package classify

import (
	"encoding/json"
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
)

// Migration 单个迁移项
type Migration struct {
	Source string `json:"source"`
	Target string `json:"target"`
}

// MigrationPlan 迁移计划
type MigrationPlan struct {
	Total      int         `json:"total"`
	Migrations []Migration `json:"migrations"`
}

// LoadClassification 加载分类结果
func LoadClassification(vaultPath, filename string) (*ClassificationResult, error) {
	path := filepath.Join(vaultPath, filename)
	data, err := os.ReadFile(path)
	if err != nil {
		return nil, fmt.Errorf("读取文件失败: %w", err)
	}

	var result ClassificationResult
	if err := json.Unmarshal(data, &result); err != nil {
		return nil, fmt.Errorf("解析 JSON 失败: %w", err)
	}

	return &result, nil
}

// GenerateMigrationPlan 生成迁移计划
func GenerateMigrationPlan(vaultPath string, classification *ClassificationResult) (*MigrationPlan, error) {
	plan := &MigrationPlan{
		Total:      len(classification.Items),
		Migrations: []Migration{},
	}

	// 跟踪已使用的目标路径
	usedTargets := make(map[string]bool)

	for _, item := range classification.Items {
		// 根据 platform 和 device 生成目标路径
		targetDir := getTargetDir(item.Platform, item.Device)
		baseName := filepath.Base(item.Path)
		targetPath := filepath.Join(targetDir, baseName)

		// 如果目标路径已使用，添加数字后缀直到找到唯一路径
		counter := 1
		for usedTargets[targetPath] {
			counter++
			ext := filepath.Ext(baseName)
			nameWithoutExt := strings.TrimSuffix(baseName, ext)
			targetPath = filepath.Join(targetDir, fmt.Sprintf("%s_%d%s", nameWithoutExt, counter, ext))
		}
		usedTargets[targetPath] = true

		plan.Migrations = append(plan.Migrations, Migration{
			Source: item.Path,
			Target: targetPath,
		})
	}

	return plan, nil
}

// getTargetDir 根据平台和设备获取目标目录
func getTargetDir(platform, device string) string {
	// 平台目录映射（支持中文和英文标识符）
	platformDir := map[string]string{
		// 英文标识符
		"elc":         "电子秤平台",
		"ops":         "运营管理平台",
		"both":        "共有硬件",
		"third_party": "第三方平台",
		"general":     "通用",
		// 中文标识符
		"电子秤平台":   "电子秤平台",
		"运营管理平台": "运营管理平台",
		"共有":         "共有硬件",
		"第三方平台":   "第三方平台",
		"通用":         "通用",
	}

	// 设备目录映射（支持中文和英文标识符）
	deviceDir := map[string]string{
		// 英文标识符
		"scale":         "电子秤",
		"gun":           "智能枪",
		"valve":         "智能阀",
		"box":           "艾信盒子",
		"app_safety":    "安全用气App",
		"app_delivery":  "易配送App",
		"app_assistant": "艾信助手App",
		"app_lpg":       "艾信LPG小程序",
		"app_shipping":  "艾信发货小程序",
		"none":          "通用",
		// 中文标识符
		"电子秤":          "电子秤",
		"智能枪":          "智能枪",
		"智能阀":          "智能阀",
		"艾信盒子":        "艾信盒子",
		"安全用气App":     "安全用气App",
		"易配送App":       "易配送App",
		"艾信助手App":     "艾信助手App",
		"艾信LPG小程序":   "艾信LPG小程序",
		"艾信发货小程序":  "艾信发货小程序",
		"无":              "通用",
		"综合":            "通用",
	}

	pDir := platformDir[platform]
	if pDir == "" {
		pDir = "通用"
	}

	dDir := deviceDir[device]
	if dDir == "" {
		dDir = "通用"
	}

	return filepath.Join(pDir, dDir)
}

// SaveMigrationPlan 保存迁移计划
func SaveMigrationPlan(vaultPath string, plan *MigrationPlan) error {
	path := filepath.Join(vaultPath, "migration-plan.json")
	data, err := json.MarshalIndent(plan, "", "  ")
	if err != nil {
		return err
	}

	return os.WriteFile(path, data, 0644)
}

// ExecuteMigration 执行迁移
func ExecuteMigration(vaultPath string, plan *MigrationPlan) error {
	for i, migration := range plan.Migrations {
		fmt.Printf("[%d/%d] 移动 %s -> %s\n", i+1, len(plan.Migrations), migration.Source, migration.Target)

		sourcePath := filepath.Join(vaultPath, migration.Source)
		targetPath := filepath.Join(vaultPath, migration.Target)

		// 检查源文件是否存在
		if _, err := os.Stat(sourcePath); os.IsNotExist(err) {
			fmt.Printf("  跳过（源文件不存在）\n")
			continue
		}

		// 创建目标目录
		targetDir := filepath.Dir(targetPath)
		if err := os.MkdirAll(targetDir, 0755); err != nil {
			return fmt.Errorf("创建目录失败: %w", err)
		}

		// 使用 git mv 保留历史
		cmd := exec.Command("git", "mv", sourcePath, targetPath)
		cmd.Dir = vaultPath
		if output, err := cmd.CombinedOutput(); err != nil {
			return fmt.Errorf("git mv 失败: %w\n%s", err, output)
		}
	}

	return nil
}