package cmd

import (
	"encoding/json"
	"fmt"
	"os"
	"strings"

	"github.com/spf13/cobra"
)

var infoCmd = &cobra.Command{
	Use:     "info",
	GroupID: GroupDiag,
	Short:   "Show Gas Town information and what's new",
	Long: `Display information about the current Gas Town installation.

This command shows:
  - Version information
  - What's new in recent versions (with --whats-new flag)

Examples:
  gt info
  gt info --whats-new
  gt info --whats-new --json`,
	Run: func(cmd *cobra.Command, args []string) {
		whatsNewFlag, _ := cmd.Flags().GetBool("whats-new")
		jsonFlag, _ := cmd.Flags().GetBool("json")

		if whatsNewFlag {
			showWhatsNew(jsonFlag)
			return
		}

		// Default: show basic info
		info := map[string]interface{}{
			"version": Version,
			"build":   Build,
		}

		if commit := resolveCommitHash(); commit != "" {
			info["commit"] = shortCommit(commit)
		}
		if branch := resolveBranch(); branch != "" {
			info["branch"] = branch
		}

		if jsonFlag {
			enc := json.NewEncoder(os.Stdout)
			enc.SetIndent("", "  ")
			_ = enc.Encode(info)
			return
		}

		fmt.Printf("Gas Town v%s (%s)\n", Version, Build)
		if commit, ok := info["commit"].(string); ok {
			if branch, ok := info["branch"].(string); ok {
				fmt.Printf("  %s@%s\n", branch, commit)
			} else {
				fmt.Printf("  %s\n", commit)
			}
		}
		fmt.Println("\nUse 'gt info --whats-new' to see recent changes")
	},
}

// VersionChange represents agent-relevant changes for a specific version
type VersionChange struct {
	Version string   `json:"version"`
	Date    string   `json:"date"`
	Changes []string `json:"changes"`
}

// versionChanges contains agent-actionable changes for recent versions
var versionChanges = []VersionChange{
	{
		Version: "0.2.0",
		Date:    "2026-01-04",
		Changes: []string{
			"NEW: Convoy Dashboard - Web UI for monitoring Gas Town (gt dashboard)",
			"NEW: Two-level beads architecture - hq-* prefix for town, rig prefixes for projects",
			"NEW: Multi-agent support with pluggable registry",
			"NEW: gt rig start/stop/restart/status - Multi-rig management commands",
			"NEW: Ephemeral polecat model - Immediate recycling after each work unit",
			"NEW: gt costs command - Session cost tracking and reporting",
			"NEW: Conflict resolution workflow for polecats with merge-slot gates",
			"NEW: gt convoy --tree and gt convoy check for cross-rig coordination",
			"NEW: Batch slinging - gt sling supports multiple beads at once",
			"NEW: spawn alias for start across all role subcommands",
			"NEW: gt mail archive supports multiple message IDs",
			"NEW: gt mail --all flag for clearing all mail",
			"NEW: Circuit breaker for stuck agents",
			"NEW: Binary age detection in gt status",
			"NEW: Shell completion installation instructions",
			"CHANGED: Handoff migrated to skills format",
			"CHANGED: Crew workers push directly to main (no PRs)",
			"CHANGED: Session names include town name",
			"FIX: Thread-safety for agent session resume",
			"FIX: Orphan daemon prevention via file locking",
			"FIX: Zombie tmux session cleanup",
			"FIX: Default branch detection (no longer hardcodes 'main')",
			"FIX: Enter key retry logic for reliable delivery",
			"FIX: Beads prefix routing for cross-rig operations",
		},
	},
	{
		Version: "0.1.1",
		Date:    "2026-01-02",
		Changes: []string{
			"FIX: Tmux keybindings scoped to Gas Town sessions only",
			"NEW: OSS project files - CHANGELOG.md, .golangci.yml, RELEASING.md",
			"NEW: Version bump script - scripts/bump-version.sh",
			"FIX: gt rig add and gt crew add CLI syntax documentation",
			"FIX: Rig prefix routing for agent beads",
			"FIX: Beads init targets correct database",
		},
	},
	{
		Version: "0.1.0",
		Date:    "2026-01-02",
		Changes: []string{
			"Initial public release of Gas Town",
			"NEW: Town structure - Hierarchical workspace with rigs, crews, and polecats",
			"NEW: Rig management - gt rig add/list/remove",
			"NEW: Crew workspaces - gt crew add for persistent developer workspaces",
			"NEW: Polecat workers - Transient agent workers managed by Witness",
			"NEW: Mayor - Global coordinator for cross-rig work",
			"NEW: Deacon - Town-level lifecycle patrol and heartbeat",
			"NEW: Witness - Per-rig polecat lifecycle manager",
			"NEW: Refinery - Merge queue processor with code review",
			"NEW: Convoy system - gt convoy create/list/status",
			"NEW: Sling workflow - gt sling <bead> <rig>",
			"NEW: Molecule workflows - Formula-based multi-step task execution",
			"NEW: Mail system - gt mail inbox/send/read",
			"NEW: Escalation protocol - gt escalate with severity levels",
			"NEW: Handoff mechanism - gt handoff for context-preserving session cycling",
			"NEW: Beads integration - Issue tracking via beads (bd commands)",
			"NEW: Tmux sessions with theming",
			"NEW: Status dashboard - gt status",
			"NEW: Activity feed - gt feed",
			"NEW: Nudge system - gt nudge for reliable message delivery",
		},
	},
}

// showWhatsNew displays agent-relevant changes from recent versions
func showWhatsNew(jsonOutput bool) {
	if jsonOutput {
		enc := json.NewEncoder(os.Stdout)
		enc.SetIndent("", "  ")
		_ = enc.Encode(map[string]interface{}{
			"current_version": Version,
			"recent_changes":  versionChanges,
		})
		return
	}

	// Human-readable output
	fmt.Printf("\nWhat's New in Gas Town (Current: v%s)\n", Version)
	fmt.Println(strings.Repeat("=", 50))
	fmt.Println()

	for _, vc := range versionChanges {
		// Highlight if this is the current version
		versionMarker := ""
		if vc.Version == Version {
			versionMarker = " <- current"
		}

		fmt.Printf("## v%s (%s)%s\n\n", vc.Version, vc.Date, versionMarker)

		for _, change := range vc.Changes {
			fmt.Printf("  * %s\n", change)
		}
		fmt.Println()
	}

	fmt.Println("Tip: Use 'gt info --whats-new --json' for machine-readable output")
	fmt.Println()
}

func init() {
	infoCmd.Flags().Bool("whats-new", false, "Show agent-relevant changes from recent versions")
	infoCmd.Flags().Bool("json", false, "Output in JSON format")
	rootCmd.AddCommand(infoCmd)
}