name       string                   `json:"name"`
	SourceRefs []npcProductionSourceRef `json:"source_refs"`
}

type npcProductionSourceRef struct {
	StartUnitID int `json:"start_unit_id"`
	EndUnitID   int `json:"end_unit_id"`
}

type fakeNPCProductionLLMClient struct {
	response           npcProductionResponse
	rawResponses       [][]byte
	normalizeResponses [][]byte
	requests           []contracts.StructuredCompletionRequest
}

func (client *fakeNPCProductionLLMClient) CompleteStructured(_ context.Context, req contracts.StructuredCompletionRequest, out any) (contracts.StructuredCompletionResponse, error) {
	client.requests = append(client.requests, req)
	var content []byte
	switch req.PromptID {
	case npcregistry.PromptID:
		if client.rawResponses != nil {
			index := client.requestCount(npcregistry.PromptID) - 1
			if index >= len(client.rawResponses) {
				return contracts.StructuredCompletionResponse{}, fmt.Errorf("missing fake NPC response %d", index)
			}
			content = append([]byte(nil), client.rawResponses[index]...)
		} else {
			var err error
			content, err = json.Marshal(client.response)
			if err != nil {
				return contracts.StructuredCompletionResponse{}, err
			}
		}
	case npcnormalize.PromptID:
		content = []byte(`{"duplicate_groups":[]}`)
		if client.normalizeResponses != nil {
			index := client.requestCount(npcnormalize.PromptID) - 1
			if index >= len(client.normalizeResponses) {
				return contracts.StructuredCompletionResponse{}, fmt.Errorf("missing fake NPC normalization response %d", index)
			}
			content = append([]byte(nil), client.normalizeResponses[index]...)
		}
	default:
		return contracts.StructuredCompletionResponse{}, fmt.Errorf("unexpected fake NPC prompt %q", req.PromptID)
	}
	if err := json.Unmarshal(content, out); err != nil {
		return contracts.StructuredCompletionResponse{}, fmt.Errorf("populate NPC structured target: %w", err)
	}
	return contracts.StructuredCompletionResponse{Content: content}, nil
}

func (client *fakeNPCProductionLLMClient) requestCount(promptID string) int {
	count := 0
	for _, request := range client.requests {
		if request.PromptID == promptID {
			count++
		}
	}
	return count
}

func productionNPCRegistries(t *testing.T) pipeline.Registries {
	t.Helper()
	registries := pipeline.Registries{
		Inputs:           pipeline.NewInputAdapterRegistry(),
		Chunkers:         pipeline.NewChunkerRegistry(),
		ArtifactCodecs:   pipeline.NewArtifactCodecRegistry(),
		ArtifactEvidence: pipeline.NewArtifactEvidenceRegistry(),
		Extractors:       pipeline.NewExtractorRegistry(),
		Mergers:          pipeline.NewMergerRegistry(),
		Normalizers:      pipeline.NewNormalizerRegistry(),
		Validators:       pipeline.NewValidatorRegistry(),
		ValidatorChains:  pipeline.NewValidatorChainRegistry(),
		Outputs:          pipeline.NewOutputEncoderRegistry(),
	}
	assets := llm.NewAssetRegistry()
	for _, registration := range []struct {
		name string
		fn   func(pipeline.Registries, *llm.AssetRegistry) error
	}{
		{name: "generic", fn: genericregister.Register},
		{name: "seriatim", fn: seriatimregister.Register},
		{name: "dnd", fn: dndregister.Register},
	} {
		if err := registration.fn(registries, assets); err != nil {
			t.Fatalf("register %s modules: %v", registration.name, err)
		}
	}
	return registries
}

func moduleCatalog(registries pipeline.Registries) pipeline.ModuleCatalog {
	return pipeline.ModuleCatalog{
		Inputs: registries.Inputs, Chunkers: registries.Chunkers, ArtifactCodecs: registries.ArtifactCodecs, ArtifactEvidence: registries.ArtifactEvidence,
		Extractors: registries.Extractors, Mergers: registries.Mergers, Normalizers: registries.Normalizers,
		Validators: registries.Validators, ValidatorChains: registries.ValidatorChains, Outputs: registries.Outputs,
	}
}

func loadNPCPipelineConfig(t *testing.T) config.Config {
	t.Helper()
	data, err := os.ReadFile("testdata/dnd_npc_registry_pipeline.yml")
	if err != nil {
		t.Fatalf("ReadFile(dnd_npc_registry_pipeline.yml) error = %v", err)
	}
	fileConfig, err := config.ParseFileConfigYAML(data)
	if err != nil {
		t.Fatalf("ParseFileConfigYAML() error = %v", err)
	}
	cfg := config.Default()
	if err := cfg.ApplyFileConfig(fileConfig); err != nil {
		t.Fatalf("ApplyFileConfig() error = %v", err)
	}
	return cfg
}

func readNPCFixture(t *testing.T) []byte {
	t.Helper()
	raw, err := os.ReadFile("testdata/seriatim_npc_session.json")
	if err != nil {
		t.Fatalf("ReadFile(seriatim_npc_session.json) error = %v", err)
	}
	return raw
}

func hasNPCWarning(warnings []contracts.Warning, reason string) bool {
	for _, warning := range warnings {
		if warning.ReasonCode == reason && strings.HasPrefix(warning.Scope, "npcs[") {
			return true
		}
	}
	return false
}

func hasWarningReason(warnings []contracts.Warning, reason string) bool {
	for _, warning := range warnings {
		if warning.ReasonCode == reason {
			return true
		}
	}
	return false
}