import { describe, expect, it } from 'vitest';

import {
  LOCAL_GAME_PREVIEW_SIZE_MESSAGE,
  parseLocalGamePreviewContentSize,
  resolveLocalGamePreviewContentSizeUpdate,
  resolveLocalGamePreviewFitLayout,
} from '../src/features/project-workspace/LocalGamePreviewFrame';

describe('local game preview viewport fitting', () => {
  it('keeps a game at native size when its content fits', () => {
    expect(
      resolveLocalGamePreviewFitLayout(
        { width: 1200, height: 700 },
        {
          contentWidth: 1200,
          contentHeight: 700,
          viewportWidth: 1200,
          viewportHeight: 700,
        },
      ),
    ).toEqual({ width: 1200, height: 700, scale: 1 });
  });

  it('scales the complete game document into the available viewport', () => {
    expect(
      resolveLocalGamePreviewFitLayout(
        { width: 1200, height: 700 },
        {
          contentWidth: 1200,
          contentHeight: 1000,
          viewportWidth: 1200,
          viewportHeight: 700,
        },
      ),
    ).toEqual({ width: 1200, height: 1000, scale: 0.7 });
  });

  it('accepts the native viewport report and keeps viewport out of fit state', () => {
    const nativeViewport = { width: 1200, height: 700 };
    const report = {
      contentWidth: 1200,
      contentHeight: 1000,
      viewportWidth: 1200,
      viewportHeight: 700,
    };

    expect(
      resolveLocalGamePreviewContentSizeUpdate(
        null,
        report,
        nativeViewport,
        nativeViewport,
      ),
    ).toEqual(report);
  });

  it('accepts changed content after the iframe has adopted the first fit viewport', () => {
    const nativeViewport = { width: 1200, height: 700 };
    const current = {
      contentWidth: 1200,
      contentHeight: 1000,
      viewportWidth: 1200,
      viewportHeight: 700,
    };
    const changed = {
      contentWidth: 1200,
      contentHeight: 1400,
      viewportWidth: 1200,
      viewportHeight: 1000,
    };

    expect(
      resolveLocalGamePreviewContentSizeUpdate(
        current,
        changed,
        nativeViewport,
        {
          width: 1200,
          height: 1000,
        },
      ),
    ).toEqual({
      contentWidth: 1200,
      contentHeight: 1400,
      viewportWidth: 1200,
      viewportHeight: 700,
    });
  });

  it('shrinks the fitted frame when content becomes shorter inside the applied viewport', () => {
    const nativeViewport = { width: 1200, height: 700 };
    const current = {
      contentWidth: 1200,
      contentHeight: 1000,
      viewportWidth: 1200,
      viewportHeight: 700,
    };
    const changed = {
      contentWidth: 1200,
      contentHeight: 800,
      viewportWidth: 1200,
      viewportHeight: 1000,
    };

    const updated = resolveLocalGamePreviewContentSizeUpdate(
      current,
      changed,
      nativeViewport,
      { width: 1200, height: 1000 },
    );
    expect(updated).toEqual({
      contentWidth: 1200,
      contentHeight: 800,
      viewportWidth: 1200,
      viewportHeight: 700,
    });
    expect(resolveLocalGamePreviewFitLayout(nativeViewport, updated)).toEqual({
      width: 1200,
      height: 800,
      scale: 0.875,
    });
  });

  it('keeps the current state for repeated content dimensions and fit viewport feedback', () => {
    const nativeViewport = { width: 1200, height: 700 };
    const current = {
      contentWidth: 1200,
      contentHeight: 1400,
      viewportWidth: 1200,
      viewportHeight: 700,
    };

    expect(
      resolveLocalGamePreviewContentSizeUpdate(
        current,
        { ...current, viewportHeight: 1400 },
        nativeViewport,
        { width: 1200, height: 1400 },
      ),
    ).toBe(current);
  });

  it('ignores delayed reports from a stale fitted viewport', () => {
    const nativeViewport = { width: 1200, height: 700 };
    const current = {
      contentWidth: 1200,
      contentHeight: 1400,
      viewportWidth: 1200,
      viewportHeight: 700,
    };

    expect(
      resolveLocalGamePreviewContentSizeUpdate(
        current,
        {
          contentWidth: 1200,
          contentHeight: 1100,
          viewportWidth: 1200,
          viewportHeight: 1000,
        },
        nativeViewport,
        { width: 1200, height: 1400 },
      ),
    ).toBe(current);
  });

  it('rejects malformed or unrelated cross-frame messages', () => {
    expect(
      parseLocalGamePreviewContentSize({
        type: LOCAL_GAME_PREVIEW_SIZE_MESSAGE,
        contentWidth: 1200,
        contentHeight: Number.NaN,
        viewportWidth: 1200,
        viewportHeight: 700,
      }),
    ).toBeNull();
    expect(
      parseLocalGamePreviewContentSize({
        type: 'unrelated',
        contentWidth: 1200,
        contentHeight: 700,
        viewportWidth: 1200,
        viewportHeight: 700,
      }),
    ).toBeNull();
  });
});