/**
 * sockets/combat.js – Server-seitige Kampfphasen-Logik für 1v1
 *
 * ZWEI PHASEN PRO ZUG:
 *
 *   Phase 1 – BEWEGUNG (nur Karten des aktiven Spielers, vorderste zuerst)
 *   Phase 2 – ANGRIFF  (nur Karten des aktiven Spielers, Slot 11→1)
 */

'use strict';

/**
 * @param {Object} boardState  – wird in-place verändert
 * @param {string} leftSlot    – 'player1' oder 'player2' (wer links steht)
 * @param {string} activeSlot  – 'player1' oder 'player2' (wer gerade am Zug ist)
 * @returns {Array}            – geordnete Event-Liste für den Client
 */
function runCombatPhase(boardState, leftSlot, activeSlot) {
  const events = [];

  /* ════════════════════════════════════════════════════════
     PHASE 1: BEWEGUNG
     Nur Karten des aktiven Spielers bewegen sich.
     Vorderste Karte zuerst → Kette kann aufrücken.
       Linker  Spieler (dir +1): höchste Slot-Zahl zuerst
       Rechter Spieler (dir -1): niedrigste Slot-Zahl zuerst
  ════════════════════════════════════════════════════════ */

  const myCards = [];

  for (let slotIndex = 1; slotIndex <= 11; slotIndex++) {
    for (const row of ['row1', 'row2']) {
      const slotId = `${row}-slot-${slotIndex}`;
      if (boardState[slotId]?.owner === activeSlot) {
        myCards.push(slotId);
      }
    }
  }

  const isActiveLeft = activeSlot === leftSlot;
  const dir          = isActiveLeft ? 1 : -1;

  // Vorderste Karte zuerst
  myCards.sort((a, b) => {
    const ia = parseInt(a.split('-slot-')[1], 10);
    const ib = parseInt(b.split('-slot-')[1], 10);
    return isActiveLeft ? ib - ia : ia - ib; // links: 11→1 | rechts: 1→11
  });

  for (const startSlotId of myCards) {
    const entry = boardState[startSlotId];
    if (!entry) continue;

    const { card } = entry;
    const row      = startSlotId.split('-slot-')[0];
    const race     = card.race ?? 0;

    let currentPos    = parseInt(startSlotId.split('-slot-')[1], 10);
    let currentSlotId = startSlotId;

    for (let step = 0; step < race; step++) {
      const nextPos = currentPos + dir;
      if (nextPos < 1 || nextPos > 11) break;

      const nextSlotId = `${row}-slot-${nextPos}`;
      if (boardState[nextSlotId]) break; // eigene oder feindliche Karte blockiert

      delete boardState[currentSlotId];
      boardState[nextSlotId] = entry;

      events.push({ type: 'move', from: currentSlotId, to: nextSlotId, owner: activeSlot });

      currentSlotId = nextSlotId;
      currentPos    = nextPos;
    }
  }

  /* ════════════════════════════════════════════════════════
     PHASE 2: ANGRIFF
     Nur Karten des aktiven Spielers greifen an.
     Feste Reihenfolge: Slot 11 → 1, row1 vor row2.
     Snapshot nach den Bewegungen.
  ════════════════════════════════════════════════════════ */

  const attackOrder = [];
  for (let slotIndex = 11; slotIndex >= 1; slotIndex--) {
    for (const row of ['row1', 'row2']) {
      const slotId = `${row}-slot-${slotIndex}`;
      if (boardState[slotId]?.owner === activeSlot) {
        attackOrder.push(slotId);
      }
    }
  }

  for (const slotId of attackOrder) {
    const entry = boardState[slotId];
    if (!entry) continue;

    const { card }   = entry;
    const row        = slotId.split('-slot-')[0];
    const currentPos = parseInt(slotId.split('-slot-')[1], 10);
    const range      = card.range ?? 0;

    for (let r = 1; r <= range; r++) {
      const targetPos    = currentPos + dir * r;
      if (targetPos < 1 || targetPos > 11) break;

      const targetSlotId = `${row}-slot-${targetPos}`;
      const target       = boardState[targetSlotId];

      if (!target) continue;                    // leeres Feld → weiter scannen
      if (target.owner === activeSlot) continue; // eigene Karte → Range geht hindurch

      // Feindliche Karte → Angriff
      const atk = card.attack ?? 0;
      target.card = { ...target.card, defends: (target.card.defends ?? 0) - atk };

      events.push({
        type        : 'attack',
        from        : slotId,
        to          : targetSlotId,
        damage      : atk,
        remainingDef: target.card.defends,
      });

      if (target.card.defends <= 0) {
        delete boardState[targetSlotId];
        events.push({ type: 'die', slotId: targetSlotId });
      }

      break; // nur erste feindliche Karte angreifen
    }
  }

  return events;
}

module.exports = { runCombatPhase };