import { artifacts } from '../artifacts.svelte';
import { place } from '../format';
import { SvelteMap } from 'svelte/reactivity';
import { sessions } from '../sessions.svelte';
import { childrenOf, windows, type Tile } from './tree';

type Shown = { type: string; data: Record<string, unknown> };

/** Where each live shell says it is, by terminal id: the window title and its tab read the same of it. */
export const shells = new SvelteMap<string, { cwd: string; shell: string }>();

/** What a tab calls a window, from its record alone: an inactive tab's window is not mounted to ask. */
export function windowTitle(window: Shown): string {
  const data = window.data;
  const session = typeof data.sessionId === 'string' ? sessions.byId.get(data.sessionId) : undefined;
  const name = session?.name || 'untitled session';
  switch (window.type) {
    case 'session':
      return name;
    case 'artifact':
      return (typeof data.artifact === 'string' && artifacts.get(data.artifact)?.title) || 'artifact';
    case 'pty': {
      const live = typeof data.terminalId === 'string' ? shells.get(data.terminalId) : undefined;
      const cwd = live?.cwd || (typeof data.cwd === 'string' ? data.cwd : '');
      return `terminal · ${data.title || (cwd ? place(cwd) : live?.shell || 'shell')}`;
    }
    case 'chip':
      return data.chip === 'model' ? 'context' : String(data.chip);
    case 'note':
      return 'note';
    default:
      return `${window.type} · ${name}`;
  }
}

/** What a tab calls window `id` of `records`, which may have closed. */
export function windowName(id: string, records: Record<string, Shown>): string {
  return records[id] ? windowTitle(records[id]) : 'window';
}

/** What a tab or a section is called: its name, else its window's title, else what it holds. */
export function tileTitle(tile: Tile, records: Record<string, Shown>): string {
  if (tile.name) return tile.name;
  if (tile.kind === 'leaf') return windowName(tile.window, records);
  if (tile.kind !== 'canvas') return childrenOf(tile).map((child) => tileTitle(child, records)).join(', ');
  const count = windows(tile).length;
  return count ? `canvas · ${count} ${count === 1 ? 'window' : 'windows'}` : 'empty canvas';
}