#!/usr/bin/python3 
import threading
from queue import Queue 

from db import db
from source import Source
from linklist import LinkList
from news import News

def parseSource(s):
    num_worker_threads=10
    sel=None
    rss=False
    if "selector" in s:
        sel=s["selector"]
    if "rss" in s:
        rss=bool(s["rss"])
    l=LinkList(s["link"],sel,rss=rss)

    kw=d.get_keywords(s["category"])
    if l is not None:
        print("[Source] %s: %d total articles" % ( s["name"], len(l.links)))
        for a in l.links:
            if not d.article_exists(a):
                q.put(a)
        print("[Source] %s: %d new articles" % ( s["name"], q.qsize()))


    num_worker_threads=min(10,q.qsize())
    if not q.empty():
        threads=[]
        for i in range(num_worker_threads):
            t = threading.Thread(target=news_worker,args=[s["_id"],kw])
            t.daemon=True
            t.start()
            threads.append(t)
    
        print("Waiting for %d queue elements" % q.qsize())
        q.join() #block until all tasks are done
        print("Finished waiting for the queue")

        for i in range(num_worker_threads):
            q.put(None)
        print("Waiting for %d threads" % len(threads))
        for t in threads:
            t.join(10)
    print("[Source] %s => Finished parsing" %s["name"])

def news_worker(source_id,kw):
    tname=threading.current_thread().name
    while True:
        try:
            item = q.get(timeout=5)
        except:
            print("[%s] Empty queue" % tname)
            break
        if item is None:
            print("[%s] Empty queue (none)" % tname)
            q.task_done()
            break

        print("[Thread %s] %s" % (tname,item))
        try:
            n=News(item,source_id,kw)
            print("[Thread %s] Finished" % tname)
            d.insert_article(n.get())
        except:
            print("whut")
        finally:
            q.task_done()

q=Queue()
d=db()
d.purge_error()
for s in d.sources():
    parseSource(s)