package artifacts

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

	"gitea.maximumdirect.net/eric/narratio/internal/manifest"
)

func TestNormalizeSessionArtifactSource(t *testing.T) {
	tests := []struct {
		name    string
		source  string
		wantID  string
		wantErr string
	}{
		{name: "legacy alias processed unsupported", source: "processed_transcript", wantErr: "unsupported artifact source"},
		{name: "legacy alias normalized unsupported", source: "normalized_transcript", wantErr: "unsupported artifact source"},
		{name: "legacy alias trimmed unsupported", source: "trimmed_transcript", wantErr: "unsupported artifact source"},
		{name: "canonical", source: ArtifactTranscriptTrimmed, wantID: ArtifactTranscriptTrimmed},
		{name: "unsupported", source: "narratio.unknown", wantErr: "unsupported artifact source"},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got, err := NormalizeSessionArtifactSource(tt.source)
			if tt.wantErr != "" {
				if err == nil || !strings.Contains(err.Error(), tt.wantErr) {
					t.Fatalf("NormalizeSessionArtifactSource() error = %v, want contains %q", err, tt.wantErr)
				}
				return
			}
			if err != nil {
				t.Fatalf("NormalizeSessionArtifactSource() error = %v", err)
			}
			if got != tt.wantID {
				t.Fatalf("NormalizeSessionArtifactSource() = %q, want %q", got, tt.wantID)
			}
		})
	}
}

func TestResolveSessionArtifactPrefersManifestOutput(t *testing.T) {
	workspace := t.TempDir()
	paths := buildSessionPaths(workspace, "campaign", "session")
	if err := os.MkdirAll(paths.ArtifactsDir, 0o755); err != nil {
		t.Fatalf("MkdirAll() error = %v", err)
	}
	manifestPath := filepath.Join(paths.ArtifactsDir, "normalized.from-manifest.json")
	if err := os.WriteFile(manifestPath, []byte(`{"segments":[]}`), 0o644); err != nil {
		t.Fatalf("WriteFile() error = %v", err)
	}
	canonicalPath := filepath.Join(paths.TranscriptsDir, "normalized.json")
	if err := os.MkdirAll(filepath.Dir(canonicalPath), 0o755); err != nil {
		t.Fatalf("MkdirAll() error = %v", err)
	}
	if err := os.WriteFile(canonicalPath, []byte(`{"segments":[{"id":123}]}`), 0o644); err != nil {
		t.Fatalf("WriteFile() error = %v", err)
	}

	m := manifest.New("session", time.Now().UTC())
	m.MarkStageSucceeded("normalize", time.Now().UTC(), []manifest.ArtifactRecord{
		{Kind: "transcript_normalized", LocalPath: manifestPath, ProducerRunID: "run-123"},
	})

	resolved, err := ResolveSessionArtifact(paths, m, ArtifactTranscriptFull)
	if err != nil {
		t.Fatalf("ResolveSessionArtifact() error = %v", err)
	}
	if resolved.Path != manifestPath {
		t.Fatalf("resolved path = %q, want %q", resolved.Path, manifestPath)
	}
	if resolved.Provenance != "manifest.normalize.outputs" {
		t.Fatalf("provenance = %q, want manifest.normalize.outputs", resolved.Provenance)
	}
	if resolved.ProducerRunID != "run-123" {
		t.Fatalf("producer run id = %q, want run-123", resolved.ProducerRunID)
	}
}

func TestResolveSessionArtifactFallsBackToCanonicalPath(t *testing.T) {
	workspace := t.TempDir()
	paths := buildSessionPaths(workspace, "campaign", "session")
	canonicalPath := filepath.Join(paths.TranscriptsDir, "trimmed.json")
	if err := os.MkdirAll(filepath.Dir(canonicalPath), 0o755); err != nil {
		t.Fatalf("MkdirAll() error = %v", err)
	}
	if err := os.WriteFile(canonicalPath, []byte(`{"segments":[]}`), 0o644); err != nil {
		t.Fatalf("WriteFile() error = %v", err)
	}

	resolved, err := ResolveSessionArtifact(paths, nil, ArtifactTranscriptTrimmed)
	if err != nil {
		t.Fatalf("ResolveSessionArtifact() error = %v", err)
	}
	if resolved.Path != canonicalPath {
		t.Fatalf("resolved path = %q, want %q", resolved.Path, canonicalPath)
	}
	if resolved.Provenance != "fallback.canonical_path" {
		t.Fatalf("provenance = %q, want fallback.canonical_path", resolved.Provenance)
	}
}

func TestResolveSessionArtifactMissingReturnsTypedError(t *testing.T) {
	workspace := t.TempDir()
	paths := buildSessionPaths(workspace, "campaign", "session")

	_, err := ResolveSessionArtifact(paths, nil, ArtifactTranscriptTrimmed)
	if err == nil {
		t.Fatal("expected error, got nil")
	}
	if !errors.Is(err, ErrSessionArtifactNotFound) {
		t.Fatalf("errors.Is(err, ErrSessionArtifactNotFound) = false; err=%v", err)
	}
}

func TestResolveSessionArtifactValidatesTranscriptShape(t *testing.T) {
	workspace := t.TempDir()
	paths := buildSessionPaths(workspace, "campaign", "session")
	canonicalPath := filepath.Join(paths.TranscriptsDir, "processed.json")
	if err := os.MkdirAll(filepath.Dir(canonicalPath), 0o755); err != nil {
		t.Fatalf("MkdirAll() error = %v", err)
	}
	if err := os.WriteFile(canonicalPath, []byte(`{"not_segments":[]}`), 0o644); err != nil {
		t.Fatalf("WriteFile() error = %v", err)
	}

	_, err := ResolveSessionArtifact(paths, nil, ArtifactTranscriptPolished)
	if err == nil {
		t.Fatal("expected error, got nil")
	}
	if !strings.Contains(err.Error(), "top-level segments is required") {
		t.Fatalf("error = %q, want segments validation error", err.Error())
	}
}