'use strict';

const test = require('node:test');
const assert = require('node:assert');
const fs = require('fs');
const os = require('os');
const path = require('path');

const { BigMapService, TILE_PIXELS, DEFAULT_MAX_ZOOM } = require('../src/core/bigMapService');
const { defaultConfig } = require('../src/config/expansionConfig');

/** 造一张假的 PNG 内容（只需非空即可，服务端只做字节透传） */
function fakePng(size) {
  const buffer = Buffer.alloc(size || 64);
  buffer[0] = 0x89;
  buffer[1] = 0x50;
  return buffer;
}

/** 建一个使用临时缓存目录、带假 fetch 的大地图服务 */
function setup(options) {
  const opts = options || {};
  const cacheDir = fs.mkdtempSync(path.join(os.tmpdir(), 'autostore-bigmap-'));
  const config = defaultConfig();
  Object.assign(config.bigMap, opts.bigMap || {});
  const calls = [];
  const fetchImpl = opts.fetchImpl || (async (url) => {
    calls.push(url);
    if (opts.failAll) return { ok: false, status: 404, arrayBuffer: async () => new ArrayBuffer(0) };
    const data = fakePng(opts.tileSize || 64);
    return { ok: true, status: 200, arrayBuffer: async () => data.buffer.slice(data.byteOffset, data.byteOffset + data.length) };
  });
  const service = new BigMapService(config, null, {
    baseUrl: 'http://bgjq.simpfun.cn',
    world: 'minecraft_overworld',
    cacheDir,
    fetchImpl
  });
  return { service, config, cacheDir, calls };
}

test('坐标系：最大层级 1 方块 = 1 像素，逐级翻倍', () => {
  const { service } = setup();
  assert.strictEqual(service.maxZoom, DEFAULT_MAX_ZOOM);
  assert.strictEqual(service.blocksPerTile(3), TILE_PIXELS, '最大层级每张瓦片覆盖 512 方块');
  assert.strictEqual(service.blocksPerTile(2), TILE_PIXELS * 2);
  assert.strictEqual(service.blocksPerTile(1), TILE_PIXELS * 4);
  assert.strictEqual(service.blocksPerTile(0), TILE_PIXELS * 8, '层级 0 每张瓦片覆盖 4096 方块');
});

test('坐标系：王城 (10722, 1547) 落在 z=3 的瓦片 (20, 3) 内（对源站实测标定）', () => {
  const { service } = setup();
  const bounds = service.tileBlockBounds(3, 20, 3);
  assert.deepStrictEqual(bounds, { minBlockX: 10240, maxBlockX: 10752, minBlockZ: 1536, maxBlockZ: 2048 });
  assert.ok(10722 >= bounds.minBlockX && 10722 < bounds.maxBlockX);
  assert.ok(1547 >= bounds.minBlockZ && 1547 < bounds.maxBlockZ);
});

test('tileRange 覆盖 ±rangeBlocks：层级 0 全世界为 10×10=100 张', () => {
  const { service } = setup();
  const range = service.tileRange(0, 20480, 0, 0);
  assert.strictEqual(range.minX, -5);
  assert.strictEqual(range.maxX, 4);
  assert.strictEqual(range.minZ, -5);
  assert.strictEqual(range.maxZ, 4);
  assert.strictEqual(range.count, 100);
  // 瓦片范围必须完整覆盖 -20480..20480
  assert.strictEqual(range.minX * service.blocksPerTile(0), -20480);
  assert.strictEqual((range.maxX + 1) * service.blocksPerTile(0), 20480);
});

test('tileRange 支持以机器人位置为中心：图幅越小爬的瓦片越少', () => {
  const { service } = setup();
  // 层级 0 每张瓦片 4096 格：半径 20480 → 100 张，4096 → 4 张
  assert.strictEqual(service.tileRange(0, 20480, 0, 0).count, 100);
  assert.strictEqual(service.tileRange(0, 4096, 0, 0).count, 4);
  // 半径 1024 且中心落在某张瓦片正中（瓦片 4 覆盖 16384..20480，中心 18432）→ 只要 1 张
  const centered = service.tileRange(0, 1024, 18432, 18432);
  assert.strictEqual(centered.count, 1);
  assert.strictEqual(centered.minX, 4);
  assert.strictEqual(centered.minZ, 4);
  assert.strictEqual(centered.centerBlockX, 18432);
  // 该瓦片必须真的覆盖机器人坐标
  const bounds = service.tileBlockBounds(0, centered.minX, centered.minZ);
  assert.ok(18432 >= bounds.minBlockX && 18432 < bounds.maxBlockX);
  assert.ok(18432 >= bounds.minBlockZ && 18432 < bounds.maxBlockZ);
});

test('tileRange 中心移到远处时瓦片下标整体平移，不再盯着世界原点', () => {
  const { service } = setup();
  const atOrigin = service.tileRange(0, 4096, 0, 0);
  const atBot = service.tileRange(0, 4096, 20000, -20000);
  assert.notStrictEqual(atOrigin.minX, atBot.minX);
  // 机器人所在的瓦片（正 X、负 Z 象限）必须落在范围内
  const tileX = Math.floor(20000 / 4096);
  const tileZ = Math.floor(-20000 / 4096);
  assert.ok(tileX >= atBot.minX && tileX <= atBot.maxX, '瓦片 X 下标应覆盖机器人');
  assert.ok(tileZ >= atBot.minZ && tileZ <= atBot.maxZ, '瓦片 Z 下标应覆盖机器人');
  assert.ok(tileX > 0 && tileZ < 0, '机器人位于正 X、负 Z 象限');
  const bounds = service.tileBlockBounds(0, tileX, tileZ);
  assert.ok(20000 >= bounds.minBlockX && 20000 < bounds.maxBlockX);
});

test('tileRange 缺省中心为世界原点', () => {
  const { service } = setup();
  const range = service.tileRange(0, 4096);
  assert.strictEqual(range.centerBlockX, 0);
  assert.strictEqual(range.centerBlockZ, 0);
});

test('tileUrl / tilePath 拼接源站地址与磁盘缓存路径', () => {
  const { service } = setup();
  assert.strictEqual(
    service.tileUrl(2, -3, 7),
    'http://bgjq.simpfun.cn/tiles/minecraft_overworld/2/-3_7.png'
  );
  assert.ok(service.tilePath(2, -3, 7).endsWith(path.join('minecraft_overworld', '2', '-3_7.png')));
});

test('getTile 首次回源并落盘，第二次命中磁盘不再回源', async () => {
  const { service, calls } = setup();
  const first = await service.getTile(1, 2, 3);
  assert.ok(first && first.length > 0);
  assert.strictEqual(calls.length, 1);

  // 清掉内存缓存，验证磁盘缓存生效
  service._memory.clear();
  const second = await service.getTile(1, 2, 3);
  assert.ok(second && second.length > 0);
  assert.strictEqual(calls.length, 1, '第二次不应再回源');
});

test('getTile 回源失败返回 null（控制台画占位色块）', async () => {
  const { service } = setup({ failAll: true });
  assert.strictEqual(await service.getTile(0, 0, 0), null);
});

test('crawlAll 批量爬取范围内全部瓦片并统计进度', async () => {
  const { service, calls } = setup({ bigMap: { rangeBlocks: 4096 } });
  const result = await service.crawlAll(0);
  // rangeBlocks=4096、层级 0 每张 4096 方块 → 2×2=4 张
  assert.strictEqual(result.total, 4);
  assert.strictEqual(result.done, 4);
  assert.strictEqual(result.failed, 0);
  assert.strictEqual(result.running, false);
  assert.strictEqual(calls.length, 4);
  assert.strictEqual(service.countCached(0), 4);
});

test('crawlAll 已缓存的瓦片不重复下载', async () => {
  const { service, calls } = setup({ bigMap: { rangeBlocks: 4096 } });
  await service.crawlAll(0);
  assert.strictEqual(calls.length, 4);
  await service.crawlAll(0);
  assert.strictEqual(calls.length, 4, '第二次爬取应全部命中缓存');
});

test('crawlAll 统计失败张数', async () => {
  const { service } = setup({ failAll: true, bigMap: { rangeBlocks: 4096 } });
  const result = await service.crawlAll(0);
  assert.strictEqual(result.total, 4);
  assert.strictEqual(result.done, 0);
  assert.strictEqual(result.failed, 4);
});

test('crawlAll 支持以指定中心爬取（只拉机器人周边那几张）', async () => {
  const { service, calls } = setup();
  const result = await service.crawlAll(0, {
    centerBlockX: 18432,
    centerBlockZ: 18432,
    rangeBlocks: 1024
  });
  assert.strictEqual(result.total, 1, '中心落在瓦片正中且半径 1024 时只需 1 张瓦片');
  assert.strictEqual(result.done, 1);
  assert.strictEqual(result.centerBlockX, 18432);
  assert.strictEqual(result.rangeBlocks, 1024);
  // 只请求了机器人所在的那一张，而不是世界原点附近
  assert.strictEqual(calls.length, 1);
  assert.ok(calls[0].includes('/4_4.png'), '实际请求的瓦片 URL：' + calls[0]);
});

test('snapshot 暴露坐标系、瓦片范围与缓存数量', () => {
  const { service } = setup({ bigMap: { rangeBlocks: 20480, zoom: 0 } });
  const snap = service.snapshot();
  assert.strictEqual(snap.world, 'minecraft_overworld');
  assert.strictEqual(snap.tilePixels, TILE_PIXELS);
  assert.strictEqual(snap.blocksPerTile, 4096);
  assert.strictEqual(snap.tiles.count, 100);
  assert.strictEqual(snap.cached, 0);
  assert.ok(snap.source.tileUrlTemplate.includes('{z}/{x}_{y}.png'));
});

test('snapshot 接受中心参数，瓦片范围随机器人位置变化', () => {
  const { service } = setup({ bigMap: { rangeBlocks: 1024, zoom: 0 } });
  const atOrigin = service.snapshot({ centerBlockX: 0, centerBlockZ: 0 });
  const atBot = service.snapshot({ centerBlockX: 18432, centerBlockZ: 18432 });
  assert.strictEqual(atBot.tiles.count, 1, '中心落在瓦片正中时只要 1 张');
  assert.notStrictEqual(atOrigin.tiles.minX, atBot.tiles.minX, '中心不同，瓦片下标必须不同');
  assert.strictEqual(atBot.tiles.centerBlockX, 18432);
  assert.strictEqual(atBot.tiles.minX, 4);
});

test('clearCache 清空磁盘与内存缓存', async () => {
  const { service } = setup({ bigMap: { rangeBlocks: 4096 } });
  await service.crawlAll(0);
  assert.strictEqual(service.countCached(0), 4);
  const removed = service.clearCache();
  assert.strictEqual(removed, 4);
  assert.strictEqual(service.countCached(0), 0);
  assert.strictEqual(service._memory.size, 0);
});

test('配置里 zoom 大于 maxZoom 时被钳制（避免爬到源站不存在的瓦片）', () => {
  const { service, config } = setup({ bigMap: { zoom: 7, maxZoom: 3 } });
  // 直接走一次配置归一化，验证钳制逻辑
  const { normalizeConfig } = require('../src/config/expansionConfig');
  const normalized = normalizeConfig(config);
  assert.strictEqual(normalized.bigMap.zoom, 3);
  assert.strictEqual(service.maxZoom, 3);
});