#!/usr/bin/python
# Network Camera Interface for the Flex Stack
# This application collects jpeg images from
# a network camera and generates thumbnails
# which are uploaded to a host computer.  The
# host can then select only the best images
# to download the high resolution versions of.
# This demo is intended to mimic low bandwidth
# telepresence environments such as the Mars
# Rovers.

from time import time
from os import system, path
import sys

class RmException(Exception): pass
class WgetException(Exception): pass
class UploadException(Exception): pass
class MvException(Exception): pass
class TnException(Exception): pass

LS = '/bin/ls -al'
RM = '/bin/rm'
WGET = '/bin/wget -q'
UPLOAD = 'lsz -b --zmodem ' 
MOVE = '/bin/mv'
JPGTN = '/bin/jpgtn -p tn- -s '
nullify = ' > /dev/null 2>&1'

#imName = 'image.jpg'
#imUrl = 'http://10.0.0.20/jpg/'
#imRepo = '/mnt/sd/images/'

imName = 'fred.jpg'
imUrl = 'http://10.0.0.2/'
imRepo = '/tmp/'
tnSize = 80 #pixels

def getImage():
    cmd = WGET + ' ' + imUrl + imName + nullify
    success = system(cmd)
    if success != 0:
        raise WgetException, 'Failed to getImage()'
       
def saveImage(timeOfDay='bfin-'):
    cmd = MOVE + ' ' + imName + ' ' + imRepo + timeOfDay + '.jpg' + nullify
    if path.exists(imRepo):    
        success = system(cmd)
        if success != 0:
            raise MvException, 'Failed to saveImage()'
        images.append(imRepo + timeOfDay + '.jpg')
    else:
        info = imRepo + ' does not exist'
        raise MvException, info
       
def mkThumbnail(timeOfDay):
    """
    makes a thumbnail of the image that is passed in.
    need to coorelate to the high res image that is
    stored on the sd card.
    """
    cmd = JPGTN + str(tnSize) + ' ' + imRepo + timeOfDay + '.jpg' #+ nullify
    success = system(cmd)
    if success != 0:
        raise TnException, 'Failed to create thumbnail (is jpgtn executable?)'
   
def rmThumbnail(imFile):
    cmd = RM + ' ' + imFile + nullify
    suc = system(cmd)
    if suc != 0:
        raise rmFailException

def rmFile(imFile):
    """
    same function but for any file.  
    specify the path and filename
    """
    cmd = RM + ' ' + imFile + nullify
    suc = system(cmd)
    if suc != 0:
        raise rmFailException


def xmitImage(imFile):
    """
    send the thumbnail/high res image to the host via ZMODEM protocol
    """
    if path.exists(imFile):
        if xmodem == True:        
            cmd = UPLOAD + imFile #+ nullify
            suc = system(cmd)
            if suc != 0:
                info = 'Failed to upload image ' + imFile
                raise UploadException, info
        else:
            diySend(imFile)
    else:
        info = imFile + ' does not exist, cancelled upload'
        raise UploadException, info

def diySend(imFile):
    """
    send file using custom protocol.
    filename.jpg:size in bytes:data
    """
    jpg = []
    #get file size in bytes
    cmd = LS + ' ' + imFile + ' > temp'
    system(cmd)
    fin = open('temp', 'r')
    line = fin.read()
    fin.close()
    filesize = line.split()[4]
    imFin = open(imFile, 'rb')
    rawImage = imFin.read()
    imFin.close()
    parts = imFile.split('/')
    imFileName = parts[ len(parts)-1 ]
    #rouge 0D0A sneak in while printing here
    sys.stdout.write( '$' + imFileName + ':' + filesize + ':' + rawImage )

    #for byte in rawImage:
    #    """
    #    if( repr(byte)[3:5] != '' && len(repr(byte)) > 3 ):
    #        jpg.append( repr(byte)[3:5] )
    #    elif ( len(repr(byte)) == 3 ):
    #        jpg.append( repr(byte) )
    #    """
    #    jpg.append( hex(ord(byte))[2:] )
    #print '$' + imFile + ':' + filesize + ':' + str.join('',jpg)

def sendThumbnail():   
    try:               
        now = str(time())
        tnFileName = 'tn-' + now +'.jpg'
        getImage()
        saveImage(now)
        mkThumbnail(now)
        xmitImage(tnFileName)
        rmThumbnail(tnFileName)
        return tnFileName
    except:
        raise

def getCmd():
    cmd = raw_input('cmd>')
    return cmd

def printHelp():
    print """FlexStack Remote Camera Demo
    HELP         - Print this menu
    DEBUG        - Toggle debugging output
    TN           - Capture image, generate thumbnail, 
                    and transmit thumbnail via XMODEM
    LG<filename> - Request full resolution image where 
                    <filename> is the name of the thumbnail
    """

def debug(excinfo):
    if debugging == True:
        exception = str(excinfo[0]).split('.')[1]
        print str(exception) + ' ' + str(excinfo[1])

####start here####
debugging = False
xmodem = False
cmd = ''
images = []

while cmd != 'quit':
    cmd = getCmd()
    if cmd == 'TN':
        try:
            sendThumbnail()
            if len(images) > 5:
                delme = images[5:]
                for oldfile in delme:
                    rmFile(oldfile)
                images = images[:5]
            print 'ACK'
        except:
            debug(sys.exc_info())
            print 'NAK'
    elif cmd[:2] == 'LG':
        try:
            xmitImage(imRepo + cmd[5:])
            print 'ACK'
        except:
            print 'NAK'
    elif cmd == 'HELP':
        printHelp()    
    elif cmd == 'DEBUG':        
        debugging = not debugging
        if(debugging):
            print 'Debugging is on'
        else:
            print 'Debugging is off'
    elif cmd == 'XMODEM':        
        xmodem = not xmodem
        if(xmodem):
            print 'Using XMODEM for upload'
        else:
            print 'Using diy protocol filename:size:data'
    elif cmd == 'CLEAN':
        print images
        if len(images) > 5:
            delme = images[5:]
            for oldfile in delme:
                rmFile(oldfile)
            images = images[:5]
        print images