<template>
	<view class="ezy-xuexi-page3">
		<view class="icon-title-navBar-box">
			<text class="nav-bar-title">学习</text>
		</view>
		<!-- 吸顶单元标题 -->
		<view
			v-if="currentStickyTitle"
			class="item-dy-box item-fixed"
		>
			<view class="dy-left-box">L{{ currentStickyDengjiId }}</view>
			<view class="dy-right-box">
				<view class="right-content">
					<view class="dy-name">{{ currentStickyTitle }}</view>
					<view>{{ currentStickyIntro }}</view>
				</view>
			</view>
		</view>

		<!-- 滚动区域 -->
		<scroll-view
			v-if="existData"
			class="ezy-page-body xuexi-page-body"
			scroll-y
			:scroll-top="scrollTop"
			@scroll="handleScroll"
		>
			<view class="xxjl-card-box-padding">
				<view class="xxjl-card-box">
					<!-- 显示内容 -->
					<view class="card-body-box">
						<img :src="banbenInfo.cover" />
						<view class="body-right">
							<view class="right-name">{{ banbenInfo.chanpinName }}</view>
							<view>等级：{{banbenInfo.dengjiName}}</view>
							<view>版本：{{banbenInfo.name}}</view>
							<view>单元：{{banbenInfo.curDanyuanName}}</view>
							<view>课程：{{banbenInfo.curKechengName}}</view>
						</view>
					</view>
					<view class="card-progress-box">
						<view class="xx-progress-box">
							<view>学习进度</view>
							<progress :percent="curProcess" class="xx-progress" stroke-width="20"
								backgroundColor="#3c7dfd" activeColor="#ffd11c" />
						</view>
						<ezyActiveVue class="ezy-btn-active jxxx-btn" @aclick="handlePlay(banbenInfo,'jixu')"></ezyActiveVue>
					</view>
				</view>
			</view>

			<view class="xx-item-list">
				<!-- <view class="xx-item-title">— 以下为当前等级课程目录 —</view> -->

				<view v-for="(danyuanItem, index) in danyuanList" :key="danyuanItem.danyuanId">

					<!-- 单元标题（带唯一ID，用于位置查询） -->
					<view class="xx-item-title" :id="`title-${danyuanItem.danyuanId}`">
						— {{ danyuanItem.danyuanName }} {{ danyuanItem.danyuanIntro }} —
					</view>

					<!-- 节列表 -->
					<ezyActiveVue
						class="ezy-list-item-active xx-item-box"
						v-for="jieItem in danyuanItem.jieList"
						:key="jieItem.jieId"
						@aclick="handlePlay(jieItem,'play')"
					>
						<view
							class="xx-item-status"
							:class="jieItem.wanchengFlag == 1 ? 'completed-status' : 'uncompleted-status'"
						></view>
						<img :src="jieItem.cover" />
						<view class="xx-text-box">
							<view>{{ jieItem.jieName }}</view>
							<view>{{ jieItem.jieIntro }}</view>
						</view>
						<view class="xx-item-btn"></view>
					</ezyActiveVue>
				</view>

				<view class="xx-item-title">本级别最后一单元啦~</view>
				<view class="xx-more-btn" @click="moreBtn"></view>
			</view>
		</scroll-view>
		<!-- 回到顶部 -->
		<view v-if="currentStickyTitle" class="go-top-btn" @click="goTopBtn"></view>

		<!-- 无数据占位 -->
		<view v-if="!existData" class="ezy-page-body xuexi-page-body"></view>

		<!-- 弹窗组件 -->
		<danyuanInfoVue ref="dyRef" v-if="isShow" @close="isShow = false"></danyuanInfoVue>

		<!-- 底部 tabBar -->
		<custom-tab-bar :show="true" :current-index="currentTabIndex" />
	</view>
</template>

<script>
	import ezyActiveVue from "@/components/ezyActive/ezyActive.vue";
	import CustomTabBar from '@/components/custom-tabbar/index.vue';
	import cacheManager from "@/utils/cacheManager.js";
	import {
		shuxueChanpinBanbenInfo,
		shuxueSave
	} from "@/api/chanpinneirong.js"
	import {
		onLoad,
		onShow,
		onHide,
		onUnload
	} from "@dcloudio/uni-app"
	import danyuanInfoVue from '@/pages/xinshuxue/components/danyuanInfo.vue';
	import {
		toast
	} from '../../utils/common';
  import {updateXuexiProcess} from "./useNeirongShuxue"
	export default {
		data() {
			return {
				canExitApp: false,

				danyuanList: [],
				banbenInfo: {},
				banbenId: '',
				danyuanId: '',
				chanpinId: '',
				dengjiId: '',
				curProcess: '',
				currentTabIndex: 1,
				existData: true,
				isShow: false,

				stickyHeight: 0, // 吸顶栏高度（px）
				currentStickyTitle: '', // 初始为空，不显示吸顶
				currentStickyIntro: '',
				currentStickyDengjiId: '',
				titlePositions: [],
				scrollTop: 0,
			}
		},
		components: {
			CustomTabBar,
			danyuanInfoVue,
			ezyActiveVue
		},
		onLoad(options) {
			uni.hideTabBar()
		},
		onShow() {
			this.currentTabIndex = 1
			const cacheData = cacheManager.get('xuexi-shuxue');

			if (cacheData) {
				console.log('使用缓存数据');
				this.updateFromCache();
			} else {
				console.log('重新请求数据');
				const cacheDataAuth = cacheManager.get('auth');
				this.initFromOptions(cacheDataAuth);
			}
		},
		onHide() {
			console.log('学习页面隐藏')
		},
		onUnload() {
			// 页面卸载无需特殊处理
		},
		methods: {
			goTopBtn() {
				this.scrollTop = -1; // 先设一个无效值（确保变化）
				this.$nextTick(() => {
					this.scrollTop = 0; // 再滚到顶部
				});
			},
			moreBtn() {
				uni.switchTab({
					url: '/pages/chanpinXuanze/index'
				})
			},

			initFromOptions(options) {
				console.log('options', options);
				this.chanpinId = options.chanpinId;
				this.danyuanId = options.danyuanId;
				this.banbenId = options.banbenId;
				this.dengjiId = options.dengjiId;
				this.loadDataFromApi();
			},
			// 从缓存更新数据方法
			updateFromCache() {
				updateXuexiProcess()
				const cacheData = cacheManager.get('xuexi-shuxue');
				console.log('cacheData 从缓存更新数据方法', cacheData);
				if (cacheData) {
					this.banbenInfo = { ...cacheData };
					this.curProcess = cacheData.curProcess;
					this.danyuanList = [...(cacheData.danyuanList || [])];

					this.$nextTick(() => {
						this.updateTitlePositions();
					});
				}
			},

			loadDataFromApi() {
				this.banbenInfo = {}
				this.curProcess = ''
				this.danyuanList = []
				const req = {
					banbenId: this.banbenId
				}
				shuxueChanpinBanbenInfo(req).then(res => {
					if (res.code === 0) {
						this.banbenInfo = res.data;
						this.curProcess =res.data.curProcess * 100;
						this.danyuanList = res.data.danyuanList || [];

						if (!this.danyuanList.length) {
							this.existData = false
						}
						// 保存到缓存（新增了参数保存）
						const cacheData = {
							...res.data,
							banbenId: this.banbenId,
							chanpinId: this.chanpinId,
							danyuanId: this.danyuanId,
							dengjiId: this.dengjiId
						};
						cacheManager.set('xuexi-shuxue', cacheData);

						// 更新全局auth信息
						cacheManager.updateObject('auth', {
							chanpinId: res.data.chanpinId,
							banbenId: this.banbenId,
							danyuanId: res.data.curDanyuanId,
							dengjiId: res.data.dengjiId
						});
						this.danyuanId = res.data.curDanyuanId
						this.dengjiId = res.data.dengjiId
						this.chanpinId = res.data.chanpinId
						// 数据加载完成后初始化观察器
						this.$nextTick(() => {
							this.updateTitlePositions();
						});
					}
				}).catch(res => {
					cacheManager.remove("xuexi-shuxue");
					toast("加载失败，请重试");
				});
			},

			updateStickyHeight() {
					const query = uni.createSelectorQuery().in(this);
					query.select('.item-fixed').boundingClientRect(res => {
						if (res) {
							this.stickyHeight = res.height; // 单位 px
						} else {
							this.stickyHeight = 100; // 默认 fallback（约 200rpx = 100px）
						}
					}).exec();
				},

			// 获取所有标题在 scroll-view 中的绝对位置
			updateTitlePositions() {
				this.titlePositions = [];
				this.danyuanTitleRefs = [];

				if (!this.danyuanList.length) return;

				const query = uni.createSelectorQuery().in(this);
				this.danyuanList.forEach(item => {
					query.select(`#title-${item.danyuanId}`).boundingClientRect();
					this.danyuanTitleRefs.push(item);
				});

				query.exec((rects) => {
					rects.forEach((rect, index) => {
						if (rect) {
							// 在 scroll-view 初始未滚动时，rect.top 就是内容中的绝对 top
							this.titlePositions.push({
								danyuanId: this.danyuanTitleRefs[index].danyuanId,
								name: this.danyuanTitleRefs[index].danyuanName,
								intro: this.danyuanTitleRefs[index].danyuanIntro,
								top: rect.top
							});
						}
					});
					this.titlePositions.sort((a, b) => a.top - b.top);
					// 👇 新增：更新吸顶栏高度
								this.updateStickyHeight();
				});
			},

			handleScroll(e) {
				const scrollTop = e.detail.scrollTop;
				const firstTitle = this.titlePositions[0];

				if (!firstTitle) {
					this.currentStickyTitle = '';
					return;
				}

				// 👇 关键修改：提前触发吸顶
				const triggerOffset = scrollTop + this.stickyHeightPx;

				// 如果还没滚到第一个标题的顶部（考虑吸顶高度），则隐藏
				if (triggerOffset < firstTitle.top) {
					this.currentStickyTitle = '';
					return;
				}

				// 找出最后一个 top <= triggerOffset 的标题（即刚进入吸顶区的单元）
				let matched = null;
				for (let i = this.titlePositions.length - 1; i >= 0; i--) {
					if (this.titlePositions[i].top <= triggerOffset) {
						matched = this.titlePositions[i];
						break;
					}
				}

				if (matched) {
					this.currentStickyTitle = matched.name;
					this.currentStickyIntro = matched.intro;
					this.currentStickyDengjiId = this.banbenInfo.dengjiId || 1;
				} else {
					this.currentStickyTitle = '';
				}
			},

			getJieAndDanyuan(data, jieId) {
				for (let danyuan of data.danyuanList) {
					for (let jie of danyuan.jieList) {
						if (jie.jieId == jieId) {
							return { danyuan, jie }
						}
					}
				}
				return null;
			},

			async saveAndNavigate(jieId, type, da, code) {
				if (code == 'jixu') {
					if (!this.banbenId || !this.danyuanId) {
						toast("banbenId或者danyuanId 丢失")
						return false
					}
				}

				let req = {
					"banbenId": this.banbenId,
					"danyuanId": da.danyuanId,
					"jieId": jieId
				}
				console.log('req',req);
				try {
					const res = await shuxueSave(req);
					if (res.code == 0 && res.data) {
						let curJieAndDanyuan = this.getJieAndDanyuan(this.banbenInfo, jieId);
						if (!curJieAndDanyuan) {
							toast("未找到课程信息");
							return false;
						}

						const cacheData = cacheManager.get('xuexi-shuxue') || {};
						cacheData.curDanyuanName = curJieAndDanyuan.danyuan.danyuanName;
						cacheData.curKechengName = curJieAndDanyuan.jie.jieIntro;
						cacheData.curJieId = jieId;
						cacheData.type = curJieAndDanyuan.jie.type;
						cacheManager.set('xuexi-shuxue', cacheData);

						if (type == 1) {
							uni.navigateTo({ url: `/pages/xinshuxue/lookShipin?jieId=${jieId}` })
						} else {
							uni.navigateTo({ url: `/pages/xinshuxue/unitTest?jieId=${jieId}` })
						}
					} else {
						toast("保存位置出错");
						return false;
					}
				} catch (error) {
					toast("保存失败");
					return false;
				}
			},
			handlePlay(da, code) {
				let jieId = code === 'jixu' ? da.curJieId : da.jieId;
				if (!jieId) {
					toast("无课程ID");
					return;
				}
				this.saveAndNavigate(jieId, da.type, da, code);
			},
			handleClickDanyuan(item) {
				if (!item.danyuanId) {
					toast("danyuanId丢失")
					return false
				}
				this.isShow = true;
				setTimeout(() => {
					// 更新为点击的动态单元Id [临时]
					this.$refs.dyRef.handleShow(item.danyuanId)
				}, 100)
			},
			handleBack() {
				uni.navigateTo({
					url: `/pages/chanpinXuanze/banben?dengjiId=` + this.dengjiId
				})
			},
		},

		// 计算吸顶栏下方的偏移（确保内容不被遮挡）
		computed: {
			stickyHeightPx() {
					// 175rpx ≈ 87.5px，取整 90px 足够安全
					return 90;
				},
			topOffset() {
					// 只有当吸顶栏显示时，才增加上边距避免内容被遮挡
					return this.currentStickyTitle ? '80rpx' : '0rpx';
				}

		}
	}
</script>

