package integration_test

import (
	"context"
	"encoding/json"
	"fmt"
	"os"
	"reflect"
	"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"
	npccodec "gitea.maximumdirect.net/eric/notarius/internal/modules/dnd/codec/npcs"
	"gitea.maximumdirect.net/eric/notarius/internal/modules/dnd/extract/npcs"
	"gitea.maximumdirect.net/eric/notarius/internal/modules/dnd/npcs/identity"
	dndregister "gitea.maximumdirect.net/eric/notarius/internal/modules/dnd/register"
	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-npcs-fixture", Catalog: moduleCatalog(registries)})
	if err != nil {
		t.Fatalf("Resolve() error = %v, want nil", err)
	}

	client := &fakeNPCProductionLLMClient{response: npcProductionResponse{
		NPCs: []npcProductionRecord{
			{
				Name:        "Mira Thorn",
				Aliases:     []string{"The Greencloak"},
				Description: "The first named NPC encountered.",
				Relationships: []npcProductionRelationship{
					{Target: "Hooded Guard", Relationship: "works with"},
				},
				SourceRefs: []npcProductionSourceRef{{StartUnitID: 1, EndUnitID: 1}},
			},
			{
				Name:        "The Greencloak",
				Aliases:     []string{"Mira"},
				Description: "A later description that must not replace the first.",
				Relationships: []npcProductionRelationship{
					{Target: "Hooded Guard", Relationship: "trusts"},
				},
				SourceRefs: []npcProductionSourceRef{{StartUnitID: 2, EndUnitID: 2}},
			},
			{
				Name:        "Hooded Guard",
				Aliases:     []string{},
				Description: "An unnamed but distinguishable sentry.",
				Relationships: []npcProductionRelationship{
					{Target: "The Greencloak", Relationship: "reports to"},
				},
				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 != "npcs" || serialized.NormalizerKey != npcs.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" || first.Description != "The first named NPC encountered." || !reflect.DeepEqual(first.Aliases, []string{"The Greencloak", "Mira"}) {
		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)
	}
	if first.Relationships[0].Target != "Hooded Guard" || second.Relationships[0].Target != "Mira Thorn" {
		t.Fatalf("relationship targets = %q/%q, want canonical target rewrite", first.Relationships[0].Target, second.Relationships[0].Target)
	}
	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") || !hasNPCWarning(output.Warnings, "relationship_target_canonicalized") {
		t.Fatalf("warnings = %#v, want consolidation and target warnings", 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 != "npcs" || lane.Extractor != npcs.Key || lane.Merger != pipeline.DefaultMergeModule || lane.Normalizer != npcs.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"] != "dnd.npcs.normalize.v1" {
		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/npcs.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) != 1 || client.requests[0].PromptID != npcs.PromptID {
		t.Fatalf("LLM requests = %#v, want one NPC prompt request", client.requests)
	}
}

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

type npcProductionRecord struct {
	Name          string                      `json:"name"`
	Aliases       []string                    `json:"aliases"`
	Description   string                      `json:"description"`
	Relationships []npcProductionRelationship `json:"relationships"`
	SourceRefs    []npcProductionSourceRef    `json:"source_refs"`
}

type npcProductionRelationship struct {
	Target       string `json:"target"`
	Relationship string `json:"relationship"`
}

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

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

func (client *fakeNPCProductionLLMClient) CompleteStructured(_ context.Context, req contracts.StructuredCompletionRequest, out any) (contracts.StructuredCompletionResponse, error) {
	client.requests = append(client.requests, req)
	content, err := json.Marshal(client.response)
	if err != nil {
		return contracts.StructuredCompletionResponse{}, err
	}
	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 productionNPCRegistries(t *testing.T) pipeline.Registries {
	t.Helper()
	registries := pipeline.Registries{
		Inputs:          pipeline.NewInputAdapterRegistry(),
		Chunkers:        pipeline.NewChunkerRegistry(),
		ArtifactCodecs:  pipeline.NewArtifactCodecRegistry(),
		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,
		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_npcs_pipeline.yml")
	if err != nil {
		t.Fatalf("ReadFile(dnd_npcs_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
}