package cmd

import (
	"encoding/json"
	"fmt"
	"os"
	"path/filepath"

	"github.com/spf13/cobra"
	"github.com/steveyegge/gastown/internal/config"
	"github.com/steveyegge/gastown/internal/git"
	"github.com/steveyegge/gastown/internal/refinery"
	"github.com/steveyegge/gastown/internal/rig"
	"github.com/steveyegge/gastown/internal/style"
	"github.com/steveyegge/gastown/internal/tmux"
	"github.com/steveyegge/gastown/internal/workspace"
)

// Refinery command flags
var (
	refineryForeground bool
	refineryStatusJSON bool
	refineryQueueJSON  bool
)

var refineryCmd = &cobra.Command{
	Use:     "refinery",
	Aliases: []string{"ref"},
	Short:   "Manage the merge queue processor",
	Long: `Manage the Refinery merge queue processor for a rig.

The Refinery processes merge requests from polecats, merging their work
into integration branches and ultimately to main.`,
}

var refineryStartCmd = &cobra.Command{
	Use:   "start <rig>",
	Short: "Start the refinery",
	Long: `Start the Refinery for a rig.

Launches the merge queue processor which monitors for polecat work branches
and merges them to the appropriate target branches.

Examples:
  gt refinery start gastown
  gt refinery start gastown --foreground`,
	Args: cobra.ExactArgs(1),
	RunE: runRefineryStart,
}

var refineryStopCmd = &cobra.Command{
	Use:   "stop <rig>",
	Short: "Stop the refinery",
	Long: `Stop a running Refinery.

Gracefully stops the refinery, completing any in-progress merge first.`,
	Args: cobra.ExactArgs(1),
	RunE: runRefineryStop,
}

var refineryStatusCmd = &cobra.Command{
	Use:   "status <rig>",
	Short: "Show refinery status",
	Long: `Show the status of a rig's Refinery.

Displays running state, current work, queue length, and statistics.`,
	Args: cobra.ExactArgs(1),
	RunE: runRefineryStatus,
}

var refineryQueueCmd = &cobra.Command{
	Use:   "queue <rig>",
	Short: "Show merge queue",
	Long: `Show the merge queue for a rig.

Lists all pending merge requests waiting to be processed.`,
	Args: cobra.ExactArgs(1),
	RunE: runRefineryQueue,
}

var refineryAttachCmd = &cobra.Command{
	Use:   "attach <rig>",
	Short: "Attach to refinery session",
	Long: `Attach to a running Refinery's Claude session.

Allows interactive access to the Refinery agent for debugging
or manual intervention.

Examples:
  gt refinery attach gastown`,
	Args: cobra.ExactArgs(1),
	RunE: runRefineryAttach,
}

func init() {
	// Start flags
	refineryStartCmd.Flags().BoolVar(&refineryForeground, "foreground", false, "Run in foreground (default: background)")

	// Status flags
	refineryStatusCmd.Flags().BoolVar(&refineryStatusJSON, "json", false, "Output as JSON")

	// Queue flags
	refineryQueueCmd.Flags().BoolVar(&refineryQueueJSON, "json", false, "Output as JSON")

	// Add subcommands
	refineryCmd.AddCommand(refineryStartCmd)
	refineryCmd.AddCommand(refineryStopCmd)
	refineryCmd.AddCommand(refineryStatusCmd)
	refineryCmd.AddCommand(refineryQueueCmd)
	refineryCmd.AddCommand(refineryAttachCmd)

	rootCmd.AddCommand(refineryCmd)
}

// getRefineryManager creates a refinery manager for a rig.
func getRefineryManager(rigName string) (*refinery.Manager, *rig.Rig, error) {
	_, r, err := getRig(rigName)
	if err != nil {
		return nil, nil, err
	}

	mgr := refinery.NewManager(r)
	return mgr, r, nil
}

func runRefineryStart(cmd *cobra.Command, args []string) error {
	rigName := args[0]

	mgr, _, err := getRefineryManager(rigName)
	if err != nil {
		return err
	}

	fmt.Printf("Starting refinery for %s...\n", rigName)

	if err := mgr.Start(refineryForeground); err != nil {
		if err == refinery.ErrAlreadyRunning {
			fmt.Printf("%s Refinery is already running\n", style.Dim.Render("⚠"))
			return nil
		}
		return fmt.Errorf("starting refinery: %w", err)
	}

	if refineryForeground {
		// This will block until stopped
		return nil
	}

	fmt.Printf("%s Refinery started for %s\n", style.Bold.Render("✓"), rigName)
	fmt.Printf("  %s\n", style.Dim.Render("Use 'gt refinery status' to check progress"))
	return nil
}

func runRefineryStop(cmd *cobra.Command, args []string) error {
	rigName := args[0]

	mgr, _, err := getRefineryManager(rigName)
	if err != nil {
		return err
	}

	if err := mgr.Stop(); err != nil {
		if err == refinery.ErrNotRunning {
			fmt.Printf("%s Refinery is not running\n", style.Dim.Render("⚠"))
			return nil
		}
		return fmt.Errorf("stopping refinery: %w", err)
	}

	fmt.Printf("%s Refinery stopped for %s\n", style.Bold.Render("✓"), rigName)
	return nil
}

func runRefineryStatus(cmd *cobra.Command, args []string) error {
	rigName := args[0]

	mgr, _, err := getRefineryManager(rigName)
	if err != nil {
		return err
	}

	ref, err := mgr.Status()
	if err != nil {
		return fmt.Errorf("getting status: %w", err)
	}

	// JSON output
	if refineryStatusJSON {
		enc := json.NewEncoder(os.Stdout)
		enc.SetIndent("", "  ")
		return enc.Encode(ref)
	}

	// Human-readable output
	fmt.Printf("%s Refinery: %s\n\n", style.Bold.Render("⚙"), rigName)

	stateStr := string(ref.State)
	switch ref.State {
	case refinery.StateRunning:
		stateStr = style.Bold.Render("● running")
	case refinery.StateStopped:
		stateStr = style.Dim.Render("○ stopped")
	case refinery.StatePaused:
		stateStr = style.Dim.Render("⏸ paused")
	}
	fmt.Printf("  State: %s\n", stateStr)

	if ref.StartedAt != nil {
		fmt.Printf("  Started: %s\n", ref.StartedAt.Format("2006-01-02 15:04:05"))
	}

	if ref.CurrentMR != nil {
		fmt.Printf("\n  %s\n", style.Bold.Render("Currently Processing:"))
		fmt.Printf("    Branch: %s\n", ref.CurrentMR.Branch)
		fmt.Printf("    Worker: %s\n", ref.CurrentMR.Worker)
		if ref.CurrentMR.IssueID != "" {
			fmt.Printf("    Issue:  %s\n", ref.CurrentMR.IssueID)
		}
	}

	// Get queue length
	queue, _ := mgr.Queue()
	pendingCount := 0
	for _, item := range queue {
		if item.Position > 0 { // Not currently processing
			pendingCount++
		}
	}
	fmt.Printf("\n  Queue: %d pending\n", pendingCount)

	if ref.LastMergeAt != nil {
		fmt.Printf("  Last merge: %s\n", ref.LastMergeAt.Format("2006-01-02 15:04:05"))
	}

	fmt.Printf("\n  %s\n", style.Bold.Render("Statistics:"))
	fmt.Printf("    Merged today:  %d\n", ref.Stats.TodayMerged)
	fmt.Printf("    Failed today:  %d\n", ref.Stats.TodayFailed)
	fmt.Printf("    Total merged:  %d\n", ref.Stats.TotalMerged)
	fmt.Printf("    Total failed:  %d\n", ref.Stats.TotalFailed)

	return nil
}

func runRefineryQueue(cmd *cobra.Command, args []string) error {
	rigName := args[0]

	mgr, _, err := getRefineryManager(rigName)
	if err != nil {
		return err
	}

	queue, err := mgr.Queue()
	if err != nil {
		return fmt.Errorf("getting queue: %w", err)
	}

	// JSON output
	if refineryQueueJSON {
		enc := json.NewEncoder(os.Stdout)
		enc.SetIndent("", "  ")
		return enc.Encode(queue)
	}

	// Human-readable output
	fmt.Printf("%s Merge queue for '%s':\n\n", style.Bold.Render("📋"), rigName)

	if len(queue) == 0 {
		fmt.Printf("  %s\n", style.Dim.Render("(empty)"))
		return nil
	}

	for _, item := range queue {
		status := ""
		prefix := fmt.Sprintf("  %d.", item.Position)

		if item.Position == 0 {
			prefix = "  ▶"
			status = style.Bold.Render("[processing]")
		} else {
			switch item.MR.Status {
			case refinery.MROpen:
				if item.MR.Error != "" {
					status = style.Dim.Render("[needs-rework]")
				} else {
					status = style.Dim.Render("[pending]")
				}
			case refinery.MRInProgress:
				status = style.Bold.Render("[processing]")
			case refinery.MRClosed:
				switch item.MR.CloseReason {
				case refinery.CloseReasonMerged:
					status = style.Bold.Render("[merged]")
				case refinery.CloseReasonRejected:
					status = style.Dim.Render("[rejected]")
				case refinery.CloseReasonConflict:
					status = style.Dim.Render("[conflict]")
				case refinery.CloseReasonSuperseded:
					status = style.Dim.Render("[superseded]")
				default:
					status = style.Dim.Render("[closed]")
				}
			}
		}

		issueInfo := ""
		if item.MR.IssueID != "" {
			issueInfo = fmt.Sprintf(" (%s)", item.MR.IssueID)
		}

		fmt.Printf("%s %s %s/%s%s %s\n",
			prefix,
			status,
			item.MR.Worker,
			item.MR.Branch,
			issueInfo,
			style.Dim.Render(item.Age))
	}

	return nil
}

func runRefineryAttach(cmd *cobra.Command, args []string) error {
	rigName := args[0]

	townRoot, err := workspace.FindFromCwdOrError()
	if err != nil {
		return fmt.Errorf("not in a Gas Town workspace: %w", err)
	}

	// Session name follows the same pattern as refinery manager
	sessionID := fmt.Sprintf("gt-%s-refinery", rigName)

	// Check if session exists
	t := tmux.NewTmux()
	running, err := t.HasSession(sessionID)
	if err != nil {
		return fmt.Errorf("checking session: %w", err)
	}
	if !running {
		return fmt.Errorf("refinery is not running for rig '%s'", rigName)
	}

	// Verify rig exists
	rigsConfigPath := filepath.Join(townRoot, "mayor", "rigs.json")
	rigsConfig, err := config.LoadRigsConfig(rigsConfigPath)
	if err != nil {
		rigsConfig = &config.RigsConfig{Rigs: make(map[string]config.RigEntry)}
	}

	g := git.NewGit(townRoot)
	rigMgr := rig.NewManager(townRoot, rigsConfig, g)
	if _, err := rigMgr.GetRig(rigName); err != nil {
		return fmt.Errorf("rig '%s' not found", rigName)
	}

	// Attach to the session
	return t.AttachSession(sessionID)
}