import cv
import sys
import datetime
import os
import threading
import time
import shutil

# This threaded class monitors the src and dst folders for files
# If it finds some files in the spool folder, it copies them over to
# the snapshots folder and removes the originals
class FolderMonitor (threading.Thread):
    def __init__(self):
        threading.Thread.__init__(self)
        self.setDaemon(True)
    def run(self):

        while True:
            dirlist = os.listdir("spool/")
            print "Attempting to move spooled images to server"
            for filename in dirlist:
                try:
                    if os.path.exists("snapshots/"):
                        src = "spool/" + filename
                        dst = "snapshots/" + filename
                        os.system("cp " + src + " " + dst)
                        os.system("rm " + src)

                except IOError, e:
                    print "Error Jim- ", e
                except:
                    print "Unkown Error"

            time.sleep(20)

capture  = cv.CaptureFromCAM(0)
frame = cv.QueryFrame(capture)

if frame == None:
    print "Could not capture image from camera"
    sys.exit(0)

snapshot = cv.CloneImage(frame)

grey = cv.CreateImage( cv.GetSize(frame), 8, 1)
last = cv.CloneImage(grey)
diff = cv.CloneImage(grey)

cv.NamedWindow('frame')
cv.NamedWindow('snapshot')
cv.NamedWindow('detect')

font = cv.InitFont(cv.CV_FONT_HERSHEY_SIMPLEX, 0.5, 0.5, 0, 1, 4)

# Start the folder monitor
monitor = FolderMonitor()
monitor.start()

def countWhitePixels(img):
    (w,h) = cv.GetSize(img)
    size = float(w * h)
    white = float(cv.CountNonZero(img))
    return white / size


def main():
    while True:
        # Captures the current frame, greys and blurs it
        frame = cv.QueryFrame(capture)
        cv.CvtColor( frame, grey, cv.CV_BGR2GRAY)
        cv.EqualizeHist(grey,grey)
        cv.Smooth(grey, grey, cv.CV_BLUR,17)
        cv.Smooth(grey, grey, cv.CV_MEDIAN,17)

        # Calculate the difference between the last frame and the
        # current blurred frame
        cv.AbsDiff(grey, last, diff)

        threshold = 15
        color = 255
        cv.Threshold( diff, diff, threshold, color, cv.CV_THRESH_BINARY)

        weight = countWhitePixels(diff)
        if weight > 0.04:
            now = datetime.datetime.now()

            cv.Copy(frame, snapshot)
            cv.Rectangle(snapshot, (0,snapshot.height-30), (snapshot.width,snapshot.height), (0,0,0), cv.CV_FILLED)
            cv.PutText(snapshot, now.strftime("%d-%m-%Y %H:%M:%S"), (10,snapshot.height- 10), font, (255,255,255))

            filename = now.strftime("%d-%m-%Y_%H%M%S.jpg")
            if not os.path.exists("spool/" + filename):
                cv.SaveImage("spool/" + filename, snapshot)


        # Show all images because I am nice
        cv.ShowImage("frame", frame)
        cv.ShowImage("snapshot", snapshot)
        cv.ShowImage('detect', diff)

        # Copy the existing blurred image (last will always be 1 frame)
        # behind
        cv.Copy(grey, last)

        c = cv.WaitKey(2)
        if c==27:
            break


    return 0

if __name__ == '__main__':
    main()