import { codeBlock } from 'common-tags';
import { mock } from 'vitest-mock-extended';
import { fakeSha, fs, git, platform } from '~test/util.ts';
import * as bitbucketserver from '../../../../modules/platform/bitbucket-server/index.ts';
import * as gitlab from '../../../../modules/platform/gitlab/index.ts';
import type { Pr } from '../../../../modules/platform/index.ts';
import { codeOwnersForPr } from './code-owners.ts';

vi.mock('../../../../util/fs/index.ts');

describe('workers/repository/update/pr/code-owners', () => {
  beforeAll(() => {
    Object.defineProperty(platform, 'extractRulesFromCodeOwnersLines', {
      value: undefined,
      writable: true,
    });
  });

  describe('codeOwnersForPr', () => {
    let pr: Pr;

    beforeEach(() => {
      pr = mock<Pr>();
      pr.sha = undefined;
    });

    it('returns global code owner', async () => {
      fs.readLocalFile.mockResolvedValueOnce(['* @jimmy'].join('\n'));
      git.getBranchFiles.mockResolvedValueOnce(['README.md']);
      const codeOwners = await codeOwnersForPr(pr);
      expect(codeOwners).toEqual(['@jimmy']);
    });

    it('returns global code owner for commit with sha set', async () => {
      pr.sha = fakeSha('f7374c2de8a4c95a7fd7182ab24044e3896aac02');
      fs.readLocalFile.mockResolvedValueOnce('* @jimmy');
      git.getBranchFilesFromCommit.mockResolvedValueOnce(['README.md']);
      const codeOwners = await codeOwnersForPr(pr);
      expect(codeOwners).toEqual(['@jimmy']);
    });

    it('respects orphan files', async () => {
      fs.readLocalFile.mockResolvedValueOnce(
        codeBlock`
          * @jimmy
          yarn.lock
        `,
      );
      git.getBranchFiles.mockResolvedValueOnce(['yarn.lock']);
      const codeOwners = await codeOwnersForPr(pr);
      expect(codeOwners).toEqual([]);
    });

    it('does not return any owners if PR has no changes', async () => {
      fs.readLocalFile.mockResolvedValueOnce('* @jimmy');
      git.getBranchFiles.mockResolvedValueOnce([]);
      const codeOwners = await codeOwnersForPr(pr);
      expect(codeOwners).toEqual([]);
    });

    it('returns more specific code owners', async () => {
      fs.readLocalFile.mockResolvedValueOnce(
        ['* @jimmy', 'package.json @john @maria'].join('\n'),
      );
      git.getBranchFiles.mockResolvedValueOnce(['package.json']);
      const codeOwners = await codeOwnersForPr(pr);
      expect(codeOwners).toEqual(['@john', '@maria', '@jimmy']);
    });

    describe('returns more specific code owners in monorepos', () => {
      const mockCodeOwners = codeBlock`
        # By default, assign to @john
        #
        * @john

        # Lockfiles are not owned by anyone, any package dependency update may modify them.
        # Assigning lockfiles an owner will cause issues as merge requests to be assigned to incorrect users
        yarn.lock

        # Assign each package to its respective user
        #
        packages/a/ @maria
        packages/b/ @jimmy
        packages/c/ @dan
        packages/d/ @maria @jimmy
        packages/e/ @jimmy

      `;

      it('does not assign changes for yarn.lock', async () => {
        fs.readLocalFile.mockResolvedValueOnce(mockCodeOwners);
        git.getBranchFiles.mockResolvedValueOnce(['yarn.lock']);
        const codeOwners = await codeOwnersForPr(pr);
        expect(codeOwners).toEqual([]);
      });

      it('assigns root changes to @john (*)', async () => {
        fs.readLocalFile.mockResolvedValueOnce(mockCodeOwners);
        git.getBranchFiles.mockResolvedValueOnce(['package.json', 'yarn.lock']);
        const codeOwners = await codeOwnersForPr(pr);
        expect(codeOwners).toEqual(['@john']);
      });

      it('assigns changes in package A to @maria (a), @john (*)', async () => {
        fs.readLocalFile.mockResolvedValueOnce(mockCodeOwners);
        git.getBranchFiles.mockResolvedValueOnce([
          'packages/a/package.json',
          'yarn.lock',
        ]);
        const codeOwners = await codeOwnersForPr(pr);
        expect(codeOwners).toEqual(['@maria', '@john']);
      });

      it('assigns changes in package B to @jimmy (b), @john (*)', async () => {
        fs.readLocalFile.mockResolvedValueOnce(mockCodeOwners);
        git.getBranchFiles.mockResolvedValueOnce([
          'packages/b/package.json',
          'yarn.lock',
        ]);
        const codeOwners = await codeOwnersForPr(pr);
        expect(codeOwners).toEqual(['@jimmy', '@john']);
      });

      it('assigns changes in package C to @dan (c), @john (*)', async () => {
        fs.readLocalFile.mockResolvedValueOnce(mockCodeOwners);
        git.getBranchFiles.mockResolvedValueOnce([
          'packages/c/package.json',
          'yarn.lock',
        ]);
        const codeOwners = await codeOwnersForPr(pr);
        expect(codeOwners).toEqual(['@dan', '@john']);
      });

      it('assigns changes in package D to @maria (d), @jimmy (d), @john (*)', async () => {
        fs.readLocalFile.mockResolvedValueOnce(mockCodeOwners);
        git.getBranchFiles.mockResolvedValueOnce([
          'packages/d/package.json',
          'yarn.lock',
        ]);
        const codeOwners = await codeOwnersForPr(pr);
        expect(codeOwners).toEqual(['@maria', '@jimmy', '@john']);
      });

      it('assigns changes in package A and B to @maria (a), @jimmy (b), @john (*)', async () => {
        fs.readLocalFile.mockResolvedValueOnce(mockCodeOwners);
        git.getBranchFiles.mockResolvedValueOnce([
          'packages/a/package.json',
          'packages/b/package.json',
          'yarn.lock',
        ]);
        const codeOwners = await codeOwnersForPr(pr);
        expect(codeOwners).toEqual(['@maria', '@jimmy', '@john']);
      });

      it('assigns changes in package A, B and C to @john, @maria (a), @jimmy (b), @dan (c), @john (*)', async () => {
        fs.readLocalFile.mockResolvedValueOnce(mockCodeOwners);
        git.getBranchFiles.mockResolvedValueOnce([
          'packages/a/package.json',
          'packages/b/package.json',
          'packages/c/package.json',
          'yarn.lock',
        ]);
        const codeOwners = await codeOwnersForPr(pr);
        expect(codeOwners).toEqual(['@maria', '@jimmy', '@dan', '@john']);
      });

      it('assigns changes in package C and D to @dan (c), @maria (d), @jimmy (e), @john (*)', async () => {
        fs.readLocalFile.mockResolvedValueOnce(mockCodeOwners);
        git.getBranchFiles.mockResolvedValueOnce([
          'packages/c/package.json',
          'packages/d/package.json',
          'yarn.lock',
        ]);
        const codeOwners = await codeOwnersForPr(pr);
        expect(codeOwners).toEqual(['@dan', '@maria', '@jimmy', '@john']);
      });

      it('assigns changes in package D and E to @jimmy (d, e), @maria (d), @john (*)', async () => {
        fs.readLocalFile.mockResolvedValueOnce(mockCodeOwners);
        git.getBranchFiles.mockResolvedValueOnce([
          'packages/d/package.json',
          'packages/e/package.json',
          'yarn.lock',
        ]);
        const codeOwners = await codeOwnersForPr(pr);
        expect(codeOwners).toEqual(['@jimmy', '@maria', '@john']);
      });
    });

    describe('supports Gitlab sections', () => {
      beforeAll(() => {
        Object.defineProperty(platform, 'extractRulesFromCodeOwnersLines', {
          value: gitlab.extractRulesFromCodeOwnersLines,
          writable: true,
        });
      });

      it('returns section code owner', async () => {
        fs.readLocalFile.mockResolvedValueOnce(
          ['[team] @jimmy', '*'].join('\n'),
        );
        git.getBranchFiles.mockResolvedValueOnce(['README.md']);

        const codeOwners = await codeOwnersForPr(pr);

        expect(codeOwners).toEqual(['@jimmy']);
      });

      const codeOwnerFileWithDefaultApproval = codeBlock`
            # Required for all files
            * @general-approvers

            [Documentation] @docs-team
            docs/
            README.md
            *.txt

            # Invalid section
            Something before [Tests] @tests-team
            tests/

            # Optional section
            ^[Optional] @optional-team
            optional/

            [Database] @database-team
            model/db/
            config/db/database-setup.md @docs-team
          `;

      it('returns code owners of multiple sections', async () => {
        fs.readLocalFile.mockResolvedValueOnce(
          codeOwnerFileWithDefaultApproval,
        );
        git.getBranchFiles.mockResolvedValueOnce([
          'config/db/database-setup.md',
        ]);

        const codeOwners = await codeOwnersForPr(pr);

        expect(codeOwners).toEqual(['@docs-team', '@general-approvers']);
      });

      it('returns default owners when none is explicitly set', async () => {
        fs.readLocalFile.mockResolvedValueOnce(
          codeOwnerFileWithDefaultApproval,
        );
        git.getBranchFiles.mockResolvedValueOnce(['model/db/CHANGELOG.txt']);

        const codeOwners = await codeOwnersForPr(pr);

        expect(codeOwners).toEqual([
          '@database-team',
          '@docs-team',
          '@general-approvers',
        ]);
      });

      it('parses only sections that start at the beginning of a line', async () => {
        fs.readLocalFile.mockResolvedValueOnce(
          codeOwnerFileWithDefaultApproval,
        );
        git.getBranchFiles.mockResolvedValueOnce(['tests/setup.ts']);

        const codeOwners = await codeOwnersForPr(pr);

        expect(codeOwners).not.toInclude('@tests-team');
      });

      it('returns code owners for optional sections', async () => {
        fs.readLocalFile.mockResolvedValueOnce(
          codeOwnerFileWithDefaultApproval,
        );
        git.getBranchFiles.mockResolvedValueOnce([
          'optional/optional-file.txt',
        ]);

        const codeOwners = await codeOwnersForPr(pr);

        expect(codeOwners).toEqual([
          '@optional-team',
          '@docs-team',
          '@general-approvers',
        ]);
      });
    });

    describe('Bitbucket Server CODEOWNERS integration', () => {
      beforeAll(() => {
        Object.defineProperty(platform, 'extractRulesFromCodeOwnersLines', {
          value: bitbucketserver.extractRulesFromCodeOwnersLines,
          writable: true,
        });
      });

      it('returns code owners for matching file using escaped spaces', async () => {
        fs.readLocalFile.mockResolvedValueOnce(
          String.raw`src/** @Jane\\ Doe @john@example.com`,
        );
        git.getBranchFiles.mockResolvedValueOnce(['src/index.ts']);

        const codeOwners = await codeOwnersForPr(pr);

        expect(codeOwners).toEqual(['@Jane Doe', '@john@example.com']);
      });

      it('returns code owners from reviewer group with random selection', async () => {
        fs.readLocalFile.mockResolvedValueOnce(
          'docs/** @reviewer-group/content-designers:random',
        );
        git.getBranchFiles.mockResolvedValueOnce(['docs/readme.md']);

        const codeOwners = await codeOwnersForPr(pr);

        // Since we don't simulate the actual group resolution, this will just include the literal string
        expect(codeOwners).toEqual([
          '@reviewer-group/content-designers:random',
        ]);
      });

      it('does not return owners when an empty rule overrides a broader rule', async () => {
        fs.readLocalFile.mockResolvedValueOnce(
          [
            'docs/images/**', // empty rule
            'docs/** @content-designer',
          ].join('\n'),
        );
        git.getBranchFiles.mockResolvedValueOnce(['docs/images/logo.png']);

        const codeOwners = await codeOwnersForPr(pr);

        expect(codeOwners).toEqual([]);
      });

      it('matches the most specific rule (bottom takes precedence)', async () => {
        fs.readLocalFile.mockResolvedValueOnce(
          [
            'docs/** @team1',
            'docs/backend/** @team2', // higher precedence
          ].join('\n'),
        );
        git.getBranchFiles.mockResolvedValueOnce(['docs/backend/service.md']);

        const codeOwners = await codeOwnersForPr(pr);

        expect(codeOwners).toEqual(['@team2', '@team1']);
      });

      it('handles multiple owners with mix of usernames and groups', async () => {
        fs.readLocalFile.mockResolvedValueOnce(
          'docs/** @Alice @reviewer-group/devs:random(2)',
        );
        git.getBranchFiles.mockResolvedValueOnce(['docs/manual.md']);

        const codeOwners = await codeOwnersForPr(pr);

        expect(codeOwners).toEqual([
          '@Alice',
          '@reviewer-group/devs:random(2)',
        ]);
      });
    });

    it.fails('does not parse Gitea regex as Gitlab sections', async () => {
      Object.defineProperty(platform, 'extractRulesFromCodeOwnersLines', {
        value: undefined,
        writable: true,
      });
      fs.readLocalFile.mockResolvedValueOnce(
        codeBlock`
          # This is a regex, not a Gitlab section, so 002-file.md should be assigned to @reviewer-03
          [0-3].*/*.md$ @reviewer-03
          002-file.md

          [4-9].*/*.md$ @reviewer-49
        `,
      );
      git.getBranchFiles.mockResolvedValueOnce(['001-file.md', '002-file.md']);

      const codeOwners = await codeOwnersForPr(pr);

      expect(codeOwners).toEqual(['@reviewer-03']);
    });

    it('does not require all files to match a single rule, regression test for #12611', async () => {
      fs.readLocalFile.mockResolvedValueOnce(
        codeBlock`
          * @reviewer-1 @reviewer-2 @reviewer-3 @reviewer-4 @reviewer-5

          server/pom.xml @reviewer-1
          client/package.json @reviewer-1
          client/package-lock.json @reviewer-1
        `,
      );
      git.getBranchFiles.mockResolvedValueOnce(['server/pom.xml']);
      const codeOwners = await codeOwnersForPr(pr);
      expect(codeOwners).toEqual([
        '@reviewer-1', // matched by file
        '@reviewer-2', // matched by wildcard
        '@reviewer-3',
        '@reviewer-4',
        '@reviewer-5',
      ]);

      fs.readLocalFile.mockResolvedValueOnce(
        codeBlock`
          * @reviewer-1 @reviewer-2 @reviewer-3 @reviewer-4 @reviewer-5

          server/pom.xml @reviewer-1
          client/package.json @reviewer-1
          client/package-lock.json @reviewer-1
        `,
      );
      git.getBranchFiles.mockResolvedValueOnce([
        'client/package.json',
        'client/package-lock.json',
      ]);
      const codeOwners2 = await codeOwnersForPr(pr);
      expect(codeOwners2).toEqual([
        '@reviewer-1', // matched by file
        '@reviewer-2', // matched by wildcard
        '@reviewer-3',
        '@reviewer-4',
        '@reviewer-5',
      ]);
    });

    it('ignores comments and leading/trailing whitespace', async () => {
      fs.readLocalFile.mockResolvedValueOnce(
        [
          '# comment line',
          '    \t    ',
          '   * @jimmy     # inline comment     ',
          '        # comment line with leading whitespace',
          ' package.json @john @maria#inline comment without leading whitespace  ',
        ].join('\n'),
      );
      git.getBranchFiles.mockResolvedValueOnce(['package.json']);
      const codeOwners = await codeOwnersForPr(pr);
      expect(codeOwners).toEqual(['@john', '@maria', '@jimmy']);
    });

    it('returns empty array when no code owners set', async () => {
      fs.readLocalFile.mockResolvedValueOnce(null);
      git.getBranchFiles.mockResolvedValueOnce(['package.json']);
      const codeOwners = await codeOwnersForPr(pr);
      expect(codeOwners).toBeEmptyArray();
    });

    it('returns empty array when no code owners match', async () => {
      fs.readLocalFile.mockResolvedValueOnce(
        ['package-lock.json @mike'].join('\n'),
      );
      git.getBranchFiles.mockResolvedValueOnce(['yarn.lock']);
      const codeOwners = await codeOwnersForPr(pr);
      expect(codeOwners).toEqual([]);
    });

    it('returns empty array when error occurs', async () => {
      fs.readLocalFile.mockRejectedValueOnce(new Error());
      const codeOwners = await codeOwnersForPr(pr);
      expect(codeOwners).toBeEmptyArray();
    });

    const codeOwnerFilePaths = [
      'CODEOWNERS',
      '.github/CODEOWNERS',
      '.gitlab/CODEOWNERS',
      'docs/CODEOWNERS',
    ];
    codeOwnerFilePaths.forEach((codeOwnerFilePath) => {
      it(`detects code owner file at '${codeOwnerFilePath}'`, async () => {
        fs.readLocalFile.mockImplementation((path): Promise<any> => {
          if (path === codeOwnerFilePath) {
            return Promise.resolve(['* @mike'].join('\n'));
          }
          return Promise.resolve(null);
        });
        git.getBranchFiles.mockResolvedValueOnce(['README.md']);
        const codeOwners = await codeOwnersForPr(pr);
        expect(codeOwners).toEqual(['@mike']);
      });
    });
  });
});