<?php
// Copyright 2004-present Facebook. All Rights Reserved.
//
// 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.

namespace Facebook\WebDriver\Remote;

use Facebook\WebDriver\WebDriver;
use Facebook\WebDriver\WebDriverAlert;
use Facebook\WebDriver\WebDriverElement;
use Facebook\WebDriver\WebDriverTargetLocator;

/**
 * Used to locate a given frame or window for RemoteWebDriver.
 */
class RemoteTargetLocator implements WebDriverTargetLocator
{
    /**
     * @var ExecuteMethod
     */
    protected $executor;
    /**
     * @var WebDriver
     */
    protected $driver;

    public function __construct($executor, $driver)
    {
        $this->executor = $executor;
        $this->driver = $driver;
    }

    /**
     * Switch to the main document if the page contains iframes. Otherwise, switch
     * to the first frame on the page.
     *
     * @return WebDriver The driver focused on the top window or the first frame.
     */
    public function defaultContent()
    {
        $params = ['id' => null];
        $this->executor->execute(DriverCommand::SWITCH_TO_FRAME, $params);

        return $this->driver;
    }

    /**
     * Switch to the iframe by its id or name.
     *
     * @param WebDriverElement|string $frame The WebDriverElement,
     * the id or the name of the frame.
     * @return WebDriver The driver focused on the given frame.
     */
    public function frame($frame)
    {
        if ($frame instanceof WebDriverElement) {
            $id = ['ELEMENT' => $frame->getID()];
        } else {
            $id = (string) $frame;
        }

        $params = ['id' => $id];
        $this->executor->execute(DriverCommand::SWITCH_TO_FRAME, $params);

        return $this->driver;
    }

    /**
     * Switch the focus to another window by its handle.
     *
     * @param string $handle The handle of the window to be focused on.
     * @return WebDriver The driver focused on the given window.
     * @see WebDriver::getWindowHandles
     */
    public function window($handle)
    {
        $params = ['name' => (string) $handle];
        $this->executor->execute(DriverCommand::SWITCH_TO_WINDOW, $params);

        return $this->driver;
    }

    /**
     * Switch to the currently active modal dialog for this particular driver
     * instance.
     *
     * @return WebDriverAlert
     */
    public function alert()
    {
        return new WebDriverAlert($this->executor);
    }

    /**
     * Switches to the element that currently has focus within the document
     * currently "switched to", or the body element if this cannot be detected.
     *
     * @return RemoteWebElement
     */
    public function activeElement()
    {
        $response = $this->driver->execute(DriverCommand::GET_ACTIVE_ELEMENT, []);
        $method = new RemoteExecuteMethod($this->driver);

        return new RemoteWebElement($method, $response['ELEMENT']);
    }
}