package state

import (
	"context"
	"encoding/json"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"gitea.maximumdirect.net/eric/weatherreporter/internal/briefing"
	"gitea.maximumdirect.net/eric/weatherreporter/internal/config"
	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
	"gitea.maximumdirect.net/eric/weatherreporter/internal/promptinput"
	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
)

func TestPathsUseRunIDAndWorkspace(t *testing.T) {
	store := newTestStore(t)
	resolved := resolveDailyAt(t, "2026-05-29T05:00:00-05:00")

	paths, err := store.Paths(resolved)
	if err != nil {
		t.Fatalf("Paths() error = %v", err)
	}

	for _, want := range []string{
		filepath.Join("snapshots", "daily", "2026-05-29", "20260529T100000.000000000Z_daily_today.modules.json"),
		filepath.Join("snapshots", "daily", "2026-05-29", "20260529T100000.000000000Z_daily_today.metadata.json"),
		filepath.Join("data-packages", "daily", "2026-05-29", "20260529T100000.000000000Z_daily_today.data_package.yaml"),
		filepath.Join("preflight", "daily", "2026-05-29", "20260529T100000.000000000Z_daily_today.render.json"),
		filepath.Join("notifications", "daily", "2026-05-29", "20260529T100000.000000000Z_daily_today.distributor.json"),
		filepath.Join("reports", "daily", "20260529T100000.000000000Z_daily_today.md"),
	} {
		if !strings.Contains(pathsString(paths), want) {
			t.Fatalf("paths = %#v, want component %q", paths, want)
		}
	}
}

func TestSaveArtifactsAndMetadataRoundTrip(t *testing.T) {
	store := newTestStore(t)
	resolved := resolveDailyAt(t, "2026-05-29T05:00:00-05:00")
	briefingMetadata := stateBriefingMetadata(resolved)
	snapshot, err := module.NewSnapshot([]module.Output{{ID: module.Metadata, StanzaName: "metadata", Value: map[string]string{"run_id": resolved.Metadata().RunID}}})
	if err != nil {
		t.Fatalf("NewSnapshot() error = %v", err)
	}
	dataPackage, err := promptinput.Build(promptinput.BuildRequest{
		Metadata: promptinput.Metadata{
			RunID:       resolved.Metadata().RunID,
			ReportID:    resolved.Definition.ID,
			Variant:     briefingMetadata.Variant,
			PromptID:    resolved.Definition.PromptID,
			GeneratedAt: resolved.GeneratedAt,
			Timezone:    resolved.Timezone,
			ValidPeriod: resolved.ValidPeriod,
		},
		Modules: snapshot,
	})
	if err != nil {
		t.Fatalf("Build() error = %v", err)
	}

	dataPackagePath, err := store.SaveDataPackage(context.Background(), resolved, dataPackage)
	if err != nil {
		t.Fatalf("SaveDataPackage() error = %v", err)
	}
	moduleSnapshotPath, err := store.SaveModuleSnapshot(context.Background(), resolved, snapshot)
	if err != nil {
		t.Fatalf("SaveModuleSnapshot() error = %v", err)
	}
	preflightPath, err := store.SavePreflight(context.Background(), resolved, PreflightArtifact{Stdout: `{"ok":true}`})
	if err != nil {
		t.Fatalf("SavePreflight() error = %v", err)
	}
	notificationPath, err := store.SaveDistributorNotification(context.Background(), resolved, DistributorNotificationArtifact{
		RunID:          resolved.Metadata().RunID,
		ReportID:       resolved.Definition.ID,
		AttemptedAt:    resolved.GeneratedAt,
		Endpoint:       "https://distributor.example.test",
		PipelineID:     "weatherreporter.daily",
		BundleID:       "weatherreporter.home.daily.run",
		IdempotencyKey: "weatherreporter.home.daily.run",
		SourcePath:     "/tmp/report.md",
		BundlePaths:    []string{"2026-05-29/daily/report.md"},
		BundleCreated:  resolved.GeneratedAt,
		Status:         "succeeded",
		RunStatus:      &DistributorRunStatus{RunID: "distributor-run", Status: "succeeded"},
	})
	if err != nil {
		t.Fatalf("SaveDistributorNotification() error = %v", err)
	}
	renderedReportPath, err := store.PrepareRenderedReport(context.Background(), resolved)
	if err != nil {
		t.Fatalf("PrepareRenderedReport() error = %v", err)
	}
	if err := os.WriteFile(renderedReportPath, []byte("# Daily Report\n"), 0o600); err != nil {
		t.Fatalf("write rendered report: %v", err)
	}
	var preflight PreflightArtifact
	preflightData, err := os.ReadFile(preflightPath)
	if err != nil {
		t.Fatalf("read preflight: %v", err)
	}
	if err := json.Unmarshal(preflightData, &preflight); err != nil {
		t.Fatalf("decode preflight: %v", err)
	}
	if preflight.Stdout != `{"ok":true}` {
		t.Fatalf("preflight stdout = %q, want render stdout", preflight.Stdout)
	}
	var notification DistributorNotificationArtifact
	notificationData, err := os.ReadFile(notificationPath)
	if err != nil {
		t.Fatalf("read notification: %v", err)
	}
	if err := json.Unmarshal(notificationData, &notification); err != nil {
		t.Fatalf("decode notification: %v", err)
	}
	if notification.SchemaVersion != DistributorNotificationSchemaVersion || notification.PipelineID != "weatherreporter.daily" || len(notification.BundlePaths) != 1 || notification.RunStatus == nil || notification.RunStatus.Status != "succeeded" {
		t.Fatalf("notification = %#v, want persisted distributor status", notification)
	}
	paths, err := store.Paths(resolved)
	if err != nil {
		t.Fatalf("Paths() error = %v", err)
	}
	metadata := BuildMetadataFromBriefingMetadata(resolved, briefingMetadata, ArtifactPaths{
		ModuleSnapshot: moduleSnapshotPath,
		Metadata:       paths.Metadata,
		DataPackage:    dataPackagePath,
		Preflight:      preflightPath,
		RenderedReport: renderedReportPath,
	})
	metadataPath, err := store.SaveMetadata(context.Background(), metadata)
	if err != nil {
		t.Fatalf("SaveMetadata() error = %v", err)
	}

	for _, path := range []string{moduleSnapshotPath, dataPackagePath, preflightPath, notificationPath, renderedReportPath, metadataPath} {
		if _, err := os.Stat(path); err != nil {
			t.Fatalf("expected artifact %q: %v", path, err)
		}
	}
	loadedSnapshot, err := store.LoadModuleSnapshot(context.Background(), moduleSnapshotPath)
	if err != nil {
		t.Fatalf("LoadModuleSnapshot() error = %v", err)
	}
	if loadedSnapshot.SchemaVersion != module.SnapshotSchemaVersion || len(loadedSnapshot.Outputs) != 1 {
		t.Fatalf("loaded module snapshot = %#v, want one metadata output", loadedSnapshot)
	}
	loadedDataPackage, err := store.LoadDataPackage(context.Background(), dataPackagePath)
	if err != nil {
		t.Fatalf("LoadDataPackage() error = %v", err)
	}
	if loadedDataPackage.SchemaVersion != promptinput.SchemaVersion || loadedDataPackage.Briefing.Order[0] != "metadata" {
		t.Fatalf("loaded data package = %#v, want YAML package with metadata stanza", loadedDataPackage)
	}
	var decoded Metadata
	data, err := os.ReadFile(metadataPath)
	if err != nil {
		t.Fatalf("read metadata: %v", err)
	}
	if err := json.Unmarshal(data, &decoded); err != nil {
		t.Fatalf("decode metadata: %v", err)
	}
	if decoded.RunID != resolved.Metadata().RunID {
		t.Fatalf("RunID = %q, want %q", decoded.RunID, resolved.Metadata().RunID)
	}
	if decoded.ModuleSnapshotPath != moduleSnapshotPath || decoded.DataPackagePath != dataPackagePath || decoded.PreflightPath != preflightPath {
		t.Fatalf("metadata paths = %#v, want saved artifact paths", decoded)
	}
	if decoded.RenderedReportPath != renderedReportPath {
		t.Fatalf("RenderedReportPath = %q, want %q", decoded.RenderedReportPath, renderedReportPath)
	}
	if decoded.Location == nil || decoded.Location.Name != "Brentwood" || decoded.Location.Timezone != "America/Chicago" {
		t.Fatalf("metadata location = %#v, want briefing location", decoded.Location)
	}
	if strings.Contains(string(data), "MetadataPath") || strings.Contains(string(data), "metadataPath") {
		t.Fatalf("metadata JSON includes runtime-only MetadataPath:\n%s", string(data))
	}
}

func TestSaveMetadataUsesExplicitMetadataPath(t *testing.T) {
	store := newTestStore(t)
	resolved := resolveDailyAt(t, "2026-05-29T05:00:00-05:00")
	briefingMetadata := stateBriefingMetadata(resolved)
	paths, err := store.Paths(resolved)
	if err != nil {
		t.Fatalf("Paths() error = %v", err)
	}
	otherDir := filepath.Join(t.TempDir(), "other-artifacts")
	derivedMetadataPath := filepath.Join(otherDir, resolved.Metadata().RunID+".metadata.json")

	metadata := BuildMetadataFromBriefingMetadata(resolved, briefingMetadata, ArtifactPaths{
		ModuleSnapshot: paths.ModuleSnapshot,
		Metadata:       paths.Metadata,
		DataPackage:    paths.DataPackage,
		Preflight:      paths.Preflight,
		RenderedReport: paths.RenderedReport,
	})
	metadataPath, err := store.SaveMetadata(context.Background(), metadata)
	if err != nil {
		t.Fatalf("SaveMetadata() error = %v", err)
	}
	if metadataPath != paths.Metadata {
		t.Fatalf("SaveMetadata() path = %q, want explicit metadata path %q", metadataPath, paths.Metadata)
	}
	if _, err := os.Stat(paths.Metadata); err != nil {
		t.Fatalf("expected explicit metadata path %q: %v", paths.Metadata, err)
	}
	if _, err := os.Stat(derivedMetadataPath); !os.IsNotExist(err) {
		t.Fatalf("derived metadata path stat error = %v, want not exist", err)
	}
}

func TestFindPriorSnapshot(t *testing.T) {
	store := newTestStore(t)
	first := resolveDailyAt(t, "2026-05-29T05:00:00-05:00")
	second := resolveDailyAt(t, "2026-05-29T08:00:00-05:00")
	paths := savePriorMetadata(t, store, first, stateBriefingMetadata(first))

	prior, err := store.FindPriorSnapshot(context.Background(), second)
	if err != nil {
		t.Fatalf("FindPriorSnapshot() error = %v", err)
	}
	if prior == nil {
		t.Fatal("FindPriorSnapshot() = nil, want prior snapshot")
	}
	if prior.Metadata.RunID != first.Metadata().RunID {
		t.Fatalf("RunID = %q, want %q", prior.Metadata.RunID, first.Metadata().RunID)
	}
	if prior.ModuleSnapshotPath != paths.ModuleSnapshot {
		t.Fatalf("ModuleSnapshotPath = %q, want %q", prior.ModuleSnapshotPath, paths.ModuleSnapshot)
	}
}

func TestFindPriorSnapshotUsesValidDate(t *testing.T) {
	store := newTestStore(t)
	previousDate := resolveDailyAt(t, "2026-05-28T05:00:00-05:00")
	currentDate := resolveDailyAt(t, "2026-05-29T05:00:00-05:00")
	savePriorMetadata(t, store, previousDate, stateBriefingMetadata(previousDate))

	prior, err := store.FindPriorSnapshot(context.Background(), currentDate)
	if err != nil {
		t.Fatalf("FindPriorSnapshot() error = %v", err)
	}
	if prior != nil {
		t.Fatalf("FindPriorSnapshot() = %#v, want nil for different valid date", prior)
	}
}

func TestFindPriorSnapshotSupportsThreeDay(t *testing.T) {
	store := newTestStore(t)
	first := resolveThreeDayAt(t, "2026-05-29T05:00:00-05:00")
	second := resolveThreeDayAt(t, "2026-05-29T08:00:00-05:00")
	savePriorMetadata(t, store, first, stateBriefingMetadata(first))

	prior, err := store.FindPriorSnapshot(context.Background(), second)
	if err != nil {
		t.Fatalf("FindPriorSnapshot() error = %v", err)
	}
	if prior == nil {
		t.Fatal("FindPriorSnapshot() = nil, want prior 3-day snapshot")
	}
	if prior.Metadata.RunID != first.Metadata().RunID {
		t.Fatalf("RunID = %q, want %q", prior.Metadata.RunID, first.Metadata().RunID)
	}
}

func TestFindPriorSnapshotSupportsWeekend(t *testing.T) {
	store := newTestStore(t)
	first := resolveWeekendAt(t, "2026-05-29T05:00:00-05:00")
	second := resolveWeekendAt(t, "2026-05-29T08:00:00-05:00")
	savePriorMetadata(t, store, first, stateBriefingMetadata(first))

	prior, err := store.FindPriorSnapshot(context.Background(), second)
	if err != nil {
		t.Fatalf("FindPriorSnapshot() error = %v", err)
	}
	if prior == nil {
		t.Fatal("FindPriorSnapshot() = nil, want prior weekend snapshot")
	}
	if prior.Metadata.RunID != first.Metadata().RunID {
		t.Fatalf("RunID = %q, want %q", prior.Metadata.RunID, first.Metadata().RunID)
	}
}

func TestFindPriorSnapshotSupportsNarrowedWeekendPeriod(t *testing.T) {
	store := newTestStore(t)
	first := resolveWeekendAt(t, "2026-05-29T19:00:00-05:00")
	second := resolveWeekendAt(t, "2026-05-30T08:00:00-05:00")
	savePriorMetadata(t, store, first, stateBriefingMetadata(first))

	prior, err := store.FindPriorSnapshot(context.Background(), second)
	if err != nil {
		t.Fatalf("FindPriorSnapshot() error = %v", err)
	}
	if prior == nil {
		t.Fatal("FindPriorSnapshot() = nil, want prior narrowed weekend snapshot")
	}
	if prior.Metadata.RunID != first.Metadata().RunID {
		t.Fatalf("RunID = %q, want %q", prior.Metadata.RunID, first.Metadata().RunID)
	}
}

func TestFindPriorSnapshotIgnoresRollingWindowReports(t *testing.T) {
	store := newTestStore(t)
	first := resolveHourlyAt(t, "2026-05-29T05:00:00-05:00")
	second := resolveHourlyAt(t, "2026-05-29T06:00:00-05:00")
	savePriorMetadata(t, store, first, stateBriefingMetadata(first))

	prior, err := store.FindPriorSnapshot(context.Background(), second)
	if err != nil {
		t.Fatalf("FindPriorSnapshot() error = %v", err)
	}
	if prior != nil {
		t.Fatalf("FindPriorSnapshot() = %#v, want nil for rolling-window comparison", prior)
	}
}

func TestFilesystemStoreRejectsUnsafeDirs(t *testing.T) {
	cfg := config.Defaults().Workspace
	cfg.Root = t.TempDir()
	cfg.SnapshotsDir = "../snapshots"

	_, err := NewFilesystemStore(cfg)
	if err == nil {
		t.Fatal("NewFilesystemStore() error = nil, want unsafe path error")
	}
	if !strings.Contains(err.Error(), "within workspace root") {
		t.Fatalf("error = %q, want path safety context", err.Error())
	}
}

func newTestStore(t *testing.T) *FilesystemStore {
	t.Helper()
	cfg := config.Defaults().Workspace
	cfg.Root = t.TempDir()
	store, err := NewFilesystemStore(cfg)
	if err != nil {
		t.Fatalf("NewFilesystemStore() error = %v", err)
	}
	return store
}

func resolveDailyAt(t *testing.T, value string) report.Resolved {
	t.Helper()
	location, err := timeutil.LoadLocation("America/Chicago")
	if err != nil {
		t.Fatalf("LoadLocation() error = %v", err)
	}
	now, err := time.Parse(time.RFC3339, value)
	if err != nil {
		t.Fatalf("parse time: %v", err)
	}
	resolved, err := report.DefaultRegistry().Resolve(report.DailyToday, report.ResolveRequest{
		Now:      now,
		Location: location,
	})
	if err != nil {
		t.Fatalf("Resolve() error = %v", err)
	}
	return resolved
}

func resolveThreeDayAt(t *testing.T, value string) report.Resolved {
	t.Helper()
	location, err := timeutil.LoadLocation("America/Chicago")
	if err != nil {
		t.Fatalf("LoadLocation() error = %v", err)
	}
	now, err := time.Parse(time.RFC3339, value)
	if err != nil {
		t.Fatalf("parse time: %v", err)
	}
	resolved, err := report.DefaultRegistry().Resolve(report.ThreeDay, report.ResolveRequest{
		Now:      now,
		Location: location,
	})
	if err != nil {
		t.Fatalf("Resolve() error = %v", err)
	}
	return resolved
}

func resolveWeekendAt(t *testing.T, value string) report.Resolved {
	t.Helper()
	location, err := timeutil.LoadLocation("America/Chicago")
	if err != nil {
		t.Fatalf("LoadLocation() error = %v", err)
	}
	now, err := time.Parse(time.RFC3339, value)
	if err != nil {
		t.Fatalf("parse time: %v", err)
	}
	resolved, err := report.DefaultRegistry().Resolve(report.Weekend, report.ResolveRequest{
		Now:      now,
		Location: location,
	})
	if err != nil {
		t.Fatalf("Resolve() error = %v", err)
	}
	return resolved
}

func resolveHourlyAt(t *testing.T, value string) report.Resolved {
	t.Helper()
	location, err := timeutil.LoadLocation("America/Chicago")
	if err != nil {
		t.Fatalf("LoadLocation() error = %v", err)
	}
	now, err := time.Parse(time.RFC3339, value)
	if err != nil {
		t.Fatalf("parse time: %v", err)
	}
	resolved, err := report.DefaultRegistry().Resolve(report.Hourly, report.ResolveRequest{
		Now:      now,
		Location: location,
	})
	if err != nil {
		t.Fatalf("Resolve() error = %v", err)
	}
	return resolved
}

func stateBriefingMetadata(resolved report.Resolved) briefing.Metadata {
	return briefing.Metadata{
		RunID:       resolved.Metadata().RunID,
		ReportID:    resolved.Definition.ID,
		Variant:     "today",
		PromptID:    resolved.Definition.PromptID,
		GeneratedAt: resolved.GeneratedAt,
		Units:       "us",
		Timezone:    resolved.Timezone,
		Location: &briefing.LocationContext{
			ID:       "home",
			Name:     "Brentwood",
			Region:   "St. Louis Metro",
			Timezone: resolved.Timezone,
		},
		ValidPeriod: resolved.ValidPeriod,
	}
}

func savePriorMetadata(t *testing.T, store *FilesystemStore, resolved report.Resolved, metadata briefing.Metadata) ArtifactPaths {
	t.Helper()
	paths, err := store.Paths(resolved)
	if err != nil {
		t.Fatalf("Paths() error = %v", err)
	}
	_, err = store.SaveMetadata(context.Background(), BuildMetadataFromBriefingMetadata(resolved, metadata, ArtifactPaths{
		ModuleSnapshot: paths.ModuleSnapshot,
		Metadata:       paths.Metadata,
		DataPackage:    paths.DataPackage,
		Preflight:      paths.Preflight,
		RenderedReport: paths.RenderedReport,
	}))
	if err != nil {
		t.Fatalf("SaveMetadata() error = %v", err)
	}
	return paths
}

func pathsString(paths ArtifactPaths) string {
	return strings.Join([]string{
		paths.Metadata,
		paths.ModuleSnapshot,
		paths.DataPackage,
		paths.Preflight,
		paths.Notification,
		paths.RenderedReport,
	}, "\n")
}