from urllib.request import urlopen, Request
from googleapiclient.discovery import build
import requests
import httpx
import re
from bs4 import BeautifulSoup
import re, math
from collections import Counter
import numpy as np
import asyncio
import nltk
from sentence_transformers import SentenceTransformer, util

nltk.download('punkt')

WORD = re.compile(r"\w+")
model = SentenceTransformer('sentence-transformers/all-MiniLM-L6-v2')


# returns cosine similarity of two vectors
# input: two vectors
# output: integer between 0 and 1.
def get_cosine(vec1, vec2):
    intersection = set(vec1.keys()) & set(vec2.keys())

    # calculating numerator
    numerator = sum([vec1[x] * vec2[x] for x in intersection])

    # calculating denominator
    sum1 = sum([vec1[x] ** 2 for x in vec1.keys()])
    sum2 = sum([vec2[x] ** 2 for x in vec2.keys()])
    denominator = math.sqrt(sum1) * math.sqrt(sum2)

    # checking for divide by zero
    if denominator == 0:
        return 0.0
    else:
        return float(numerator) / denominator


# converts given text into a vector
def text_to_vector(text):
    # uses the Regular expression above and gets all words
    words = WORD.findall(text)
    # returns a counter of all the words (count of number of occurences)
    return Counter(words)


# returns cosine similarity of two words
# uses: text_to_vector(text) and get_cosine(v1,v2)
def cosineSim(text1, text2):
    vector1 = text_to_vector(text1)
    vector2 = text_to_vector(text2)
    # print vector1,vector2
    cosine = get_cosine(vector1, vector2)
    return cosine

def sentence_similarity(text1, text2):
    embedding_1= model.encode(text1, convert_to_tensor=True)
    embedding_2 = model.encode(text2, convert_to_tensor=True)

    o = util.pytorch_cos_sim(embedding_1, embedding_2)
    return round(o.item(), 2)

def get_soup_requests(url):
    page = requests.get(url)
    if page.status_code == 200:
        soup = BeautifulSoup(page.content, "html.parser")
        return soup
    print("HTML soup failed")
    return None


def get_soup_httpx(url):
    client = httpx.Client(timeout=30)
    try:
        page = client.get(url)
        if page.status_code == httpx.codes.OK:
            soup = BeautifulSoup(page.content, "html.parser")
            return soup
    except:
        print("HTTPx soup failed")
        return None

def getSentences(text):
    from nltk.tokenize import sent_tokenize

    sents = sent_tokenize(text)
    two_sents = []
    for i in range(len(sents)):
        if (i % 2) == 0:
            two_sents.append(sents[i])
        else:
            two_sents[len(two_sents) - 1] += " " + sents[i]
    return two_sents


def googleSearch(
    plag_option,
    sentences,
    urlCount,
    scoreArray,
    urlList,
    sorted_date,
    domains_to_skip,
    api_key,
    cse_id,
    **kwargs,
):
    service = build("customsearch", "v1", developerKey=api_key)
    for i, sentence in enumerate(sentences):
        results = (
            service.cse()
            .list(q=sentence, cx=cse_id, sort=sorted_date, **kwargs)
            .execute()
        )
        if "items" in results and len(results["items"]) > 0:
            for count, link in enumerate(results["items"]):
                # stop after 5 pages
                if count > 4:
                    break
                # skip user selected domains
                if any(
                    ("." + domain) in link["link"]
                    for domain in domains_to_skip
                ):
                    continue
                # clean up snippet of '...'
                snippet = link["snippet"]
                ind = snippet.find("...")
                if ind < 20 and ind > 9:
                    snippet = snippet[ind + len("... ") :]
                ind = snippet.find("...")
                if ind > len(snippet) - 5:
                    snippet = snippet[:ind]

                # update cosine similarity between snippet and given text
                url = link["link"]
                if url not in urlList:
                    urlList.append(url)
                    scoreArray.append([0] * len(sentences))
                urlCount[url] = urlCount[url] + 1 if url in urlCount else 1
                if plag_option == 'Standard':
                    scoreArray[urlList.index(url)][i] = cosineSim(
                        sentence, snippet)
                else :     
                    scoreArray[urlList.index(url)][i] = sentence_similarity(
                        sentence, snippet
                )
        else:
            print("Google Search failed")
    return urlCount, scoreArray


def getQueries(text, n):
    # return n-grams of size n
    finalq = []
    words = text.split()
    l = len(words)

    for i in range(0, l - n + 1):
        finalq.append(words[i : i + n])

    return finalq


def print2D(array):
    print(np.array(array))


def removePunc(text):
    res = re.sub(r"[^\w\s]", "", text)
    return res


async def get_url_data(url, client):
    try:
        r = await client.get(url)
        # print(r.status_code)
        if r.status_code == 200:
            # print("in")
            soup = BeautifulSoup(r.content, "html.parser")
            return soup
    except Exception:
        print("HTTPx parallel soup failed")
        return None


async def parallel_scrap(urls):
    async with httpx.AsyncClient(timeout=30) as client:
        tasks = []
        for url in urls:
            tasks.append(get_url_data(url=url, client=client))
        results = await asyncio.gather(*tasks, return_exceptions=True)
    return results


def matchingScore(sentence, content):
    if sentence in content:
        return 1
    sentence = removePunc(sentence)
    content = removePunc(content)
    if sentence in content:
        return 1
    else:
        n = 5
        ngrams = getQueries(sentence, n)
        if len(ngrams) == 0:
            return 0
        matched = [x for x in ngrams if " ".join(x) in content]
        return len(matched) / len(ngrams)


async def matchingScoreAsync(sentences, content, content_idx, ScoreArray):
    content = removePunc(content)
    for j, sentence in enumerate(sentences):
        sentence = removePunc(sentence)
        if sentence in content:
            ScoreArray[content_idx][j] = 1
        else:
            n = 5
            ngrams = getQueries(sentence, n)
            if len(ngrams) == 0:
                return 0
            matched = [x for x in ngrams if " ".join(x) in content]
            ScoreArray[content_idx][j] = len(matched) / len(ngrams)
    print(
        f"Analyzed {content_idx+1} of soups (SOUP SUCCEEDED)........................"
    )
    return ScoreArray


async def parallel_analyze(soups, sentences, ScoreArray):
    tasks = []
    for i, soup in enumerate(soups):
        if soup:
            page_content = soup.text
            tasks.append(
                matchingScoreAsync(sentences, page_content, i, ScoreArray)
            )
        else:
            print(
                f"Analyzed {i+1} of soups (SOUP FAILED)........................"
            )
    ScoreArray = await asyncio.gather(*tasks, return_exceptions=True)
    return ScoreArray


async def parallel_analyze_2(soups, sentences, ScoreArray):
    tasks = [[0] * len(ScoreArray[0]) for i in range(len(ScoreArray))]
    for i, soup in enumerate(soups):
        if soup:
            page_content = soup.text
            for j, sent in enumerate(sentences):
                print(
                    f"Analyzing {i+1} of {len(soups)} soups with {j+1} of {len(sentences)} sentences........................"
                )
                tasks[i][j] = matchingScore(sent, page_content)
        else:
            print(
                f"Analyzed {i+1} of soups (SOUP FAILED)........................"
            )
    ScoreArray = await asyncio.gather(*tasks, return_exceptions=True)
    return ScoreArray