#! /usr/bin/env python

import os, re, sys, glob

bike_state_size = 39
magic_number = "MX05"

class arginfo:
	def __init__(self):
		self.sync = False
		self.filenames = []
		self.start = 0
		self.end = 2000000000
		if sys.platform == "win32":
			self.glob = True
		else:
			self.glob = False

args = arginfo()

class mxheader:
	def __init__(self):
		self.fp = None
		self.nbikes = 0
		self.nbikesout = 0
		self.finishtime = 0
		self.finishlaps = 0
		self.gatetime = 0
		self.track = ""
		self.bikes = []
		self.lastread = ""

def readheader(filename):
	h = mxheader()

	m = re.search(r"((,[0-9]+)+)$", filename)

	filter = []

	if m:
		filename = filename[:m.start()]
		sfilter = m.group(0).split(",")
		for f in sfilter:
			if f:
				filter.append(int(f))

	errstr = "%s is not a valid MX Simulator recording" % filename

	h.fp = file(filename, "rb")

	s = h.fp.readline()
	s = s.split()

	foundheader = None

	if len(s) >= 2 and s[0] == magic_number:
		h.nbikes = int(s[1])
		if h.nbikes > 0:
			foundheader = 1

		if len(s) >= 3:
			h.finishtime = int(s[2])
		if len(s) >= 4:
			h.finishlaps = int(s[3])
		if len(s) >= 5:
			h.gatetime = int(s[4])

	if not foundheader:
		raise errstr + magic_number

	h.track = h.fp.readline()

	if not filter:
		filter = range(h.nbikes)

	for i in xrange(h.nbikes):
		btype = h.fp.readline()
		bnum = h.fp.readline()
		bfilter = (i in filter)
		h.bikes.append((btype, bnum, bfilter))
		if bfilter:
			h.nbikesout += 1

	return h

def syncgatetime(h, t):
	while t < h.gatetime:
		h.fp.read(bike_state_size * h.nbikes)
		t = t + 1

def writebody(fp, headers):
	more = True
	tm = 0.0
	while more:
		more = False
		for h in headers:
			s = h.fp.read(bike_state_size * h.nbikes)

			if s:
				more = True
			else:
				s = h.lastread

			if tm < args.start or tm > args.end:
				continue

			if s:
				for i in xrange(h.nbikes):
					if h.bikes[i][2]:
						fp.write(s[bike_state_size * i:bike_state_size * (i + 1)])
				h.lastread = s
			else:
				return

		tm = tm + 1.0 / 128.0

def splicedemos(inputs, output):
	headers = []
	for fn in inputs:
		headers.append(readheader(fn))

	fp = file(output, "wb")

	nbikes = 0
	finishtime = 0
	finishlaps = 0
	gatetime = 1000000

	for h in headers:
		nbikes = nbikes + h.nbikesout
		if finishtime < h.finishtime:
			finishtime = h.finishtime
		if finishlaps < h.finishlaps:
			finishlaps = h.finishlaps
		if h.gatetime > 0 and gatetime > h.gatetime:
			gatetime = h.gatetime

	if gatetime == 1000000:
		gatetime = 0

	fp.write("%s %d %d %d %d\n" % (magic_number, nbikes, finishtime, finishlaps, gatetime))
	fp.write(headers[0].track);

	for h in headers:
		for b in h.bikes:
			if b[2]:
				fp.write(b[0])
				fp.write(b[1])

	if args.sync and gatetime > 0:
		for h in headers:
			syncgatetime(h, gatetime)

	writebody(fp, headers)

	fp.close()

	for h in headers:
		h.fp.close()

def parsetime(s):
	s = s.split(":")

	if len(s) == 2:
		return float(s[0]) * 60.0 + float(s[1])

	return float(s[0]) 

def setcut(a):
	m = re.search(r"([0-9.:]+)-([0-9.:]+)", a)

	if not m:
		return False

	args.start = parsetime(m.group(1))
	args.end = parsetime(m.group(2))

	return args.start and args.end

def parseargs(a):
	global bike_state_size, magic_number

	usage = "usage: mxdemosplice.py" + \
	 " [--sync] [--cut <starttime>-<stoptime>] <input files> <output file>"
	if len(a) == 0:
		return usage
	while len(a) > 0:
		s = a.pop(0)
		if s == "--help":
			return usage
		elif s == "--sync":
			args.sync = True
		elif s == "--cut":
			if not setcut(a.pop(0)):
				return "--cut requires a time range (e.g. 1:20.0-1:45.0)"
		elif s == "--v4":
			bike_state_size = 26
			magic_number = "MX04"
		elif s == "--glob":
			args.glob = True
		elif s == "--noglob":
			args.glob = False
		elif s[0] == "-":
			return "invalid option '"  + s + "'"
		elif args.glob:
			g = glob.glob(s)
			if g:
				args.filenames.extend(g)
			else:
				args.filenames.append(s)
		else:
			args.filenames.append(s)
	if len(args.filenames) < 2:
		return "You must give at least an input and output file"
	return

errormsg = parseargs(sys.argv[1:])
if errormsg:
	sys.stderr.write(errormsg + "\n")
	sys.exit(1)

splicedemos(args.filenames[0:-1], args.filenames[-1])