package dao

import (
	"database/sql"
	"fmt"

	"dd_fiber_api/internal/admin_auth"
	"dd_fiber_api/pkg/database"

	"github.com/didi/gendry/builder"
)

// PermissionDAO 权限数据访问对象
type PermissionDAO struct {
	client *database.MySQLClient
}

// NewPermissionDAO 创建权限DAO
func NewPermissionDAO(client *database.MySQLClient) *PermissionDAO {
	return &PermissionDAO{
		client: client,
	}
}

// List 列出权限（支持分页和搜索）
func (d *PermissionDAO) List(keyword, resource string, page, pageSize int) ([]*admin_auth.AdminPermission, int, error) {
	table := "admin_permissions"

	// 构建查询条件
	where := map[string]any{}
	if keyword != "" {
		where["_or"] = []map[string]any{
			{"name like": "%" + keyword + "%"},
			{"code like": "%" + keyword + "%"},
			{"description like": "%" + keyword + "%"},
		}
	}
	if resource != "" {
		where["resource"] = resource
	}

	// 查询总数
	countFields := []string{"COUNT(*) as total"}
	countCond, countVals, err := builder.BuildSelect(table, where, countFields)
	if err != nil {
		return nil, 0, fmt.Errorf("构建统计查询失败: %v", err)
	}

	var total int
	err = d.client.DB.QueryRow(countCond, countVals...).Scan(&total)
	if err != nil {
		return nil, 0, fmt.Errorf("查询权限总数失败: %v", err)
	}

	// 查询数据
	selectFields := []string{"id", "name", "code", "resource", "action", "description", "created_at", "updated_at"}
	cond, vals, err := builder.BuildSelect(table, where, selectFields)
	if err != nil {
		return nil, 0, fmt.Errorf("构建查询失败: %v", err)
	}

	// 添加排序和分页
	offset := (page - 1) * pageSize
	cond += " ORDER BY resource, action ASC LIMIT ? OFFSET ?"
	vals = append(vals, pageSize, offset)

	rows, err := d.client.DB.Query(cond, vals...)
	if err != nil {
		return nil, 0, fmt.Errorf("查询权限列表失败: %v", err)
	}
	defer rows.Close()

	var permissions []*admin_auth.AdminPermission
	for rows.Next() {
		var permission admin_auth.AdminPermission
		var description sql.NullString

		err := rows.Scan(
			&permission.ID,
			&permission.Name,
			&permission.Code,
			&permission.Resource,
			&permission.Action,
			&description,
			&permission.CreatedAt,
			&permission.UpdatedAt,
		)
		if err != nil {
			continue
		}

		if description.Valid {
			permission.Description = description.String
		}

		permissions = append(permissions, &permission)
	}

	return permissions, total, nil
}

// GetByID 根据ID获取权限
func (d *PermissionDAO) GetByID(id string) (*admin_auth.AdminPermission, error) {
	query := `SELECT id, name, code, resource, action, description, created_at, updated_at 
	          FROM admin_permissions WHERE id = ?`

	var permission admin_auth.AdminPermission
	var description sql.NullString

	err := d.client.DB.QueryRow(query, id).Scan(
		&permission.ID,
		&permission.Name,
		&permission.Code,
		&permission.Resource,
		&permission.Action,
		&description,
		&permission.CreatedAt,
		&permission.UpdatedAt,
	)

	if err == sql.ErrNoRows {
		return nil, nil
	}
	if err != nil {
		return nil, fmt.Errorf("查询权限失败: %v", err)
	}

	if description.Valid {
		permission.Description = description.String
	}

	return &permission, nil
}

// GetByCode 根据代码获取权限
func (d *PermissionDAO) GetByCode(code string) (*admin_auth.AdminPermission, error) {
	query := `SELECT id, name, code, resource, action, description, created_at, updated_at 
	          FROM admin_permissions WHERE code = ?`

	var permission admin_auth.AdminPermission
	var description sql.NullString

	err := d.client.DB.QueryRow(query, code).Scan(
		&permission.ID,
		&permission.Name,
		&permission.Code,
		&permission.Resource,
		&permission.Action,
		&description,
		&permission.CreatedAt,
		&permission.UpdatedAt,
	)

	if err == sql.ErrNoRows {
		return nil, nil
	}
	if err != nil {
		return nil, fmt.Errorf("查询权限失败: %v", err)
	}

	if description.Valid {
		permission.Description = description.String
	}

	return &permission, nil
}

// Create 创建权限
func (d *PermissionDAO) Create(permission *admin_auth.AdminPermission) error {
	table := "admin_permissions"
	data := []map[string]any{
		{
			"id":          permission.ID,
			"name":        permission.Name,
			"code":        permission.Code,
			"resource":    permission.Resource,
			"action":      permission.Action,
			"description": permission.Description,
		},
	}

	cond, vals, err := builder.BuildInsert(table, data)
	if err != nil {
		return fmt.Errorf("构建插入语句失败: %v", err)
	}

	_, err = d.client.DB.Exec(cond, vals...)
	if err != nil {
		return fmt.Errorf("创建权限失败: %v", err)
	}

	return nil
}

// Update 更新权限
func (d *PermissionDAO) Update(permission *admin_auth.AdminPermission) error {
	table := "admin_permissions"
	where := map[string]any{
		"id": permission.ID,
	}

	data := map[string]any{
		"name":        permission.Name,
		"code":        permission.Code,
		"resource":    permission.Resource,
		"action":      permission.Action,
		"description": permission.Description,
	}

	cond, vals, err := builder.BuildUpdate(table, where, data)
	if err != nil {
		return fmt.Errorf("构建更新语句失败: %v", err)
	}

	_, err = d.client.DB.Exec(cond, vals...)
	if err != nil {
		return fmt.Errorf("更新权限失败: %v", err)
	}

	return nil
}

// Delete 删除权限
func (d *PermissionDAO) Delete(id string) error {
	// 先删除角色权限关联
	deleteRolePermQuery := `DELETE FROM admin_role_permissions WHERE permission_id = ?`
	_, err := d.client.DB.Exec(deleteRolePermQuery, id)
	if err != nil {
		return fmt.Errorf("删除角色权限关联失败: %v", err)
	}

	// 删除权限
	deleteQuery := `DELETE FROM admin_permissions WHERE id = ?`
	_, err = d.client.DB.Exec(deleteQuery, id)
	if err != nil {
		return fmt.Errorf("删除权限失败: %v", err)
	}

	return nil
}

// GetResources 获取所有资源列表
func (d *PermissionDAO) GetResources() ([]string, error) {
	query := `SELECT DISTINCT resource FROM admin_permissions ORDER BY resource`

	rows, err := d.client.DB.Query(query)
	if err != nil {
		return nil, fmt.Errorf("查询资源列表失败: %v", err)
	}
	defer rows.Close()

	var resources []string
	for rows.Next() {
		var resource string
		if err := rows.Scan(&resource); err != nil {
			continue
		}
		resources = append(resources, resource)
	}

	return resources, nil
}