import assert from "node:assert/strict";
import fs     from "node:fs";
import path   from "node:path";
import url    from "node:url";

import sqlite from "./sqlite.cjs";

import * as u from "./utils.mjs";


const DIRNAME = path.dirname(url.fileURLToPath(import.meta.url));
export const MIGRATIONS_DIR = DIRNAME + "/sql/migrations/";

export const runMigrations = async (logFn, db) => {
	assert(db);

	await db.exec(`
		BEGIN TRANSACTION;
		CREATE TABLE IF NOT EXISTS migrations (
			filename TEXT NOT NULL PRIMARY KEY
		);
		COMMIT TRANSACTION;
	`);

	const done = [...(await db.all("SELECT filename FROM migrations;"))]
		.map(row => row.filename);
	const allFiles = fs.readdirSync(MIGRATIONS_DIR, "UTF-8");
	const pending = u.difference(new Set(allFiles), new Set(done));
	const sortedPending = [...pending].sort(u.strSortFn);

	for (const filename of sortedPending) {
		logFn({ log: "exec-migration", filename });
		const sql = fs.readFileSync(MIGRATIONS_DIR + filename, "UTF-8");
		await db.exec("BEGIN TRANSACTION;");
		await db.exec(sql);
		await db.run(
			"INSERT INTO migrations (filename) VALUES ($filename);",
			{ $filename: filename },
		);
		await db.exec("COMMIT TRANSACTION;")
	}
};