import { existsSync, readFileSync } from 'node:fs';
import path from 'node:path';
import { LEGACY_COLUMNS, type LegacyTable } from './columns';
import { readTable, toObjects, type SqlValue } from './parser';

/**
 * 旧库 dump 的默认位置。
 * 兼顾两种运行方式：`pnpm legacy:check`（cwd 为包根）与 vitest（cwd 为包根）。
 * 可用 LEGACY_DUMP 环境变量覆盖。
 */
function resolveDefaultDumpPath(): string {
  const candidates = [
    path.resolve(process.cwd(), '../数据库/api_yeomai_site_mysql.sql'),
    path.resolve(process.cwd(), '数据库/api_yeomai_site_mysql.sql'),
  ];
  return candidates.find((p) => existsSync(p)) ?? candidates[0]!;
}

export const DEFAULT_DUMP_PATH = process.env.LEGACY_DUMP ?? resolveDefaultDumpPath();

export type LegacyRows = Record<LegacyTable, Record<string, SqlValue>[]>;

export function loadLegacyDump(dumpPath: string = process.env.LEGACY_DUMP ?? DEFAULT_DUMP_PATH): LegacyRows {
  const sql = readFileSync(dumpPath, 'utf8');
  const result = {} as LegacyRows;
  for (const table of Object.keys(LEGACY_COLUMNS) as LegacyTable[]) {
    result[table] = toObjects(readTable(sql, table), [...LEGACY_COLUMNS[table]]);
  }
  return result;
}

export function asString(v: SqlValue): string {
  return v === null ? '' : String(v);
}