package app

import (
	"context"
	"flag"
	"fmt"
	"io"
	"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/manifest"
)

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

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")
}

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

// Session dispatches session helper subcommands.
func Session(ctx context.Context, args []string, out io.Writer) error {
	if len(args) == 0 {
		return fmt.Errorf("session: expected subcommand: init|validate|status|plan|restore|artifacts|locks")
	}
	switch args[0] {
	case "init":
		return SessionInit(ctx, args[1:], out)
	case "validate":
		return SessionValidate(ctx, args[1:], out)
	case "status":
		return Status(ctx, args[1:], out)
	case "plan":
		return Plan(ctx, args[1:], out)
	case "restore":
		return Restore(ctx, args[1:], out)
	case "artifacts":
		return ArtifactsList(ctx, args[1:], out)
	case "locks":
		return SessionLocks(ctx, args[1:], out)
	default:
		return fmt.Errorf("session: unknown subcommand %q", args[0])
	}
}

// SessionLocks dispatches session-oriented publish lock list and mutation
// helpers while preserving the existing lock implementations.
func SessionLocks(ctx context.Context, args []string, out io.Writer) error {
	if len(args) > 0 && !isCLIFlagToken(args[0]) {
		switch args[0] {
		case "add":
			return LocksAdd(ctx, args[1:], out)
		case "remove":
			return LocksRemove(ctx, args[1:], out)
		}
	}
	return LocksList(ctx, args, out)
}

// Artifacts dispatches artifact helper subcommands.
func Artifacts(ctx context.Context, args []string, out io.Writer) error {
	if len(args) == 0 {
		return fmt.Errorf("artifacts: expected subcommand: list")
	}
	switch args[0] {
	case "list":
		return ArtifactsList(ctx, args[1:], out)
	default:
		return fmt.Errorf("artifacts: unknown subcommand %q", args[0])
	}
}

func loadHelperContext(ctx context.Context, flags commonConfigFlags, needStore bool) (*config.Config, storage.ObjectStore, *effectiveLocks, *manifest.Manifest, error) {
	cfg, err := loadCommandConfig(ctx, flags.pipelinePath, flags.campaignPath, flags.campaignFilePath, flags.sessionPath, flags.sessionOptions())
	if err != nil {
		return nil, nil, nil, nil, err
	}
	if err := config.Validate(cfg); err != nil {
		return nil, nil, nil, nil, err
	}
	var store storage.ObjectStore
	if needStore {
		store, err = newCommandObjectStore(ctx, cfg, nil)
		if err != nil {
			return nil, nil, nil, nil, err
		}
	} else {
		store, _ = objectStoreIfConfigured(ctx, cfg)
	}
	locks, err := loadEffectiveLocks(ctx, cfg, store)
	if err != nil {
		return 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, err
	}
	return cfg, store, locks, m, nil
}

func objectStoreIfConfigured(ctx context.Context, cfg *config.Config) (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 := newCommandObjectStore(ctx, cfg, nil)
	if err != nil {
		return nil, err
	}
	return store, nil
}