import os
import sys
import re
import random

import numpy as np
import cv2 as cv

sys.path.append("..")
sys.path.append("../../src")
from annotations import DataFile,computeBoundingBox,Corners,EPoint
from geometry import Line
from kerokero.transformation_matrices import getIdentity,getRotation,getTranslation,getScale,getMirroring,getProjection

random.seed(361)


class Sample:
	SIDE=224

	def __init__(self,img,grid):
		""":param img: a greyscale image as a 2D np.uint8
		:param grid: iterable of 4 EPoints, ie. Corners"""
		self.img=img
		self.grid=grid

	def transform(self):
		""":return: (img, grid), where img is a 2D np.float32 with values in (0,1),
		grid [(float) x, (float) y, ...], with x, y in (-1,1)"""
		center=self._getCenter()
		m=getIdentity()
		t1=getTranslation(-center.x,-center.y)
		proj=getProjection()
		rot=getRotation()
		mir=getMirroring()
		for mi in [t1,mir,proj,rot]:
			m=np.matmul(mi,m)
		m=np.matmul(self._computeCrop(m),m)
		img=cv.warpPerspective(self.img,m,(self.SIDE,self.SIDE))
		img=np.float32(img)/128-1
		grid=Corners(c.transform(m) for c in self.grid)
		grid=list(map(lambda p: list(2*p/self.SIDE-EPoint(1,1)), grid))
		return (img,grid)

	def _getCenter(self):
		(a,b,c,d)=self.grid
		p=Line.fromPoints(a,c)
		q=Line.fromPoints(b,d)
		return p.intersect(q)

	def _computeCrop(self,m):
		grid=Corners(c.transform(m) for c in self.grid)
		(x1,y1,x2,y2)=computeBoundingBox(grid)
		(wg,hg)=(x2-x1,y2-y1)
		(left,top,right,bottom)=[random.uniform(0.05,0.2) for i in range(4)]
		t2=getTranslation(left*wg-x1, top*hg-y1)
		scale=getScale(self.SIDE/(wg*(1+left+right)), self.SIDE/(hg*(1+top+bottom)))
		return np.matmul(scale,t2)

	def show(self):
		img=cv.cvtColor(self.img,cv.COLOR_GRAY2BGR)
		for c in self.grid:
			cv.circle(img,(int(c.x),int(c.y)),3,[0,255,0],-1)
		show(img)


def traverseDirs(root):
	stack=[root]
	while len(stack)>0:
		d=stack.pop()
		contents=sorted(os.scandir(d),key=lambda f: f.name,reverse=True)
		if any(f.name=="annotations.json.gz" for f in contents):
			print(d)
			yield d
		for f in contents:
			if f.is_dir(): stack.append(f.path)


def harvestDir(path):
	annotations=DataFile(os.path.join(path,"annotations.json.gz"))
	imgFilter=lambda f: f.is_file() and re.match(r".*\.(jpg|jpeg|png|gif)$", f.name.lower())
	files=sorted(filter(imgFilter,os.scandir(path)),key=lambda f: f.name)
	boards=annotations["."]
	for f in files:
		img=cv.imread(f.path)
		img=cv.cvtColor(img,cv.COLOR_BGR2GRAY)
		for b in boards:
			sample=Sample(img,b.grid)
			# sample.show()
			(transformedImg,label)=sample.transform()
			# Sample(np.uint8((transformedImg+1)*128),map(lambda c: (c+EPoint(1,1))*Sample.SIDE/2,transformedGrid)).show()
			yield (transformedImg,label)


def loadDataset(root):
	testRatio=0.1
	trainRatio=1-testRatio
	images=[]
	labels=[]
	for d in traverseDirs(root):
		for (img,label) in harvestDir(d):
			images.append(img)
			labels.append(label)
	n=len(images)
	keys=list(range(n))
	random.shuffle(keys)
	images=[images[k] for k in keys]
	labels=[labels[k] for k in keys]
	m=int(n*trainRatio)
	return (
		(np.float32(images[:m]),np.float32(labels[:m])),
		(np.float32(images[m:]),np.float32(labels[m:]))
	)


def show(img,filename="x"):
	cv.imshow(filename,img)
	cv.waitKey(0)
	cv.destroyAllWindows()


if __name__=="__main__":
	((trainImages,trainLabels),(testImages,testLabels))=loadDataset(sys.argv[1])
	np.savez_compressed(
		sys.argv[2],
		trainImages=trainImages,
		trainLabels=trainLabels,
		testImages=testImages,
		testLabels=testLabels
	)