// Components
import { VFadeTransition } from '../transitions'
import VExpansionPanel from './VExpansionPanel'
import VIcon from '../VIcon'

// Mixins
import Colorable from '../../mixins/colorable'
import { inject as RegistrableInject } from '../../mixins/registrable'

// Directives
import ripple from '../../directives/ripple'

// Utilities
import { getSlot } from '../../util/helpers'
import mixins, { ExtractVue } from '../../util/mixins'

// Types
import Vue, { VNode, VueConstructor } from 'vue'

const baseMixins = mixins(
  Colorable,
  RegistrableInject<'expansionPanel', VueConstructor<Vue>>('expansionPanel', 'v-expansion-panel-header', 'v-expansion-panel')
)

interface options extends ExtractVue<typeof baseMixins> {
  $el: HTMLElement
  expansionPanel: InstanceType<typeof VExpansionPanel>
}

export default baseMixins.extend<options>().extend({
  name: 'v-expansion-panel-header',

  directives: { ripple },

  props: {
    disableIconRotate: Boolean,
    expandIcon: {
      type: String,
      default: '$expand',
    },
    hideActions: Boolean,
    ripple: {
      type: [Boolean, Object],
      default: false,
    },
  },

  data: () => ({
    hasMousedown: false,
  }),

  computed: {
    classes (): object {
      return {
        'v-expansion-panel-header--active': this.isActive,
        'v-expansion-panel-header--mousedown': this.hasMousedown,
      }
    },
    isActive (): boolean {
      return this.expansionPanel.isActive
    },
    isDisabled (): boolean {
      return this.expansionPanel.isDisabled
    },
    isReadonly (): boolean {
      return this.expansionPanel.isReadonly
    },
  },

  created () {
    this.expansionPanel.registerHeader(this)
  },

  beforeDestroy () {
    this.expansionPanel.unregisterHeader()
  },

  methods: {
    onClick (e: MouseEvent) {
      this.$emit('click', e)
    },
    genIcon () {
      const icon = getSlot(this, 'actions') ||
        [this.$createElement(VIcon, this.expandIcon)]

      return this.$createElement(VFadeTransition, [
        this.$createElement('div', {
          staticClass: 'v-expansion-panel-header__icon',
          class: {
            'v-expansion-panel-header__icon--disable-rotate': this.disableIconRotate,
          },
          directives: [{
            name: 'show',
            value: !this.isDisabled,
          }],
        }, icon),
      ])
    },
  },

  render (h): VNode {
    return h('button', this.setBackgroundColor(this.color, {
      staticClass: 'v-expansion-panel-header',
      class: this.classes,
      attrs: {
        tabindex: this.isDisabled ? -1 : null,
        type: 'button',
      },
      directives: [{
        name: 'ripple',
        value: this.ripple,
      }],
      on: {
        ...this.$listeners,
        click: this.onClick,
        mousedown: () => (this.hasMousedown = true),
        mouseup: () => (this.hasMousedown = false),
      },
    }), [
      getSlot(this, 'default', { open: this.isActive }, true),
      this.hideActions || this.genIcon(),
    ])
  },
})