package dao

import (
	"database/sql"
	"fmt"

	"dd_fiber_api/internal/document"
	"dd_fiber_api/pkg/database"

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

// FileDAO 文档文件数据访问
type FileDAO struct {
	client *database.MySQLClient
}

// NewFileDAO 创建 FileDAO
func NewFileDAO(client *database.MySQLClient) *FileDAO {
	return &FileDAO{client: client}
}

// Create 创建文档记录
func (d *FileDAO) Create(f *document.DocFile) error {
	if d.client == nil {
		return fmt.Errorf("mysql client is nil")
	}
	table := "doc_files"
	data := []map[string]any{
		{
			"id":         f.ID,
			"folder_id":  f.FolderID,
			"name":       f.Name,
			"file_name":  f.FileName,
			"file_url":   f.FileURL,
			"file_size":  f.FileSize,
			"mime_type":  f.MimeType,
		},
	}
	cond, vals, err := builder.BuildInsert(table, data)
	if err != nil {
		return err
	}
	_, err = d.client.DB.Exec(cond, vals...)
	return err
}

// GetByID 根据 ID 获取
func (d *FileDAO) GetByID(id string) (*document.DocFile, error) {
	if d.client == nil {
		return nil, fmt.Errorf("mysql client is nil")
	}
	table := "doc_files"
	where := map[string]any{"id": id}
	cond, vals, err := builder.BuildSelect(table, where, []string{"id", "folder_id", "name", "file_name", "file_url", "file_size", "mime_type", "created_at", "updated_at"})
	if err != nil {
		return nil, err
	}
	var f document.DocFile
	var createdAt, updatedAt sql.NullString
	err = d.client.DB.QueryRow(cond, vals...).Scan(&f.ID, &f.FolderID, &f.Name, &f.FileName, &f.FileURL, &f.FileSize, &f.MimeType, &createdAt, &updatedAt)
	if err == sql.ErrNoRows {
		return nil, nil
	}
	if err != nil {
		return nil, err
	}
	if createdAt.Valid {
		f.CreatedAt = createdAt.String
	}
	if updatedAt.Valid {
		f.UpdatedAt = updatedAt.String
	}
	return &f, nil
}

// Update 更新（仅名称等可改）
func (d *FileDAO) Update(f *document.DocFile) error {
	if d.client == nil {
		return fmt.Errorf("mysql client is nil")
	}
	table := "doc_files"
	where := map[string]any{"id": f.ID}
	data := map[string]any{"name": f.Name}
	cond, vals, err := builder.BuildUpdate(table, where, data)
	if err != nil {
		return err
	}
	_, err = d.client.DB.Exec(cond, vals...)
	return err
}

// Delete 删除
func (d *FileDAO) Delete(id string) error {
	if d.client == nil {
		return fmt.Errorf("mysql client is nil")
	}
	table := "doc_files"
	where := map[string]any{"id": id}
	cond, vals, err := builder.BuildDelete(table, where)
	if err != nil {
		return err
	}
	_, err = d.client.DB.Exec(cond, vals...)
	return err
}

// ListByFolderID 按文件夹 ID 列出文件
func (d *FileDAO) ListByFolderID(folderID string) ([]*document.DocFile, error) {
	if d.client == nil {
		return nil, fmt.Errorf("mysql client is nil")
	}
	table := "doc_files"
	where := map[string]any{"folder_id": folderID}
	cond, vals, err := builder.BuildSelect(table, where, []string{"id", "folder_id", "name", "file_name", "file_url", "file_size", "mime_type", "created_at", "updated_at"})
	if err != nil {
		return nil, err
	}
	cond += " ORDER BY created_at DESC"
	rows, err := d.client.DB.Query(cond, vals...)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	var list []*document.DocFile
	for rows.Next() {
		var f document.DocFile
		var createdAt, updatedAt sql.NullString
		if err := rows.Scan(&f.ID, &f.FolderID, &f.Name, &f.FileName, &f.FileURL, &f.FileSize, &f.MimeType, &createdAt, &updatedAt); err != nil {
			continue
		}
		if createdAt.Valid {
			f.CreatedAt = createdAt.String
		}
		if updatedAt.Valid {
			f.UpdatedAt = updatedAt.String
		}
		list = append(list, &f)
	}
	return list, rows.Err()
}

// DeleteByFolderID 删除该文件夹下所有文件记录
func (d *FileDAO) DeleteByFolderID(folderID string) error {
	if d.client == nil {
		return fmt.Errorf("mysql client is nil")
	}
	_, err := d.client.DB.Exec("DELETE FROM doc_files WHERE folder_id = ?", folderID)
	return err
}