/// <reference lib="esnext.asynciterable" />
// Must reference esnext.asynciterable lib, since octokit uses AsyncIterable internally
const cp = require('node:child_process');
const os = require('node:os');
const { AllPackages, getDefinitelyTyped, parseDefinitions, clean } = require('@definitelytyped/definitions-parser');
const { loggerWithErrors } = require('@definitelytyped/utils');
const { writeFile } = require('fs-extra');

async function main() {
    const options = { definitelyTypedPath: '.', progress: false, parseInParallel: true };
    const log = loggerWithErrors()[0];

    clean();
    const dt = await getDefinitelyTyped(options, log);
    await parseDefinitions(dt, { nProcesses: os.cpus().length, definitelyTypedPath: '.' }, log);
    const allPackages = await AllPackages.read(dt);
    const typings = allPackages.allTypings();
    const maxPathLen = Math.max(...typings.map(t => t.subDirectoryPath.length));
    const entries = mapDefined(typings, t => getEntry(t, maxPathLen));
    await writeFile(
        [options.definitelyTypedPath, '.github', 'CODEOWNERS'].join('/'),
        `${header}\n\n${entries.join('\n')}\n`,
        { encoding: 'utf-8' },
    );
}

runSequence([
    ['git', ['checkout', '.']], // reset any changes
]);

main()
    .then(() => {
        runSequence([
            ['git', ['add', '.github/CODEOWNERS']], // Add CODEOWNERS
            ['git', ['pull']], // Ensure we're up-to-date
            ['git', ['commit', '-m', `"🤖 Update CODEOWNERS"`]], // Commit all changes
            ['git', ['push']], // push the branch
        ]);
        console.log(`Pushed new commit.`);
    })
    .catch(e => {
        console.error(e);
        process.exit(1);
    });

/** @param {[string, string[]][]} tasks */
function runSequence(tasks) {
    for (const task of tasks) {
        console.log(`${task[0]} ${task[1].join(' ')}`);
        const result = cp.spawnSync(task[0], task[1], { timeout: 100000, shell: true, stdio: 'inherit' });
        if (result.status !== 0)
            throw new Error(`${task[0]} ${task[1].join(' ')} failed: ${result.stderr && result.stderr.toString()}`);
    }
}

const header = `# This file is generated.
# Add yourself to the "Definitions by:" list instead.
# See https://github.com/DefinitelyTyped/DefinitelyTyped#definition-owners`;

/**
 * @param { { contributors: ReadonlyArray<{githubUsername?: string }>, subDirectoryPath: string} } pkg
 * @param {number} maxPathLen
 * @return {string | undefined}
 */
function getEntry(pkg, maxPathLen) {
    const users = mapDefined(pkg.contributors, c => c.githubUsername);
    if (!users.length) {
        return undefined;
    }

    const path = `${pkg.subDirectoryPath}/`.padEnd(maxPathLen);
    return `/types/${path} ${users.map(u => `@${u}`).join(' ')}`;
}

/**
 * @template T,U
 * @param {ReadonlyArray<T>} arr
 * @param {(t: T) => U | undefined} mapper
 * @return U[]
 */
function mapDefined(arr, mapper) {
    const out = [];
    for (const a of arr) {
        const res = mapper(a);
        if (res !== undefined) {
            out.push(res);
        }
    }
    return out;
}