<template>
    <div>
        <cheader :title="sortName" class="list-header"></cheader>
        <filter-box :val="order" :filter="filterConfig" v-if="enableOrder"></filter-box>
        <product-list :data="productList" :state="listState" class="list-items"></product-list>
        <shopping-bag :cart-count="cartCount" v-if="isApp"></shopping-bag>
    </div>
</template>
<script>
    import $ from 'jquery';
    import yoho from 'yoho';
    import Vue from 'vue';
    import lazyload from 'vue-lazyload';
    import infinitScroll from 'vue-infinite-scroll';
    import qs from 'yoho-qs/parse';
    import bus from 'common/vue-bus';
    import tip from 'common/tip';
    import cheader from 'component/header.vue';
    import ProductList from 'component/product/list.vue';
    import ShoppingBag from 'component/product/shopping-bag.vue';
    import FilterBox from 'component/product/filter/index.vue';

    let locationQuery = qs(decodeURIComponent(location.search.replace(/^\?/, '')));

    Vue.use(lazyload, { preLoad: 3 });
    Vue.use(infinitScroll);


    export default {
        data: function() {
            return {
                isApp: yoho.isApp,
                isiOS: yoho.isiOS,
                sortName: locationQuery.title || locationQuery.sort_name, // 优先使用 title
                orderConfig: [],
                filterConfig: null,

                // query
                url: '/product/list.json',
                order: '',
                filter: {},
                page: 0, // 未搜索 page=0; 全部加载完 page = totalPage; 无数据: page !=0 && productList.length=0
                totalPage: null,

                // 产品列表
                productList: [],

                // state
                inSearching: false, // 请求中
                enableOrder: false,
                cartCount: 0
            };
        },
        computed: {
            empty: function() {
                return this.page !== 0 && !this.productList.length;
            },
            listState: function() {
                let state = 1; // 0: 全部加载完  1: 正在加载

                if (!this.page) {
                    return;
                }

                if (!this.productList.length) {
                    return -1;
                } else if (this.page === this.totalPage) {
                    return 0;
                } else if (this.inSearching) {
                    return 1;
                }

                return state;
            }
        },
        components: {
            cheader,
            ProductList,
            ShoppingBag,
            FilterBox
        },
        methods: {
            search: function() {
                const nextPage = this.page + 1;

                if (this.inSearching) {
                    return;
                }

                // page = 0, 始终执行搜索
                if (this.page && nextPage > this.totalPage) {
                    return;
                }

                this.inSearching = true;
                return $.get(this.url, Object.assign({
                    order: this.order,
                    page: nextPage
                }, locationQuery, this.filter))
                    .done(res => {
                        if (res.data) {
                            this.page = res.data.page;
                            this.totalPage = res.data.page_total;
                            this.productList = this.productList.concat(res.data.product_list);

                            if (!this.filterConfig) {
                                this.filterConfig = res.data.filter;
                            }
                        }
                    })
                    .fail(() => {  // eslint-disable-line
                        tip('网络出错~');
                    })
                    .always(() => {
                        this.inSearching = false;

                        // 完成后删除服务端渲染的元素
                        setTimeout(()=> {
                            $('#ssr').remove();
                        }, 500);
                    });
            },

            openFilter() {
                this.$refs.filter.isVisible = true;
            },

            /**
             *  清空数据（page=0） 重新搜索
             */
            research: function() {
                this.page = 0;
                this.productList = [];
                this.search();
            },

            refreshCart: function() {
                $.get('/product/cart-count.json').then(result=> {
                    if (result.code === 200) {
                        this.cartCount = result.data.cart_goods_count;
                    }
                });
            }
        },
        watch: {
            /* order 和 filter 改变 都会触发 重新搜索 */
            order: function() {
                this.research();
            },
            filter: function() {
                this.research();
            }
        },
        created: function() {
            const self = this;


            bus.$on('list.paging', function() {
                self.search();
            });

            bus.$on('order.change', function({val}) {
                self.order = val;
            });

            bus.$on('filter.change', function({val}) {
                self.filter = val;
            });

            this.search()
                .then(()=>{
                    if (self.productList.length) {
                        self.enableOrder = true;
                    }
                });

            // 读取购物车数量
            if (this.isApp) {
                this.refreshCart();
                bus.$on('app.shoppingcart.refresh', this.refreshCart);
            }

        }
    };

</script>
<style>
    .list-header {
        background-color: white;
    }

    .list-items {
        padding-top: 111px;
    }
</style>