import os
import sys
import time
import json

from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.chrome.options import Options
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
from selenium.webdriver.common.keys import Keys
from selenium.webdriver.common.action_chains import ActionChains
import selenium.common.exceptions
from Facebook.facebook_parser import FacebookParser

from crawler import Crawler


class FacebookCrawler(Crawler, FacebookParser):


    def __init__(self, base_url: str, file_name: str):
        super().__init__(base_url, file_name)

        try:
            with open(os.path.join('locators.json')) as file:
                self.locators = json.load(file)

            with open(os.path.join('Facebook', 'inputs', self.filename)) as file:
                self.URLS = tuple(file.readlines())
        except FileNotFoundError:
            print(os.path.join('Facebook', 'inputs', self.filename))
            print("Invalid input value")
            sys.exit(1)

    # crawling part of the code 
    def crawl(self):
        counter = len(self.URLS)
        for idx,url in enumerate(self.URLS):
            # redirect and wait for page to load
            self.driver.get(url)
            self.driver.implicitly_wait(4)

            if 'videos' in url:
                try:
                    self.driver.find_element(By.XPATH, "//*[text()='Most relevant' or text()='Newest' or text()='Oldest']")
                except selenium.common.exceptions.NoSuchElementException:
                    self.driver.find_element(By.XPATH, "//span[contains(@class, 'x6ikm8r x10wlt62 xlyipyv')]").click()
                    if self.driver.find_element(By.XPATH, "//div[contains(@class, 'x78zum5 xdt5ytf x1iyjqo2 x7ywyr2')]") is not None:
                        print('Cant crawl comments section')
                        continue
                
                self.close_censorship('Newest')
            else:
                try:
                    self.driver.find_element(By.XPATH, "//*[text()='Most relevant' or text()='Newest' or text()='Oldest']")
                except:
                    pass

                self.close_censorship('All comments')

            self.driver.implicitly_wait(3)
            print('continue scraping')

            # clicking features
            self.view_more_comments()
            self.show_replies()
            self.click_see_more()
            
            # # parsing part of the code

            # Dictionary of classes, if facebook changes any class, rewrite this DICT
            if '/videos/' in url:
                self.class_dict = self.locators['facebook_video_locators']
            elif '/posts/' in url:
                self.class_dict = self.locators['facebook_post_locators']

            self.parse(self.driver.page_source, self.class_dict, self.filename)
            print(f'Done: [{idx + 1}/{counter}]')

    def view_more_comments(self):
        elements = self.driver.find_elements(By.XPATH, "//span[contains(text(), 'comments') and contains(text(), 'View') and contains(text(), 'more')]")
        while elements:
            try:
                self.driver.execute_script("arguments[0].click();", elements[0])
                elements = self.driver.find_elements(By.XPATH, "//span[contains(text(), 'comments') and contains(text(), 'View') and contains(text(), 'more')]")
                self.driver.execute_script("var scrollingElement = (document.scrollingElement || document.body);scrollingElement.scrollTop = scrollingElement.scrollHeight;")
            except selenium.common.exceptions.StaleElementReferenceException:
                elements = self.driver.find_elements(By.XPATH, "//span[contains(text(), 'comments') and contains(text(), 'View') and contains(text(), 'more')]")

 
    # function, for showing hidden replies
    def show_replies(self):

        repl_elements = self.driver.find_elements(By.XPATH, "//span[contains(text(), 'repl') and not(contains(text(), 'Hide')) and not(contains(text(), 'Newest'))]")
        i = 1
        while repl_elements:
            
            try:
                for element in repl_elements:
                    self.driver.execute_script("arguments[0].click();", element)
                    time.sleep(0.5)

            except selenium.common.exceptions.StaleElementReferenceException:
                pass
            repl_elements = self.driver.find_elements(By.XPATH, "//span[contains(text(), 'repl') and not(contains(text(), 'Hide')) and not(contains(text(), 'Newest'))]")

    # method for expanding comments
    def click_see_more(self):

        elements = self.driver.find_elements(By.XPATH, "//*[text()='See more']")

        for element in elements:   
            self.driver.execute_script("arguments[0].click();", element)
            


    # method for clossing most relevant filter to Newest
    def close_censorship(self, classification: str):
        self.driver.implicitly_wait(3)
        try:
            dropdown = self.driver.find_element(By.XPATH, "//*[text()='Most relevant' or text()='Newest']")
            self.driver.execute_script("arguments[0].click();", dropdown) # clicking on it
            
            newest_comments = self.driver.find_element(By.XPATH, f"//*[text()='{classification}']")
            self.driver.execute_script("arguments[0].click();", newest_comments) # clicking on it
        except:
            self.close_censorship(classification)

   
    def close(self):
        print('Scraping ended succesffuly')
        self.driver.quit()
        sys.exit(0)