package database

import (
	"log/slog"

	"silk-server-go/internal/config"
	"silk-server-go/internal/model"

	"gorm.io/driver/postgres"
	"gorm.io/gorm"
	"gorm.io/gorm/logger"
)

var DB *gorm.DB

func Init(cfg *config.Config) error {
	db, err := gorm.Open(postgres.Open(cfg.PG), &gorm.Config{
		Logger: logger.Default.LogMode(logger.Warn),
	})
	if err != nil {
		return err
	}
	DB = db
	// 自动迁移（错误不阻止启动，仅记录警告）
	if err := db.AutoMigrate(
		&model.User{}, &model.Room{}, &model.Device{}, &model.Sensor{},
		&model.Threshold{}, &model.Alarm{}, &model.Camera{}, &model.VideoClip{},
		&model.AuditLog{}, &model.Telemetry{},
		&model.Permission{}, &model.RolePermission{},
	); err != nil {
		slog.Warn("自动迁移有警告（可忽略）", "err", err)
	}
	// 初始化权限种子数据
	seedPermissions(db)
	slog.Info("数据库连接成功，自动迁移完成")
	return nil
}

// seedPermissions 初始化权限和角色-权限映射种子数据（幂等）
func seedPermissions(db *gorm.DB) {
	// 1. 写入权限定义（已存在则跳过）
	codeToID := make(map[string]string)
	for _, p := range model.AllPermissions {
		var existing model.Permission
		if db.Where("code = ?", p.Code).First(&existing).Error == nil {
			codeToID[p.Code] = existing.ID
			continue
		}
		desc := p.Description
		perm := model.Permission{
			Code:        p.Code,
			Name:        p.Name,
			Description: &desc,
		}
		if err := db.Create(&perm).Error; err != nil {
			slog.Warn("写入权限种子失败", "code", p.Code, "err", err)
			continue
		}
		codeToID[p.Code] = perm.ID
	}

	// 2. 写入角色-权限映射（已存在则跳过）
	for role, codes := range model.RolePermissionMap {
		for _, code := range codes {
			pid, ok := codeToID[code]
			if !ok {
				continue
			}
			var cnt int64
			db.Model(&model.RolePermission{}).
				Where("role = ? AND permission_id = ?", role, pid).
				Count(&cnt)
			if cnt > 0 {
				continue
			}
			db.Create(&model.RolePermission{Role: role, PermissionID: pid})
		}
	}
}