<template>
	<view class="popup-mask" v-if="visible" @click.self="close">
		<view class="popup-content">
			<view class="popup-title">优惠券二维码</view>
			<view class="qrcode-area">
				<canvas canvas-id="qrcode" id="qrcode" class="qrcode-canvas"></canvas>
				<text class="coupon-code">{{ code }}</text>
			</view>
			<view class="popup-tip">请将二维码出示给商户扫码核销</view>
			<button class="btn-close" @click="close">关闭</button>
		</view>
	</view>
</template>

<script>
	import UQRCode from 'uqrcodejs'

	export default {
		name: 'QrcodePopup',
		props: {
			visible: { type: Boolean, default: false },
			code: { type: String, default: '' }
		},
		emits: ['close'],
		watch: {
			visible(val) {
				if (val && this.code) {
					this.$nextTick(() => {
						setTimeout(() => this.drawQrcode(), 100)
					})
				}
			}
		},
		methods: {
			close() {
				this.$emit('close')
			},
			drawQrcode() {
				const qr = new UQRCode()
				qr.data = this.code
				qr.size = 200
				qr.make()

				const ctx = uni.createCanvasContext('qrcode', this)
				// 白色背景
				ctx.setFillStyle('#ffffff')
				ctx.fillRect(0, 0, 200, 200)

				// 绘制二维码模块
				const tileSize = qr.moduleSize
				for (let row = 0; row < qr.moduleCount; row++) {
					for (let col = 0; col < qr.moduleCount; col++) {
						if (qr.modules[row][col]) {
							ctx.setFillStyle('#333333')
						} else {
							ctx.setFillStyle('#ffffff')
						}
						const x = qr.paintingX + col * tileSize
						const y = qr.paintingY + row * tileSize
						ctx.fillRect(x, y, tileSize, tileSize)
					}
				}
				ctx.draw()
			}
		}
	}
</script>

<style scoped>
	.popup-mask {
		position: fixed;
		top: 0; left: 0; right: 0; bottom: 0;
		background: rgba(0, 0, 0, 0.5);
		display: flex;
		align-items: center;
		justify-content: center;
		z-index: 999;
	}
	.popup-content {
		background: #fff;
		border-radius: 24rpx;
		padding: 40rpx;
		width: 560rpx;
		text-align: center;
	}
	.popup-title {
		font-size: 34rpx;
		font-weight: bold;
		color: #333;
		margin-bottom: 30rpx;
	}
	.qrcode-area {
		display: flex;
		flex-direction: column;
		align-items: center;
		margin-bottom: 20rpx;
	}
	.qrcode-canvas {
		width: 400rpx;
		height: 400rpx;
	}
	.coupon-code {
		font-size: 28rpx;
		color: #666;
		margin-top: 16rpx;
		letter-spacing: 4rpx;
	}
	.popup-tip {
		font-size: 24rpx;
		color: #999;
		margin-bottom: 30rpx;
	}
	.btn-close {
		background: #f5f5f5;
		color: #666;
		border-radius: 8rpx;
		font-size: 28rpx;
	}
</style>
