import { GitProcess, IGitExecutionOptions, IGitResult } from 'dugite';
import { expect } from 'chai';
import * as notes from '../script/release/notes/notes.js';
import * as path from 'path';
import * as sinon from 'sinon';

/* Fake a Dugite GitProcess that only returns the specific
   commits that we want to test */

class Commit {
  sha1: string;
  subject: string;
  constructor (sha1: string, subject: string) {
    this.sha1 = sha1;
    this.subject = subject;
  }
}

class GitFake {
  branches: {
    [key: string]: Commit[],
  };

  constructor () {
    this.branches = {};
  }

  setBranch (name: string, commits: Array<Commit>): void {
    this.branches[name] = commits;
  }

  // find the newest shared commit between branches a and b
  mergeBase (a: string, b:string): string {
    for (const commit of [ ...this.branches[a].reverse() ]) {
      if (this.branches[b].map((commit: Commit) => commit.sha1).includes(commit.sha1)) {
        return commit.sha1;
      }
    }
    console.error('test error: branches not related');
    return '';
  }

  // eslint-disable-next-line @typescript-eslint/no-unused-vars
  exec (args: string[], path: string, options?: IGitExecutionOptions | undefined): Promise<IGitResult> {
    let stdout = '';
    const stderr = '';
    const exitCode = 0;

    if (args.length === 3 && args[0] === 'merge-base') {
      // expected form: `git merge-base branchName1 branchName2`
      const a: string = args[1]!;
      const b: string = args[2]!;
      stdout = this.mergeBase(a, b);
    } else if (args.length === 3 && args[0] === 'log' && args[1] === '--format=%H') {
      // exepcted form: `git log --format=%H branchName
      const branch: string = args[2]!;
      stdout = this.branches[branch].map((commit: Commit) => commit.sha1).join('\n');
    } else if (args.length > 1 && args[0] === 'log' && args.includes('--format=%H,%s')) {
      // expected form: `git log --format=%H,%s sha1..branchName
      const [ start, branch ] = args[args.length - 1].split('..');
      const lines : string[] = [];
      let started = false;
      for (const commit of this.branches[branch]) {
        started = started || commit.sha1 === start;
        if (started) {
          lines.push(`${commit.sha1},${commit.subject}` /* %H,%s */);
        }
      }
      stdout = lines.join('\n');
    } else {
      console.error('unhandled GitProcess.exec():', args);
    }

    return Promise.resolve({ exitCode, stdout, stderr });
  }
}

describe('release notes', () => {
  const sandbox = sinon.createSandbox();
  const gitFake = new GitFake();

  const oldBranch = '8-x-y';
  const newBranch = '9-x-y';

  // commits shared by both oldBranch and newBranch
  const sharedHistory = [
    new Commit('2abea22b4bffa1626a521711bacec7cd51425818', "fix: explicitly cancel redirects when mode is 'error' (#20686)"),
    new Commit('467409458e716c68b35fa935d556050ca6bed1c4', 'build: add support for automated minor releases (#20620)') // merge-base
  ];

  // these commits came after newBranch was created
  const newBreaking = new Commit('2fad53e66b1a2cb6f7dad88fe9bb62d7a461fe98', 'refactor: use v8 serialization for ipc (#20214)');
  const newFeat = new Commit('89eb309d0b22bd4aec058ffaf983e81e56a5c378', 'feat: allow GUID parameter to avoid systray demotion on Windows  (#21891)');
  const newFix = new Commit('0600420bac25439fc2067d51c6aaa4ee11770577', "fix: don't allow window to go behind menu bar on mac (#22828)");
  const oldFix = new Commit('f77bd19a70ac2d708d17ddbe4dc12745ca3a8577', 'fix: prevent menu gc during popup (#20785)');

  // a bug that's fixed in both branches by separate PRs
  const newTropFix = new Commit('a6ff42c190cb5caf8f3e217748e49183a951491b', 'fix: workaround for hang when preventDefault-ing nativeWindowOpen (#22750)');
  const oldTropFix = new Commit('8751f485c5a6c8c78990bfd55a4350700f81f8cd', 'fix: workaround for hang when preventDefault-ing nativeWindowOpen (#22749)');

  before(() => {
    // location of relase-notes' octokit reply cache
    const fixtureDir = path.resolve(__dirname, 'fixtures', 'release-notes');
    process.env.NOTES_CACHE_PATH = path.resolve(fixtureDir, 'cache');
  });

  beforeEach(() => {
    const wrapper = (args: string[], path: string, options?: IGitExecutionOptions | undefined) => gitFake.exec(args, path, options);
    sandbox.replace(GitProcess, 'exec', wrapper);

    gitFake.setBranch(oldBranch, [ ...sharedHistory, oldFix ]);
  });

  afterEach(() => {
    sandbox.restore();
  });

  describe('changes that exist in older branches', () => {
    // use case: this fix is NOT news because it was already fixed
    // while oldBranch was the latest stable release
    it('are skipped if the target version is a new major line (x.0.0)', async function () {
      const version = 'v9.0.0';
      gitFake.setBranch(oldBranch, [ ...sharedHistory, oldTropFix ]);
      gitFake.setBranch(newBranch, [ ...sharedHistory, newTropFix ]);
      const results: any = await notes.get(oldBranch, newBranch, version);
      expect(results.fix).to.have.lengthOf(0);
    });

    // use case: this fix IS news because it's being fixed in
    // multiple stable branches at once, including newBranch.
    it('are included if the target version is a minor or patch bump', async function () {
      const version = 'v9.0.1';
      gitFake.setBranch(oldBranch, [ ...sharedHistory, oldTropFix ]);
      gitFake.setBranch(newBranch, [ ...sharedHistory, newTropFix ]);
      const results: any = await notes.get(oldBranch, newBranch, version);
      expect(results.fix).to.have.lengthOf(1);
    });
  });

  // use case: A malicious contributor could edit the text of their 'Notes:'
  // in the PR body after a PR's been merged and the maintainers have moved on.
  // So instead always use the release-clerk PR comment
  it('uses the release-clerk text', async function () {
    // realText source: ${fixtureDir}/electron-electron-issue-21891-comments
    const realText = 'Added GUID parameter to Tray API to avoid system tray icon demotion on Windows';
    const testCommit = new Commit('89eb309d0b22bd4aec058ffaf983e81e56a5c378', 'feat: lole u got troled hard (#21891)');
    const version = 'v9.0.0';

    gitFake.setBranch(newBranch, [ ...sharedHistory, testCommit ]);
    const results: any = await notes.get(oldBranch, newBranch, version);
    expect(results.feat).to.have.lengthOf(1);
    expect(results.feat[0].hash).to.equal(testCommit.sha1);
    expect(results.feat[0].note).to.equal(realText);
  });

  // test that when you feed in different semantic commit types,
  // the parser returns them in the results' correct category
  describe('semantic commit', () => {
    const version = 'v9.0.0';

    it("honors 'feat' type", async function () {
      const testCommit = newFeat;
      gitFake.setBranch(newBranch, [ ...sharedHistory, testCommit ]);
      const results: any = await notes.get(oldBranch, newBranch, version);
      expect(results.feat).to.have.lengthOf(1);
      expect(results.feat[0].hash).to.equal(testCommit.sha1);
    });

    it("honors 'fix' type", async function () {
      const testCommit = newFix;
      gitFake.setBranch(newBranch, [ ...sharedHistory, testCommit ]);
      const results: any = await notes.get(oldBranch, newBranch, version);
      expect(results.fix).to.have.lengthOf(1);
      expect(results.fix[0].hash).to.equal(testCommit.sha1);
    });

    it("honors 'BREAKING CHANGE' message", async function () {
      const testCommit = newBreaking;
      gitFake.setBranch(newBranch, [ ...sharedHistory, testCommit ]);
      const results: any = await notes.get(oldBranch, newBranch, version);
      expect(results.breaking).to.have.lengthOf(1);
      expect(results.breaking[0].hash).to.equal(testCommit.sha1);
    });
  });
});