"""
This module handles detection and clean ejection of removable storage. (Mainly SD cards)
This is OS depended.
	On windows it looks for removable storage drives.
	On MacOS it specificly looks for SD cards.
	On Linux it looks for anything mounted in /media/
"""
__copyright__ = "Copyright (C) 2013 David Braam - Released under terms of the AGPLv3 License"
import platform
import string
import glob
import os
import stat
import time
import subprocess
import threading
try:
	from xml.etree import cElementTree as ElementTree
except:
	from xml.etree import ElementTree

from Cura.util import profile

_removableCacheUpdateThread = None
_removableCache = []

def _parseStupidPListXML(e):
	if e.tag == 'plist':
		return _parseStupidPListXML(list(e)[0])
	if e.tag == 'array':
		ret = []
		for c in list(e):
			ret.append(_parseStupidPListXML(c))
		return ret
	if e.tag == 'dict':
		ret = {}
		key = None
		for c in list(e):
			if c.tag == 'key':
				key = c.text
			elif key is not None:
				ret[key] = _parseStupidPListXML(c)
				key = None
		return ret
	if e.tag == 'true':
		return True
	if e.tag == 'false':
		return False
	return e.text

def _findInTree(t, n):
	ret = []
	if type(t) is dict:
		if '_name' in t and t['_name'] == n:
			ret.append(t)
		for k, v in t.items():
			ret += _findInTree(v, n)
	if type(t) is list:
		for v in t:
			ret += _findInTree(v, n)
	return ret

def getPossibleSDcardDrives():
	global _removableCache, _removableCacheUpdateThread

	if profile.getPreference('auto_detect_sd') == 'False':
		return []

	if _removableCacheUpdateThread is None:
		_removableCacheUpdateThread = threading.Thread(target=_updateCache)
		_removableCacheUpdateThread.daemon = True
		_removableCache = None
		_removableCacheUpdateThread.start()
	while _removableCache is None:
		time.sleep(0.01)
	return _removableCache

def _updateCache():
	global _removableCache

	while True:
		drives = []
		if platform.system() == "Windows":
			from ctypes import windll
			import ctypes
			bitmask = windll.kernel32.GetLogicalDrives()
			for letter in string.uppercase:
				if letter != 'A' and letter != 'B' and bitmask & 1 and windll.kernel32.GetDriveTypeA(letter + ':/') == 2:
					volumeName = ''
					nameBuffer = ctypes.create_unicode_buffer(1024)
					if windll.kernel32.GetVolumeInformationW(ctypes.c_wchar_p(letter + ':/'), nameBuffer, ctypes.sizeof(nameBuffer), None, None, None, None, 0) == 0:
						volumeName = nameBuffer.value
					if volumeName == '':
						volumeName = 'NO NAME'

					freeBytes = ctypes.c_longlong(0)
					if windll.kernel32.GetDiskFreeSpaceExA(letter + ':/', ctypes.byref(freeBytes), None, None) == 0:
						continue
					if freeBytes.value < 1:
						continue
					drives.append(('%s (%s:)' % (volumeName, letter), letter + ':/', volumeName))
				bitmask >>= 1
		elif platform.system() == "Darwin":
			p = subprocess.Popen(['system_profiler', 'SPUSBDataType', '-xml'], stdout=subprocess.PIPE)
			xml = ElementTree.fromstring(p.communicate()[0])
			p.wait()

			xml = _parseStupidPListXML(xml)
			for dev in _findInTree(xml, 'Mass Storage Device'):
				if 'removable_media' in dev and dev['removable_media'] == 'yes' and 'volumes' in dev and len(dev['volumes']) > 0:
					for vol in dev['volumes']:
						if 'mount_point' in vol:
							volume = vol['mount_point']
							drives.append((os.path.basename(volume), volume + '/', os.path.basename(volume)))

			p = subprocess.Popen(['system_profiler', 'SPCardReaderDataType', '-xml'], stdout=subprocess.PIPE)
			xml = ElementTree.fromstring(p.communicate()[0])
			p.wait()

			xml = _parseStupidPListXML(xml)
			for entry in xml:
				if '_items' in entry:
					for item in entry['_items']:
						for dev in item['_items']:
							if 'removable_media' in dev and dev['removable_media'] == 'yes' and 'volumes' in dev and len(dev['volumes']) > 0:
								for vol in dev['volumes']:
									if 'mount_point' in vol:
										volume = vol['mount_point']
										drives.append((os.path.basename(volume), volume + '/', os.path.basename(volume)))
		else:
			for volume in glob.glob('/media/*'):
				if os.path.ismount(volume):
					drives.append((os.path.basename(volume), volume + '/', os.path.basename(volume)))
				elif volume == '/media/'+os.getenv('USER'):
					for volume in glob.glob('/media/'+os.getenv('USER')+'/*'):
						if os.path.ismount(volume):
							drives.append((os.path.basename(volume), volume + '/', os.path.basename(volume)))

		_removableCache = drives
		time.sleep(1)

def ejectDrive(driveName):
	if platform.system() == "Windows":
		cmd = [os.path.abspath(os.path.join(os.path.dirname(__file__), '..', 'EjectMedia.exe')), driveName]
	elif platform.system() == "Darwin":
		cmd = ["diskutil", "eject", driveName]
	else:
		cmd = ["umount", driveName]

	kwargs = {}
	if subprocess.mswindows:
		su = subprocess.STARTUPINFO()
		su.dwFlags |= subprocess.STARTF_USESHOWWINDOW
		su.wShowWindow = subprocess.SW_HIDE
		kwargs['startupinfo'] = su
	p = subprocess.Popen(cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, **kwargs)
	output = p.communicate()

	if p.wait():
		print output[0]
		print output[1]
		return False
	else:
		return True

if __name__ == '__main__':
	print getPossibleSDcardDrives()