from ijutils import *

RANGE = (10, 40)
STEP_SIZE = 2.0

diam_disk = cover_detection.config.diameter_disk
diam_target = cover_detection.config.diameter_target
diam_dewar = cover_detection.config.diameter_dewar
threshold_method = cover_detection.config.threshold_method
center_x, center_y = ( cover_detection.config.center_x,  cover_detection.config.center_y)
radius_dewar = diam_dewar/2.0
roi = Rectangle(int(center_x-radius_dewar), int(center_y-radius_dewar), int(diam_dewar), int(diam_dewar))
area_disc = int(pow(diam_disk/2,2) * math.pi)
area_target = int(pow(diam_target/2,2) * math.pi)
area = area_disc - area_target
if TARGET_HOLES:
    area -= int(4* pow(12/2,2) * math.pi)
debug=True
settling_time = cam.getAcquirePeriod()/1000.0 + 0.3

class Fitness(Readable):
    def read(self):     
       try:
           ip = load_image(ImagingUtils.grayscale(img.output, None))
           set_circle_mask(ip.getProcessor(), center_x=center_x, center_y=center_y, radius=radius_dewar, bitwise=False)    
           #it = auto_threshold(ip, dark_background=True, method=threshold_method, in_place=False) 
           it = threshold(ip, 128, 255, in_place=False)
           binary_open(it, dark_background=True,   iterations=1, count=1); 
           binary_open(it, dark_background=False,   iterations=1, count=1);        
           if debug:
                ImageBuffer.saveImage(it.getBufferedImage(), os.path.abspath(expand_path("{images}/ExposureScan/" + str( cam.getExposure()) + ".png")), "png")    
           
           h = get_histogram(it)
           b,w= h[0], h[-1]           
           error = abs(w-area)           
           return error
       except:
            print sys.exc_info()[1]

       
       
class Exposure(Writable):
    def write(self,pos):
        cam.setExposure(pos)

fitness=Fitness()
exposure=Exposure()

ret = lscan(exposure,fitness,RANGE[0], RANGE[1], STEP_SIZE, settling_time, save=False)
y, x = ret.getReadable(0), ret.getPositions(0)
m=x[y.index(min(y))]
p=get_plots()[0]
p.addMarker(m, p.AxisId.X, str(m), Color.RED)
print "Setting exposure = ", m
exposure.write(m)
time.sleep(settling_time)
cover_detection.grab_ref_image()
set_return("Optimal exposure: " + str(m))