<script lang="ts" setup>
import type { AiChatConversationApi } from '#/api/ai/chat/conversation';
import type { AiChatMessageApi } from '#/api/ai/chat/message';

import { computed, nextTick, onMounted, ref } from 'vue';
import { useRoute } from 'vue-router';

import { alert, confirm, Page, useVbenModal } from '@vben/common-ui';
import { IconifyIcon } from '@vben/icons';

import { Button, Layout, message, Switch } from 'ant-design-vue';

import { getChatConversationMy } from '#/api/ai/chat/conversation';
import {
  deleteByConversationId,
  getChatMessageListByConversationId,
  sendChatMessageStream,
} from '#/api/ai/chat/message';

import ConversationList from './components/conversation/ConversationList.vue';
import ConversationUpdateForm from './components/conversation/ConversationUpdateForm.vue';
import MessageList from './components/message/MessageList.vue';
import MessageListEmpty from './components/message/MessageListEmpty.vue';
import MessageLoading from './components/message/MessageLoading.vue';
import MessageNewConversation from './components/message/MessageNewConversation.vue';
/** AI 聊天对话 列表 */
defineOptions({ name: 'AiChat' });

const route = useRoute(); // 路由
const [FormModal, formModalApi] = useVbenModal({
  connectedComponent: ConversationUpdateForm,
  destroyOnClose: true,
});
// 聊天对话
const conversationListRef = ref();
const activeConversationId = ref<null | number>(null); // 选中的对话编号
const activeConversation = ref<AiChatConversationApi.ChatConversationVO | null>(
  null,
); // 选中的 Conversation
const conversationInProgress = ref(false); // 对话是否正在进行中。目前只有【发送】消息时，会更新为 true，避免切换对话、删除对话等操作

// 消息列表
const messageRef = ref();
const activeMessageList = ref<AiChatMessageApi.ChatMessageVO[]>([]); // 选中对话的消息列表
const activeMessageListLoading = ref<boolean>(false); // activeMessageList 是否正在加载中
const activeMessageListLoadingTimer = ref<any>(); // activeMessageListLoading Timer 定时器。如果加载速度很快，就不进入加载中
// 消息滚动
const textSpeed = ref<number>(50); // Typing speed in milliseconds
const textRoleRunning = ref<boolean>(false); // Typing speed in milliseconds

// 发送消息输入框
const isComposing = ref(false); // 判断用户是否在输入
const conversationInAbortController = ref<any>(); // 对话进行中 abort 控制器(控制 stream 对话)
const inputTimeout = ref<any>(); // 处理输入中回车的定时器
const prompt = ref<string>(); // prompt
const enableContext = ref<boolean>(true); // 是否开启上下文
// 接收 Stream 消息
const receiveMessageFullText = ref('');
const receiveMessageDisplayedText = ref('');

// =========== 【聊天对话】相关 ===========

/** 获取对话信息 */
const getConversation = async (id: null | number) => {
  if (!id) {
    return;
  }
  const conversation: AiChatConversationApi.ChatConversationVO =
    await getChatConversationMy(id);
  if (!conversation) {
    return;
  }
  activeConversation.value = conversation;
  activeConversationId.value = conversation.id;
};

/**
 * 点击某个对话
 *
 * @param conversation 选中的对话
 * @return 是否切换成功
 */
const handleConversationClick = async (
  conversation: AiChatConversationApi.ChatConversationVO,
) => {
  // 对话进行中，不允许切换
  if (conversationInProgress.value) {
    alert('对话中，不允许切换!');
    return false;
  }

  // 更新选中的对话 id
  activeConversationId.value = conversation.id;
  activeConversation.value = conversation;
  // 刷新 message 列表
  await getMessageList();
  // 滚动底部
  scrollToBottom(true);
  // 清空输入框
  prompt.value = '';
  return true;
};

/** 删除某个对话*/
const handlerConversationDelete = async (
  delConversation: AiChatConversationApi.ChatConversationVO,
) => {
  // 删除的对话如果是当前选中的，那么就重置
  if (activeConversationId.value === delConversation.id) {
    await handleConversationClear();
  }
};

/** 清空选中的对话 */
const handleConversationClear = async () => {
  // 对话进行中，不允许切换
  if (conversationInProgress.value) {
    alert('对话中，不允许切换!');
    return false;
  }
  activeConversationId.value = null;
  activeConversation.value = null;
  activeMessageList.value = [];
};

const openChatConversationUpdateForm = async () => {
  formModalApi.setData({ id: activeConversationId.value }).open();
};
const handleConversationUpdateSuccess = async () => {
  // 对话更新成功，刷新最新信息
  await getConversation(activeConversationId.value);
};

/** 处理聊天对话的创建成功 */
const handleConversationCreate = async () => {
  // 创建对话
  await conversationListRef.value.createConversation();
};
/** 处理聊天对话的创建成功 */
const handleConversationCreateSuccess = async () => {
  // 创建新的对话，清空输入框
  prompt.value = '';
};

// =========== 【消息列表】相关 ===========

/** 获取消息 message 列表 */
const getMessageList = async () => {
  try {
    if (activeConversationId.value === null) {
      return;
    }
    // Timer 定时器，如果加载速度很快，就不进入加载中
    activeMessageListLoadingTimer.value = setTimeout(() => {
      activeMessageListLoading.value = true;
    }, 60);

    // 获取消息列表
    activeMessageList.value = await getChatMessageListByConversationId(
      activeConversationId.value,
    );

    // 滚动到最下面
    await nextTick();
    await scrollToBottom();
  } finally {
    // time 定时器，如果加载速度很快，就不进入加载中
    if (activeMessageListLoadingTimer.value) {
      clearTimeout(activeMessageListLoadingTimer.value);
    }
    // 加载结束
    activeMessageListLoading.value = false;
  }
};

/**
 * 消息列表
 *
 * 和 {@link #getMessageList()} 的差异是，把 systemMessage 考虑进去
 */
const messageList = computed(() => {
  if (activeMessageList.value.length > 0) {
    return activeMessageList.value;
  }
  // 没有消息时，如果有 systemMessage 则展示它
  if (activeConversation.value?.systemMessage) {
    return [
      {
        id: 0,
        type: 'system',
        content: activeConversation.value.systemMessage,
      },
    ];
  }
  return [];
});

/** 处理删除 message 消息 */
const handleMessageDelete = () => {
  if (conversationInProgress.value) {
    alert('回答中，不能删除!');
    return;
  }
  // 刷新 message 列表
  getMessageList();
};

/** 处理 message 清空 */
const handlerMessageClear = async () => {
  if (!activeConversationId.value) {
    return;
  }
  try {
    // 确认提示
    await confirm('确认清空对话消息？');
    // 清空对话
    await deleteByConversationId(activeConversationId.value);
    // 刷新 message 列表
    activeMessageList.value = [];
  } catch {}
};

/** 回到 message 列表的顶部 */
const handleGoTopMessage = () => {
  messageRef.value.handlerGoTop();
};

// =========== 【发送消息】相关 ===========
/** 处理来自 keydown 的发送消息 */
const handleSendByKeydown = async (event: any) => {
  // 判断用户是否在输入
  if (isComposing.value) {
    return;
  }
  // 进行中不允许发送
  if (conversationInProgress.value) {
    return;
  }
  const content = prompt.value?.trim() as string;
  if (event.key === 'Enter') {
    if (event.shiftKey) {
      // 插入换行
      prompt.value += '\r\n';
      event.preventDefault(); // 防止默认的换行行为
    } else {
      // 发送消息
      await doSendMessage(content);
      event.preventDefault(); // 防止默认的提交行为
    }
  }
};

/** 处理来自【发送】按钮的发送消息 */
const handleSendByButton = () => {
  doSendMessage(prompt.value?.trim() as string);
};

/** 处理 prompt 输入变化 */
const handlePromptInput = (event) => {
  // 非输入法 输入设置为 true
  if (!isComposing.value) {
    // 回车 event data 是 null
    if (event.data === null || event.data === 'null') {
      return;
    }
    isComposing.value = true;
  }
  // 清理定时器
  if (inputTimeout.value) {
    clearTimeout(inputTimeout.value);
  }
  // 重置定时器
  inputTimeout.value = setTimeout(() => {
    isComposing.value = false;
  }, 400);
};

const onCompositionstart = () => {
  isComposing.value = true;
};

const onCompositionend = () => {
  // console.log('输入结束...')
  setTimeout(() => {
    isComposing.value = false;
  }, 200);
};

/** 真正执行【发送】消息操作 */
const doSendMessage = async (content: string) => {
  // 校验
  if (content.length === 0) {
    message.error('发送失败，原因：内容为空！');
    return;
  }
  if (activeConversationId.value == null) {
    message.error('还没创建对话，不能发送!');
    return;
  }
  // 清空输入框
  prompt.value = '';
  // 执行发送
  await doSendMessageStream({
    conversationId: activeConversationId.value,
    content,
  } as AiChatMessageApi.ChatMessageVO);
};

/** 真正执行【发送】消息操作 */
const doSendMessageStream = async (
  userMessage: AiChatMessageApi.ChatMessageVO,
) => {
  // 创建 AbortController 实例，以便中止请求
  conversationInAbortController.value = new AbortController();
  // 标记对话进行中
  conversationInProgress.value = true;
  // 设置为空
  receiveMessageFullText.value = '';

  try {
    // 1.1 先添加两个假数据，等 stream 返回再替换
    activeMessageList.value.push(
      {
        id: -1,
        conversationId: activeConversationId.value,
        type: 'user',
        content: userMessage.content,
        createTime: new Date(),
      } as AiChatMessageApi.ChatMessageVO,
      {
        id: -2,
        conversationId: activeConversationId.value,
        type: 'assistant',
        content: '思考中...',
        createTime: new Date(),
      } as AiChatMessageApi.ChatMessageVO,
    );
    // 1.2 滚动到最下面
    await nextTick();
    await scrollToBottom(); // 底部
    // 1.3 开始滚动
    textRoll();

    // 2. 发送 event stream
    let isFirstChunk = true; // 是否是第一个 chunk 消息段
    await sendChatMessageStream(
      userMessage.conversationId,
      userMessage.content,
      conversationInAbortController.value,
      enableContext.value,
      async (res: any) => {
        const { code, data, msg } = JSON.parse(res.data);
        if (code !== 0) {
          alert(`对话异常! ${msg}`);
          return;
        }

        // 如果内容为空，就不处理。
        if (data.receive.content === '') {
          return;
        }
        // 首次返回需要添加一个 message 到页面，后面的都是更新
        if (isFirstChunk) {
          isFirstChunk = false;
          // 弹出两个假数据
          activeMessageList.value.pop();
          activeMessageList.value.pop();
          // 更新返回的数据
          activeMessageList.value.push(data.send, data.receive);
        }
        // debugger
        receiveMessageFullText.value =
          receiveMessageFullText.value + data.receive.content;
        // 滚动到最下面
        await scrollToBottom();
      },
      (error: any) => {
        alert(`对话异常! ${error}`);
        stopStream();
        // 需要抛出异常，禁止重试
        throw error;
      },
      () => {
        stopStream();
      },
    );
  } catch {}
};

/** 停止 stream 流式调用 */
const stopStream = async () => {
  // tip：如果 stream 进行中的 message，就需要调用 controller 结束
  if (conversationInAbortController.value) {
    conversationInAbortController.value.abort();
  }
  // 设置为 false
  conversationInProgress.value = false;
};

/** 编辑 message：设置为 prompt，可以再次编辑 */
const handleMessageEdit = (message: AiChatMessageApi.ChatMessageVO) => {
  prompt.value = message.content;
};

/** 刷新 message：基于指定消息，再次发起对话 */
const handleMessageRefresh = (message: AiChatMessageApi.ChatMessageVO) => {
  doSendMessage(message.content);
};

// ============== 【消息滚动】相关 =============

/** 滚动到 message 底部 */
const scrollToBottom = async (isIgnore?: boolean) => {
  await nextTick();
  if (messageRef.value) {
    messageRef.value.scrollToBottom(isIgnore);
  }
};

/** 自提滚动效果 */
const textRoll = async () => {
  let index = 0;
  try {
    // 只能执行一次
    if (textRoleRunning.value) {
      return;
    }
    // 设置状态
    textRoleRunning.value = true;
    receiveMessageDisplayedText.value = '';
    const task = async () => {
      // 调整速度
      const diff =
        (receiveMessageFullText.value.length -
          receiveMessageDisplayedText.value.length) /
        10;
      if (diff > 5) {
        textSpeed.value = 10;
      } else if (diff > 2) {
        textSpeed.value = 30;
      } else if (diff > 1.5) {
        textSpeed.value = 50;
      } else {
        textSpeed.value = 100;
      }
      // 对话结束，就按 30 的速度
      if (!conversationInProgress.value) {
        textSpeed.value = 10;
      }

      if (index < receiveMessageFullText.value.length) {
        receiveMessageDisplayedText.value +=
          receiveMessageFullText.value[index];
        index++;

        // 更新 message
        const lastMessage =
          activeMessageList.value[activeMessageList.value.length - 1];
        if (lastMessage)
          lastMessage.content = receiveMessageDisplayedText.value;
        // 滚动到住下面
        await scrollToBottom();
        // 重新设置任务
        timer = setTimeout(task, textSpeed.value);
      } else {
        // 不是对话中可以结束
        if (conversationInProgress.value) {
          // 重新设置任务
          timer = setTimeout(task, textSpeed.value);
        } else {
          textRoleRunning.value = false;
          clearTimeout(timer);
        }
      }
    };
    let timer = setTimeout(task, textSpeed.value);
  } catch {}
};

/** 初始化 */
onMounted(async () => {
  // 如果有 conversationId 参数，则默认选中
  if (route.query.conversationId) {
    const id = route.query.conversationId as unknown as number;
    activeConversationId.value = id;
    await getConversation(id);
  }

  // 获取列表数据
  activeMessageListLoading.value = true;
  await getMessageList();
});
</script>

<template>
  <Page auto-content-height>
    <Layout class="ai-layout">
      <!-- 左侧：对话列表 -->
      <ConversationList
        :active-id="activeConversationId"
        ref="conversationListRef"
        @on-conversation-create="handleConversationCreateSuccess"
        @on-conversation-click="handleConversationClick"
        @on-conversation-clear="handleConversationClear"
        @on-conversation-delete="handlerConversationDelete"
      />
      <Layout class="detail-container">
        <Layout.Header class="header">
          <div class="title">
            {{ activeConversation?.title ? activeConversation?.title : '对话' }}
            <span v-if="activeMessageList.length > 0">
              ({{ activeMessageList.length }})
            </span>
          </div>
          <div class="btns" v-if="activeConversation">
            <Button
              type="primary"
              ghost
              class="mr-[10px]"
              size="small"
              @click="openChatConversationUpdateForm"
            >
              <span v-html="activeConversation?.modelName"></span>
              <IconifyIcon icon="ep:setting" class="ml-[10px]" />
            </Button>
            <Button
              size="small"
              class="btn mr-[10px]"
              @click="handlerMessageClear"
            >
              <IconifyIcon
                icon="heroicons-outline:archive-box-x-mark"
                color="#787878"
              />
            </Button>
            <Button size="small" class="btn mr-[10px]">
              <IconifyIcon icon="ep:download" color="#787878" />
            </Button>
            <Button
              size="small"
              class="btn mr-[10px]"
              @click="handleGoTopMessage"
            >
              <IconifyIcon icon="ep:top" color="#787878" />
            </Button>
          </div>
        </Layout.Header>
        <Layout.Content class="main-container">
          <div>
            <div class="message-container">
              <!-- 情况一：消息加载中 -->
              <MessageLoading v-if="activeMessageListLoading" />
              <!-- 情况二：无聊天对话时 -->
              <MessageNewConversation
                v-if="!activeConversation"
                @on-new-conversation="handleConversationCreate"
              />
              <!-- 情况三：消息列表为空 -->
              <MessageListEmpty
                v-if="
                  !activeMessageListLoading &&
                  messageList.length === 0 &&
                  activeConversation
                "
                @on-prompt="doSendMessage"
              />
              <!-- 情况四：消息列表不为空 -->
              <MessageList
                v-if="!activeMessageListLoading && messageList.length > 0"
                ref="messageRef"
                :conversation="activeConversation"
                :list="messageList"
                @on-delete-success="handleMessageDelete"
                @on-edit="handleMessageEdit"
                @on-refresh="handleMessageRefresh"
              />
            </div>
          </div>
        </Layout.Content>
        <Layout.Footer class="footer-container">
          <form class="prompt-from">
            <textarea
              class="prompt-input"
              v-model="prompt"
              @keydown="handleSendByKeydown"
              @input="handlePromptInput"
              @compositionstart="onCompositionstart"
              @compositionend="onCompositionend"
              placeholder="问我任何问题...（Shift+Enter 换行，按下 Enter 发送）"
            ></textarea>
            <div class="prompt-btns">
              <div>
                <Switch v-model:checked="enableContext" />
                <span class="ml-5px text-14px text-#8f8f8f">上下文</span>
              </div>
              <Button
                type="primary"
                @click="handleSendByButton"
                :loading="conversationInProgress"
                v-if="conversationInProgress === false"
              >
                {{ conversationInProgress ? '进行中' : '发送' }}
              </Button>
              <Button
                danger
                @click="stopStream()"
                v-if="conversationInProgress === true"
              >
                停止
              </Button>
            </div>
          </form>
        </Layout.Footer>
      </Layout>
    </Layout>
    <FormModal @success="handleConversationUpdateSuccess" />
  </Page>
</template>

<style lang="scss" scoped>
.ai-layout {
  position: absolute;
  top: 0;
  left: 0;
  flex: 1;
  width: 100%;
  height: 100%;
}

.conversation-container {
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: 10px 10px 0;

  .btn-new-conversation {
    padding: 18px 0;
  }

  .search-input {
    margin-top: 20px;
  }

  .conversation-list {
    margin-top: 20px;

    .conversation {
      display: flex;
      flex: 1;
      flex-direction: row;
      align-items: center;
      justify-content: space-between;
      padding: 0 5px;
      margin-top: 10px;
      line-height: 30px;
      cursor: pointer;
      border-radius: 5px;

      &.active {
        background-color: #e6e6e6;

        .button {
          display: inline-block;
        }
      }

      .title-wrapper {
        display: flex;
        flex-direction: row;
        align-items: center;
      }

      .title {
        max-width: 220px;
        padding: 5px 10px;
        overflow: hidden;
        text-overflow: ellipsis;
        font-size: 14px;
        white-space: nowrap;
      }

      .avatar {
        display: flex;
        flex-direction: row;
        justify-items: center;
        width: 28px;
        height: 28px;
      }

      // 对话编辑、删除
      .button-wrapper {
        right: 2px;
        display: flex;
        flex-direction: row;
        justify-items: center;
        color: #606266;

        .el-icon {
          margin-right: 5px;
        }
      }
    }
  }

  // 角色仓库、清空未设置对话
  .tool-box {
    display: flex;
    align-items: center;
    justify-content: space-between;
    line-height: 35px;
    color: var(--el-text-color);

    > div {
      display: flex;
      align-items: center;
      padding: 0;
      margin: 0;
      color: #606266;
      cursor: pointer;

      > span {
        margin-left: 5px;
      }
    }
  }
}

// 头部
.detail-container {
  background: #fff;

  .header {
    display: flex;
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    background: #fbfbfb;
    box-shadow: 0 0 0 0 #dcdfe6;

    .title {
      font-size: 18px;
      font-weight: bold;
    }

    .btns {
      display: flex;
      flex-direction: row;
      justify-content: flex-end;
      width: 300px;
      //justify-content: space-between;

      .btn {
        padding: 0 10px;
      }
    }
  }
}

// main 容器
.main-container {
  position: relative;
  width: 100%;
  height: 100%;
  padding: 0;
  margin: 0;

  .message-container {
    position: absolute;
    inset: 0;
    padding: 0;
    margin: 0;
    overflow-y: hidden;
  }
}

// 底部
.footer-container {
  display: flex;
  flex-direction: column;
  height: auto;
  padding: 0;
  margin: 0;
  background-color: white;

  .prompt-from {
    display: flex;
    flex-direction: column;
    height: auto;
    padding: 9px 10px;
    margin: 10px 20px 20px;
    border: 1px solid #e3e3e3;
    border-radius: 10px;
  }

  .prompt-input {
    box-sizing: border-box;
    height: 80px;
    padding: 0 2px;
    overflow: auto;
    resize: none;
    //box-shadow: none;
    border: none;
  }

  .prompt-input:focus {
    outline: none;
  }

  .prompt-btns {
    display: flex;
    justify-content: space-between;
    padding-top: 5px;
    padding-bottom: 0;
  }
}
</style>
