frontend/src/lib/stores/game.ts

import { writable, derived } from 'svelte/store';
import type { GameState, PlayerState, Room, Unit, Building } from '$lib/types';
import { UNIT_SUPPLY_COST, BUILDING_SUPPLY_PROVIDED } from '$lib/types';

// ── Session ──────────────────────────────────────────────────────────────────
export const myPlayerId   = writable<string | null>(null);
export const playerName   = writable<string>('');
export const roomState    = writable<Room | null>(null);
export const roomId       = writable<string | null>(null);

// ── Game ─────────────────────────────────────────────────────────────────────
export const gameState    = writable<GameState | null>(null);
export const winnerId     = writable<string | null>(null);
export const isTutorial   = writable<boolean>(false);

// ── UI ───────────────────────────────────────────────────────────────────────
export const selectedUnit     = writable<Unit | null>(null);
export const selectedBuilding = writable<Building | null>(null);
export const mapViewport      = writable<{ vx: number; vy: number; vw: number; vh: number }>({ vx: 0, vy: 0, vw: 40, vh: 40 });
export const mapVisibleCells  = writable<Set<string>>(new Set());
export const mapExploredCells = writable<Set<string>>(new Set());
/** When set, main map recenters on (cx, cy); consumed by Map.svelte */
export const mapCenterRequest = writable<{ cx: number; cy: number } | null>(null);
export const voiceStatus      = writable<'idle' | 'recording' | 'processing'>('idle');
export const lastTranscription = writable<string>('');
export const lastFeedback      = writable<string>('');
export const feedbackLevel     = writable<'ok' | 'warning' | 'error'>('ok');
/**
 * Progressive map texture URL.
 * Starts null → set to MAP_quarter blob → MAP_half blob
 * by the landing-page preloader. Map.svelte falls back to the direct URL
 * if this is still null (e.g. user navigated directly to /game).
 */
export const mapTextureUrl = writable<string | null>(null);

// ── Derived ──────────────────────────────────────────────────────────────────

export const myPlayer = derived(
  [gameState, myPlayerId],
  ([$gs, $id]): PlayerState | null => {
    if (!$gs || !$id) return null;
    return $gs.players[$id] ?? null;
  }
);

export const enemyPlayer = derived(
  [gameState, myPlayerId],
  ([$gs, $id]): PlayerState | null => {
    if (!$gs || !$id) return null;
    return Object.values($gs.players).find((p) => p.player_id !== $id) ?? null;
  }
);

/** Supply computed client-side from actual units + active buildings. */
export const mySupply = derived(
  [gameState, myPlayerId],
  ([$gs, $id]): { used: number; max: number } => {
    if (!$gs || !$id) return { used: 0, max: 0 };
    const player = $gs.players[$id];
    if (!player) return { used: 0, max: 0 };

    const used = Object.values(player.units).reduce(
      (sum, u) => sum + (UNIT_SUPPLY_COST[u.unit_type] ?? 0),
      0
    );
    const max = Object.values(player.buildings).reduce(
      (sum, b) =>
        b.status === 'constructing' || b.status === 'destroyed'
          ? sum
          : sum + (BUILDING_SUPPLY_PROVIDED[b.building_type] ?? 0),
      0
    );
    return { used, max };
  }
);

export const allUnitsFlat = derived(gameState, ($gs) => {
  if (!$gs) return [];
  return Object.values($gs.players).flatMap((p) =>
    Object.values(p.units).map((u) => ({ unit: u, isOwn: false }))
  );
});