package util

import (
	"basic.com/pubsub/protomsg.git"
	"basic.com/valib/godraw.git"
	"image"
	"image/color"
)

// 按尺寸去切图
func SubCutImg(src *protomsg.Image, rect *protomsg.Rect, enlarge int) ([]byte, error){
	bkImg, _ := godraw.ToImage(src.Data, int(src.Width), int(src.Height))

	rectNew := image.Rect(EnlargeCut(rect, int(src.Width), int(src.Height), enlarge))
	subImg := bkImg.(*image.RGBA).SubImage(rectNew)

	bytes,err := godraw.ImageToJpeg(subImg, nil)
	if err != nil {
		return nil, err
	}
	return bytes, nil
}

// 长宽变为一比一，每边各扩百分之...
func EnlargeCut(rect *protomsg.Rect, maxW,maxH int, enlargePer int) (x0_new, y0_new, x1_new, y1_new int) {
	// 先把长宽变为一比一
	x0 := int(rect.Left)
	y0 := int(rect.Top)
	x1 := int(rect.Right)
	y1 := int(rect.Bottom)

	chazhi := (y1 - y0) - (x1 - x0)
	x0 = x0 - chazhi/2
	if x0 < 0 {
		x0 = 0
	}
	x1 = x1 + chazhi/2
	if x1 > maxW {
		x1 = maxW
	}

	// 再把每边各扩大百分之...
	enlarge := float32(enlargePer / 100)
	x0_new = int((1+enlarge)*float32(x0) - enlarge*float32(x1))
	if x0_new < 0 {
		x0_new = 0
	}
	x1_new = int((1+enlarge)*float32(x1) - enlarge*float32(x0))
	if x1_new > maxW {
		x1_new = maxW
	}
	y0_new = int((1+enlarge)*float32(y0) - enlarge*float32(y1))
	if y0_new < 0 {
		y0_new = 0
	}
	y1_new = int((1+enlarge)*float32(y1) - enlarge*float32(y0))
	if y1_new > maxH {
		y1_new = maxH
	}

	return x0_new, y0_new, x1_new, y1_new
}

// 长宽变为一比一，每边各扩百分之20
func EnlargeSizeForCar(x0, y0, x1, y1 int, i protomsg.Image) (x0_new, y0_new, x1_new, y1_new int) {
	// 先把长宽变为一比一
	chazhi := (y1 - y0) - (x1 - x0)
	x0 = x0 - chazhi/2
	if x0 < 0 {
		x0 = 0
	}
	x1 = x1 + chazhi/2
	if x1 > int(i.Width) {
		x1 = int(i.Width)
	}

	// 再把每边各扩大百分之20
	enlarge := float32(0.2)
	x0_new = int((1+enlarge)*float32(x0) - enlarge*float32(x1))
	if x0_new < 0 {
		x0_new = 0
	}
	x1_new = int((1+enlarge)*float32(x1) - enlarge*float32(x0))
	if x1_new > int(i.Width) {
		x1_new = int(i.Width)
	}
	y0_new = int((1+enlarge)*float32(y0) - enlarge*float32(y1))
	if y0_new < 0 {
		y0_new = 0
	}
	y1_new = int((1+enlarge)*float32(y1) - enlarge*float32(y0))
	if y1_new > int(i.Height) {
		y1_new = int(i.Height)
	}
	return
}

// 不扩边
func EnlargeSize(x0, y0, x1, y1 int, i protomsg.Image) (int, int, int, int) {

	// 先把长宽变为一比一
	chazhi := (y1 - y0) - (x1 - x0)
	x0 = x0 - chazhi/2
	if x0 < 0 {
		x0 = 0
	}
	x1 = x1 + chazhi/2
	if x1 > int(i.Width) {
		x1 = int(i.Width)
	}

	if y0 < 0 {
		y0 = 0
	}

	if y1 > int(i.Height) {
		y1 = int(i.Height)
	}

	return x0, y0, x1, y1
}

// 长宽变为一比一，每边各扩百分之50
func EnlargeSizeForTem(x0, y0, x1, y1 int, i protomsg.Image) (x0_new, y0_new, x1_new, y1_new int) {
	// 先把长宽变为一比一
	chazhi := (y1 - y0) - (x1 - x0)
	x0 = x0 - chazhi/2
	if x0 < 0 {
		x0 = 0
	}
	x1 = x1 + chazhi/2
	if x1 > int(i.Width) {
		x1 = int(i.Width)
	}

	// 再把每边各扩大百分之50
	enlarge := float32(0.5)
	x0_new = int((1+enlarge)*float32(x0) - enlarge*float32(x1))
	if x0_new < 0 {
		x0_new = 0
	}
	x1_new = int((1+enlarge)*float32(x1) - enlarge*float32(x0))
	if x1_new > int(i.Width) {
		x1_new = int(i.Width)
	}
	y0_new = int((1+enlarge)*float32(y0) - enlarge*float32(y1))
	if y0_new < 0 {
		y0_new = 0
	}
	y1_new = int((1+enlarge)*float32(y1) - enlarge*float32(y0))
	if y1_new > int(i.Height) {
		y1_new = int(i.Height)
	}
	return
}

func drawLine(img *image.RGBA, x0, y0, x1, y1 int, c color.Color) {
	var dx int
	if x1 > x0 {
		dx = x1 - x0
	} else {
		dx = x0 - x1
	}
	var dy int
	if y1 > y0 {
		dy = y1 - y0
	} else {
		dy = y0 - y1
	}

	sx, sy := 1, 1
	if x0 >= x1 {
		sx = -1
	}
	if y0 >= y1 {
		sy = -1
	}
	err := dx - dy

	for {
		img.Set(x0, y0, c)
		if x0 == x1 && y0 == y1 {
			return
		}
		e2 := err * 2
		if e2 > -dy {
			err -= dy
			x0 += sx
		}
		if e2 < dx {
			err += dx
			y0 += sy
		}
	}
}

func DrawRect(img *image.RGBA, x0, y0, x1, y1 int, c color.Color) {
	drawLine(img, x0, y0, x1, y0, c)
	drawLine(img, x1, y0, x1, y1, c)
	drawLine(img, x1, y1, x0, y1, c)
	drawLine(img, x0, y1, x0, y0, c)
}