/**
 * Global-install planner tests — covers the pure decision function
 * that turns "what's installed globally" + "what we're publishing" +
 * --track-alpha into a list of GlobalUpdateItems for the executor.
 *
 * The disk-reading wrapper (`planGlobalUpdate`) is a thin shim on top
 * of `decideGlobalUpdates`; testing the pure layer exercises all the
 * policy.
 */

import { describe, expect, test } from 'bun:test';
import { decideGlobalUpdates } from './global-install';

/** Helper for tests: pretend everything in the map is installed at the listed version. */
function installedVersionFrom(versions: Record<string, string>): (name: string) => string | null {
  return (name) => versions[name] ?? null;
}

describe('decideGlobalUpdates', () => {
  test('empty installed → empty plan', () => {
    expect(
      decideGlobalUpdates({
        installed: [],
        justPublished: [],
        trackAlpha: false,
        installedVersion: () => null,
      }),
    ).toEqual([]);
  });

  test('normal mode: force-pins just-published, update-pulls the rest', () => {
    const result = decideGlobalUpdates({
      installed: ['@celilo/cli', '@celilo/e2e', '@celilo/event-bus'],
      justPublished: [
        { name: '@celilo/cli', version: '0.4.0' },
        { name: '@celilo/e2e', version: '0.8.0' },
      ],
      trackAlpha: false,
      installedVersion: installedVersionFrom({
        '@celilo/cli': '0.3.0',
        '@celilo/e2e': '0.7.0',
        '@celilo/event-bus': '0.1.0',
      }),
    });

    expect(result).toEqual([
      {
        name: '@celilo/cli',
        installed: '0.3.0',
        target: '0.4.0',
        forcePin: true,
      },
      {
        name: '@celilo/e2e',
        installed: '0.7.0',
        target: '0.8.0',
        forcePin: true,
      },
      {
        name: '@celilo/event-bus',
        installed: '0.1.0',
        target: '0.1.0',
        forcePin: false,
      },
    ]);
  });

  test('--track-alpha filters to just-published only', () => {
    const result = decideGlobalUpdates({
      installed: ['@celilo/cli', '@celilo/e2e', '@celilo/event-bus'],
      justPublished: [{ name: '@celilo/e2e', version: '0.8.0-alpha.0' }],
      trackAlpha: true,
      installedVersion: installedVersionFrom({
        '@celilo/cli': '0.3.0',
        '@celilo/e2e': '0.7.0',
        '@celilo/event-bus': '0.1.0',
      }),
    });

    // Other globals (@celilo/cli, @celilo/event-bus) are left alone —
    // they may already be on their own alpha streams.
    expect(result).toHaveLength(1);
    expect(result[0]).toEqual({
      name: '@celilo/e2e',
      installed: '0.7.0',
      target: '0.8.0-alpha.0',
      forcePin: true,
    });
  });

  test('--track-alpha + nothing-just-published → empty plan', () => {
    expect(
      decideGlobalUpdates({
        installed: ['@celilo/cli', '@celilo/e2e'],
        justPublished: [],
        trackAlpha: true,
        installedVersion: installedVersionFrom({
          '@celilo/cli': '0.3.0',
          '@celilo/e2e': '0.7.0',
        }),
      }),
    ).toEqual([]);
  });

  test('handles missing installed version gracefully (target falls back to "?")', () => {
    const result = decideGlobalUpdates({
      installed: ['@celilo/cli'],
      justPublished: [],
      trackAlpha: false,
      installedVersion: () => null, // bun symlink missing, malformed pkg, etc.
    });

    expect(result).toEqual([
      {
        name: '@celilo/cli',
        installed: null,
        target: '?',
        forcePin: false,
      },
    ]);
  });

  test('preserves installed order', () => {
    const result = decideGlobalUpdates({
      installed: ['@celilo/event-bus', '@celilo/cli', '@celilo/e2e'],
      justPublished: [],
      trackAlpha: false,
      installedVersion: installedVersionFrom({
        '@celilo/event-bus': '0.1.0',
        '@celilo/cli': '0.3.0',
        '@celilo/e2e': '0.7.0',
      }),
    });

    expect(result.map((i) => i.name)).toEqual(['@celilo/event-bus', '@celilo/cli', '@celilo/e2e']);
  });

  test('just-published packages NOT in installed are not added (only refreshes existing globals)', () => {
    // Operator hasn't installed @celilo/cli globally, but the publish
    // run shipped it. We don't auto-install — we only refresh what's
    // already there. So @celilo/cli should NOT appear in the plan.
    const result = decideGlobalUpdates({
      installed: ['@celilo/e2e'],
      justPublished: [
        { name: '@celilo/cli', version: '0.4.0' },
        { name: '@celilo/e2e', version: '0.8.0' },
      ],
      trackAlpha: false,
      installedVersion: installedVersionFrom({ '@celilo/e2e': '0.7.0' }),
    });

    expect(result.map((i) => i.name)).toEqual(['@celilo/e2e']);
  });
});