/*
 * Copyright (C) 2013 DroidDriver committers
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.android.droiddriver.base;

import android.app.Instrumentation;
import android.graphics.Bitmap;
import android.graphics.Bitmap.CompressFormat;
import android.util.Log;

import com.google.android.droiddriver.DroidDriver;
import com.google.android.droiddriver.Poller;
import com.google.android.droiddriver.Screenshotter;
import com.google.android.droiddriver.UiElement;
import com.google.android.droiddriver.exceptions.ElementNotFoundException;
import com.google.android.droiddriver.exceptions.TimeoutException;
import com.google.android.droiddriver.finders.ByXPath;
import com.google.android.droiddriver.finders.Finder;
import com.google.android.droiddriver.util.DefaultPoller;
import com.google.android.droiddriver.util.FileUtils;
import com.google.android.droiddriver.util.Logs;
import com.google.common.base.Preconditions;

import java.io.BufferedOutputStream;

/**
 * Abstract implementation of DroidDriver that does the common actions, and
 * should not differ in implementations of {@link DroidDriver}.
 */
public abstract class AbstractDroidDriver implements DroidDriver, Screenshotter {

  protected final Instrumentation instrumentation;
  private Poller poller = new DefaultPoller();
  private AbstractUiElement rootElement;

  protected AbstractDroidDriver(Instrumentation instrumentation) {
    this.instrumentation = Preconditions.checkNotNull(instrumentation);
  }

  @Override
  public UiElement find(Finder finder) {
    Logs.call(this, "find", finder);
    return finder.find(refreshRootElement());
  }

  @Override
  public boolean has(Finder finder) {
    try {
      find(finder);
      return true;
    } catch (ElementNotFoundException enfe) {
      return false;
    }
  }

  @Override
  public boolean has(Finder finder, long timeoutMillis) {
    try {
      getPoller().pollFor(this, finder, Poller.EXISTS, timeoutMillis);
      return true;
    } catch (TimeoutException e) {
      return false;
    }
  }

  @Override
  public UiElement on(Finder finder) {
    Logs.call(this, "on", finder);
    return getPoller().pollFor(this, finder, Poller.EXISTS);
  }

  @Override
  public void checkExists(Finder finder) {
    Logs.call(this, "checkExists", finder);
    getPoller().pollFor(this, finder, Poller.EXISTS);
  }

  @Override
  public void checkGone(Finder finder) {
    Logs.call(this, "checkGone", finder);
    getPoller().pollFor(this, finder, Poller.GONE);
  }

  @Override
  public Poller getPoller() {
    return poller;
  }

  @Override
  public void setPoller(Poller poller) {
    this.poller = poller;
  }

  protected abstract AbstractUiElement getNewRootElement();

  protected abstract AbstractContext getContext();

  protected AbstractUiElement getRootElement() {
    if (rootElement == null) {
      refreshRootElement();
    }
    return rootElement;
  }

  private AbstractUiElement refreshRootElement() {
    getContext().clearData();
    rootElement = getNewRootElement();
    return rootElement;
  }

  @Override
  public boolean dumpUiElementTree(String path) {
    Logs.call(this, "dumpUiElementTree", path);
    return ByXPath.dumpDom(path, getRootElement());
  }

  @Override
  public boolean takeScreenshot(String path) {
    return takeScreenshot(path, Bitmap.CompressFormat.PNG, 0);
  }

  @Override
  public boolean takeScreenshot(String path, CompressFormat format, int quality) {
    Logs.call(this, "takeScreenshot", path, quality);
    Bitmap screenshot = takeScreenshot();
    if (screenshot == null) {
      return false;
    }
    BufferedOutputStream bos = null;
    try {
      bos = FileUtils.open(path);
      screenshot.compress(format, quality, bos);
      return true;
    } catch (Exception e) {
      Logs.log(Log.WARN, e);
      return false;
    } finally {
      if (bos != null) {
        try {
          bos.close();
        } catch (Exception e) {
          // ignore
        }
      }
      screenshot.recycle();
    }
  }

  protected abstract Bitmap takeScreenshot();
}