<script lang="ts">
    import { computed, defineComponent, onMounted, ref, unref, watch } from 'vue'
    import { TreeSelect } from 'ant-design-vue'
    import { isArray, isFunction } from '/@/utils/is'
    import { get } from 'lodash-es'
    import { propTypes } from '/@/utils/propTypes'
    import { LoadingOutlined } from '@ant-design/icons-vue'

    export default defineComponent({
        name: 'ApiTreeSelect',
        components: { ATreeSelect: TreeSelect, LoadingOutlined },
        props: {
            api: { type: Function as PropType<(arg?: Recordable) => Promise<Recordable>> },
            params: { type: Object },
            immediate: { type: Boolean, default: true },
            resultField: propTypes.string.def(''),
        },
        emits: ['options-change', 'change'],
        setup(props, { attrs, emit }) {
            const treeData = ref<Recordable[]>([])
            const isFirstLoaded = ref<Boolean>(false)
            const loading = ref(false)
            const getAttrs = computed(() => {
                return {
                    ...(props.api ? { treeData: unref(treeData) } : {}),
                    ...attrs,
                }
            })

            function handleChange(...args) {
                emit('change', ...args)
            }

            watch(
                () => props.params,
                () => {
                    !unref(isFirstLoaded) && fetch()
                },
                { deep: true },
            )

            watch(
                () => props.immediate,
                (v) => {
                    v && !isFirstLoaded.value && fetch()
                },
            )

            onMounted(() => {
                props.immediate && fetch()
            })

            async function fetch() {
                const { api } = props
                if (!api || !isFunction(api)) return
                loading.value = true
                treeData.value = []
                let result
                try {
                    result = await api(props.params)
                } catch (e) {
                    console.error(e)
                }
                loading.value = false
                if (!result) return
                if (!isArray(result)) {
                    result = get(result, props.resultField)
                }
                treeData.value = (result as Recordable[]) || []
                isFirstLoaded.value = true
                emit('options-change', treeData.value)
            }
            return { getAttrs, loading, handleChange }
        },
    })
</script>

<template>
    <ATreeSelect v-bind="getAttrs" @change="handleChange">
        <template #[item]="data" v-for="item in Object.keys($slots)">
            <slot :name="item" v-bind="data || {}"></slot>
        </template>
        <template #suffixIcon v-if="loading">
            <LoadingOutlined spin />
        </template>
    </ATreeSelect>
</template>
