import cassandra
import cassandra.cluster
import random
import os
import pkg_resources
import datetime
from websucker.parser import normalize_link,urlunparse

VERSION = "sucker6"


def get_schema():
    with pkg_resources.resource_stream(__name__,"schema.sql") as f:
        schema = f.read()
        return str(schema,encoding="utf8")

class Data:
    """
    Database of text documents
    """
    def __init__(self,keyspace="websucker",cassandra_host="127.0.0.1",cassandra_port=9042):
        # execution profile
        ep = cassandra.cluster.ExecutionProfile(request_timeout=240.0)
        profiles = {cassandra.cluster.EXEC_PROFILE_DEFAULT:ep}
        self.cluster = cassandra.cluster.Cluster([cassandra_host],port=cassandra_port,execution_profiles=profiles)
        self.session = self.cluster.connect(keyspace)

        self.check_document_select_query = self.session.prepare("SELECT count(url_hash) FROM paragraph_checksums WHERE checksum=?" )



        self.index_response_link_update = self.session.prepare("""
        UPDATE links SET 
        link_status ='redirect',
        redirect_target = ?,
        update_time = toTimestamp(now())
        WHERE
        domain_name=? AND
        url_path=? AND
        url_query=? 
        """)

        self.domain_quality_update = self.session.prepare("""
        UPDATE domain_quality SET 
            seen_count=?,
            good_size=?,
            good_count=?,
            good_probability=?,
            good_originality=?,
            average_good_characters=?,
            content_size=?,
            content_count=?,
            content_probability=?,
            content_originality=?,
            average_content_characters=?,
            fetched_count=?,
            average_fetched_good_characters=?,
            gain_ratio=?,
            update_time = toTimestamp(now())
        WHERE
            domain_name=? AND
            day=toDate(now())
        """)

        self.index_response_insert_html = self.session.prepare("""
INSERT INTO html(
  day,
  domain_name,
  source_link,
  target_link,
  redirect_links,
  status,
  headers,
  content,
  agent_version,
  update_time
  ) VALUES (toDate(now()),?,?,?,?,?,?,?,?,toTimestamp(now()));
""")

        self.index_content_link_insert = self.session.prepare("""
INSERT INTO links (
url_schema,
domain_name,
url_path,
url_query,
link_status,
update_time
) VALUES (?,?,?,?,'seen',?) IF NOT EXISTS
""")

        self.daily_links_insert = self.session.prepare("""
INSERT INTO daily_links (
day,
domain_name,
url_path,
url_query,
link_status,
body_size,
link_originality,
update_time
) VALUES (toDate(now()),?,?,?,?,?,?,toTimestamp(now()))
""")
        self.daily_links_select = self.session.prepare("""
SELECT 
domain_name,
link_status,
count(link_status) 
FROM daily_links WHERE day=toDate(now()) GROUP BY domain_name,link_status
""")
        # PArsed Content
        self.index_content_content_insert = self.session.prepare("""
INSERT INTO content(
  domain_name,
  target_link,
  links,
  title,
  description,
  section,
  authors,
  tags,
  article_published_time,
  text_date,
  body,
  body_size,
  agent_version,
  update_time
  ) VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?);
""")

        self.paragraph_checksums_insert = self.session.prepare("INSERT INTO paragraph_checksums (checksum,url_hash) VALUES(?,?)")
        self.index_content_links_update = self.session.prepare("UPDATE links SET link_status=?, link_originality=?,body_size=?,url_schema=? WHERE domain_name=? AND url_path = ? AND url_query=? ")
        self.check_domain_count = self.session.prepare("select count(url_path) from links where domain_name=? and link_status = ?")

        self.check_domain_size = self.session.prepare("select sum(body_size),sum(link_originality) from links where domain_name=? and link_status =?")

        self.domains_select = self.session.prepare("SELECT domain_name,seen_count,fetched_count,gain_ratio,average_fetched_good_characters FROM domain_quality PER PARTITION LIMIT 1")


    def index_responses(self,source_link,responses):
        # Redirect links
        pl = normalize_link(source_link)
        for response in responses:
            tl = response.get_canonical()
            r = (
                tl,
                pl[1],
                pl[2],
                pl[3],
            )
            if pl != tl:
                res = self.session.execute(self.index_response_link_update,r)
            d = (
                pl[1],
                source_link,
                response.get_canonical(),
                response.redirects,
                response.status,
                response.headers,
                response.get_content(),
                VERSION,
            )
            self.session.execute(self.index_response_insert_html,d)
    
    def daily_report(self):
        rows = self.session.execute(self.daily_links_select)
        for row in rows:
            print(row[0],row[1],row[2])

    def index_follow_links(self,parser,links,connection):
        # Index seen links

        follow_links = set()
        for l in links:
            if parser.is_link_good(l):
                #if connection is not None and parser.listen_robot and not connection.is_robot_good(l):
                #    continue
                link = normalize_link(l,strip_query=parser.strip_query)
                follow_links.add(urlunparse(link))

        newlinkdomains = set()
        for link in follow_links:
            value = []
            nl = normalize_link(link)
            value +=  nl
            value.append(datetime.date.today())
            rows = self.session.execute(self.index_content_link_insert,value)
            row = rows.one()
            if row.applied:
                newlinkdomains.add(nl[1])
        for domain in newlinkdomains:
            self.check_domain(domain)


    def index_content(self,target_link,parsed_document):
        nl = normalize_link(target_link)
        domain_name = nl[1]
        assert len(domain_name) > 1

        pd = parsed_document
        body_length = 0
        if pd.body is not None:
            body_length = len(pd.body)
        value = ( 
          domain_name,
          target_link,
          pd.get_links(),
          pd.title,
          pd.description,
          pd.section,
          pd.authors,
          pd.tags,
          pd.article_published_time,
          pd.text_date,
          pd.body,
          body_length,
            VERSION,
          pd.current_time
        )
        content_future = self.session.execute_async(self.index_content_content_insert,value)
        # result later

        link_status = "good"
        originality = 0
        tsz = 0
        if pd.body is None:
            link_status = "bad_parse"
        else:
            tsz = len(pd.body)
            if tsz < 300:
                link_status = "bad_small"

        if link_status == "good":

            futures = []
            for pc,psz in zip(pd.paragraph_checksums,pd.paragraph_sizes):
                fut = self.session.execute_async(self.paragraph_checksums_insert,(pc,hash(nl[1] + "/" + nl[2] + "?" + nl[3])))
                futures.append(fut)
            for fut in futures:
                fut.result()
            originality = self.check_document(pd.paragraph_checksums,pd.paragraph_sizes)
            if originality < 0.8:
                link_status = "bad_copy"
        print(nl)
        self.session.execute(self.index_content_links_update,(link_status,originality,tsz,nl[0],nl[1],nl[2],nl[3]))
        content_future.result()
        print("<<<< " + link_status + " " + str(originality))
        dl = (
            nl[1],
            nl[2],
            nl[3],
            link_status,
            tsz,
            originality
        )
        self.session.execute(self.daily_links_insert,dl)

    def check_document(self,paragraph_checksums,paragraph_sizes):
       tsz = sum(paragraph_sizes)
       if tsz == 0:
           return 0
       copies = 0
       futures = []
       for pc,psz in zip(paragraph_checksums,paragraph_sizes):
           futures.append(self.session.execute_async(self.check_document_select_query,(pc,)))

       for fut,psz in zip(futures,paragraph_sizes):
           rows = fut.result()
           res = rows.one()[0]
           if res > 1:
               copies += psz
       return (tsz-copies)/tsz


    def check_domain(self, domain):
        assert len(domain) > 0
        seen_count = None
        good_size = None
        good_count = None
        good_probability = None
        good_originality = None
        average_good_characters = None
        content_size = None
        content_count = None
        content_probability = None
        content_originality = None
        average_content_characters = None
        fetched_count = None
        average_fetched_good_characters = None
        gain_ratio = None

        counts = {
            "good":0,
            "bad_copy":0,
            "bad_small":0,
            "bad_httpcode":0,
            "bad_type":0,
            "bad_content":0,
            "bad_parse":0,
            "seen":0
        }
        for k in counts.keys():
            res = self.session.execute(self.check_domain_count,(domain,k))
            co = res.one()[0]
            counts[k]= co

        seen_count = counts["seen"]
        good_count = counts["good"]
        content_count = counts["good"] + counts["bad_copy"] + counts["bad_small"]

        fetched_count = sum(counts.values()) - counts["seen"]

        if fetched_count > 0:
            content_probability = content_count / fetched_count
            good_probability = good_count / fetched_count
            sizes = {
                "good":0,
                "bad_copy":0,
                "bad_small":0
            }

            originalities ={}

            for k in sizes.keys():
                res = self.session.execute(self.check_domain_size,(domain,k))
                row = res.one()
                co =row[0]
                originalities[k] = row[1]
                sizes[k]= co
            good_size = sizes["good"]
            content_size = sum(sizes.values())
            if good_count > 0:
                good_originality = originalities["good"] / good_count
            if content_count > 0:
                content_originality =  sum(originalities.values()) / content_count
        
        if good_count > 0:
            average_good_characters = good_size / good_count  * good_originality
            average_fetched_good_characters = good_size * good_originality / fetched_count

            gain_ratio = average_fetched_good_characters / fetched_count

        if content_count > 0:
            average_content_characters = content_size / content_count

        #print(sizes)
        #print(originalities)
        uv = (
        seen_count,
        good_size,
        good_count,
        good_probability,
        good_originality,
        average_good_characters,
        content_size,
        content_count,
        content_probability,
        content_originality,
        average_content_characters,
        fetched_count,
        average_fetched_good_characters,
        gain_ratio,
        domain)
        if fetched_count > 0 or seen_count > 0:
            self.session.execute(self.domain_quality_update,uv)
        return average_fetched_good_characters

    def all_domains(self,count):
        rows = self.session.execute(self.domains_select)
        domains = []
        for row in rows:
            domain = row[0]
            seen_count = row[1]
            fetched_count = row[2]
            gain_ratio = row[3]
            afg = row[4]
            if fetched_count and afg and seen_count:
                domains.append(tuple(row))
        l = len(domains)
        ss = min(l,count)
        res = []
        if ss > 0:
            # sort according to ratio
            res = list(sorted(domains,key=lambda x:x[4],reverse=True))[0:ss]
        # returns sorted list of tuples domain,gain_ratio
        return res

    def get_best_domains(self,count):
        # get all domains
        rows = self.session.execute(self.domains_select)
        domains = []
        for row in rows:
            domain = row[0]
            seen_count = row[1]
            fetched_count = row[2]
            gain_ratio = row[3]
            afg = row[4]
            if seen_count and fetched_count and gain_ratio:
                domains.append((domain,gain_ratio))
        l = len(domains)
        ss = min(l,count)
        res = []
        if ss > 0:
            # sort according to ratio
            res = list(sorted(domains,key=lambda x:x[1],reverse=True))[0:ss]
        # returns sorted list of tuples domain,gain_ratio
        return res

    def get_unvisited_domains(self,count):
        # get all domains
        rows = self.session.execute(self.domains_select)
        domains = []
        for row in rows:
            domain = row[0]
            seen_count = row[1]
            fetched_count = row[2]
            gain_ratio = row[3]
            afg = row[4]
            if seen_count and not fetched_count:
                domains.append(domain)
        ss = min(len(domains),count)
        return random.sample(domains,ss)
    
    def get_visit_links(self,domain,recent_count,old_count,random_count):
        dblinks = []
        rows = self.session.execute("SELECT url_schema,url_path,url_query,update_time FROM links Where domain_name=%s AND link_status='seen'",(domain,))
        for row in rows:
            link = urlunparse((row[0],domain,row[1],row[2]))
            dblinks.append((link,row[3]))

        visitlinks = []
        dblinks.sort(key=lambda x:x[1])
        random_links = []
        for i,(link,time) in enumerate(dblinks):
            #print(link,time)
            if i < recent_count:
                visitlinks.append(link)
            elif i >= len(dblinks) - old_count:
                visitlinks.append(link)
            else:
                random_links.append(link)
        sc = min(random_count,len(random_links))
        if sc > 0:
            visitlinks += random.sample(random_links,sc)
        return visitlinks