const axios = require("axios");

function resolveConfig(bru) {
  return {
    baseUrl: bru.getEnvVar("baseUrl") || bru.getVar("baseUrl"),
    playerId: bru.getEnvVar("playerId") || bru.getVar("playerId"),
    jsonHeaders: { headers: { "Content-Type": "application/json" } },
  };
}

function inventoryUrl(baseUrl, playerId) {
  return `${baseUrl}/game/players/${playerId}/inventory`;
}

function sumItemQuantity(inventory, itemId) {
  const slots = [...inventory.bagSlots, ...inventory.equipmentSlots];
  return slots
    .filter((slot) => slot.itemId === itemId)
    .reduce((total, slot) => total + slot.quantity, 0);
}

async function getInventory(bru) {
  const { baseUrl, playerId } = resolveConfig(bru);
  const response = await axios.get(inventoryUrl(baseUrl, playerId));
  if (response.status !== 200) {
    throw new Error(`GET inventory failed: ${response.status}`);
  }

  return response.data;
}

async function postMutation(bru, body) {
  const { baseUrl, playerId, jsonHeaders } = resolveConfig(bru);
  return axios.post(inventoryUrl(baseUrl, playerId), body, jsonHeaders);
}

async function ensureItemQuantity(bru, itemId, minQuantity) {
  const inventory = await getInventory(bru);
  const current = sumItemQuantity(inventory, itemId);
  if (current >= minQuantity) {
    return current;
  }

  const response = await postMutation(bru, {
    schemaVersion: 1,
    mutationKind: "add",
    itemId,
    quantity: minQuantity - current,
  });
  if (response.status !== 200 || response.data?.applied !== true) {
    throw new Error(
      `seed add ${itemId} failed: ${response.status} ${JSON.stringify(response.data)}`,
    );
  }

  const after = await getInventory(bru);
  return sumItemQuantity(after, itemId);
}

async function clearInventory(bru) {
  for (let pass = 0; pass < 32; pass += 1) {
    const inventory = await getInventory(bru);
    const totals = new Map();
    for (const slot of [...inventory.bagSlots, ...inventory.equipmentSlots]) {
      if (!slot.itemId || slot.quantity <= 0) {
        continue;
      }
      totals.set(slot.itemId, (totals.get(slot.itemId) ?? 0) + slot.quantity);
    }
    if (totals.size === 0) {
      return;
    }

    for (const [itemId, quantity] of totals) {
      const response = await postMutation(bru, {
        schemaVersion: 1,
        mutationKind: "remove",
        itemId,
        quantity,
      });
      if (response.status !== 200 || response.data?.applied !== true) {
        throw new Error(
          `clear inventory remove ${itemId} failed: ${response.status} ${JSON.stringify(response.data)}`,
        );
      }
    }
  }

  throw new Error("clearInventory: bag still not empty after removal passes");
}

module.exports = {
  sumItemQuantity,
  getInventory,
  postMutation,
  ensureItemQuantity,
  clearInventory,
};