#!/usr/bin/env python

from btqueue import *
from btqueueget import do_download
import os, sys, select, time, signal

children = {}
childdata = {}
states = {}
settings = {}
killed = {}

def read_queue():
	fs = os.listdir(queue_dir)
	ms = {}
	for f in fs: ms[f] = os.stat(queue_dir + "/" + f).st_mtime
	def compare(a, b):
		i = cmp(ms[a], ms[b])
		if i != 0: return i
		return cmp(a, b)
	fs.sort(compare)
	return fs

def start_child(file):
	print "starting", file
	(r, w) = os.pipe()
	sys.stdout.flush()
	sys.stderr.flush()
	pid = os.fork()
	if pid == 0:
		for fd in children.keys(): os.close(fd)
		os.close(r)
		do_download(queue_dir + "/" + file, w, settings)
	os.close(w)
	children[r] = (file, pid)
	states[r] = {}
	childdata[r] = ""

def trimfile(name, width):
	name = name.replace(".torrent", "")
	name = name.replace(".rar", "")
	name = name.replace(".avi", "")
	name = name.replace(".ogm", "")
	if len(name) < width:
		return name
	else:
		return ".." + name[-(width - 2):]

def run():
	last_display = 0
	while 1:
		global settings
		settings = read_settings()
		queue = read_queue()

		max_downloads = int(settings["max-downloads"])
		should_run = queue[:max_downloads]
		running = {}
		for fd in children.keys():
			(file, pid) = children[fd]
			if file in should_run:
				running[file] = 1
			else:
				os.kill(pid, signal.SIGINT)
				killed[pid] = 1
		for file in should_run:
			if not running.has_key(file):
				start_child(file)

		now = time.time()
		display_period = int(settings["display-period"])
		if display_period != 0 and (now - last_display) >= display_period:
			last_display = now
			print "\n\n"
			print "currently downloading:"
			print "%6s %-10s %6s %5s %10s %6s %6s %s" % ("pid", "state", "pct", "size", "eta", "up", "down", "file")
			for fd in children:
				(file, pid) = children[fd]
				(state, pct, size, eta, up, down) = ("-", 0, "-", "-", 0, 0)
				if states.has_key(fd):
					s = states[fd]
					if s.has_key("state"): state = s["state"]
					if s.has_key("pct"): pct = float(s["pct"])
					if s.has_key("size"): size = str(long(s["size"]) / (1L << 20))
					if s.has_key("eta"): eta = s["eta"]
					if s.has_key("up"): up = float(s["up"])
					if s.has_key("down"): down = float(s["down"])
				file = trimfile(file, 40)
				print "%6d %-10s %5.1f%% %5s %10s %6.1f %6.1f %s" % (pid, state, pct, size, eta, up, down, file)
			print len(queue), "in queue"
		sys.stdout.flush()

		write_state_to = settings["write-state-to"]
		if write_state_to != "":
			f = open(write_state_to + ".new", "w")
			for fd in children:
				(file, pid) = children[fd]
				state = states.get(fd, {})
				s = " ".join(map(lambda p: p[0] + "=" + p[1], state.items()))
				print >>f, "running %d %s %s" % (pid, file, s)
			f.close()
			os.rename(write_state_to + ".new", write_state_to)

		(rfds, wfds, efds) = select.select(children.keys(), [], [], 2.0)
		for fd in rfds:
			(file, pid) = children[fd]
			data = os.read(fd, 65536)
			if data == "":
				os.waitpid(pid, 0)
				os.close(fd)
				od = failed_dir
				if states[fd].has_key("state"):
					state = states[fd]["state"]
				else:
					state = "unknown"
				if state == "seed":
					od = complete_dir
					print "seed", file
				elif state == "interrupt":
					print "interrupted", file
				else:
					print "failed", file
				del children[fd]
				del states[fd]
				del childdata[fd]
				if state != "seed" and killed.has_key(pid):
					del killed[pid]
					state = "interrupt"
				if state != "interrupt":
					os.rename(queue_dir + "/" + file, od + "/" + file)
			else:
				childdata[fd] += data
				while 1:
					pos = childdata[fd].find("\n")
					if pos == -1: break
					states[fd] = {}
					for i in childdata[fd][:pos].split(" "):
						(k, v) = i.split("=")
						states[fd][k] = v
					childdata[fd] = childdata[fd][pos + 1:]

if __name__ == "__main__":
	try:
		run()
	except KeyboardInterrupt:
		for fd in children:
			(file, pid) = children[fd]
			try:
				os.kill(pid, signal.SIGINT)
			except:
				pass