<template>
	<view :class="[styleType === 'text'?'segmented-control--text' : 'segmented-control--button' ]"
		:style="{ borderColor: styleType === 'text' ? '' : activeColor }" class="segmented-control">
		<view v-for="(item, index) in values" :class="[styleType === 'text' ? '' : 'segmented-control__item--button',
					index === currentIndex && styleType === 'button' ? 'segmented-control__item--button--active' : '',
					index === 0 && styleType === 'button' ? 'segmented-control__item--button--first' : '',
					index === values.length - 1 && styleType === 'button' ? 'segmented-control__item--button--last':'']" :key="index" :style="{backgroundColor: index === currentIndex && styleType === 'button' ? activeColor : styleType === 'button' ?inActiveColor:'transparent', borderColor: index === currentIndex && styleType === 'text' || styleType === 'button' ? activeColor : inActiveColor}" class="segmented-control__item" @click="_onClick(index)">
			<view>
				<text
					:style="index===currentIndex?{color : styleType === 'text' ? activeColor : '#fff'}:{color : styleType === 'text' ?'#000' : activeColor}"
					class="segmented-control__text"
					:class="styleType === 'text' && index === currentIndex ? 'segmented-control__item--text': ''">{{ item }}</text>
			</view>

		</view>
	</view>
</template>

<script>
	/**
	 * SegmentedControl 分段器
	 * @description 用作不同视图的显示
	 * @tutorial https://ext.dcloud.net.cn/plugin?id=54
	 * @property {Number} current 当前选中的tab索引值，从0计数
	 * @property {String} styleType = [button|text] 分段器样式类型
	 * 	@value button 按钮类型
	 * 	@value text 文字类型
	 * @property {String} activeColor 选中的标签背景色与边框颜色
	 * @property {String} inActiveColor 未选中的标签背景色与边框颜色
	 * @property {Array} values 选项数组
	 * @event {Function} clickItem 组件触发点击事件时触发，e={currentIndex}
	 */

	export default {
		name: 'UniSegmentedControl',
		emits: ['clickItem'],
		props: {
			current: {
				type: Number,
				default: 0
			},
			values: {
				type: Array,
				default () {
					return []
				}
			},
			activeColor: {
				type: String,
				default: '#2979FF'
			},
			inActiveColor: {
				type: String,
				default: 'transparent'
			},
			styleType: {
				type: String,
				default: 'button'
			}
		},
		data() {
			return {
				currentIndex: 0
			}
		},
		watch: {
			current(val) {
				if (val !== this.currentIndex) {
					this.currentIndex = val
				}
			}
		},
		computed: {
			getTextStyle() {
				return (index) => {
					let style = {};
					if (index === this.currentIndex) {
						style.color = this.styleType === 'text' ? this.activeColor : '#fff';
					} else {
						style.color = this.styleType === 'text' ?
							'#000' : this.activeColor;
					}
					return style;
				}
			},
			computedBackgroundClass() {
				return index => [this.styleType === 'text' ? '' : 'segmented-control__item--button',
					index === this.currentIndex && this.styleType === 'button' ? 'segmented-control__item--button--active' : '',
					index === 0 && this.styleType === 'button' ? 'segmented-control__item--button--first' : '',
					index === this.values.length - 1 && this.styleType === 'button' ? 'segmented-control__item--button--last' :
					''
				]
			},
			computedBackgroundStyle() {
				return index => {
					return {
						backgroundColor: index === this.currentIndex && this.styleType === 'button' ? this.activeColor : this
							.styleType === 'button' ? this.inActiveColor : 'transparent',
						borderColor: index === this.currentIndex && this.styleType === 'text' || this.styleType === 'button' ? this
							.activeColor : this.inActiveColor
					}
				}
			}
		},
		created() {
			this.currentIndex = this.current
		},
		methods: {
			_onClick(index) {
				if (this.currentIndex !== index) {
					this.currentIndex = index
					this.$emit('clickItem', {
						currentIndex: index
					})
				}
			}
		}
	}
</script>

<style lang="scss" scoped>
	.segmented-control {
		/* #ifndef APP-NVUE */
		display: flex;
		box-sizing: border-box;
		/* #endif */
		flex-direction: row;
		height: 36px;
		overflow: hidden;
		/* #ifdef H5 */
		cursor: pointer;
		/* #endif */
	}

	.segmented-control__item {
		/* #ifndef APP-NVUE */
		display: inline-flex;
		box-sizing: border-box;
		/* #endif */
		position: relative;
		flex: 1;
		justify-content: center;
		align-items: center;
	}

	.segmented-control__item--button {
		border-style: solid;
		border-top-width: 1px;
		border-bottom-width: 1px;
		border-right-width: 1px;
		border-left-width: 0;
	}

	.segmented-control__item--button--first {
		border-left-width: 1px;
		border-top-left-radius: 5px;
		border-bottom-left-radius: 5px;
	}

	.segmented-control__item--button--last {
		border-top-right-radius: 5px;
		border-bottom-right-radius: 5px;
	}

	.segmented-control__item--text {
		border-bottom-style: solid;
		border-bottom-width: 2px;
		padding: 6px 0;
	}

	.segmented-control__text {
		font-size: 14px;
		line-height: 20px;
		text-align: center;
	}
</style>