package database

import (
	"fmt"
	"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
	if err := RunMigrations(db); err != nil {
		return err
	}
	if err := CheckSchemaVersion(db, CurrentSchemaVersion); err != nil {
		return err
	}
	if cfg.AllowDevAutoMigrate && cfg.AppEnv != "production" {
		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{},
			&model.Disease{}, &model.KnowledgeArticle{},
			&model.InspectionRecord{},
			&model.OutboxEvent{},
			&model.Notification{},
			&model.DetectionTask{},
			&model.Sample{},
			&model.DiseaseEvent{},
			&model.Tray{}, &model.Batch{}, &model.RearingRecord{},
			&model.WechatBinding{},
			&model.WeatherAlert{},
			&model.LampTest{}, &model.LampTestStep{},
			&model.Consumable{},
			&model.Consultation{},
			&model.SpectrumEntry{},
			&model.TraceRecord{},
		); err != nil {
			return fmt.Errorf("开发环境 AutoMigrate 失败: %w", err)
		}
		slog.Warn("开发环境 AutoMigrate 已启用，SQL 迁移仍是生产 schema 事实来源")
	}
	// 初始化权限种子数据
	seedPermissions(db)
	// 初始化知识库种子数据
	seedKnowledge(db)
	slog.Info("数据库连接成功，版本化迁移完成", "schemaVersion", CurrentSchemaVersion)
	return nil
}

// seedKnowledge 初始化知识库种子数据（幂等：按名称/类型+标题判重）
func seedKnowledge(db *gorm.DB) {
	for _, d := range model.SeedDiseases {
		var cnt int64
		db.Model(&model.Disease{}).Where("name = ?", d.Name).Count(&cnt)
		if cnt == 0 {
			if err := db.Create(&d).Error; err != nil {
				slog.Warn("写入病种种子失败", "name", d.Name, "err", err)
			}
		}
	}
	for _, a := range model.SeedKnowledgeArticles {
		var cnt int64
		db.Model(&model.KnowledgeArticle{}).Where("kind = ? AND title = ?", a.Kind, a.Title).Count(&cnt)
		if cnt == 0 {
			if err := db.Create(&a).Error; err != nil {
				slog.Warn("写入知识文章种子失败", "title", a.Title, "err", err)
			}
		}
	}
}

// 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})
		}
	}
}