package repository

import (
	"context"
	"database/sql"
	"fmt"

	"rag/file-system/internal/domain/model"
)

type FileMetaRepoImpl struct {
	db *sql.DB
}

func NewFileMetaRepository(db *sql.DB) *FileMetaRepoImpl {
	return &FileMetaRepoImpl{db: db}
}

func (r *FileMetaRepoImpl) Create(ctx context.Context, file *model.FileMeta) error {
	_, err := r.db.ExecContext(ctx,
		`INSERT INTO files (id, folder_id, name, s3_key, s3_bucket, size, content_type, owner_id, created_at, updated_at)
		 VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10)`,
		file.ID, file.FolderID, file.Name, file.S3Key, file.S3Bucket, file.Size, file.ContentType, file.OwnerID, file.CreatedAt, file.UpdatedAt)
	if err != nil {
		return fmt.Errorf("failed to create file meta: %w", err)
	}
	return nil
}

func (r *FileMetaRepoImpl) GetByID(ctx context.Context, id string) (*model.FileMeta, error) {
	var f model.FileMeta
	err := r.db.QueryRowContext(ctx,
		`SELECT id, folder_id, name, s3_key, s3_bucket, size, content_type, owner_id, created_at, updated_at FROM files WHERE id = $1`, id).
		Scan(&f.ID, &f.FolderID, &f.Name, &f.S3Key, &f.S3Bucket, &f.Size, &f.ContentType, &f.OwnerID, &f.CreatedAt, &f.UpdatedAt)
	if err == sql.ErrNoRows {
		return nil, nil
	}
	if err != nil {
		return nil, fmt.Errorf("failed to get file meta: %w", err)
	}
	return &f, nil
}

func (r *FileMetaRepoImpl) GetByFolder(ctx context.Context, folderID string) ([]model.FileMeta, error) {
	rows, err := r.db.QueryContext(ctx,
		`SELECT id, folder_id, name, s3_key, s3_bucket, size, content_type, owner_id, created_at, updated_at FROM files WHERE folder_id = $1 ORDER BY name`, folderID)
	if err != nil {
		return nil, fmt.Errorf("failed to get files by folder: %w", err)
	}
	defer rows.Close()

	return scanFiles(rows)
}

func (r *FileMetaRepoImpl) Move(ctx context.Context, fileID string, targetFolderID string, ownerID string) error {
	result, err := r.db.ExecContext(ctx,
		`UPDATE files SET folder_id = $1, updated_at = now() WHERE id = $2 AND owner_id = $3`,
		targetFolderID, fileID, ownerID)
	if err != nil {
		return fmt.Errorf("failed to move file: %w", err)
	}
	rows, _ := result.RowsAffected()
	if rows == 0 {
		return fmt.Errorf("file not found or not owned by user")
	}
	return nil
}

func (r *FileMetaRepoImpl) Delete(ctx context.Context, id string, ownerID string) error {
	result, err := r.db.ExecContext(ctx, `DELETE FROM files WHERE id = $1 AND owner_id = $2`, id, ownerID)
	if err != nil {
		return fmt.Errorf("failed to delete file meta: %w", err)
	}
	rows, _ := result.RowsAffected()
	if rows == 0 {
		return fmt.Errorf("file not found or not owned by user")
	}
	return nil
}

func scanFiles(rows *sql.Rows) ([]model.FileMeta, error) {
	var files []model.FileMeta
	for rows.Next() {
		var f model.FileMeta
		if err := rows.Scan(&f.ID, &f.FolderID, &f.Name, &f.S3Key, &f.S3Bucket, &f.Size, &f.ContentType, &f.OwnerID, &f.CreatedAt, &f.UpdatedAt); err != nil {
			return nil, fmt.Errorf("failed to scan file: %w", err)
		}
		files = append(files, f)
	}
	return files, rows.Err()
}