import type { Article, Feed } from '../../db/schema';

export type Panel = 'feeds' | 'articles' | 'reader';
export type Overlay = 'none' | 'help' | 'search' | 'addFeed' | 'editFeed' | 'confirm' | 'update' | 'hint';

export interface HintTarget {
  url: string;
  label: string;
}
export type LayoutMode = 'wide' | 'medium' | 'narrow';
export type SortOrder = 'newest' | 'oldest' | 'title';

export interface UpdateInfo {
  packageName: string;
  currentVersion: string;
  latestVersion: string;
}

export interface FeedWithCount extends Feed {
  unreadCount: number;
}

export interface ArticleWithFeed extends Article {
  feed?: Feed;
}

export interface CategoryState {
  name: string;
  collapsed: boolean;
  feeds: FeedWithCount[];
  totalUnread: number;
}

export interface FetchProgress {
  current: number;
  total: number;
  feedTitle?: string;
}

export interface AppState {
  // Layout
  activePanel: Panel;
  layoutMode: LayoutMode;
  overlay: Overlay;
  feedPanelWidth: number | null; // null = auto, number = user-set columns
  articlePanelWidth: number | null; // null = auto, number = user-set columns (wide mode)

  // Data
  feeds: FeedWithCount[];
  categories: CategoryState[];
  articles: ArticleWithFeed[];
  selectedArticle: ArticleWithFeed | null;

  // Selection
  selectedFeedId: number | null; // null = "All Articles"
  selectedFeedType: 'all' | 'starred' | 'feed';
  feedListIndex: number;
  articleListIndex: number;

  // Filters
  showUnreadOnly: boolean;
  sortOrder: SortOrder;
  searchQuery: string;

  // Stats
  totalUnread: number;
  totalStarred: number;
  lastFetchedAt: Date | null;

  // UI state
  loading: boolean;
  fetchProgress: FetchProgress | null;
  confirmAction: ConfirmAction | null;
  error: string | null;
  editingFeed: FeedWithCount | null;
  updateInfo: UpdateInfo | null;

  // Hint mode (vimium-style link picker in reader). hintTargets is empty
  // unless overlay === 'hint'; hintBuffer accumulates keypresses until a
  // label resolves or fails to match any prefix.
  hintTargets: HintTarget[];
  hintBuffer: string;
}

export interface ConfirmAction {
  message: string;
  onConfirm: () => void | Promise<void>;
}

export type Action =
  | { type: 'SET_PANEL'; panel: Panel }
  | { type: 'SET_LAYOUT_MODE'; mode: LayoutMode }
  | { type: 'SET_OVERLAY'; overlay: Overlay }
  | { type: 'SET_FEEDS'; feeds: FeedWithCount[]; categories: CategoryState[] }
  | { type: 'SET_ARTICLES'; articles: ArticleWithFeed[] }
  | { type: 'SET_SELECTED_ARTICLE'; article: ArticleWithFeed | null }
  | { type: 'SELECT_FEED'; feedId: number | null; feedType: 'all' | 'starred' | 'feed' }
  | { type: 'SET_FEED_LIST_INDEX'; index: number }
  | { type: 'SET_ARTICLE_LIST_INDEX'; index: number }
  | { type: 'TOGGLE_UNREAD_FILTER' }
  | { type: 'CYCLE_SORT_ORDER' }
  | { type: 'SET_SEARCH_QUERY'; query: string }
  | { type: 'SET_STATS'; unread: number; starred: number; lastFetchedAt: Date | null }
  | { type: 'SET_LOADING'; loading: boolean }
  | { type: 'SET_FETCH_PROGRESS'; progress: FetchProgress | null }
  | { type: 'SET_CONFIRM'; action: ConfirmAction | null }
  | { type: 'SET_ERROR'; error: string | null }
  | { type: 'SET_EDITING_FEED'; feed: FeedWithCount | null }
  | { type: 'TOGGLE_CATEGORY'; categoryName: string }
  | { type: 'UPDATE_ARTICLE'; articleId: number; changes: Partial<Article> }
  | { type: 'SET_FEED_PANEL_WIDTH'; width: number | null }
  | { type: 'SET_ARTICLE_PANEL_WIDTH'; width: number | null }
  | { type: 'SET_UPDATE_INFO'; info: UpdateInfo | null }
  | { type: 'ENTER_HINT_MODE'; targets: HintTarget[] }
  | { type: 'APPEND_HINT_KEY'; key: string }
  | { type: 'EXIT_HINT_MODE' };

export const initialState: AppState = {
  activePanel: 'feeds',
  layoutMode: 'wide',
  overlay: 'none',
  feedPanelWidth: null,
  articlePanelWidth: null,
  feeds: [],
  categories: [],
  articles: [],
  selectedArticle: null,
  selectedFeedId: null,
  selectedFeedType: 'all',
  feedListIndex: 0,
  articleListIndex: 0,
  showUnreadOnly: false,
  sortOrder: 'newest',
  searchQuery: '',
  totalUnread: 0,
  totalStarred: 0,
  lastFetchedAt: null,
  loading: true,
  fetchProgress: null,
  confirmAction: null,
  error: null,
  editingFeed: null,
  updateInfo: null,
  hintTargets: [],
  hintBuffer: '',
};