<template>
  <view
    v-if="isShow"
    ref="ani"
    class="uni-transition"
    :class="[ani.in]"
    :style="'transform:' + transform + ';' + stylesObject"
    @click="change"
  >
    <slot />
  </view>
</template>

<script>
// #ifdef APP-NVUE
const animation = uni.requireNativePlugin("animation");
// #endif
/**
 * Transition 过渡动画
 * @description 简单过渡动画组件
 * @tutorial https://ext.dcloud.net.cn/plugin?id=985
 * @property {Boolean} show = [false|true] 控制组件显示或隐藏
 * @property {Array} modeClass = [fade|slide-top|slide-right|slide-bottom|slide-left|zoom-in|zoom-out] 过渡动画类型
 *  @value fade 渐隐渐出过渡
 *  @value slide-top 由上至下过渡
 *  @value slide-right 由右至左过渡
 *  @value slide-bottom 由下至上过渡
 *  @value slide-left 由左至右过渡
 *  @value zoom-in 由小到大过渡
 *  @value zoom-out 由大到小过渡
 * @property {Number} duration 过渡动画持续时间
 * @property {Object} styles 组件样式，同 css 样式，注意带’-‘连接符的属性需要使用小驼峰写法如：`backgroundColor:red`
 */
export default {
  name: "UniTransition",
  props: {
    show: {
      type: Boolean,
      default: false
    },
    modeClass: {
      type: Array,
      default() {
        return [];
      }
    },
    duration: {
      type: Number,
      default: 300
    },
    styles: {
      type: Object,
      default() {
        return {};
      }
    }
  },
  data() {
    return {
      isShow: false,
      transform: "",
      ani: { in: "", active: "" }
    };
  },
  computed: {
    stylesObject() {
      let styles = {
        ...this.styles,
        "transition-duration": this.duration / 1000 + "s"
      };
      let transfrom = "";
      for (let i in styles) {
        let line = this.toLine(i);
        transfrom += line + ":" + styles[i] + ";";
      }
      return transfrom;
    }
  },
  watch: {
    show: {
      handler(newVal) {
        if (newVal) {
          this.open();
        } else {
          this.close();
        }
      },
      immediate: true
    }
  },
  created() {
    // this.timer = null
    // this.nextTick = (time = 50) => new Promise(resolve => {
    // 	clearTimeout(this.timer)
    // 	this.timer = setTimeout(resolve, time)
    // 	return this.timer
    // });
  },
  methods: {
    change() {
      this.$emit("click", {
        detail: this.isShow
      });
    },
    open() {
      clearTimeout(this.timer);
      this.isShow = true;
      this.transform = "";
      this.ani.in = "";
      for (let i in this.getTranfrom(false)) {
        if (i === "opacity") {
          this.ani.in = "fade-in";
        } else {
          this.transform += `${this.getTranfrom(false)[i]} `;
        }
      }
      this.$nextTick(() => {
        let timeout = setTimeout(() => {
          clearTimeout(timeout);
          timeout = null;
          this._animation(true);
        }, 50);
      });
    },
    close() {
      clearTimeout(this.timer);
      this._animation(false);
    },
    _animation(type) {
      let styles = this.getTranfrom(type);
      // #ifdef APP-NVUE
      if (!this.$refs["ani"]) return;
      animation.transition(
        this.$refs["ani"].ref,
        {
          styles,
          duration: this.duration, //ms
          timingFunction: "ease",
          needLayout: false,
          delay: 0 //ms
        },
        () => {
          if (!type) {
            this.isShow = false;
          }
          this.$emit("change", {
            detail: this.isShow
          });
        }
      );
      // #endif
      // #ifndef APP-NVUE
      this.transform = "";
      for (let i in styles) {
        if (i === "opacity") {
          this.ani.in = `fade-${type ? "out" : "in"}`;
        } else {
          this.transform += `${styles[i]} `;
        }
      }
      this.timer = setTimeout(() => {
        if (!type) {
          this.isShow = false;
        }
        this.$emit("change", {
          detail: this.isShow
        });
      }, this.duration);
      // #endif
    },
    getTranfrom(type) {
      let styles = {
        transform: ""
      };
      this.modeClass.forEach(mode => {
        switch (mode) {
          case "fade":
            styles.opacity = type ? 1 : 0;
            break;
          case "slide-top":
            styles.transform += `translateY(${type ? "0" : "-100%"}) `;
            break;
          case "slide-right":
            styles.transform += `translateX(${type ? "0" : "100%"}) `;
            break;
          case "slide-bottom":
            styles.transform += `translateY(${type ? "0" : "100%"}) `;
            break;
          case "slide-left":
            styles.transform += `translateX(${type ? "0" : "-100%"}) `;
            break;
          case "zoom-in":
            styles.transform += `scale(${type ? 1 : 0.8}) `;
            break;
          case "zoom-out":
            styles.transform += `scale(${type ? 1 : 1.2}) `;
            break;
        }
      });
      return styles;
    },
    _modeClassArr(type) {
      let mode = this.modeClass;
      if (typeof mode !== "string") {
        let modestr = "";
        mode.forEach(item => {
          modestr += item + "-" + type + ",";
        });
        return modestr.substr(0, modestr.length - 1);
      } else {
        return mode + "-" + type;
      }
    },
    // getEl(el) {
    // 	console.log(el || el.ref || null);
    // 	return el || el.ref || null
    // },
    toLine(name) {
      return name.replace(/([A-Z])/g, "-$1").toLowerCase();
    }
  }
};
</script>

<style>
.uni-transition {
  transition-timing-function: ease;
  transition-duration: 0.3s;
  transition-property: transform, opacity;
}

.fade-in {
  opacity: 0;
}

.fade-active {
  opacity: 1;
}

.slide-top-in {
  /* transition-property: transform, opacity; */
  transform: translateY(-100%);
}

.slide-top-active {
  transform: translateY(0);
  /* opacity: 1; */
}

.slide-right-in {
  transform: translateX(100%);
}

.slide-right-active {
  transform: translateX(0);
}

.slide-bottom-in {
  transform: translateY(100%);
}

.slide-bottom-active {
  transform: translateY(0);
}

.slide-left-in {
  transform: translateX(-100%);
}

.slide-left-active {
  transform: translateX(0);
  opacity: 1;
}

.zoom-in-in {
  transform: scale(0.8);
}

.zoom-out-active {
  transform: scale(1);
}

.zoom-out-in {
  transform: scale(1.2);
}
</style>
