<template>
  <div class="material-input__component" :class="computedClasses">
    <div :class="{iconClass:icon}">
      <i class="el-input__icon material-input__icon" :class="['el-icon-' + icon]" v-if="icon"></i>
      <input v-if="type === 'email'" type="email" class="material-input" :name="name" :placeholder="fillPlaceHolder" v-model="currentValue"
        :readonly="readonly" :disabled="disabled" :autoComplete="autoComplete" :required="required" @focus="handleMdFocus"
        @blur="handleMdBlur" @input="handleModelInput">
      <input v-if="type === 'url'" type="url" class="material-input" :name="name" :placeholder="fillPlaceHolder" v-model="currentValue"
        :readonly="readonly" :disabled="disabled" :autoComplete="autoComplete" :required="required" @focus="handleMdFocus"
        @blur="handleMdBlur" @input="handleModelInput">
      <input v-if="type === 'number'" type="number" class="material-input" :name="name" :placeholder="fillPlaceHolder" v-model="currentValue"
        :step="step" :readonly="readonly" :disabled="disabled" :autoComplete="autoComplete" :max="max" :min="min" :minlength="minlength"
        :maxlength="maxlength" :required="required" @focus="handleMdFocus" @blur="handleMdBlur" @input="handleModelInput">
      <input v-if="type === 'password'" type="password" class="material-input" :name="name" :placeholder="fillPlaceHolder" v-model="currentValue"
        :readonly="readonly" :disabled="disabled" :autoComplete="autoComplete" :max="max" :min="min" :required="required" @focus="handleMdFocus"
        @blur="handleMdBlur" @input="handleModelInput">
      <input v-if="type === 'tel'" type="tel" class="material-input" :name="name" :placeholder="fillPlaceHolder" v-model="currentValue"
        :readonly="readonly" :disabled="disabled" :autoComplete="autoComplete" :required="required" @focus="handleMdFocus"
        @blur="handleMdBlur" @input="handleModelInput">
      <input v-if="type === 'text'" type="text" class="material-input" :name="name" :placeholder="fillPlaceHolder" v-model="currentValue"
        :readonly="readonly" :disabled="disabled" :autoComplete="autoComplete" :minlength="minlength" :maxlength="maxlength"
        :required="required" @focus="handleMdFocus" @blur="handleMdBlur" @input="handleModelInput">
      <span class="material-input-bar"></span>
      <label class="material-label">
        <slot></slot>
      </label>
    </div>
  </div>
</template>

<script>
// source:https://github.com/wemake-services/vue-material-input/blob/master/src/components/MaterialInput.vue

export default {
  name: 'md-input',
  props: {
    icon: String,
    name: String,
    type: {
      type: String,
      default: 'text'
    },
    value: [String, Number],
    placeholder: String,
    readonly: Boolean,
    disabled: Boolean,
    min: String,
    max: String,
    step: String,
    minlength: Number,
    maxlength: Number,
    required: {
      type: Boolean,
      default: true
    },
    autoComplete: {
      type: String,
      default: 'off'
    },
    validateEvent: {
      type: Boolean,
      default: true
    }
  },
  computed: {
    computedClasses() {
      return {
        'material--active': this.focus,
        'material--disabled': this.disabled,
        'material--raised': Boolean(this.focus || this.currentValue) // has value
      }
    }
  },
  watch: {
    value(newValue) {
      this.currentValue = newValue
    }
  },
  data() {
    return {
      currentValue: this.value,
      focus: false,
      fillPlaceHolder: null
    }
  },
  methods: {
    handleModelInput(event) {
      const value = event.target.value
      this.$emit('input', value)
      if (this.$parent.$options.componentName === 'ElFormItem') {
        if (this.validateEvent) {
          this.$parent.$emit('el.form.change', [value])
        }
      }
      this.$emit('change', value)
    },
    handleMdFocus(event) {
      this.focus = true
      this.$emit('focus', event)
      if (this.placeholder && this.placeholder !== '') {
        this.fillPlaceHolder = this.placeholder
      }
    },
    handleMdBlur(event) {
      this.focus = false
      this.$emit('blur', event)
      this.fillPlaceHolder = null
      if (this.$parent.$options.componentName === 'ElFormItem') {
        if (this.validateEvent) {
          this.$parent.$emit('el.form.blur', [this.currentValue])
        }
      }
    }
  }
}
</script>

<style rel="stylesheet/scss" lang="scss" scoped>
  // Fonts:
  $font-size-base: 16px;
  $font-size-small: 18px;
  $font-size-smallest: 12px;
  $font-weight-normal: normal;
  $font-weight-bold: bold;
  $apixel: 1px;
  // Utils
  $spacer: 12px;
  $transition: 0.2s ease all;
  $index: 0px;
  $index-has-icon: 30px;
  // Theme:
  $color-white: white;
  $color-grey: #9E9E9E;
  $color-grey-light: #E0E0E0;
  $color-blue: #2196F3;
  $color-red: #F44336;
  $color-black: black;
  // Base clases:
  %base-bar-pseudo {
    content: '';
    height: 1px;
    width: 0;
    bottom: 0;
    position: absolute;
    transition: $transition;
  }

  // Mixins:
  @mixin slided-top() {
    top: - ($font-size-base + $spacer);
    left: 0;
    font-size: $font-size-base;
    font-weight: $font-weight-bold;
  }

  // Component:
  .material-input__component {
    margin-top: 36px;
    position: relative;
    * {
      box-sizing: border-box;
    }
    .iconClass {
      .material-input__icon {
        position: absolute;
        left: 0;
        color: $color-blue;
        top: $spacer;
        width: $index-has-icon;
        height: $font-size-base;
        font-size: $font-size-base;
        font-weight: $font-weight-normal;
        pointer-events: none;
      }
      .material-label {
        left: $index-has-icon;
      }
      .material-input {
        text-indent: $index-has-icon;
      }
    }
    .material-input {
      font-size: $font-size-base;
      padding: $spacer $spacer $spacer - $apixel * 10 $spacer / 2;
      display: block;
      width: 100%;
      border: none;
      line-height: 1;
      border-radius: 0;
      &:focus {
        outline: none;
        border: none;
        border-bottom: 1px solid transparent; // fixes the height issue
      }
    }
    .material-label {
      font-weight: $font-weight-normal;
      position: absolute;
      pointer-events: none;
      left: $index;
      top: 0;
      transition: $transition;
      font-size: $font-size-small;
    }
    .material-input-bar {
      position: relative;
      display: block;
      width: 100%;
      &:before {
        @extend %base-bar-pseudo;
        left: 50%;
      }
      &:after {
        @extend %base-bar-pseudo;
        right: 50%;
      }
    }
    // Disabled state:
    &.material--disabled {
      .material-input {
        border-bottom-style: dashed;
      }
    }
    // Raised state:
    &.material--raised {
      .material-label {
        @include slided-top();
      }
    }
    // Active state:
    &.material--active {
      .material-input-bar {
        &:before,
        &:after {
          width: 50%;
        }
      }
    }
  }

  .material-input__component {
    background: $color-white;
    .material-input {
      background: none;
      color: $color-black;
      text-indent: $index;
      border-bottom: 1px solid $color-grey-light;
    }
    .material-label {
      color: $color-grey;
    }
    .material-input-bar {
      &:before,
      &:after {
        background: $color-blue;
      }
    }
    // Active state:
    &.material--active {
      .material-label {
        color: $color-blue;
      }
    }
    // Errors:
    &.material--has-errors {
      &.material--active .material-label {
        color: $color-red;
      }
      .material-input-bar {
        &:before,
        &:after {
          background: transparent;
        }
      }
    }
  }
</style>
