from __future__ import print_function
import _pickle as pickle

__author__ = 'licheng'

"""
This interface provides access to four datasets:
1) refclef
2) refcoco
3) refcoco+
4) refcocog
split by unc and google

The following API functions are defined:
REFER      - REFER api class
getRefIds  - get ref ids that satisfy given filter conditions.
getAnnIds  - get ann ids that satisfy given filter conditions.
getImgIds  - get image ids that satisfy given filter conditions.
getCatIds  - get category ids that satisfy given filter conditions.
loadRefs   - load refs with the specified ref ids.
loadAnns   - load anns with the specified ann ids.
loadImgs   - load images with the specified image ids.
loadCats   - load category names with the specified category ids.
getRefBox  - get ref's bounding box [x, y, w, h] given the ref_id
showRef    - show image, segmentation or box of the referred object with the ref
getMask    - get mask and area of the referred object given ref
showMask   - show mask of the referred object given ref
"""

import sys
import os.path as osp
import json
#import cPickle as pickle
import time
import itertools
import skimage.io as io
import matplotlib.pyplot as plt
from matplotlib.collections import PatchCollection
from matplotlib.patches import Polygon, Rectangle
from pprint import pprint
import numpy as np
from tools.refer.external import mask
# import cv2
# from skimage.measure import label, regionprops

class REFER:

	def __init__(self, data_root, dataset='refcoco', splitBy='unc'):
		# provide data_root folder which contains refclef, refcoco, refcoco+ and refcocog
		# also provide dataset name and splitBy information
		# e.g., dataset = 'refcoco', splitBy = 'unc'
		print('loading dataset %s into memory...' % dataset)
		self.ROOT_DIR = osp.abspath(osp.dirname(__file__))
		self.DATA_DIR = osp.join(data_root, dataset)
		if dataset in ['refcoco', 'refcoco+', 'refcocog']:
			self.IMAGE_DIR = osp.join(data_root, 'images/mscoco/images/train2014')
		elif dataset == 'refclef':
			self.IMAGE_DIR = osp.join(data_root, 'images/saiapr_tc-12')
		else:
			print('No refer dataset is called [%s]' % dataset)
			sys.exit()

		# load refs from data/dataset/refs(dataset).json
		tic = time.time()
		ref_file = osp.join(self.DATA_DIR, 'refs('+splitBy+').p')
		self.data = {}
		self.data['dataset'] = dataset
		self.data['refs'] = pickle.load(open(ref_file, 'rb'))

		# load annotations from data/dataset/instances.json
		instances_file = osp.join(self.DATA_DIR, 'instances.json')
		instances = json.load(open(instances_file, 'r'))
		self.data['images'] = instances['images']
		self.data['annotations'] = instances['annotations']
		self.data['categories'] = instances['categories']

		# create index
		self.createIndex()
		print('DONE (t=%.2fs)' % (time.time()-tic))

	def createIndex(self):
		# create sets of mapping
		# 1)  Refs: 	 	{ref_id: ref}
		# 2)  Anns: 	 	{ann_id: ann}
		# 3)  Imgs:		 	{image_id: image}
		# 4)  Cats: 	 	{category_id: category_name}
		# 5)  Sents:     	{sent_id: sent}
		# 6)  imgToRefs: 	{image_id: refs}
		# 7)  imgToAnns: 	{image_id: anns}
		# 8)  refToAnn:  	{ref_id: ann}
		# 9)  annToRef:  	{ann_id: ref}
		# 10) catToRefs: 	{category_id: refs}
		# 11) sentToRef: 	{sent_id: ref}
		# 12) sentToTokens: {sent_id: tokens}
		print('creating index...')
		# fetch info from instances
		Anns, Imgs, Cats, imgToAnns = {}, {}, {}, {}
		for ann in self.data['annotations']:
			Anns[ann['id']] = ann
			imgToAnns[ann['image_id']] = imgToAnns.get(ann['image_id'], []) + [ann]
		for img in self.data['images']:
			Imgs[img['id']] = img
		for cat in self.data['categories']:
			Cats[cat['id']] = cat['name']

		# fetch info from refs
		Refs, imgToRefs, refToAnn, annToRef, catToRefs = {}, {}, {}, {}, {}
		Sents, sentToRef, sentToTokens = {}, {}, {}
		for ref in self.data['refs']:
			# ids
			ref_id = ref['ref_id']
			ann_id = ref['ann_id']
			category_id = ref['category_id']
			image_id = ref['image_id']

			# add mapping related to ref
			Refs[ref_id] = ref
			imgToRefs[image_id] = imgToRefs.get(image_id, []) + [ref]
			catToRefs[category_id] = catToRefs.get(category_id, []) + [ref]
			refToAnn[ref_id] = Anns[ann_id]
			annToRef[ann_id] = ref

			# add mapping of sent
			for sent in ref['sentences']:
				Sents[sent['sent_id']] = sent
				sentToRef[sent['sent_id']] = ref
				sentToTokens[sent['sent_id']] = sent['tokens']

		# create class members
		self.Refs = Refs
		self.Anns = Anns
		self.Imgs = Imgs
		self.Cats = Cats
		self.Sents = Sents
		self.imgToRefs = imgToRefs
		self.imgToAnns = imgToAnns
		self.refToAnn = refToAnn
		self.annToRef = annToRef
		self.catToRefs = catToRefs
		self.sentToRef = sentToRef
		self.sentToTokens = sentToTokens
		print('index created.')

	def getRefIds(self, image_ids=[], cat_ids=[], ref_ids=[], split=''):
		image_ids = image_ids if type(image_ids) == list else [image_ids]
		cat_ids = cat_ids if type(cat_ids) == list else [cat_ids]
		ref_ids = ref_ids if type(ref_ids) == list else [ref_ids]

		if len(image_ids)==len(cat_ids)==len(ref_ids)==len(split)==0:
			refs = self.data['refs']
		else:
			if not len(image_ids) == 0:
				refs = [self.imgToRefs[image_id] for image_id in image_ids]
			else:
				refs = self.data['refs']
			if not len(cat_ids) == 0:
				refs = [ref for ref in refs if ref['category_id'] in cat_ids]
			if not len(ref_ids) == 0:
				refs = [ref for ref in refs if ref['ref_id'] in ref_ids]
			if not len(split) == 0:
				if split in ['testA', 'testB', 'testC']:
					refs = [ref for ref in refs if split[-1] in ref['split']] # we also consider testAB, testBC, ...
				elif split in ['testAB', 'testBC', 'testAC']:
					refs = [ref for ref in refs if ref['split'] == split]  # rarely used I guess...
				elif split == 'test':
					refs = [ref for ref in refs if 'test' in ref['split']]
				elif split == 'train' or split == 'val':
					refs = [ref for ref in refs if ref['split'] == split]
				else:
					print('No such split [%s]' % split)
					sys.exit()
		ref_ids = [ref['ref_id'] for ref in refs]
		return ref_ids

	def getAnnIds(self, image_ids=[], cat_ids=[], ref_ids=[]):
		image_ids = image_ids if type(image_ids) == list else [image_ids]
		cat_ids = cat_ids if type(cat_ids) == list else [cat_ids]
		ref_ids = ref_ids if type(ref_ids) == list else [ref_ids]

		if len(image_ids) == len(cat_ids) == len(ref_ids) == 0:
			ann_ids = [ann['id'] for ann in self.data['annotations']]
		else:
			if not len(image_ids) == 0:
				lists = [self.imgToAnns[image_id] for image_id in image_ids if image_id in self.imgToAnns]  # list of [anns]
				anns = list(itertools.chain.from_iterable(lists))
			else:
				anns = self.data['annotations']
			if not len(cat_ids) == 0:
				anns = [ann for ann in anns if ann['category_id'] in cat_ids]
			ann_ids = [ann['id'] for ann in anns]
			if not len(ref_ids) == 0:
				ids = set(ann_ids).intersection(set([self.Refs[ref_id]['ann_id'] for ref_id in ref_ids]))
		return ann_ids

	def getImgIds(self, ref_ids=[]):
		ref_ids = ref_ids if type(ref_ids) == list else [ref_ids]

		if not len(ref_ids) == 0:
			image_ids = list(set([self.Refs[ref_id]['image_id'] for ref_id in ref_ids]))
		else:
			image_ids = self.Imgs.keys()
		return image_ids

	def getCatIds(self):
		return self.Cats.keys()

	def loadRefs(self, ref_ids=[]):
		if type(ref_ids) == list:
			return [self.Refs[ref_id] for ref_id in ref_ids]
		elif type(ref_ids) == int:
			return [self.Refs[ref_ids]]

	def loadAnns(self, ann_ids=[]):
		if type(ann_ids) == list:
			return [self.Anns[ann_id] for ann_id in ann_ids]
		elif type(ann_ids) == int or type(ann_ids) == unicode:
			return [self.Anns[ann_ids]]

	def loadImgs(self, image_ids=[]):
		if type(image_ids) == list:
			return [self.Imgs[image_id] for image_id in image_ids]
		elif type(image_ids) == int:
			return [self.Imgs[image_ids]]

	def loadCats(self, cat_ids=[]):
		if type(cat_ids) == list:
			return [self.Cats[cat_id] for cat_id in cat_ids]
		elif type(cat_ids) == int:
			return [self.Cats[cat_ids]]

	def getRefBox(self, ref_id):
		ref = self.Refs[ref_id]
		ann = self.refToAnn[ref_id]
		return ann['bbox']  # [x, y, w, h]

	def showRef(self, ref, seg_box='seg'):
		ax = plt.gca()
		# show image
		image = self.Imgs[ref['image_id']]
		I = io.imread(osp.join(self.IMAGE_DIR, image['file_name']))
		ax.imshow(I)
		# show refer expression
		for sid, sent in enumerate(ref['sentences']):
			print('%s. %s' % (sid+1, sent['sent']))
		# show segmentations
		if seg_box == 'seg':
			ann_id = ref['ann_id']
			ann = self.Anns[ann_id]
			polygons = []
			color = []
			c = 'none'
			if type(ann['segmentation'][0]) == list:
				# polygon used for refcoco*
				for seg in ann['segmentation']:
					poly = np.array(seg).reshape((len(seg)/2, 2))
					polygons.append(Polygon(poly, True, alpha=0.4))
					color.append(c)
				p = PatchCollection(polygons, facecolors=color, edgecolors=(1,1,0,0), linewidths=3, alpha=1)
				ax.add_collection(p)  # thick yellow polygon
				p = PatchCollection(polygons, facecolors=color, edgecolors=(1,0,0,0), linewidths=1, alpha=1)
				ax.add_collection(p)  # thin red polygon
			else:
				# mask used for refclef
				rle = ann['segmentation']
				m = mask.decode(rle)
				img = np.ones( (m.shape[0], m.shape[1], 3) )
				color_mask = np.array([2.0,166.0,101.0])/255
				for i in range(3):
					img[:,:,i] = color_mask[i]
				ax.imshow(np.dstack( (img, m*0.5) ))
		# show bounding-box
		elif seg_box == 'box':
			ann_id = ref['ann_id']
			ann = self.Anns[ann_id]
			bbox = 	self.getRefBox(ref['ref_id'])
			box_plot = Rectangle((bbox[0], bbox[1]), bbox[2], bbox[3], fill=False, edgecolor='green', linewidth=3)
			ax.add_patch(box_plot)

	def getMask(self, ref):
		# return mask, area and mask-center
		ann = self.refToAnn[ref['ref_id']]
		image = self.Imgs[ref['image_id']]
		if type(ann['segmentation'][0]) == list: # polygon
			rle = mask.frPyObjects(ann['segmentation'], image['height'], image['width'])
		else:
			rle = ann['segmentation']
		m = mask.decode(rle)
		m = np.sum(m, axis=2)  # sometimes there are multiple binary map (corresponding to multiple segs)
		m = m.astype(np.uint8) # convert to np.uint8
		# compute area
		area = sum(mask.area(rle))  # should be close to ann['area']
		return {'mask': m, 'area': area}
		# # position
		# position_x = np.mean(np.where(m==1)[1]) # [1] means columns (matlab style) -> x (c style)
		# position_y = np.mean(np.where(m==1)[0]) # [0] means rows (matlab style)    -> y (c style)
		# # mass position (if there were multiple regions, we use the largest one.)
		# label_m = label(m, connectivity=m.ndim)
		# regions = regionprops(label_m)
		# if len(regions) > 0:
		# 	largest_id = np.argmax(np.array([props.filled_area for props in regions]))
		# 	largest_props = regions[largest_id]
		# 	mass_y, mass_x = largest_props.centroid
		# else:
		# 	mass_x, mass_y = position_x, position_y
		# # if centroid is not in mask, we find the closest point to it from mask
		# if m[mass_y, mass_x] != 1:
		# 	print 'Finding closes mask point ...'
		# 	kernel = np.ones((10, 10),np.uint8)
		# 	me = cv2.erode(m, kernel, iterations = 1)
		# 	points = zip(np.where(me == 1)[0].tolist(), np.where(me == 1)[1].tolist())  # row, col style
		# 	points = np.array(points)
		# 	dist   = np.sum((points - (mass_y, mass_x))**2, axis=1)
		# 	id     = np.argsort(dist)[0]
		# 	mass_y, mass_x = points[id]
		# 	# return
		# return {'mask': m, 'area': area, 'position_x': position_x, 'position_y': position_y, 'mass_x': mass_x, 'mass_y': mass_y}
		# # show image and mask
		# I = io.imread(osp.join(self.IMAGE_DIR, image['file_name']))
		# plt.figure()
		# plt.imshow(I)
		# ax = plt.gca()
		# img = np.ones( (m.shape[0], m.shape[1], 3) )
		# color_mask = np.array([2.0,166.0,101.0])/255
		# for i in range(3):
		#     img[:,:,i] = color_mask[i]
		# ax.imshow(np.dstack( (img, m*0.5) ))
		# plt.show()

	def showMask(self, ref):
		M = self.getMask(ref)
		msk = M['mask']
		ax = plt.gca()
		ax.imshow(msk)


if __name__ == '__main__':
	refer = REFER(dataset='refcocog', splitBy='google')
	ref_ids = refer.getRefIds()
	print(len(ref_ids))

	print(len(refer.Imgs))
	print(len(refer.imgToRefs))

	ref_ids = refer.getRefIds(split='train')
	print('There are %s training referred objects.' % len(ref_ids))

	for ref_id in ref_ids:
		ref = refer.loadRefs(ref_id)[0]
		if len(ref['sentences']) < 2:
			continue

		pprint(ref)
		print('The label is %s.' % refer.Cats[ref['category_id']])
		plt.figure()
		refer.showRef(ref, seg_box='box')
		plt.show()

		# plt.figure()
		# refer.showMask(ref)
		# plt.show()
