package user

import (
	"context"
	"errors"
	"fmt"

	"github.com/perfect-panel/server/pkg/cache"
	"github.com/perfect-panel/server/pkg/logger"
	"github.com/redis/go-redis/v9"
	"gorm.io/gorm"
)

var (
	cacheUserIdPrefix    = "cache:user:id:"
	cacheUserEmailPrefix = "cache:user:email:"
)
var _ Model = (*customUserModel)(nil)

type (
	Model interface {
		userModel
		customUserLogicModel
	}
	userModel interface {
		Insert(ctx context.Context, data *User, tx ...*gorm.DB) error
		FindOne(ctx context.Context, id int64) (*User, error)
		Update(ctx context.Context, data *User, tx ...*gorm.DB) error
		Delete(ctx context.Context, id int64, tx ...*gorm.DB) error
		Transaction(ctx context.Context, fn func(db *gorm.DB) error) error
	}

	customUserModel struct {
		*defaultUserModel
	}
	defaultUserModel struct {
		cache.CachedConn
		table string
	}
)

func newUserModel(db *gorm.DB, c *redis.Client) *defaultUserModel {
	return &defaultUserModel{
		CachedConn: cache.NewConn(db, c),
		table:      "`user`",
	}
}

func (m *defaultUserModel) batchGetCacheKeys(users ...*User) []string {
	var keys []string
	for _, user := range users {
		keys = append(keys, user.GetCacheKeys()...)
	}
	return keys
}

func (m *defaultUserModel) getCacheKeys(data *User) []string {
	if data == nil {
		return []string{}
	}
	return data.GetCacheKeys()
}

func (m *defaultUserModel) clearUserCache(ctx context.Context, data ...*User) error {
	return m.ClearUserCache(ctx, data...)
}

func (m *defaultUserModel) FindOneByEmail(ctx context.Context, email string) (*User, error) {
	var user User
	key := fmt.Sprintf("%s%v", cacheUserEmailPrefix, email)
	err := m.QueryCtx(ctx, &user, key, func(conn *gorm.DB, v interface{}) error {
		var data AuthMethods
		if err := conn.Model(&AuthMethods{}).Where("`auth_type` = 'email' AND `auth_identifier` = ?", email).First(&data).Error; err != nil {
			return err
		}
		return conn.Model(&User{}).Unscoped().Where("`id` = ?", data.UserId).Preload("UserDevices").Preload("AuthMethods").First(v).Error
	})
	return &user, err
}

func (m *defaultUserModel) Insert(ctx context.Context, data *User, tx ...*gorm.DB) error {
	err := m.ExecCtx(ctx, func(conn *gorm.DB) error {
		if len(tx) > 0 {
			conn = tx[0]
		}
		return conn.Create(&data).Error
	}, m.getCacheKeys(data)...)
	return err
}

func (m *defaultUserModel) FindOne(ctx context.Context, id int64) (*User, error) {
	userIdKey := fmt.Sprintf("%s%v", cacheUserIdPrefix, id)
	var resp User
	err := m.QueryCtx(ctx, &resp, userIdKey, func(conn *gorm.DB, v interface{}) error {
		return conn.Model(&User{}).Unscoped().Where("`id` = ?", id).Preload("UserDevices").Preload("AuthMethods").First(&resp).Error
	})
	return &resp, err
}

func (m *defaultUserModel) Update(ctx context.Context, data *User, tx ...*gorm.DB) error {
	old, err := m.FindOne(ctx, data.Id)
	if err != nil && !errors.Is(err, gorm.ErrRecordNotFound) {
		return err
	}
	err = m.ExecCtx(ctx, func(conn *gorm.DB) error {
		if len(tx) > 0 {
			conn = tx[0]
		}
		return conn.Save(data).Error
	}, m.getCacheKeys(old)...)
	return err
}

func (m *defaultUserModel) Delete(ctx context.Context, id int64, tx ...*gorm.DB) error {
	data, err := m.FindOne(ctx, id)
	if err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil
		}
		return err
	}

	// Use batch related cache cleaning, including a cache of all relevant data
	defer func() {
		if clearErr := m.BatchClearRelatedCache(ctx, data); clearErr != nil {
			// Record cache cleaning errors, but do not block deletion operations
			logger.Errorf("failed to clear related cache for user %d: %v", id, clearErr.Error())
		}
	}()

	return m.TransactCtx(ctx, func(db *gorm.DB) error {
		if len(tx) > 0 {
			db = tx[0]
		}
		// Soft deletion of user information without any processing of other information (Determine whether to allow login/subscription based on the user's deletion status)
		if err := db.Model(&User{}).Where("`id` = ?", id).Delete(&User{}).Error; err != nil {
			return err
		}

		return nil
	})
}

func (m *defaultUserModel) Transaction(ctx context.Context, fn func(db *gorm.DB) error) error {
	return m.TransactCtx(ctx, fn)
}