package app

import (
	"context"
	"fmt"
	"os"
	"path/filepath"
	"strings"

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

func runPostArchiveCleanup(ctx context.Context, env *Env, manifestPath string, m *manifest.Manifest, executed []string) error {
	if env == nil || env.Config == nil || env.Config.Pipeline == nil || m == nil {
		return nil
	}

	spoolRequested := env.Config.Pipeline.Spool.DeleteAudioAfterArchive
	workRequested := env.Config.Pipeline.Workspace.CleanupAfterArchive
	if !spoolRequested && !workRequested {
		return nil
	}

	sr := archiveStageRecordForCleanup(m, executed)
	if sr == nil {
		return nil
	}
	if sr.Metadata == nil {
		sr.Metadata = map[string]any{}
	}
	sr.Metadata["spool_cleanup_requested"] = spoolRequested
	sr.Metadata["workdir_cleanup_requested"] = workRequested

	eligible, reason := archiveCleanupEligible(env.Config, sr)
	if !eligible {
		sr.Metadata["cleanup_skipped"] = true
		sr.Metadata["cleanup_skipped_reason"] = reason
		if err := env.ManifestStore.Save(ctx, manifestPath, m); err != nil {
			return fmt.Errorf("save manifest cleanup skip metadata %q: %w", manifestPath, err)
		}
		return nil
	}

	spoolDir := strings.TrimSpace(m.LocalSpoolDir)
	if spoolDir == "" {
		spoolDir = artifacts.SessionSpoolAudioDir(
			env.Config.Pipeline.Spool.Root,
			strings.TrimSpace(env.Config.Session.Campaign),
			strings.TrimSpace(env.Config.Session.SessionID),
			strings.TrimSpace(m.RunID),
		)
	}
	workDir := strings.TrimSpace(m.LocalWorkDir)
	if workDir == "" {
		workDir = artifacts.SessionRunRootForCampaign(
			env.Config.Pipeline.Workspace.Root,
			strings.TrimSpace(env.Config.Session.Campaign),
			strings.TrimSpace(env.Config.Session.SessionID),
			strings.TrimSpace(m.RunID),
		)
	}

	if spoolRequested {
		if err := removeRunScopedDir(strings.TrimSpace(env.Config.Pipeline.Spool.Root), spoolDir, "pipeline.spool.delete_audio_after_archive"); err != nil {
			sr.Metadata["cleanup_failed"] = true
			sr.Metadata["cleanup_failed_policy"] = "pipeline.spool.delete_audio_after_archive"
			sr.Metadata["cleanup_failed_path"] = spoolDir
			_ = env.ManifestStore.Save(ctx, manifestPath, m)
			return err
		}
		sr.Metadata["spool_cleanup_deleted"] = filepath.Clean(spoolDir)
	}

	if !workRequested {
		sr.Metadata["cleanup_completed"] = true
		sr.Metadata["cleanup_skipped"] = false
		if err := env.ManifestStore.Save(ctx, manifestPath, m); err != nil {
			return fmt.Errorf("save manifest cleanup metadata %q: %w", manifestPath, err)
		}
		return nil
	}

	if err := removeRunScopedDir(strings.TrimSpace(env.Config.Pipeline.Workspace.Root), workDir, "pipeline.workspace.cleanup_after_archive"); err != nil {
		sr.Metadata["cleanup_failed"] = true
		sr.Metadata["cleanup_failed_policy"] = "pipeline.workspace.cleanup_after_archive"
		sr.Metadata["cleanup_failed_path"] = workDir
		_ = env.ManifestStore.Save(ctx, manifestPath, m)
		return err
	}

	sr.Metadata["workdir_cleanup_deleted"] = filepath.Clean(workDir)
	sr.Metadata["cleanup_completed"] = true
	sr.Metadata["cleanup_skipped"] = false
	return nil
}

func archiveStageRecordForCleanup(m *manifest.Manifest, executed []string) *manifest.StageRecord {
	if m == nil {
		return nil
	}
	archiveRan := false
	for _, name := range executed {
		if name == "archive" {
			archiveRan = true
			break
		}
	}
	if !archiveRan {
		return nil
	}
	sr := m.Stages["archive"]
	if sr == nil || sr.Status != manifest.StatusSucceeded {
		return nil
	}
	return sr
}

func archiveCleanupEligible(cfg *config.Config, sr *manifest.StageRecord) (bool, string) {
	if cfg == nil || cfg.Pipeline == nil || cfg.Pipeline.Archive == nil {
		return false, "archive configuration is missing"
	}
	enabled := true
	if cfg.Pipeline.Archive.Enabled != nil {
		enabled = *cfg.Pipeline.Archive.Enabled
	}
	if !enabled {
		return false, "archive.enabled is false"
	}
	uploadRun := true
	if cfg.Pipeline.Archive.UploadRun != nil {
		uploadRun = *cfg.Pipeline.Archive.UploadRun
	}
	if !uploadRun {
		return false, "archive.upload_run is false"
	}
	if sr == nil || sr.Metadata == nil {
		return false, "archive metadata is missing"
	}
	if skipped, _ := sr.Metadata["skipped"].(bool); skipped {
		return false, "archive stage was skipped"
	}
	if uploaded, _ := sr.Metadata["uploaded"].(bool); !uploaded {
		return false, "archive did not upload run record"
	}
	if pointer, _ := sr.Metadata["current_pointer_written"].(bool); !pointer {
		return false, "archive did not write current pointer"
	}
	if strings.TrimSpace(asString(sr.Metadata["current_run_id_key"])) == "" {
		return false, "archive current run pointer key is missing"
	}
	return true, ""
}

func removeRunScopedDir(root, target, policy string) error {
	cleanRoot := strings.TrimSpace(root)
	cleanTarget := strings.TrimSpace(target)
	if cleanRoot == "" {
		return fmt.Errorf("cleanup policy %s: root path is required", policy)
	}
	if cleanTarget == "" {
		return fmt.Errorf("cleanup policy %s: target path is required", policy)
	}

	rootAbs, err := filepath.Abs(cleanRoot)
	if err != nil {
		return fmt.Errorf("cleanup policy %s: resolve root %q: %w", policy, cleanRoot, err)
	}
	targetAbs, err := filepath.Abs(cleanTarget)
	if err != nil {
		return fmt.Errorf("cleanup policy %s: resolve target %q: %w", policy, cleanTarget, err)
	}

	rel, err := filepath.Rel(rootAbs, targetAbs)
	if err != nil {
		return fmt.Errorf("cleanup policy %s: relative path from %q to %q: %w", policy, rootAbs, targetAbs, err)
	}
	if rel == "." {
		return fmt.Errorf("cleanup policy %s: refusing to delete root directory %q", policy, rootAbs)
	}
	if rel == ".." || strings.HasPrefix(rel, ".."+string(filepath.Separator)) {
		return fmt.Errorf("cleanup policy %s: refusing to delete path outside root: root=%q target=%q", policy, rootAbs, targetAbs)
	}

	info, err := os.Lstat(targetAbs)
	if err != nil {
		if os.IsNotExist(err) {
			return nil
		}
		return fmt.Errorf("cleanup policy %s: stat target %q: %w", policy, targetAbs, err)
	}
	if info.Mode()&os.ModeSymlink != 0 {
		return fmt.Errorf("cleanup policy %s: refusing to delete symlink path %q", policy, targetAbs)
	}
	if !info.IsDir() {
		return fmt.Errorf("cleanup policy %s: target %q is not a directory", policy, targetAbs)
	}
	if err := os.RemoveAll(targetAbs); err != nil {
		return fmt.Errorf("cleanup policy %s: remove %q: %w", policy, targetAbs, err)
	}
	return nil
}

func asString(v any) string {
	s, _ := v.(string)
	return s
}