/*
 * AgentMail 鸿蒙客户端 — 收件箱页
 * GET /me/inbox 分页，列表展示邮件摘要
 */
import { ApiClient, ApiError } from '../api/ApiClient';
import { Theme } from '../common/Theme';
import { MailApi } from '../api/MailApi';
import { MailSummary, Me } from '../model/Models';
import { router } from '@kit.ArkUI';
import { AmIcon } from '../common/Icons';
import { LIST_FADE_LENGTH } from '../model/NavItems';
import { LengthMetrics } from '@kit.ArkUI';
import { Insets, KEY_WINDOW_INSETS, topInset } from '../model/WindowInsets';

@Entry
@Component
struct InboxPage {
  @State mails: MailSummary[] = [];
  /**
   * 窗口避让区 —— 由 `EntryAbility.setupFullScreenWindow` 写进 AppStorage。
   *
   * ★ 推上来的页**也要**消费它：`setWindowLayoutFullScreen(true)` 是**窗口级**的，
   *   一旦设上，这个窗口里**所有**用 `router.pushUrl` 推上来的页都从 y=0 开始画。
   *   本页顶栏原来贴 y=0 ⇒ 全屏后「取消/发送」会与时钟、wifi/电量图标重叠
   *   （2026-09-18 实测截图硬证）。只给 `MainPage` 加避让就是把"黑边"换成
   *   "顶栏被状态栏压住"，同属只做一半。
   */
  @StorageLink(KEY_WINDOW_INSETS) windowInsets: Insets = new Insets();

  @State loading: boolean = false;
  @State limit: number = 20;
  @State total: number = 0;
  @State unread: number = 0;
  @State me: Me = new Me();
  @State error: string = '';

  private client: ApiClient | null = null;
  private mailApi: MailApi | null = null;

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

  async loadInbox(): Promise<void> {
    const c: ApiClient | null = this.client;
    const m: MailApi | null = this.mailApi;
    if (c === null || m === null) {
      return;
    }
    this.loading = true;
    this.error = '';
    try {
      const resp = await m.inbox('all', this.limit);
      this.mails = resp.mails;
      this.total = resp.total;
      // 客户端统计未读（API 未提供顶层 unread）
      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;
    }
  }

  build() {
    Column() {
      // 顶栏
      Row() {
        Text('收件箱')
          .fontSize(20).fontWeight(FontWeight.Bold).fontColor(Theme.textPrimary)
        Blank()
        if (this.unread > 0) {
          Text(this.unread + ' 未读')
            .fontSize(13).fontColor(Theme.surface)
            .backgroundColor(Theme.danger)
            .borderRadius(10)
            .padding({ left: 8, right: 8, top: 2, bottom: 2 })
        }
      }
      /* 高度与 padding-top 一起加避让 —— 理由见 `ComposePage` 顶栏（同形状） */
      .width('100%')
      .height(56 + topInset(this.windowInsets))
      .padding({ left: 16, right: 16, top: topInset(this.windowInsets) })
      .backgroundColor(Theme.surface)

      // 列表
      if (this.loading) {
        Column() {
          LoadingProgress().width(40).height(40)
          Text('加载中…').fontSize(14).fontColor(Theme.textSubtle).margin({ top: 8 })
        }
        .width('100%').height('80%')
        .justifyContent(FlexAlign.Center)
      } else if (this.error.length > 0) {
        Column() {
          Text(this.error).fontSize(14).fontColor(Theme.danger)
          Button('重试').margin({ top: 12 }).onClick(() => { this.loadInbox(); })
        }
        .width('100%').height('80%')
        .justifyContent(FlexAlign.Center)
      } else if (this.mails.length === 0) {
        Column() {
          Text('收件箱为空').fontSize(16).fontColor(Theme.textSubtle)
        }
        .width('100%').height('80%')
        .justifyContent(FlexAlign.Center)
      } else {
        List({ space: 1 }) {
          ForEach(this.mails, (mail: MailSummary) => {
            ListItem() {
              this.MailItem(mail)
            }
            .height(80)
            .backgroundColor(mail.status === 'unread' ? Theme.accentSoft : Theme.surface)
            .onClick(() => {
              this.getUIContext().getRouter().pushUrl({
                url: 'pages/MailDetailPage',
                params: { mail_id: mail.mail_id }
              });
            })
          }, (mail: MailSummary) => mail.mail_id)
        }
        .width('100%')
        .layoutWeight(1)
        /* 上下边缘渐隐（2026-09-17 补：原先漏了，同一次滚动里只有部分是渐隐） */
        .fadingEdge(true, { fadingEdgeLength: LengthMetrics.vp(LIST_FADE_LENGTH) })
        .divider({ strokeWidth: 1, color: Theme.border, startMargin: 16, endMargin: 16 })
      }

      // 底部 Tab 栏（预留系统导航栏空间）
      Column() {
        Row() {
          Column() {
            AmIcon({ iconName: 'inbox', iconSize: 20, iconColor: Theme.accent })
            Text('收件箱').fontSize(11).fontColor(Theme.accent)
          }
          .layoutWeight(1).height('100%')
          .justifyContent(FlexAlign.Center)
          .backgroundColor(Theme.accentSoft)

          Column() {
            AmIcon({ iconName: 'chatBubble', iconSize: 20, iconColor: Theme.textMuted })
            Text('会话').fontSize(11).fontColor(Theme.textMuted)
          }
          .layoutWeight(1).height('100%')
          .justifyContent(FlexAlign.Center)
          .onClick(() => {
            this.getUIContext().getRouter().pushUrl({ url: 'pages/SessionsPage' });
          })

          Column() {
            AmIcon({ iconName: 'contacts', iconSize: 20, iconColor: Theme.textMuted })
            Text('联系人').fontSize(11).fontColor(Theme.textMuted)
          }
          .layoutWeight(1).height('100%')
          .justifyContent(FlexAlign.Center)
        }
        .width('100%').height(56)
        .backgroundColor(Theme.surface)
      }
      .width('100%')
    }
    .width('100%').height('100%')
    .backgroundColor(Theme.pageBg)
  }

  @Builder
  MailItem(mail: MailSummary) {
    Row() {
      // 未读圆点
      Column() {
        if (mail.status === 'unread') {
          Circle({ width: 8, height: 8 }).fill(Theme.accent)
        }
      }
      .width(20).height('100%')
      .justifyContent(FlexAlign.Center)

      // 正文
      Column() {
        Row() {
          Text(mail.from_name).fontSize(14).fontWeight(mail.is_read ? FontWeight.Normal : FontWeight.Bold).fontColor(Theme.textPrimary)
          Blank()
          Text(mail.created_at).fontSize(11).fontColor(Theme.textSubtle)
        }
        .width('100%')

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

      // 附件图标
      if (mail.has_attachments) {
        AmIcon({ iconName: 'paperclip', iconSize: 14, iconColor: Theme.textMuted }).margin({ right: 8 })
      }

      // 权限档位徽标
      if (mail.permission_mode.length > 0) {
        Text(mail.permission_mode)
          .fontSize(10).fontColor(Theme.textMuted)
          .backgroundColor(Theme.border).borderRadius(4)
          .padding({ left: 4, right: 4, top: 1, bottom: 1 })
      }
    }
    .width('100%').height('100%')
    .padding({ left: 12, right: 12 })
    .alignItems(VerticalAlign.Center)
  }
}