from __future__ import absolute_import
from __future__ import division
from __future__ import print_function


import argparse
import os
import tempfile
import subprocess
import tensorflow as tf
import numpy as np
import tfimage as im
import threading
import time
import multiprocessing

edge_pool = None


parser = argparse.ArgumentParser()
parser.add_argument("--input_dir", required=True, help="path to folder containing images")
parser.add_argument("--output_dir", required=True, help="output path")
parser.add_argument("--operation", required=True, choices=["grayscale", "resize", "blank", "combine", "edges"])
parser.add_argument("--workers", type=int, default=1, help="number of workers")
# resize
parser.add_argument("--pad", action="store_true", help="pad instead of crop for resize operation")
parser.add_argument("--size", type=int, default=256, help="size to use for resize operation")
# combine
parser.add_argument("--b_dir", type=str, help="path to folder containing B images for combine operation")
a = parser.parse_args()


def resize(src):
    height, width, _ = src.shape
    dst = src
    if height != width:
        if a.pad:
            size = max(height, width)
            # pad to correct ratio
            oh = (size - height) // 2
            ow = (size - width) // 2
            dst = im.pad(image=dst, offset_height=oh, offset_width=ow, target_height=size, target_width=size)
        else:
            # crop to correct ratio
            size = min(height, width)
            oh = (height - size) // 2
            ow = (width - size) // 2
            dst = im.crop(image=dst, offset_height=oh, offset_width=ow, target_height=size, target_width=size)

    assert(dst.shape[0] == dst.shape[1])

    size, _, _ = dst.shape
    if size > a.size:
        dst = im.downscale(images=dst, size=[a.size, a.size])
    elif size < a.size:
        dst = im.upscale(images=dst, size=[a.size, a.size])
    return dst


def blank(src):
    height, width, _ = src.shape
    if height != width:
        raise Exception("non-square image")

    image_size = width
    size = int(image_size * 0.3)
    offset = int(image_size / 2 - size / 2)

    dst = src
    dst[offset:offset + size,offset:offset + size,:] = np.ones([size, size, 3])
    return dst


def combine(src, src_path):
    if a.b_dir is None:
        raise Exception("missing b_dir")

    # find corresponding file in b_dir, could have a different extension
    basename, _ = os.path.splitext(os.path.basename(src_path))
    for ext in [".png", ".jpg"]:
        sibling_path = os.path.join(a.b_dir, basename + ext)
        if os.path.exists(sibling_path):
            sibling = im.load(sibling_path)
            break
    else:
        raise Exception("could not find sibling image for " + src_path)

    # make sure that dimensions are correct
    height, width, _ = src.shape
    if height != sibling.shape[0] or width != sibling.shape[1]:
        raise Exception("differing sizes")
    
    # convert both images to RGB if necessary
    if src.shape[2] == 1:
        src = im.grayscale_to_rgb(images=src)

    if sibling.shape[2] == 1:
        sibling = im.grayscale_to_rgb(images=sibling)

    # remove alpha channel
    if src.shape[2] == 4:
        src = src[:,:,:3]
    
    if sibling.shape[2] == 4:
        sibling = sibling[:,:,:3]

    return np.concatenate([src, sibling], axis=1)


def grayscale(src):
    return im.grayscale_to_rgb(images=im.rgb_to_grayscale(images=src))


net = None
def run_caffe(src):
    # lazy load caffe and create net
    global net
    if net is None:
        # don't require caffe unless we are doing edge detection
        os.environ["GLOG_minloglevel"] = "2" # disable logging from caffe
        import caffe
        # using this requires using the docker image or assembling a bunch of dependencies
        # and then changing these hardcoded paths
        net = caffe.Net("/opt/caffe/examples/hed/deploy.prototxt", "/opt/caffe/hed_pretrained_bsds.caffemodel", caffe.TEST)
        
    net.blobs["data"].reshape(1, *src.shape)
    net.blobs["data"].data[...] = src
    net.forward()
    return net.blobs["sigmoid-fuse"].data[0][0,:,:]

    
def edges(src):
    # based on https://github.com/phillipi/pix2pix/blob/master/scripts/edges/batch_hed.py
    # and https://github.com/phillipi/pix2pix/blob/master/scripts/edges/PostprocessHED.m
    import scipy.io
    src = src * 255
    border = 128 # put a padding around images since edge detection seems to detect edge of image
    src = src[:,:,:3] # remove alpha channel if present
    src = np.pad(src, ((border, border), (border, border), (0,0)), "reflect")
    src = src[:,:,::-1]
    src -= np.array((104.00698793,116.66876762,122.67891434))
    src = src.transpose((2, 0, 1))

    # [height, width, channels] => [batch, channel, height, width]
    fuse = edge_pool.apply(run_caffe, [src])
    fuse = fuse[border:-border, border:-border]

    with tempfile.NamedTemporaryFile(suffix=".png") as png_file, tempfile.NamedTemporaryFile(suffix=".mat") as mat_file:
        scipy.io.savemat(mat_file.name, {"input": fuse})
        
        octave_code = r"""
E = 1-load(input_path).input;
E = imresize(E, [image_width,image_width]);
E = 1 - E;
E = single(E);
[Ox, Oy] = gradient(convTri(E, 4), 1);
[Oxx, ~] = gradient(Ox, 1);
[Oxy, Oyy] = gradient(Oy, 1);
O = mod(atan(Oyy .* sign(-Oxy) ./ (Oxx + 1e-5)), pi);
E = edgesNmsMex(E, O, 1, 5, 1.01, 1);
E = double(E >= max(eps, threshold));
E = bwmorph(E, 'thin', inf);
E = bwareaopen(E, small_edge);
E = 1 - E;
E = uint8(E * 255);
imwrite(E, output_path);
"""

        config = dict(
            input_path="'%s'" % mat_file.name,
            output_path="'%s'" % png_file.name,
            image_width=256,
            threshold=25.0/255.0,
            small_edge=5,
        )

        args = ["octave"]
        for k, v in config.items():
            args.extend(["--eval", "%s=%s;" % (k, v)])

        args.extend(["--eval", octave_code])
        try:
            subprocess.check_output(args, stderr=subprocess.STDOUT)
        except subprocess.CalledProcessError as e:
            print("octave failed")
            print("returncode:", e.returncode)
            print("output:", e.output)
            raise
        return im.load(png_file.name)


def process(src_path, dst_path):
    src = im.load(src_path)

    if a.operation == "grayscale":
        dst = grayscale(src)
    elif a.operation == "resize":
        dst = resize(src)
    elif a.operation == "blank":
        dst = blank(src)
    elif a.operation == "combine":
        dst = combine(src, src_path)
    elif a.operation == "edges":
        dst = edges(src)
    else:
        raise Exception("invalid operation")

    im.save(dst, dst_path)


complete_lock = threading.Lock()
start = None
num_complete = 0
total = 0

def complete():
    global num_complete, rate, last_complete

    with complete_lock:
        num_complete += 1
        now = time.time()
        elapsed = now - start
        rate = num_complete / elapsed
        if rate > 0:
            remaining = (total - num_complete) / rate
        else:
            remaining = 0

        print("%d/%d complete  %0.2f images/sec  %dm%ds elapsed  %dm%ds remaining" % (num_complete, total, rate, elapsed // 60, elapsed % 60, remaining // 60, remaining % 60))

        last_complete = now


def main():
    if not os.path.exists(a.output_dir):
        os.makedirs(a.output_dir)

    src_paths = []
    dst_paths = []

    skipped = 0
    for src_path in im.find(a.input_dir):
        name, _ = os.path.splitext(os.path.basename(src_path))
        dst_path = os.path.join(a.output_dir, name + ".png")
        if os.path.exists(dst_path):
            skipped += 1
        else:
            src_paths.append(src_path)
            dst_paths.append(dst_path)
    
    print("skipping %d files that already exist" % skipped)
            
    global total
    total = len(src_paths)
    
    print("processing %d files" % total)

    global start
    start = time.time()
    
    if a.operation == "edges":
        # use a multiprocessing pool for this operation so it can use multiple CPUs
        # create the pool before we launch processing threads
        global edge_pool
        edge_pool = multiprocessing.Pool(a.workers)

    if a.workers == 1:
        with tf.Session() as sess:
            for src_path, dst_path in zip(src_paths, dst_paths):
                process(src_path, dst_path)
                complete()
    else:
        queue = tf.train.input_producer(zip(src_paths, dst_paths), shuffle=False, num_epochs=1)
        dequeue_op = queue.dequeue()

        def worker(coord):
            with sess.as_default():
                while not coord.should_stop():
                    try:
                        src_path, dst_path = sess.run(dequeue_op)
                    except tf.errors.OutOfRangeError:
                        coord.request_stop()
                        break

                    process(src_path, dst_path)
                    complete()

        # init epoch counter for the queue
        local_init_op = tf.local_variables_initializer()
        with tf.Session() as sess:
            sess.run(local_init_op)

            coord = tf.train.Coordinator()
            threads = tf.train.start_queue_runners(coord=coord)
            for i in range(a.workers):
                t = threading.Thread(target=worker, args=(coord,))
                t.start()
                threads.append(t)
            
            try:
                coord.join(threads)
            except KeyboardInterrupt:
                coord.request_stop()
                coord.join(threads)

main()