package app

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

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

type commonConfigFlags struct {
	pipelinePath      string
	campaignPath      string
	campaignFilePath  string
	sessionPath       string
	sessionID         string
	previousSessionID string
	profile           singletonStringFlag
	secretsDir        singletonStringFlag
}

func addCommonConfigFlags(fs *flag.FlagSet, flags *commonConfigFlags) {
	fs.StringVar(&flags.pipelinePath, "config", "", "path to pipeline.yml (optional; defaults searched)")
	fs.StringVar(&flags.campaignPath, "campaign", "", "campaign ID")
	fs.StringVar(&flags.campaignFilePath, "campaign-file", "", "path to campaign.yml")
	fs.StringVar(&flags.sessionPath, "session", "", "path to session.yml")
	fs.StringVar(&flags.sessionID, "session-id", "", "session identifier")
	fs.StringVar(&flags.previousSessionID, "previous-session-id", "", "expected previous session identifier")
	flags.profile.name = "profile"
	fs.Var(&flags.profile, "profile", "named pipeline profile")
	flags.secretsDir.name = "secrets-dir"
	fs.Var(&flags.secretsDir, "secrets-dir", "secrets directory (optional; defaults beside pipeline.yml)")
}

func (f commonConfigFlags) sessionOptions() config.SessionLoadOptions {
	return config.SessionLoadOptions{
		SessionID:         f.sessionID,
		PreviousSessionID: f.previousSessionID,
		Profile:           f.profile.pointer(),
	}
}

// Session dispatches session helper subcommands.
func Session(ctx context.Context, args []string, out io.Writer) error {
	return sessionWithDependencies(ctx, args, out, commandDependencies{})
}

func sessionWithDependencies(ctx context.Context, args []string, out io.Writer, deps commandDependencies) error {
	deps = normalizeCommandDependencies(deps)
	if len(args) == 0 {
		return fmt.Errorf("session: expected subcommand: init|validate|status|plan|restore|artifacts|locks")
	}
	switch args[0] {
	case "init":
		return sessionInitWithDependencies(ctx, args[1:], out, deps)
	case "validate":
		return sessionValidateWithDependencies(ctx, args[1:], out, deps)
	case "status":
		return statusWithDependencies(ctx, args[1:], out, deps)
	case "plan":
		return planWithDependencies(ctx, args[1:], out, deps)
	case "restore":
		return restoreWithDependencies(ctx, args[1:], out, deps)
	case "artifacts":
		return artifactsListWithDependencies(ctx, args[1:], out, deps)
	case "locks":
		return sessionLocksWithDependencies(ctx, args[1:], out, deps)
	default:
		return fmt.Errorf("session: unknown subcommand %q", args[0])
	}
}

// SessionLocks dispatches session-oriented publish lock list and mutation
// helpers.
func SessionLocks(ctx context.Context, args []string, out io.Writer) error {
	return sessionLocksWithDependencies(ctx, args, out, commandDependencies{})
}

func sessionLocksWithDependencies(ctx context.Context, args []string, out io.Writer, deps commandDependencies) error {
	if len(args) > 0 && !isCLIFlagToken(args[0]) {
		switch args[0] {
		case "add":
			return locksAddWithDependencies(ctx, args[1:], out, deps)
		case "remove":
			return locksRemoveWithDependencies(ctx, args[1:], out, deps)
		}
	}
	return locksListWithDependencies(ctx, args, out, deps)
}

// Artifacts dispatches artifact helper subcommands.
func Artifacts(ctx context.Context, args []string, out io.Writer) error {
	return artifactsWithDependencies(ctx, args, out, commandDependencies{})
}

func artifactsWithDependencies(ctx context.Context, args []string, out io.Writer, deps commandDependencies) error {
	if len(args) == 0 {
		return fmt.Errorf("artifacts: expected subcommand: list")
	}
	switch args[0] {
	case "list":
		return artifactsListWithDependencies(ctx, args[1:], out, deps)
	default:
		return fmt.Errorf("artifacts: unknown subcommand %q", args[0])
	}
}

func loadHelperContextWithDependencies(ctx context.Context, flags commonConfigFlags, needStore bool, deps commandDependencies) (*config.Config, storage.ObjectStore, []artifacts.RemoteLock, *manifest.Manifest, func(), error) {
	deps = normalizeCommandDependencies(deps)
	loaded, err := loadCommandConfigWithDependencies(ctx, flags.pipelinePath, flags.campaignPath, flags.campaignFilePath, flags.sessionPath, flags.sessionOptions(), flags.secretsDir.pointer(), deps)
	if err != nil {
		return nil, nil, nil, nil, nil, err
	}
	release := true
	defer func() {
		if release {
			_ = loaded.Close()
		}
	}()
	cfg := loaded.Config
	if err := config.Validate(cfg); err != nil {
		return nil, nil, nil, nil, nil, err
	}
	var store storage.ObjectStore
	if needStore {
		store, err = newCommandObjectStoreWithDependencies(ctx, cfg, nil, deps)
		if err != nil {
			return nil, nil, nil, nil, nil, err
		}
	} else {
		store, _ = objectStoreIfConfiguredWithDependencies(ctx, cfg, deps)
	}
	var locks []artifacts.RemoteLock
	if store != nil {
		sessionPrefix, prefixErr := artifacts.ResolvePublishSessionPrefix(cfg, nil)
		if prefixErr != nil {
			return nil, nil, nil, nil, nil, prefixErr
		}
		locks, err = artifacts.ListRemoteLocks(ctx, store, sessionPrefix)
		if err != nil {
			return nil, nil, nil, nil, nil, err
		}
	}
	paths := artifacts.NewLocalStore(cfg.Pipeline.Workspace.Root).SessionPathsFor(cfg.Session.Campaign, cfg.Session.SessionID)
	m, err := loadLocalManifest(ctx, paths.ManifestPath)
	if err != nil {
		return nil, nil, nil, nil, nil, err
	}
	release = false
	return cfg, store, locks, m, func() { _ = loaded.Close() }, nil
}

func objectStoreIfConfiguredWithDependencies(ctx context.Context, cfg *config.Config, deps commandDependencies) (storage.ObjectStore, error) {
	if cfg == nil || cfg.Pipeline == nil || cfg.Pipeline.Storage.S3 == nil || strings.TrimSpace(cfg.Pipeline.Storage.S3.Bucket) == "" {
		return nil, nil
	}
	store, err := newCommandObjectStoreWithDependencies(ctx, cfg, nil, deps)
	if err != nil {
		return nil, err
	}
	return store, nil
}

func writeLocalFile(path string, data []byte, force bool) error {
	cleaned := filepath.Clean(strings.TrimSpace(path))
	if cleaned == "" || cleaned == "." {
		return fmt.Errorf("output path is required")
	}
	if !force {
		if _, err := os.Stat(cleaned); err == nil {
			return fmt.Errorf("output file %q already exists; pass --force to overwrite", cleaned)
		} else if err != nil && !os.IsNotExist(err) {
			return fmt.Errorf("check output file %q: %w", cleaned, err)
		}
	}
	if err := fileops.EnsureWorkspaceDirectory(filepath.Dir(cleaned)); err != nil {
		return fmt.Errorf("create output directory: %w", err)
	}
	if err := os.WriteFile(cleaned, data, fileops.WorkspaceFileMode); err != nil {
		return err
	}
	return os.Chmod(cleaned, fileops.WorkspaceFileMode)
}