#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License,
    or (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
    See the GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, see <http://www.gnu.org/licenses/>.
    
    @author: spoob
    @author: RaNaN
    @author: mkaay
    @author: jeix
    @version: v0.4.0
"""

import time
from os import rename
from os.path import exists
from cStringIO import StringIO
import pycurl

class AbortDownload(Exception):
    pass

class FtpRequest:
    def __init__(self, interface=None):

        self.dl_time = 0
        self.dl_finished = 0
        self.dl_size = 0
        self.dl_arrived = 0
        self.dl = False

        self.abort = False

        self.timeout = 5
        self.auth = False
        
        bufferBase = 1024
        bufferMulti = 4
        self.bufferSize = bufferBase*bufferMulti
        self.canContinue = False
        self.offset = 0
        
        self.dl_speed = 0.0
        self.averageSpeed = 0.0
        self.averageSpeeds = []
        self.averageSpeedTime = 0.0
        self.averageSpeedCount = 0.0
        
        self.speedLimitActive = False
        self.maxSpeed = 0
        self.isSlow = False
        self.interface = interface
        
        # change this for connection information
        self.debug = False

        self.init_curl()

    def set_timeout(self, timeout):
        self.timeout = int(timeout)

    def init_curl(self):
        self.rep = StringIO()
        self.header = ""

        self.pycurl = pycurl.Curl()
        self.pycurl.setopt(pycurl.FOLLOWLOCATION, 1)
        self.pycurl.setopt(pycurl.MAXREDIRS, 5)
        self.pycurl.setopt(pycurl.TIMEOUT, (self.timeout*3600))
        self.pycurl.setopt(pycurl.CONNECTTIMEOUT, 30)
        self.pycurl.setopt(pycurl.NOSIGNAL, 1)
        self.pycurl.setopt(pycurl.NOPROGRESS, 0)
        self.pycurl.setopt(pycurl.PROGRESSFUNCTION, self.progress)
        self.pycurl.setopt(pycurl.AUTOREFERER, 1)
        self.pycurl.setopt(pycurl.BUFFERSIZE, self.bufferSize)
        self.pycurl.setopt(pycurl.SSL_VERIFYPEER, 0)
        if self.debug:
            self.pycurl.setopt(pycurl.VERBOSE, 1)
        if self.interface:
            self.pycurl.setopt(pycurl.INTERFACE, self.interface)
    
  
    def add_auth(self, user, pw):        
        self.auth = True
        self.pycurl.setopt(pycurl.USERNAME, user)
        self.pycurl.setopt(pycurl.PASSWORD, pw)

    def add_proxy(self, protocol, adress):
        # @TODO: pycurl proxy protocoll selection
        self.pycurl.setopt(pycurl.PROXY, adress.split(":")[0])
        self.pycurl.setopt(pycurl.PROXYPORT, adress.split(":")[1])

    def download(self, url, file_name):
        file_temp = self.get_free_name(file_name) + ".part"
        self.fp = open(file_temp, 'wb')

        self.init_curl()
        self.pycurl.setopt(pycurl.URL, url)
                    
        self.dl_arrived = self.offset       
        
        if self.auth:
            self.add_auth(self.user, self.pw)

        self.dl_time = time.time()
        self.dl = True
        
        self.chunkSize = 0
        self.chunkRead = 0
        self.subStartTime = 0
        self.maxChunkSize = 0
        
        def restLimit():
            subTime = time.time() - self.subStartTime
            if subTime <= 1:
                if self.speedLimitActive:
                    return self.maxChunkSize
                else:
                    return -1
            else:
                self.updateCurrentSpeed(float(self.chunkRead/1024) / subTime)
                
                self.subStartTime = time.time()
                self.chunkRead = 0
                if self.maxSpeed > 0:
                    self.maxChunkSize = self.maxSpeed
                else:
                    self.maxChunkSize = 0
                return 0

        def writefunc(buf):
            if self.abort:
                return False
            chunkSize = len(buf)
            while chunkSize > restLimit() > -1:
                time.sleep(0.05)
            self.maxChunkSize -= chunkSize
            self.fp.write(buf)
            self.chunkRead += chunkSize
            self.dl_arrived += chunkSize
            
        self.pycurl.setopt(pycurl.WRITEFUNCTION, writefunc)
        
        try:
            self.pycurl.perform()
        except Exception, e:
            code, msg = e
            if not code == 23:
                raise Exception, e
                
        self.fp.close()
        
        if self.abort:
            raise AbortDownload

        free_name = self.get_free_name(file_name)
        rename(file_temp, free_name)
        
        self.dl = False
        self.dl_finished = time.time()

        return free_name
    
    def updateCurrentSpeed(self, speed):
        self.dl_speed = speed
        if self.averageSpeedTime + 10 < time.time():
            self.averageSpeeds = []
            self.averageSpeeds.append(self.averageSpeed)
            self.averageSpeeds.append(speed)
            self.averageSpeed = (speed + self.averageSpeed)/2
            self.averageSpeedTime = time.time()
            self.averageSpeedCount = 2
        else:
            self.averageSpeeds.append(speed)
            self.averageSpeedCount += 1
            allspeed = 0.0
            for s in self.averageSpeeds:
                allspeed += s
            self.averageSpeed = allspeed / self.averageSpeedCount
    
    def write_header(self, string):
        self.header += string

    def get_rep(self):
        value = self.rep.getvalue()
        self.rep.close()
        self.rep = StringIO()
        return value
    
    def get_header(self):
        h = self.header
        self.header = ""
        return h

    def get_speed(self):
        try:
            return self.dl_speed
        except:
            return 0

    def get_ETA(self):
        try:
            return (self.dl_size - self.dl_arrived) / (self.dl_arrived / (time.time() - self.dl_time))
        except:
            return 0

    def kB_left(self):
        return (self.dl_size - self.dl_arrived) / 1024
    
    def progress(self, dl_t, dl_d, up_t, up_d):
        if self.abort:
            return False
        self.dl_arrived = int(dl_d)
        self.dl_size = int(dl_t)

    def get_free_name(self, file_name):
        file_count = 0
        while exists(file_name):
            file_count += 1
            if "." in file_name:
                file_split = file_name.split(".")
                temp_name = "%s-%i.%s" % (".".join(file_split[:-1]), file_count, file_split[-1])
            else:
                temp_name = "%s-%i" % (file_name, file_count)
            if not exists(temp_name):
                file_name = temp_name
        return file_name
    
    def __del__(self):
        self.clean()
    
    def clean(self):
        try:
            self.pycurl.close()
        except:
            pass

# def getURL(url):
    # """
        # currently used for update check
    # """
    # req = Request()
    # c = req.load(url)
    # req.pycurl.close()
    # return c

if __name__ == "__main__":
    import doctest
    doctest.testmod()