#!/usr/bin/python
#
# Copyright 2011 Software Freedom Conservancy.
#
# 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.

from selenium.common.exceptions import WebDriverException
from selenium.webdriver.common.by import By
from selenium.webdriver.remote.webdriver import WebDriver
from selenium.webdriver.remote.webelement import WebElement
from abstract_event_listener import AbstractEventListener


def _wrap_elements(result, ef_driver):
    if isinstance(result, WebElement):
        return EventFiringWebElement(result, ef_driver)
    elif isinstance(result, list):
        return [_wrap_elements(item, ef_driver) for item in result]
    else:
        return result

class EventFiringWebDriver(object):
    """
    A wrapper around an arbitrary WebDriver instance which supports firing events
    """
    
    def __init__(self, driver, event_listener):
        """
        Creates a new instance of the EventFiringWebDriver
        
        :Args:
         - driver : A WebDriver instance
         - event_listener : Instance of a class that subclasses AbstractEventListener and implements it fully or partially
        
        Example:

        .. code-block:: python

            from selenium.webdriver import Firefox
            from selenium.webdriver.support.events import EventFiringWebDriver, AbstractEventListener
            
            class MyListener(AbstractEventListener):
                def before_navigate_to(self, url, driver):
                    print "Before navigate to %s" % url
                def after_navigate_to(self, url, driver):
                    print "After navigate to %s" % url
            
            driver = Firefox()
            ef_driver = EventFiringWebDriver(driver, MyListener())
            ef_driver.get("http://www.google.co.in/")
        """
        if not isinstance(driver, WebDriver):
            raise WebDriverException("A WebDriver instance must be supplied")
        if not isinstance(event_listener, AbstractEventListener):
            raise WebDriverException("Event listener must be a subclass of AbstractEventListener")
        self._driver = driver
        self._listener = event_listener
        
    @property
    def wrapped_driver(self):
        """Returns the WebDriver instance wrapped by this EventsFiringWebDriver"""
        return self._driver
    
    def get(self, url):
        self._dispatch("navigate_to", (url, self._driver), "get", (url, ))
        
    def back(self):
        self._dispatch("navigate_back", (self._driver,), "back", ())
        
    def forward(self):
        self._dispatch("navigate_forward", (self._driver,), "forward", ())
        
    def execute_script(self, script, *args):
        unwrapped_args = (script,) + self._unwrap_element_args(args)
        return self._dispatch("execute_script", (script, self._driver), "execute_script", unwrapped_args)
    
    def execute_async_script(self, script, *args):
        unwrapped_args = (script,) + self._unwrap_element_args(args)
        return self._dispatch("execute_script", (script, self._driver), "execute_async_script", unwrapped_args)
    
    def close(self):
        self._dispatch("close", (self._driver,), "close", ())
        
    def quit(self):
        self._dispatch("quit", (self._driver,), "quit", ())
        
    def find_element(self, by=By.ID, value=None):
        return self._dispatch("find", (by, value, self._driver), "find_element", (by, value))
    
    def find_elements(self, by=By.ID, value=None):
        return self._dispatch("find", (by, value, self._driver), "find_elements", (by, value))
    
    def find_element_by_id(self, id_):
        return self.find_element(by=By.ID, value=id_)
    
    def find_elements_by_id(self, id_):
        return self.find_elements(by=By.ID, value=id_)
    
    def find_element_by_xpath(self, xpath):
        return self.find_element(by=By.XPATH, value=xpath)
    
    def find_elements_by_xpath(self, xpath):
        return self.find_elements(by=By.XPATH, value=xpath)
    
    def find_element_by_link_text(self, link_text):
        return self.find_element(by=By.LINK_TEXT, value=link_text)
    
    def find_elements_by_link_text(self, text):
        return self.find_elements(by=By.LINK_TEXT, value=text)
    
    def find_element_by_partial_link_text(self, link_text):
        return self.find_element(by=By.PARTIAL_LINK_TEXT, value=link_text)
    
    def find_elements_by_partial_link_text(self, link_text):
        return self.find_elements(by=By.PARTIAL_LINK_TEXT, value=link_text)
    
    def find_element_by_name(self, name):
        return self.find_element(by=By.NAME, value=name)
    
    def find_elements_by_name(self, name):
        return self.find_elements(by=By.NAME, value=name)
    
    def find_element_by_tag_name(self, name):
        return self.find_element(by=By.TAG_NAME, value=name)
    
    def find_elements_by_tag_name(self, name):
        return self.find_elements(by=By.TAG_NAME, value=name)
    
    def find_element_by_class_name(self, name):
        return self.find_element(by=By.CLASS_NAME, value=name)
    
    def find_elements_by_class_name(self, name):
        return self.find_elements(by=By.CLASS_NAME, value=name)
    
    def find_element_by_css_selector(self, css_selector):
        return self.find_element(by=By.CSS_SELECTOR, value=css_selector)
    
    def find_elements_by_css_selector(self, css_selector):
        return self.find_elements(by=By.CSS_SELECTOR, value=css_selector)
    
    def _dispatch(self, l_call, l_args, d_call, d_args):
        getattr(self._listener, "before_%s" % l_call)(*l_args)
        try:
            result = getattr(self._driver, d_call)(*d_args)
        except Exception, e:
            self._listener.on_exception(e, self._driver)
            raise e
        getattr(self._listener, "after_%s" % l_call)(*l_args)
        return  _wrap_elements(result, self)
    
    def _unwrap_element_args(self, args):
        if isinstance(args, EventFiringWebElement):
            return args.wrapped_element
        elif isinstance(args, tuple):
            return tuple([self._unwrap_element_args(item) for item in args])
        elif isinstance(args, list):
            return [self._unwrap_element_args(item) for item in args]
        else:
            return args
        
    def __setattr__(self, item, value):
        if item.startswith("_") or not hasattr(self._driver, item):
            object.__setattr__(self, item, value)
        else:
            try:
                object.__setattr__(self._driver, item, value)
            except Exception, e:
                self._listener.on_exception(e, self._driver)
                raise e
            
    def __getattr__(self, name):
        
        def _wrap(*args):
            try:
                result = attrib(*args)
                return _wrap_elements(result, self)
            except Exception, e:
                self._listener.on_exception(e, self._driver)
                raise e
                
        if hasattr(self._driver, name):
            try:
                attrib = getattr(self._driver, name)
                if not callable(attrib):
                    return attrib
            except Exception, e:
                self._listener.on_exception(e, self._driver)
                raise e
            return _wrap
        
        raise AttributeError(name)
    
    
class EventFiringWebElement(object):
    """"
    A wrapper around WebElement instance which supports firing events
    """
    
    def __init__(self, webelement, ef_driver):
        """
        Creates a new instance of the EventFiringWebElement
        """
        self._webelement = webelement
        self._ef_driver = ef_driver
        self._driver = ef_driver.wrapped_driver
        self._listener = ef_driver._listener
        
    @property
    def wrapped_element(self):
        """Returns the WebElement wrapped by this EventFiringWebElement instance"""
        return self._webelement
    
    def click(self):
        self._dispatch("click", (self._webelement, self._driver), "click", ())
        
    def clear(self):
        self._dispatch("change_value_of", (self._webelement, self._driver), "clear", ())
        
    def send_keys(self, *value):
        self._dispatch("change_value_of", (self._webelement, self._driver), "send_keys", value)
        
    def find_element(self, by=By.ID, value=None):
        return self._dispatch("find", (by, value, self._driver), "find_element", (by, value))
    
    def find_elements(self, by=By.ID, value=None):
        return self._dispatch("find", (by, value, self._driver), "find_elements", (by, value))
    
    def find_element_by_id(self, id_):
        return self.find_element(by=By.ID, value=id_)
    
    def find_elements_by_id(self, id_):
        return self.find_elements(by=By.ID, value=id_)
    
    def find_element_by_name(self, name):
        return self.find_element(by=By.NAME, value=name)
    
    def find_elements_by_name(self, name):
        return self.find_elements(by=By.NAME, value=name)
    
    def find_element_by_link_text(self, link_text):
        return self.find_element(by=By.LINK_TEXT, value=link_text)
    
    def find_elements_by_link_text(self, link_text):
        return self.find_elements(by=By.LINK_TEXT, value=link_text)
    
    def find_element_by_partial_link_text(self, link_text):
        return self.find_element(by=By.PARTIAL_LINK_TEXT, value=link_text)
    
    def find_elements_by_partial_link_text(self, link_text):
        return self.find_elements(by=By.PARTIAL_LINK_TEXT, value=link_text)
    
    def find_element_by_tag_name(self, name):
        return self.find_element(by=By.TAG_NAME, value=name)
    
    def find_elements_by_tag_name(self, name):
        return self.find_elements(by=By.TAG_NAME, value=name)
    
    def find_element_by_xpath(self, xpath):
        return self.find_element(by=By.XPATH, value=xpath)
    
    def find_elements_by_xpath(self, xpath):
        return self.find_elements(by=By.XPATH, value=xpath)
    
    def find_element_by_class_name(self, name):
        return self.find_element(by=By.CLASS_NAME, value=name)
    
    def find_elements_by_class_name(self, name):
        return self.find_elements(by=By.CLASS_NAME, value=name)
    
    def find_element_by_css_selector(self, css_selector):
        return self.find_element(by=By.CSS_SELECTOR, value=css_selector)
    
    def find_elements_by_css_selector(self, css_selector):
        return self.find_elements(by=By.CSS_SELECTOR, value=css_selector)
    
    def _dispatch(self, l_call, l_args, d_call, d_args):
        getattr(self._listener, "before_%s" % l_call)(*l_args)
        try:
            result = getattr(self._webelement, d_call)(*d_args)
        except Exception, e:
            self._listener.on_exception(e, self._driver)
            raise e
        getattr(self._listener, "after_%s" % l_call)(*l_args)
        return  _wrap_elements(result, self._ef_driver)
    
    def __setattr__(self, item, value):
        if item.startswith("_") or not hasattr(self._webelement, item):
            object.__setattr__(self, item, value)
        else:
            try:
                object.__setattr__(self._webelement, item, value)
            except Exception, e:
                self._listener.on_exception(e, self._driver)
                raise e
            
    def __getattr__(self, name):
        
        def _wrap(*args):
                try:
                    result = attrib(*args)
                    return _wrap_elements(result, self._ef_driver)
                except Exception, e:
                    self._listener.on_exception(e, self._driver)
                    raise e
                
        if hasattr(self._webelement, name):
            try:
                attrib = getattr(self._webelement, name)
                if not callable(attrib):
                    return attrib
            except Exception, e:
                self._listener.on_exception(e, self._driver)
                raise e
            return _wrap
        
        raise AttributeError(name)
