import { describe, expect, test } from 'bun:test';

import {
  buildClickScript,
  buildInspectScript,
  buildScrollScript,
  buildSnapshotScript,
  buildTypeScript,
} from './pageActions';

/**
 * These scripts are source text evaluated inside another page: nothing
 * type-checks them, and a value interpolated without escaping either breaks the
 * script or runs as code.
 */
const parses = (source: string): boolean => {
  try {
    new Function(source);
    return true;
  } catch {
    return false;
  }
};

describe('page action scripts', () => {
  test('every script parses', () => {
    expect(parses(buildSnapshotScript())).toBe(true);
    expect(parses(buildSnapshotScript({ selector: '#main' }))).toBe(true);
    expect(parses(buildClickScript({ selector: '#save' }))).toBe(true);
    expect(parses(buildClickScript({ text: 'Save' }))).toBe(true);
    expect(parses(buildTypeScript({ selector: '#q', value: 'hello', submit: true }))).toBe(true);
    expect(parses(buildInspectScript({ selector: '#save' }))).toBe(true);
    expect(parses(buildScrollScript({ direction: 'bottom' }))).toBe(true);
    expect(parses(buildScrollScript({ selector: 'footer' }))).toBe(true);
  });

  test('a hostile selector is embedded as data, not as code', () => {
    const hostile = `'); window.__owned = true; ('`;
    const script = buildClickScript({ selector: hostile });
    expect(parses(script)).toBe(true);
    // Present only inside a quoted literal: that is what makes it inert.
    expect(script).toContain(JSON.stringify(hostile));
  });

  test('a typed value is embedded as data too', () => {
    const value = '"); alert(1); ("';
    const script = buildTypeScript({ selector: '#q', value, submit: false });
    expect(parses(script)).toBe(true);
    expect(script).toContain(JSON.stringify(value));
  });

  test('whitespace regexes survive interpolation', () => {
    // A doubled backslash here would produce a literal backslash-s and match
    // nothing, silently collapsing no whitespace at all.
    expect(buildSnapshotScript()).toContain('replace(/\\s+/g');
  });

  test('scrolling asks for instant behaviour, not the page preference', () => {
    // A page with scroll-behavior: smooth would otherwise still be animating
    // when the position is read.
    expect(buildScrollScript({ direction: 'bottom' })).toContain("behavior: 'instant'");
    expect(buildScrollScript({ selector: 'footer' })).toContain("behavior: 'instant'");
  });

  test('a scoped snapshot reads only the subtree it was given', () => {
    const script = buildSnapshotScript({ selector: '#changelog' });
    expect(script).toContain('"#changelog"');
    expect(script).toContain('root.querySelectorAll');
  });
});