/*
 * AgentMail 鸿蒙客户端 — 主框架（底部 Tab 导航）
 * 收件箱 / 会话 / 联系人 三个 TabContent
 */
import { ApiClient, ApiError } from '../api/ApiClient';
import { MailApi, InboxResponse } from '../api/MailApi';
import { AccountManager, AccountInfo } from '../api/AccountManager';
import { SseService, SseEvent } from '../api/SseService';
import { MailSummary, Session, Contact } from '../model/Models';
import { MailDetailParams, ComposeParams } from '../model/RouteParams';
import { promptAction } from '@kit.ArkUI';

@Component
struct InboxTab {
  @State mails: MailSummary[] = [];
  @State loading: boolean = false;
  @State total: number = 0;
  @State unread: number = 0;
  @State error: string = '';
  @State accountName: string = '';
  @State accountFilter: string = 'all'; // 'all' 或 accountId
  @State showAccountPicker: boolean = false;
  @State accountList: AccountInfo[] = [];
  private sseService: SseService | null = null;

  aboutToAppear(): void {
    const ctx = this.getUIContext().getHostContext();
    if (ctx !== undefined) {
      this.sseService = SseService.getInstance();
      // 加载账号列表
      const acctMgr: AccountManager = AccountManager.getInstance(ctx);
      acctMgr.load().then(() => {
        const active = acctMgr.getActiveAccount();
        if (active !== null) {
          this.accountName = active.displayName;
        }
        this.accountList = acctMgr.getAccounts();
        if (this.accountList.length <= 1) {
          this.accountFilter = 'all';
        }
      });
      this.loadData();
      // 全局 SSE 监听（所有账号的事件都会收到）；保存同一函数引用以便页面退出时移除。
      this.sseService.addListener(this.onSseEvent);
    }
  }

  aboutToDisappear(): void {
    if (this.sseService !== null) {
      this.sseService.removeListener(this.onSseEvent);
    }
  }

  private onSseEvent = (event: SseEvent): void => {
    if (event.type === 'new_mail') {
      let sourceName: string = '';
      for (let i = 0; i < this.accountList.length; i++) {
        if (this.accountList[i].id === event.accountId) {
          sourceName = this.accountList[i].displayName;
          break;
        }
      }
      promptAction.showToast({ message: sourceName.length > 0 ? '📨 ' + sourceName + ' 收到新邮件' : '📨 新邮件到达' });
      this.loadData();
    }
  };

  async loadData(): Promise<void> {
    const ctx = this.getUIContext().getHostContext();
    if (ctx === undefined) {
      return;
    }
    this.loading = true;
    this.error = '';
    try {
      const acctMgr: AccountManager = AccountManager.getInstance(ctx);
      await acctMgr.load();
      const allAccounts: AccountInfo[] = acctMgr.getAccounts();
      this.accountList = allAccounts;

      let filterExists: boolean = this.accountFilter === 'all';
      for (let i = 0; i < allAccounts.length; i++) {
        if (allAccounts[i].id === this.accountFilter) {
          filterExists = true;
          this.accountName = allAccounts[i].displayName;
          break;
        }
      }
      if (!filterExists) {
        this.accountFilter = 'all';
        this.accountName = '全部邮箱';
      }

      const mergedMails: MailSummary[] = [];
      let mergedTotal: number = 0;

      for (let i = 0; i < allAccounts.length; i++) {
        const acct: AccountInfo = allAccounts[i];
        if (this.accountFilter !== 'all' && this.accountFilter !== acct.id) {
          continue;
        }
        try {
          const accountClient: ApiClient = new ApiClient(ctx);
          accountClient.setBase(acct.server);
          accountClient.setToken(acct.token);
          const response: InboxResponse = await new MailApi(accountClient).inbox('all', 50);
          for (let j = 0; j < response.mails.length; j++) {
            const mail: MailSummary = response.mails[j];
            mail.source_account_id = acct.id;
            mail.source_account_name = acct.displayName;
            mergedMails.push(mail);
          }
          mergedTotal += response.total;
        } catch (e) {
          if (this.accountFilter !== 'all') {
            throw e as ApiError;
          }
        }
      }

      mergedMails.sort((a: MailSummary, b: MailSummary) => {
        if (a.created_at > b.created_at) {
          return -1;
        }
        if (a.created_at < b.created_at) {
          return 1;
        }
        return 0;
      });
      this.mails = mergedMails;
      this.total = mergedTotal;

      let unreadCount: number = 0;
      for (let i = 0; i < this.mails.length; i++) {
        if (this.mails[i].status === 'unread') {
          unreadCount++;
        }
      }
      this.unread = unreadCount;
    } catch (e) {
      const ae = e as ApiError;
      this.error = ae.message.length > 0 ? ae.message : '加载失败';
    } finally {
      this.loading = false;
    }
  }

  openCompose(): void {
    let accountId: string = this.accountFilter === 'all' ? '' : this.accountFilter;
    if (accountId.length === 0) {
      const ctx = this.getUIContext().getHostContext();
      if (ctx !== undefined) {
        accountId = AccountManager.getInstance(ctx).getActiveId();
      }
    }
    const params: ComposeParams = {
      to: '',
      reply_to: '',
      session_alias: '',
      account_id: accountId
    };
    this.getUIContext().getRouter().pushUrl({ url: 'pages/ComposePage', params: params });
  }

  build() {
    Column() {
      Row() {
        Column() {
          Row() {
            Text('收件箱').fontSize(20).fontWeight(FontWeight.Bold).fontColor('#333333')
            if (this.accountList.length > 1) {
              Text(' ▾').fontSize(14).fontColor('#999999')
                .onClick(() => { this.showAccountPicker = !this.showAccountPicker; })
            }
          }
          Text(this.accountFilter === 'all' ? '全部邮箱' : this.accountName)
            .fontSize(11).fontColor('#999999').margin({ top: 2 })
            .onClick(() => { if (this.accountList.length > 1) { this.showAccountPicker = !this.showAccountPicker; } })
        }
        .alignItems(HorizontalAlign.Start)
        Blank()
        if (this.unread > 0) {
          Text(this.unread + ' 未读')
            .fontSize(13).fontColor('#FFFFFF')
            .backgroundColor('#FF4444')
            .borderRadius(10)
            .padding({ left: 8, right: 8, top: 2, bottom: 2 })
        }
        Text('⚙')
          .fontSize(20).fontColor('#666666')
          .width(36).height(36).textAlign(TextAlign.Center)
          .onClick(() => {
            this.getUIContext().getRouter().pushUrl({ url: 'pages/SettingsPage' });
          })
      }
      .width('100%').height(56).padding({ left: 16, right: 8 })
      .backgroundColor('#FFFFFF')

      // 账号选择器下拉
      if (this.showAccountPicker && this.accountList.length > 1) {
        Column() {
          Text('全部邮箱')
            .fontSize(14).fontColor(this.accountFilter === 'all' ? '#1A73E8' : '#333333')
            .fontWeight(this.accountFilter === 'all' ? FontWeight.Bold : FontWeight.Normal)
            .width('100%').height(40).padding({ left: 16 })
            .backgroundColor(this.accountFilter === 'all' ? '#F0F7FF' : '#FFFFFF')
            .onClick(() => {
              this.accountFilter = 'all';
              this.accountName = '全部邮箱';
              this.showAccountPicker = false;
              this.loadData();
            })
          ForEach(this.accountList, (acct: AccountInfo) => {
            Row() {
              Column() {
                Text(acct.displayName)
                  .fontSize(14)
                  .fontColor(this.accountFilter === acct.id ? '#1A73E8' : '#333333')
                  .fontWeight(this.accountFilter === acct.id ? FontWeight.Bold : FontWeight.Normal)
                Text(acct.username)
                  .fontSize(11).fontColor('#999999')
              }
              .alignItems(HorizontalAlign.Start)
              .layoutWeight(1)
            }
            .width('100%').height(48).padding({ left: 16 })
            .backgroundColor(this.accountFilter === acct.id ? '#F0F7FF' : '#FFFFFF')
            .onClick(() => {
              this.accountFilter = acct.id;
              this.accountName = acct.displayName;
              this.showAccountPicker = false;
              this.loadData();
            })
          }, (acct: AccountInfo) => acct.id)
        }
        .width('100%')
        .backgroundColor('#FFFFFF')
        .border({ width: { bottom: 1 }, color: '#EEEEEE' })
      }

      if (this.loading) {
        Column() {
          LoadingProgress().width(40).height(40)
        }
        .width('100%').layoutWeight(1).justifyContent(FlexAlign.Center)
      } else if (this.error.length > 0) {
        Column() {
          Text(this.error).fontSize(14).fontColor('#FF4444')
          Button('重试').margin({ top: 12 }).onClick(() => { this.loadData(); })
        }
        .width('100%').layoutWeight(1).justifyContent(FlexAlign.Center)
      } else if (this.mails.length === 0) {
        Column() {
          Text('📭 收件箱为空').fontSize(16).fontColor('#999999')
        }
        .width('100%').layoutWeight(1).justifyContent(FlexAlign.Center)
      } else {
        List({ space: 1 }) {
          ForEach(this.mails, (mail: MailSummary) => {
            ListItem() {
              this.MailItem(mail)
            }
            .height(80)
            .backgroundColor(mail.status === 'unread' ? '#F0F7FF' : '#FFFFFF')
            .onClick(() => {
              const params: MailDetailParams = {
                mail_id: mail.mail_id,
                account_id: mail.source_account_id
              };
              this.getUIContext().getRouter().pushUrl({
                url: 'pages/MailDetailPage',
                params: params
              });
            })
          }, (mail: MailSummary) => mail.source_account_id + ':' + mail.mail_id)
        }
        .width('100%').layoutWeight(1)
        .divider({ strokeWidth: 1, color: '#EEEEEE', startMargin: 16, endMargin: 16 })
      }

      // 底部信息栏 + 悬浮写邮件按钮
      Stack({ alignContent: Alignment.BottomEnd }) {
        Row() {
          Text('共 ' + this.total + ' 封').fontSize(12).fontColor('#999999')
          Blank()
          Text('未读 ' + this.unread).fontSize(12).fontColor('#999999')
        }
        .width('100%').height(36).padding({ left: 16, right: 16 })
        .backgroundColor('#FFFFFF')

        Text('+')
          .fontSize(28).fontColor('#FFFFFF')
          .width(56).height(56)
          .borderRadius(28)
          .backgroundColor('#1A73E8')
          .textAlign(TextAlign.Center)
          .margin({ right: 20, bottom: 44 })
          .onClick(() => {
            this.openCompose();
          })
      }
      .width('100%')
    }
    .width('100%').height('100%')
    .backgroundColor('#F5F7FA')
    .bindSheet($$this.composeVisible, this.ComposeSheet())
  }

  @State composeVisible: boolean = false;

  @Builder
  ComposeSheet() {
    Column() {
      Text('写邮件').fontSize(16).fontWeight(FontWeight.Bold).fontColor('#333333')
        .margin({ top: 16, bottom: 8 })
      Button('新建邮件')
        .width('90%').height(44).backgroundColor('#1A73E8')
        .onClick(() => {
          this.composeVisible = false;
          this.openCompose();
        })
      Button('取消')
        .width('90%').height(40).backgroundColor('#F5F5F5').fontColor('#666666')
        .margin({ top: 8 })
        .onClick(() => { this.composeVisible = false; })
    }
    .width('100%').height(180).padding(16)
  }

  @Builder
  MailItem(mail: MailSummary) {
    Row() {
      Column() {
        if (mail.status === 'unread') {
          Circle({ width: 8, height: 8 }).fill('#1A73E8')
        }
      }
      .width(20).height('100%').justifyContent(FlexAlign.Center)

      Column() {
        Row() {
          Text(mail.from_name).fontSize(14).fontWeight(mail.status === 'unread' ? FontWeight.Bold : FontWeight.Normal).fontColor('#333333')
          if (this.accountFilter === 'all' && mail.source_account_name.length > 0) {
            Text(mail.source_account_name)
              .fontSize(10).fontColor('#1A73E8')
              .backgroundColor('#E8F0FE').borderRadius(4)
              .padding({ left: 5, right: 5, top: 1, bottom: 1 })
              .margin({ left: 6 })
          }
          Blank()
          Text(mail.created_at).fontSize(11).fontColor('#999999')
        }
        .width('100%')

        Text(mail.subject).fontSize(13).fontColor('#333333')
          .maxLines(1).textOverflow({ overflow: TextOverflow.Ellipsis })
          .margin({ top: 2 })
        Text(mail.body_preview).fontSize(12).fontColor('#999999')
          .maxLines(1).textOverflow({ overflow: TextOverflow.Ellipsis })
          .margin({ top: 2 })
      }
      .layoutWeight(1).height('100%')
      .alignItems(HorizontalAlign.Start)
      .padding({ left: 8 })

      if (mail.permission_mode.length > 0) {
        Text(mail.permission_mode)
          .fontSize(10).fontColor('#666666')
          .backgroundColor('#EEEEEE').borderRadius(4)
          .padding({ left: 4, right: 4, top: 1, bottom: 1 })
      }
    }
    .width('100%').height('100%')
    .padding({ left: 12, right: 12 })
    .alignItems(VerticalAlign.Center)
  }
}

@Component
struct SessionsTab {
  @State sessions: Session[] = [];
  @State loading: boolean = false;
  @State error: string = '';
  private mailApi: MailApi | null = null;

  aboutToAppear(): void {
    const ctx = this.getUIContext().getHostContext();
    if (ctx !== undefined) {
      this.mailApi = new MailApi(ApiClient.getInstance(ctx));
      this.loadData();
    }
  }

  async loadData(): Promise<void> {
    const m: MailApi | null = this.mailApi;
    if (m === null) {
      return;
    }
    this.loading = true;
    try {
      const resp = await m.sessions();
      this.sessions = resp.sessions;
    } catch (e) {
      const ae = e as ApiError;
      this.error = ae.message.length > 0 ? ae.message : '加载失败';
    } finally {
      this.loading = false;
    }
  }

  build() {
    Column() {
      Row() {
        Text('会话').fontSize(20).fontWeight(FontWeight.Bold).fontColor('#333333')
      }
      .width('100%').height(56).padding({ left: 16 })
      .backgroundColor('#FFFFFF')

      if (this.loading) {
        Column() {
          LoadingProgress().width(40).height(40)
        }
        .width('100%').layoutWeight(1).justifyContent(FlexAlign.Center)
      } else if (this.error.length > 0) {
        Column() {
          Text(this.error).fontSize(14).fontColor('#FF4444')
        }
        .width('100%').layoutWeight(1).justifyContent(FlexAlign.Center)
      } else if (this.sessions.length === 0) {
        Column() {
          Text('📭 暂无会话').fontSize(16).fontColor('#999999')
        }
        .width('100%').layoutWeight(1).justifyContent(FlexAlign.Center)
      } else {
        List({ space: 1 }) {
          ForEach(this.sessions, (s: Session, idx: number) => {
            ListItem() {
              this.SessionItem(s, idx)
            }
            .height(90)
          }, (_s: Session, idx: number) => idx.toString())
        }
        .width('100%').layoutWeight(1)
        .divider({ strokeWidth: 1, color: '#EEEEEE', startMargin: 16, endMargin: 16 })
      }
    }
    .width('100%').height('100%')
    .backgroundColor('#F5F7FA')
  }

  @Builder
  SessionItem(s: Session, idx: number) {
    Row() {
      Column() {
        Row() {
          Text(s.session_alias.length > 0 ? s.session_alias : ('会话 #' + (idx + 1)))
            .fontSize(14).fontWeight(FontWeight.Bold).fontColor('#333333')
            .maxLines(1).textOverflow({ overflow: TextOverflow.Ellipsis })
            .layoutWeight(1)
          if (s.max_rounds > 0) {
            Text(s.used_rounds + '/' + s.max_rounds)
              .fontSize(11).fontColor(s.used_rounds >= s.max_rounds ? '#FF4444' : '#666666')
              .backgroundColor(s.used_rounds >= s.max_rounds ? '#FFEBEE' : '#F5F5F5')
              .borderRadius(4).padding({ left: 4, right: 4, top: 1, bottom: 1 })
          }
        }
        .width('100%')

        Text('对方: ' + s.from_agent).fontSize(12).fontColor('#666666').margin({ top: 4 })

        Row() {
          Text(s.permission_mode.length > 0 ? s.permission_mode : '—')
            .fontSize(11).fontColor('#666666')
            .backgroundColor('#F0F0F0').borderRadius(4)
            .padding({ left: 4, right: 4, top: 1, bottom: 1 })
          Blank()
          Text(s.mail_count + ' 封').fontSize(11).fontColor('#999999')
          Text(' · ' + s.status).fontSize(11).fontColor(s.status === 'active' ? '#4CAF50' : '#999999')
        }
        .width('100%').margin({ top: 4 })
      }
      .layoutWeight(1).height('100%')
      .alignItems(HorizontalAlign.Start)
      .justifyContent(FlexAlign.SpaceBetween)
    }
    .width('100%').height('100%')
    .padding({ left: 16, right: 16, top: 12, bottom: 12 })
    .alignItems(VerticalAlign.Center)
  }
}

@Component
struct ContactsTab {
  @State contacts: Contact[] = [];
  @State loading: boolean = false;
  @State error: string = '';
  private mailApi: MailApi | null = null;

  aboutToAppear(): void {
    const ctx = this.getUIContext().getHostContext();
    if (ctx !== undefined) {
      this.mailApi = new MailApi(ApiClient.getInstance(ctx));
      this.loadData();
    }
  }

  async loadData(): Promise<void> {
    const m: MailApi | null = this.mailApi;
    if (m === null) {
      return;
    }
    this.loading = true;
    try {
      const resp = await m.contacts();
      this.contacts = resp.contacts;
    } catch (e) {
      const ae = e as ApiError;
      this.error = ae.message.length > 0 ? ae.message : '加载失败';
    } finally {
      this.loading = false;
    }
  }

  build() {
    Column() {
      Row() {
        Text('联系人').fontSize(20).fontWeight(FontWeight.Bold).fontColor('#333333')
      }
      .width('100%').height(56).padding({ left: 16 })
      .backgroundColor('#FFFFFF')

      if (this.loading) {
        Column() {
          LoadingProgress().width(40).height(40)
        }
        .width('100%').layoutWeight(1).justifyContent(FlexAlign.Center)
      } else if (this.error.length > 0) {
        Column() {
          Text(this.error).fontSize(14).fontColor('#FF4444')
          Button('重试').margin({ top: 12 }).onClick(() => { this.loadData(); })
        }
        .width('100%').layoutWeight(1).justifyContent(FlexAlign.Center)
      } else if (this.contacts.length === 0) {
        Column() {
          Text('📭 暂无联系人').fontSize(16).fontColor('#999999')
        }
        .width('100%').layoutWeight(1).justifyContent(FlexAlign.Center)
      } else {
        List({ space: 1 }) {
          ForEach(this.contacts, (c: Contact, idx: number) => {
            ListItem() {
              this.ContactItem(c, idx)
            }
            .height(85)
          }, (_c: Contact, idx: number) => idx.toString())
        }
        .width('100%').layoutWeight(1)
        .divider({ strokeWidth: 1, color: '#EEEEEE', startMargin: 16, endMargin: 16 })
      }
    }
    .width('100%').height('100%')
    .backgroundColor('#F5F7FA')
  }

  @Builder
  ContactItem(c: Contact, idx: number) {
    Row() {
      Column() {
        Row() {
          Text(c.agent_name).fontSize(14).fontWeight(FontWeight.Bold).fontColor('#333333')
          Blank()
          if (c.unread_count > 0) {
            Text(c.unread_count + '')
              .fontSize(11).fontColor('#FFFFFF')
              .backgroundColor('#FF4444')
              .borderRadius(10).width(20).height(20)
              .textAlign(TextAlign.Center)
          }
        }
        .width('100%')

        Text(c.subject.length > 0 ? c.subject : c.session_alias)
          .fontSize(12).fontColor('#666666')
          .maxLines(1).textOverflow({ overflow: TextOverflow.Ellipsis })
          .margin({ top: 3 })

        Row() {
          Text(c.permission_mode.length > 0 ? c.permission_mode : '—')
            .fontSize(10).fontColor('#666666')
            .backgroundColor('#F0F0F0').borderRadius(4)
            .padding({ left: 4, right: 4, top: 1, bottom: 1 })
          Blank()
          Text(c.last_preview.length > 0 ? c.last_preview : '—')
            .fontSize(11).fontColor('#999999')
            .maxLines(1).textOverflow({ overflow: TextOverflow.Ellipsis })
            .layoutWeight(1)
        }
        .width('100%').margin({ top: 3 })
      }
      .layoutWeight(1).height('100%')
      .alignItems(HorizontalAlign.Start)
      .justifyContent(FlexAlign.SpaceBetween)
    }
    .width('100%').height('100%')
    .padding({ left: 16, right: 16, top: 10, bottom: 10 })
    .alignItems(VerticalAlign.Center)
  }
}

@Entry
@Component
struct MainPage {
  @State currentIndex: number = 0;

  @Builder
  TabBarBuilder(title: string, icon: string) {
    Column() {
      Text(icon).fontSize(20)
      Text(title).fontSize(11).fontColor(this.currentIndex === 0 ? '#1A73E8' : '#666666')
    }
    .width('100%')
    .justifyContent(FlexAlign.Center)
  }

  build() {
    Tabs({ barPosition: BarPosition.End }) {
      TabContent() {
        InboxTab()
      }
      .tabBar(this.TabBarBuilder('收件箱', '📬'))

      TabContent() {
        SessionsTab()
      }
      .tabBar(this.TabBarBuilder('会话', '💬'))

      TabContent() {
        ContactsTab()
      }
      .tabBar(this.TabBarBuilder('联系人', '👤'))
    }
    .onChange((index: number) => {
      this.currentIndex = index;
    })
    .width('100%')
    .height('100%')
  }
}