#!/usr/bin/env python
# Copyright (c) 2012 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import logging
import os

import pyauto_functional  # Must be imported before pyauto
import pyauto


class GpuTest(pyauto.PyUITest):
  """GPU Tests Runner."""

  def _GetGpuPID(self):
    """Fetch the pid of the GPU process."""
    child_processes = self.GetBrowserInfo()['child_processes']
    for x in child_processes:
       if x['type'] == 'GPU':
         return x['pid']
    return None

  def _IsHardwareAccelerated(self, feature):
    """Check if gpu is enabled in the machine before running any tests."""
    self.NavigateToURL('about:gpu')
    def IsFeatureStatusLoaded():
      """Returns whether the feature status UI has been loaded.

      The about:gpu page fetches status for features asynchronously, so use
      this to check if the fetch is done.
      """
      js = """
        var list = document.querySelector(".feature-status-list");
        domAutomationController.send(list.hasChildNodes() ? "done" : "");
      """
      return self.ExecuteJavascript(js)
    self.assertTrue(self.WaitUntil(IsFeatureStatusLoaded, 10))
    search = feature + ': Hardware accelerated'
    find_result = self.FindInPage(search)['match_count']
    if find_result:
      # about:gpu page starts a gpu process. Restart the browser to clear
      # the state. We could kill the gpu process, but navigating to a page
      # after killing the gpu can lead to flakiness.
      # See crbug.com/93423.
      self.RestartBrowser()
      return True
    else:
      logging.warn('Hardware acceleration not available')
      return False

  def _VerifyGPUProcessOnPage(self, url):
    url = self.GetFileURLForDataPath('pyauto_private', 'gpu', url)
    self.NavigateToURL(url)
    self.assertTrue(self.WaitUntil(
      lambda: self._GetGpuPID() is not None), msg='No process for GPU')

  def testSingleGpuProcess(self):
    """Verify there's only one gpu process shared across all uses."""
    self.assertTrue(self._IsHardwareAccelerated('WebGL'))
    url = self.GetFileURLForDataPath('pyauto_private',
                                     'gpu', 'WebGLField.html')
    self.AppendTab(pyauto.GURL(url))
    # Open a new window.
    self.OpenNewBrowserWindow(True)
    self.NavigateToURL(url, 1, 0)
    # Open a new incognito window.
    self.RunCommand(pyauto.IDC_NEW_INCOGNITO_WINDOW)
    self.NavigateToURL(url, 1, 0)
    # Verify there's only 1 gpu process.
    gpu_process_count = 0
    for x in self.GetBrowserInfo()['child_processes']:
      if x['type'] == 'GPU':
        gpu_process_count += 1
    self.assertEqual(1, gpu_process_count)


if __name__ == '__main__':
  pyauto_functional.Main()