const { spawnSync } = require('child_process');

const { readFileSync, writeFileSync } = require('fs');

// eslint-disable-next-line import/no-extraneous-dependencies

const { default: getReleasePlan } = require('@changesets/get-release-plan');

// eslint-disable-next-line import/no-extraneous-dependencies

const { getInfo } = require('@changesets/get-github-info');

// TODO: move this to CI linting

const verbs = new Set(['Adds', 'Changes', 'Fixes', 'Moves', 'Removes', 'Updates']);

function gitCommitsSince(tag) {

const { stdout } = spawnSync('git', ['rev-list', `^${tag}`, 'HEAD']);

return stdout

.toString('utf-8')

.split('\n')

.filter(x => x);

}

function firstGitCommitOf(path) {

const { stdout } = spawnSync('git', ['rev-list', 'HEAD', '--', path]);

return stdout

.toString('utf-8')

.split(' ', 1)

.pop()

.replace(/[^A-Za-z0-9]/g, '')

.slice(0, 40);

}

async function fetchData(tag) {

const { changesets, releases } = await getReleasePlan('.');

// find the commits since the tag

const revs = gitCommitsSince(tag);

console.error(`${revs.length} commits since ${tag}`);

if (revs.length === 0) throw new Error('No commits');

if (revs.length > 50) throw new Error('Too many commits');

// tag changesets with their commits

for (const changeset of changesets) {

const commit = firstGitCommitOf(`.changeset/${changeset.id}.md`);

if (!revs.includes(commit)) throw new Error(`Unexpected commit ${changeset.commit}`);

changeset.commit = commit;

}

// list all the contributors

const contributors = JSON.parse(readFileSync('.changeset/contributors.json').toString('utf-8'));

const first = []; // first time contributors

const commits = {};

for (const commit of revs) {

const { user, pull } = await getInfo({ repo: 'keystonejs/keystone', commit });

console.error(`commit ${commit}, user ${user}, pull #${pull}`);

commits[commit] = { commit, user, pull };

if (contributors.includes(user)) continue;

first.push({ user, pull });

contributors.push(user);

}

// join some of the changeset data with the GitHub commit information

const changes = [];

for (const changeset of changesets) {

const { releases, summary, commit } = changeset;

// TODO: move this to CI linting

const describedType = summary.split(' ')[0];

if (!verbs.has(describedType)) {

console.warn(` Verb '${describedType}' is non-standard for a changeset`);

}

// poor semver precedence

let type;

for (const release of releases) {

if (['minor', 'patch', undefined].includes(type) && release.type === 'major') type = 'major';

if (['patch', undefined].includes(type) && release.type === 'minor') type = 'minor';

if ([undefined].includes(type) && release.type === 'patch') type = 'patch';

}

if (!type) throw new Error('Unknown type');

const { user, pull } = commits[commit];

commits[commit].changeset = changeset;

// only include keystone-6 packages, then strip the namespace

const publicPackages = releases

.filter(x => x.name.startsWith('@keystone-6'))

.map(x => x.name.replace('@keystone-6/', ''));

changes.push({

packages: publicPackages,

type,

commit,

summary,

user,

pull,

});

}

// only include keystone-6 packages

const packages = releases

.filter(x => x.name.startsWith('@keystone-6'))

.filter(x => x.type !== 'none')

.map(x => `${x.name}@${x.newVersion}`);

// unattributed contributions

const unattributed = Object.values(commits).filter(x => !x.changeset);

return { packages, changes, contributors, first, unattributed };

}

function formatPackagesChanged(packages) {

return `The following packages have been updated

%%%

${packages.join('\n')}

%%%`.replace(/%/g, '`');

}

function formatChange({ packages, summary, pull, user }) {

return `- \`[${packages.join(', ')}]\` ${summary} (#${pull}) @${user}`;

}

async function generateGitHubReleaseText(previousTag) {

if (!previousTag) throw new Error('Missing tag');

const { packages, changes, contributors, first, unattributed } = await fetchData(previousTag);

const output = [];

output.push(formatPackagesChanged(packages));

output.push('');

const breaking = changes.filter(x => x.type === 'major');

const features = changes.filter(x => x.type === 'minor');

const fixes = changes.filter(x => x.type === 'patch');

if (breaking.length) {

output.push(...[`#### Breaking Changes`, ...breaking.map(formatChange), ``]);

}

if (features.length) {

output.push(...[`#### New Features`, ...features.map(formatChange), ``]);

}

if (fixes.length) {

output.push(...[`#### Bug Fixes`, ...fixes.map(formatChange), ``]);

}

if (first.length || unattributed.length) {

const listh = unattributed.map(

({ user, pull }) =>

`@${user} ([#${pull}](https://github.com/keystonejs/keystone/pull/${pull}))`

);

const listf = first.map(

({ user, pull }) =>

`@${user} ([#${pull}](https://github.com/keystonejs/keystone/pull/${pull}))`

);

output.push(`#### Acknowledgements :blue_heart:`);

if (listh.length && listf.length) {

output.push(

`Thanks to ${listf.join(

', '

)} for their first contributions to the project, and a shoutout to ${listh.join(

', '

)} for their help.`

);

} else if (listh.length) {

output.push(`Thanks to ${listh.join(', ')} for their contributions to the project.`);

} else if (listf.length) {

output.push(

`Thanks to ${listf.join(', ')} for making their first contributions to the project!`

);

}

output.push(``);

}

const date = new Date().toISOString().slice(0, 10);

writeFileSync('./.changeset/contributors.json', JSON.stringify(contributors.sort(), null, 2));

writeFileSync(`./.changeset/release-${date}.md`, output.join('\n'));

console.error('files written to .changeset/');

}

generateGitHubReleaseText(process.argv[2]);