<template>
	<view class="container">
		<view class="page-body uni-content-info">
			<view class='cropper-content'>
				<view v-if="isShowImg" class="uni-corpper"
					:style="'width:' + cropperInitW + 'px;height:' + cropperInitH + 'px;background:#000'">
					<view class="uni-corpper-content"
						:style="'width:' + cropperW + 'px;height:' + cropperH + 'px;left:' + cropperL + 'px;top:' + cropperT + 'px'">
						<image :src="imageSrc" :style="'width:' + cropperW + 'px;height:' + cropperH + 'px'"></image>
						<view class="uni-corpper-crop-box" @touchstart.stop="contentStartMove"
							@touchmove.stop="contentMoveing" @touchend.stop="contentTouchEnd"
							:style="'left:' + cutL + 'px;top:' + cutT + 'px;right:' + cutR + 'px;bottom:' + cutB + 'px'">
							<view class="uni-cropper-view-box">
								<view class="uni-cropper-dashed-h"></view>
								<view class="uni-cropper-dashed-v"></view>
								<view class="uni-cropper-line-t" data-drag="top" @touchstart.stop="dragStart"
									@touchmove.stop="dragMove"></view>
								<view class="uni-cropper-line-r" data-drag="right" @touchstart.stop="dragStart"
									@touchmove.stop="dragMove"></view>
								<view class="uni-cropper-line-b" data-drag="bottom" @touchstart.stop="dragStart"
									@touchmove.stop="dragMove"></view>
								<view class="uni-cropper-line-l" data-drag="left" @touchstart.stop="dragStart"
									@touchmove.stop="dragMove"></view>
								<view class="uni-cropper-point point-t" data-drag="top" @touchstart.stop="dragStart"
									@touchmove.stop="dragMove"></view>
								<view class="uni-cropper-point point-tr" data-drag="topTight"></view>
								<view class="uni-cropper-point point-r" data-drag="right" @touchstart.stop="dragStart"
									@touchmove.stop="dragMove"></view>
								<view class="uni-cropper-point point-rb" data-drag="rightBottom"
									@touchstart.stop="dragStart" @touchmove.stop="dragMove"></view>
								<view class="uni-cropper-point point-b" data-drag="bottom" @touchstart.stop="dragStart"
									@touchmove.stop="dragMove" @touchend.stop="dragEnd"></view>
								<view class="uni-cropper-point point-bl" data-drag="bottomLeft"></view>
								<view class="uni-cropper-point point-l" data-drag="left" @touchstart.stop="dragStart"
									@touchmove.stop="dragMove"></view>
								<view class="uni-cropper-point point-lt" data-drag="leftTop"></view>
							</view>
						</view>
					</view>
				</view>
			</view>
			<view class='cropper-config'>
				<button type="primary reverse" @click="getImage" style='margin-top: 30rpx;'> 选择头像 </button>
				<button type="warn" @click="getImageInfo" style='margin-top: 30rpx;'> 提交 </button>
			</view>
			<canvas canvas-id="myCanvas"
				:style="'position:absolute;border: 1px solid red; width:' + imageW + 'px;height:' + imageH + 'px;top:-9999px;left:-9999px;'"></canvas>
		</view>
	</view>
</template>

<script>
import config from '@/config'
import store from "@/store"
import { uploadAvatar } from "@/api/system/user"

const baseUrl = config.baseUrl
let sysInfo = uni.getSystemInfoSync()
let SCREEN_WIDTH = sysInfo.screenWidth
let PAGE_X, // 手按下的x位置
	PAGE_Y, // 手按下y的位置 
	PR = sysInfo.pixelRatio, // dpi
	T_PAGE_X, // 手移动的时候x的位置
	T_PAGE_Y, // 手移动的时候Y的位置
	CUT_L, // 初始化拖拽元素的left值
	CUT_T, // 初始化拖拽元素的top值
	CUT_R, // 初始化拖拽元素的
	CUT_B, // 初始化拖拽元素的
	CUT_W, // 初始化拖拽元素的宽度
	CUT_H, //  初始化拖拽元素的高度
	IMG_RATIO, // 图片比例
	IMG_REAL_W, // 图片实际的宽度
	IMG_REAL_H, // 图片实际的高度
	DRAFG_MOVE_RATIO = 1, //移动时候的比例,
	INIT_DRAG_POSITION = 100, // 初始化屏幕宽度和裁剪区域的宽度之差，用于设置初始化裁剪的宽度
	DRAW_IMAGE_W = sysInfo.screenWidth // 设置生成的图片宽度

export default {
	/**
	 * 页面的初始数据
	 */
	data() {
		return {
			imageSrc: store.getters.avatar,
			isShowImg: false,
			// 初始化的宽高
			cropperInitW: SCREEN_WIDTH,
			cropperInitH: SCREEN_WIDTH,
			// 动态的宽高
			cropperW: SCREEN_WIDTH,
			cropperH: SCREEN_WIDTH,
			// 动态的left top值
			cropperL: 0,
			cropperT: 0,

			transL: 0,
			transT: 0,

			// 图片缩放值
			scaleP: 0,
			imageW: 0,
			imageH: 0,

			// 裁剪框 宽高
			cutL: 0,
			cutT: 0,
			cutB: SCREEN_WIDTH,
			cutR: '100%',
			qualityWidth: DRAW_IMAGE_W,
			innerAspectRadio: DRAFG_MOVE_RATIO
		}
	},
	/**
	 * 生命周期函数--监听页面初次渲染完成
	 */
	onReady: function () {
		this.loadImage()
	},
	methods: {
		setData: function (obj) {
			let that = this
			Object.keys(obj).forEach(function (key) {
				that.$set(that.$data, key, obj[key])
			})
		},
		getImage: function () {
			var _this = this
			uni.chooseImage({
				success: function (res) {
					_this.setData({
						imageSrc: res.tempFilePaths[0],
					})
					_this.loadImage()
				},
			})
		},
		loadImage: function () {
			var _this = this

			uni.getImageInfo({
				src: _this.imageSrc,
				success: function success(res) {
					IMG_RATIO = 1 / 1
					if (IMG_RATIO >= 1) {
						IMG_REAL_W = SCREEN_WIDTH
						IMG_REAL_H = SCREEN_WIDTH / IMG_RATIO
					} else {
						IMG_REAL_W = SCREEN_WIDTH * IMG_RATIO
						IMG_REAL_H = SCREEN_WIDTH
					}
					let minRange = IMG_REAL_W > IMG_REAL_H ? IMG_REAL_W : IMG_REAL_H
					INIT_DRAG_POSITION = minRange > INIT_DRAG_POSITION ? INIT_DRAG_POSITION : minRange
					// 根据图片的宽高显示不同的效果   保证图片可以正常显示
					if (IMG_RATIO >= 1) {
						let cutT = Math.ceil((SCREEN_WIDTH / IMG_RATIO - (SCREEN_WIDTH / IMG_RATIO - INIT_DRAG_POSITION)) / 2)
						let cutB = cutT
						let cutL = Math.ceil((SCREEN_WIDTH - SCREEN_WIDTH + INIT_DRAG_POSITION) / 2)
						let cutR = cutL
						_this.setData({
							cropperW: SCREEN_WIDTH,
							cropperH: SCREEN_WIDTH / IMG_RATIO,
							// 初始化left right
							cropperL: Math.ceil((SCREEN_WIDTH - SCREEN_WIDTH) / 2),
							cropperT: Math.ceil((SCREEN_WIDTH - SCREEN_WIDTH / IMG_RATIO) / 2),
							cutL: cutL,
							cutT: cutT,
							cutR: cutR,
							cutB: cutB,
							// 图片缩放值
							imageW: IMG_REAL_W,
							imageH: IMG_REAL_H,
							scaleP: IMG_REAL_W / SCREEN_WIDTH,
							qualityWidth: DRAW_IMAGE_W,
							innerAspectRadio: IMG_RATIO
						})
					} else {
						let cutL = Math.ceil((SCREEN_WIDTH * IMG_RATIO - (SCREEN_WIDTH * IMG_RATIO)) / 2)
						let cutR = cutL
						let cutT = Math.ceil((SCREEN_WIDTH - INIT_DRAG_POSITION) / 2)
						let cutB = cutT
						_this.setData({
							cropperW: SCREEN_WIDTH * IMG_RATIO,
							cropperH: SCREEN_WIDTH,
							// 初始化left right
							cropperL: Math.ceil((SCREEN_WIDTH - SCREEN_WIDTH * IMG_RATIO) / 2),
							cropperT: Math.ceil((SCREEN_WIDTH - SCREEN_WIDTH) / 2),

							cutL: cutL,
							cutT: cutT,
							cutR: cutR,
							cutB: cutB,
							// 图片缩放值
							imageW: IMG_REAL_W,
							imageH: IMG_REAL_H,
							scaleP: IMG_REAL_W / SCREEN_WIDTH,
							qualityWidth: DRAW_IMAGE_W,
							innerAspectRadio: IMG_RATIO
						})
					}
					_this.setData({
						isShowImg: true
					})
					uni.hideLoading()
				}
			})
		},
		// 拖动时候触发的touchStart事件
		contentStartMove(e) {
			PAGE_X = e.touches[0].pageX
			PAGE_Y = e.touches[0].pageY
		},

		// 拖动时候触发的touchMove事件
		contentMoveing(e) {
			var _this = this
			var dragLengthX = (PAGE_X - e.touches[0].pageX) * DRAFG_MOVE_RATIO
			var dragLengthY = (PAGE_Y - e.touches[0].pageY) * DRAFG_MOVE_RATIO
			// 左移
			if (dragLengthX > 0) {
				if (this.cutL - dragLengthX < 0) dragLengthX = this.cutL
			} else {
				if (this.cutR + dragLengthX < 0) dragLengthX = -this.cutR
			}

			if (dragLengthY > 0) {
				if (this.cutT - dragLengthY < 0) dragLengthY = this.cutT
			} else {
				if (this.cutB + dragLengthY < 0) dragLengthY = -this.cutB
			}
			this.setData({
				cutL: this.cutL - dragLengthX,
				cutT: this.cutT - dragLengthY,
				cutR: this.cutR + dragLengthX,
				cutB: this.cutB + dragLengthY
			})

			PAGE_X = e.touches[0].pageX
			PAGE_Y = e.touches[0].pageY
		},

		contentTouchEnd() {

		},

		// 获取图片
		getImageInfo() {
			var _this = this
			uni.showLoading({
				title: '图片生成中...',
			})
			// 将图片写入画布
			const ctx = uni.createCanvasContext('myCanvas')
			ctx.drawImage(_this.imageSrc, 0, 0, IMG_REAL_W, IMG_REAL_H)
			ctx.draw(true, () => {
				// 获取画布要裁剪的位置和宽度   均为百分比 * 画布中图片的宽度    保证了在微信小程序中裁剪的图片模糊  位置不对的问题 canvasT = (_this.cutT / _this.cropperH) * (_this.imageH / pixelRatio)
				var canvasW = ((_this.cropperW - _this.cutL - _this.cutR) / _this.cropperW) * IMG_REAL_W
				var canvasH = ((_this.cropperH - _this.cutT - _this.cutB) / _this.cropperH) * IMG_REAL_H
				var canvasL = (_this.cutL / _this.cropperW) * IMG_REAL_W
				var canvasT = (_this.cutT / _this.cropperH) * IMG_REAL_H
				uni.canvasToTempFilePath({
					x: canvasL,
					y: canvasT,
					width: canvasW,
					height: canvasH,
					destWidth: canvasW,
					destHeight: canvasH,
					quality: 0.5,
					canvasId: 'myCanvas',
					success: function (res) {
						uni.hideLoading()
						let data = { name: 'avatarfile', filePath: res.tempFilePath }
						uploadAvatar(data).then(response => {
							//store.commit('SET_AVATAR', response.imgUrl)
							/*cloud*/
							store.commit('SET_AVATAR', baseUrl + response.imgUrl)
							uni.showToast({ title: "修改成功", icon: 'success' })
							uni.$emit('refresh');
							uni.navigateBack();
						})
					}
				})
			})
		},
		// 设置大小的时候触发的touchStart事件
		dragStart(e) {
			T_PAGE_X = e.touches[0].pageX
			T_PAGE_Y = e.touches[0].pageY
			CUT_L = this.cutL
			CUT_R = this.cutR
			CUT_B = this.cutB
			CUT_T = this.cutT
		},

		// 设置大小的时候触发的touchMove事件
		dragMove(e) {
			var _this = this
			var dragType = e.target.dataset.drag
			switch (dragType) {
				case 'right':
					var dragLength = (T_PAGE_X - e.touches[0].pageX) * DRAFG_MOVE_RATIO
					if (CUT_R + dragLength < 0) dragLength = -CUT_R
					this.setData({
						cutR: CUT_R + dragLength
					})
					break
				case 'left':
					var dragLength = (T_PAGE_X - e.touches[0].pageX) * DRAFG_MOVE_RATIO
					if (CUT_L - dragLength < 0) dragLength = CUT_L
					if ((CUT_L - dragLength) > (this.cropperW - this.cutR)) dragLength = CUT_L - (this.cropperW - this.cutR)
					this.setData({
						cutL: CUT_L - dragLength
					})
					break
				case 'top':
					var dragLength = (T_PAGE_Y - e.touches[0].pageY) * DRAFG_MOVE_RATIO
					if (CUT_T - dragLength < 0) dragLength = CUT_T
					if ((CUT_T - dragLength) > (this.cropperH - this.cutB)) dragLength = CUT_T - (this.cropperH - this.cutB)
					this.setData({
						cutT: CUT_T - dragLength
					})
					break
				case 'bottom':
					var dragLength = (T_PAGE_Y - e.touches[0].pageY) * DRAFG_MOVE_RATIO
					if (CUT_B + dragLength < 0) dragLength = -CUT_B
					this.setData({
						cutB: CUT_B + dragLength
					})
					break
				case 'rightBottom':
					var dragLengthX = (T_PAGE_X - e.touches[0].pageX) * DRAFG_MOVE_RATIO
					var dragLengthY = (T_PAGE_Y - e.touches[0].pageY) * DRAFG_MOVE_RATIO

					if (CUT_B + dragLengthY < 0) dragLengthY = -CUT_B
					if (CUT_R + dragLengthX < 0) dragLengthX = -CUT_R
					let cutB = CUT_B + dragLengthY
					let cutR = CUT_R + dragLengthX

					this.setData({
						cutB: cutB,
						cutR: cutR
					})
					break
				default:
					break
			}
		}
	}
}
</script>

<style>
/* pages/uni-cropper/index.wxss */

.cropper-config {
	padding: 20rpx 40rpx;
}

.cropper-content {
	min-height: 750rpx;
	width: 100%;
}

.uni-corpper {
	position: relative;
	overflow: hidden;
	-webkit-user-select: none;
	-moz-user-select: none;
	-ms-user-select: none;
	user-select: none;
	-webkit-tap-highlight-color: transparent;
	-webkit-touch-callout: none;
	box-sizing: border-box;
}

.uni-corpper-content {
	position: relative;
}

.uni-corpper-content image {
	display: block;
	width: 100%;
	min-width: 0 !important;
	max-width: none !important;
	height: 100%;
	min-height: 0 !important;
	max-height: none !important;
	image-orientation: 0deg !important;
	margin: 0 auto;
}

/* 移动图片效果 */

.uni-cropper-drag-box {
	position: absolute;
	top: 0;
	right: 0;
	bottom: 0;
	left: 0;
	cursor: move;
	background: rgba(0, 0, 0, 0.6);
	z-index: 1;
}

/* 内部的信息 */

.uni-corpper-crop-box {
	position: absolute;
	background: rgba(255, 255, 255, 0.3);
	z-index: 2;
}

.uni-corpper-crop-box .uni-cropper-view-box {
	position: relative;
	display: block;
	width: 100%;
	height: 100%;
	overflow: visible;
	outline: 1rpx solid #69f;
	outline-color: rgba(102, 153, 255, .75)
}

/* 横向虚线 */

.uni-cropper-dashed-h {
	position: absolute;
	top: 33.33333333%;
	left: 0;
	width: 100%;
	height: 33.33333333%;
	border-top: 1rpx dashed rgba(255, 255, 255, 0.5);
	border-bottom: 1rpx dashed rgba(255, 255, 255, 0.5);
}

/* 纵向虚线 */

.uni-cropper-dashed-v {
	position: absolute;
	left: 33.33333333%;
	top: 0;
	width: 33.33333333%;
	height: 100%;
	border-left: 1rpx dashed rgba(255, 255, 255, 0.5);
	border-right: 1rpx dashed rgba(255, 255, 255, 0.5);
}

/* 四个方向的线  为了之后的拖动事件*/

.uni-cropper-line-t {
	position: absolute;
	display: block;
	width: 100%;
	background-color: #69f;
	top: 0;
	left: 0;
	height: 1rpx;
	opacity: 0.1;
	cursor: n-resize;
}

.uni-cropper-line-t::before {
	content: '';
	position: absolute;
	top: 50%;
	right: 0rpx;
	width: 100%;
	-webkit-transform: translate3d(0, -50%, 0);
	transform: translate3d(0, -50%, 0);
	bottom: 0;
	height: 41rpx;
	background: transparent;
	z-index: 11;
}

.uni-cropper-line-r {
	position: absolute;
	display: block;
	background-color: #69f;
	top: 0;
	right: 0rpx;
	width: 1rpx;
	opacity: 0.1;
	height: 100%;
	cursor: e-resize;
}

.uni-cropper-line-r::before {
	content: '';
	position: absolute;
	top: 0;
	left: 50%;
	width: 41rpx;
	-webkit-transform: translate3d(-50%, 0, 0);
	transform: translate3d(-50%, 0, 0);
	bottom: 0;
	height: 100%;
	background: transparent;
	z-index: 11;
}

.uni-cropper-line-b {
	position: absolute;
	display: block;
	width: 100%;
	background-color: #69f;
	bottom: 0;
	left: 0;
	height: 1rpx;
	opacity: 0.1;
	cursor: s-resize;
}

.uni-cropper-line-b::before {
	content: '';
	position: absolute;
	top: 50%;
	right: 0rpx;
	width: 100%;
	-webkit-transform: translate3d(0, -50%, 0);
	transform: translate3d(0, -50%, 0);
	bottom: 0;
	height: 41rpx;
	background: transparent;
	z-index: 11;
}

.uni-cropper-line-l {
	position: absolute;
	display: block;
	background-color: #69f;
	top: 0;
	left: 0;
	width: 1rpx;
	opacity: 0.1;
	height: 100%;
	cursor: w-resize;
}

.uni-cropper-line-l::before {
	content: '';
	position: absolute;
	top: 0;
	left: 50%;
	width: 41rpx;
	-webkit-transform: translate3d(-50%, 0, 0);
	transform: translate3d(-50%, 0, 0);
	bottom: 0;
	height: 100%;
	background: transparent;
	z-index: 11;
}

.uni-cropper-point {
	width: 5rpx;
	height: 5rpx;
	background-color: #69f;
	opacity: .75;
	position: absolute;
	z-index: 3;
}

.point-t {
	top: -3rpx;
	left: 50%;
	margin-left: -3rpx;
	cursor: n-resize;
}

.point-tr {
	top: -3rpx;
	left: 100%;
	margin-left: -3rpx;
	cursor: n-resize;
}

.point-r {
	top: 50%;
	left: 100%;
	margin-left: -3rpx;
	margin-top: -3rpx;
	cursor: n-resize;
}

.point-rb {
	left: 100%;
	top: 100%;
	-webkit-transform: translate3d(-50%, -50%, 0);
	transform: translate3d(-50%, -50%, 0);
	cursor: n-resize;
	width: 36rpx;
	height: 36rpx;
	background-color: #69f;
	position: absolute;
	z-index: 1112;
	opacity: 1;
}

.point-b {
	left: 50%;
	top: 100%;
	margin-left: -3rpx;
	margin-top: -3rpx;
	cursor: n-resize;
}

.point-bl {
	left: 0%;
	top: 100%;
	margin-left: -3rpx;
	margin-top: -3rpx;
	cursor: n-resize;
}

.point-l {
	left: 0%;
	top: 50%;
	margin-left: -3rpx;
	margin-top: -3rpx;
	cursor: n-resize;
}

.point-lt {
	left: 0%;
	top: 0%;
	margin-left: -3rpx;
	margin-top: -3rpx;
	cursor: n-resize;
}

/* 裁剪框预览内容 */

.uni-cropper-viewer {
	position: relative;
	width: 100%;
	height: 100%;
	overflow: hidden;
}

.uni-cropper-viewer image {
	position: absolute;
	z-index: 2;
}
</style>
