package cmd

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

	"github.com/aisim/kb-cli/internal/index"
	"github.com/spf13/cobra"
)

var indexCmd = &cobra.Command{
	Use:   "index",
	Short: "索引管理",
}

var indexBuildCmd = &cobra.Command{
	Use:   "build",
	Short: "构建或重建知识库索引",
	RunE:  runIndexBuild,
}

var indexStatusCmd = &cobra.Command{
	Use:   "status",
	Short: "查看索引状态信息",
	RunE:  runIndexStatus,
}

var indexGcCmd = &cobra.Command{
	Use:   "gc",
	Short: "清理孤立节点和边",
	RunE:  runIndexGc,
}

func init() {
	rootCmd.AddCommand(indexCmd)
	indexCmd.AddCommand(indexBuildCmd)
	indexCmd.AddCommand(indexStatusCmd)
	indexCmd.AddCommand(indexGcCmd)
}

func runIndexBuild(cmd *cobra.Command, args []string) error {
	// 打开索引
	store, err := index.Open(dbPath)
	if err != nil {
		return fmt.Errorf("打开索引失败: %w", err)
	}
	defer store.Close()

	// 获取当前 commit
	commit, err := index.GetGitCommit(vaultPath)
	if err != nil {
		fmt.Fprintln(os.Stderr, "警告: 无法获取 git commit:", err)
		commit = ""
	}

	fmt.Fprintln(os.Stderr, "正在重建索引...")
	if err := rebuildIndex(store, commit); err != nil {
		return fmt.Errorf("重建索引失败: %w", err)
	}

	fmt.Fprintln(os.Stderr, "索引重建完成")
	return nil
}

func runIndexStatus(cmd *cobra.Command, args []string) error {
	// 打开索引
	store, err := index.Open(dbPath)
	if err != nil {
		return fmt.Errorf("打开索引失败: %w", err)
	}
	defer store.Close()

	// 获取元信息
	gitCommit, err := store.GetMeta("git_commit")
	if err != nil {
		return fmt.Errorf("获取元信息失败: %w", err)
	}
	builtAt, _ := store.GetMeta("built_at")

	// 获取节点数
	nodeCount, err := store.NodeCount()
	if err != nil {
		return fmt.Errorf("获取节点数失败: %w", err)
	}

	// 获取边数
	edgeCount, err := store.EdgeCount()
	if err != nil {
		return fmt.Errorf("获取边数失败: %w", err)
	}

	// 获取当前 commit
	currentCommit, err := index.GetGitCommit(vaultPath)
	if err != nil {
		currentCommit = ""
	}

	// 输出状态
	fmt.Printf("索引状态:\n")
	fmt.Printf("  知识库路径: %s\n", vaultPath)
	fmt.Printf("  索引文件: %s\n", dbPath)
	fmt.Printf("  节点数: %d\n", nodeCount)
	fmt.Printf("  边数: %d\n", edgeCount)
	fmt.Printf("  索引 commit: %s\n", gitCommit)
	fmt.Printf("  当前 commit: %s\n", currentCommit)
	fmt.Printf("  构建时间: %s\n", builtAt)

	// 检查是否需要更新
	needsRebuild, _, err := index.NeedsRebuild(store, vaultPath)
	if err != nil {
		return fmt.Errorf("检查索引状态失败: %w", err)
	}

	if needsRebuild {
		fmt.Printf("  状态: 需要更新\n")
	} else {
		fmt.Printf("  状态: 最新\n")
	}

	return nil
}

func runIndexGc(cmd *cobra.Command, args []string) error {
	// 展开 ~ 为实际路径
	expandedVaultPath := vaultPath
	if strings.HasPrefix(vaultPath, "~/") {
		home, err := os.UserHomeDir()
		if err != nil {
			return fmt.Errorf("获取用户目录失败: %w", err)
		}
		expandedVaultPath = filepath.Join(home, vaultPath[2:])
	}

	// 打开索引
	store, err := index.Open(dbPath)
	if err != nil {
		return fmt.Errorf("打开索引失败: %w", err)
	}
	defer store.Close()

	fmt.Fprintln(os.Stderr, "正在清理孤立节点和边...")

	// 获取所有节点路径
	nodes, err := store.GetAllNodes()
	if err != nil {
		return fmt.Errorf("获取节点失败: %w", err)
	}

	// 检查文件是否存在
	var orphanPaths []string
	for _, node := range nodes {
		fullPath := filepath.Join(expandedVaultPath, node.Path)
		if _, err := os.Stat(fullPath); os.IsNotExist(err) {
			orphanPaths = append(orphanPaths, node.Path)
		}
	}

	if len(orphanPaths) == 0 {
		fmt.Fprintln(os.Stderr, "没有发现孤立节点")
		return nil
	}

	fmt.Fprintf(os.Stderr, "发现 %d 个孤立节点，正在清理...\n", len(orphanPaths))

	// 删除孤立节点
	deletedCount, err := store.DeleteNodesByPaths(orphanPaths)
	if err != nil {
		return fmt.Errorf("删除节点失败: %w", err)
	}

	fmt.Fprintf(os.Stderr, "已清理 %d 个孤立节点\n", deletedCount)
	return nil
}