// 玩家：还原 IWBT 的硬核手感 —— 松手即停、无加速、可变跳跃高度、二段跳
import { TILE, clamp, sgn, overlap } from './util.js';
import { Input } from './input.js';
import { sfx } from './audio.js';
import * as S from './sprites.js';
import { T } from './level.js';

export const PHY = {
  GRAV: 0.25,        // 上升段重力：小 = 跳跃飘
  GRAV_FALL: 0.32,   // 下落段重力：小 = 下坠轻、飘落感（0.35→0.32，用户反馈"下落有点沉"）
  GRAV_DJ: 0.35,     // 二段跳上升段专属重力：比 GRAV 稍重——初速 6.7 与一段 6.6 一致，配 0.35 才能又冲（不起悬停）又只有 4.5 格总高
  MAXFALL: 9,
  JUMP: 6.6,
  DJUMP: 6.7,       // 二段跳冲量：起跳初速与一段 JUMP 6.6 几乎一致（起跳"嘭"感同款）；顶点接二段总高 = 4.51 格
  DJ_INERTIA: 0,     // 二段跳时下落速度对冲量的抵消比例：0=任何时机接二段都满力起跳（初速恒 -DJUMP，同 IWBT 原版），
                    // 1=全额抵消（旧 bug：顶点晚几帧接二段直接归零）。0.35/0.5 都被用户反馈"好沉+短"——起跳初速被下落速度
                    // 吃掉才是"沉"的根源（初速从 6.7 掉到 3~4，起跳那一下没劲），与上升重力无关。
  HSPD: 2.6,
  WATER_GRAV: 0.16,
  WATER_FALL: 2.6,
  WATER_RISE: 0.42,
  ICE_ACC: 0.18,
  ICE_FRIC: 0.07,
  // 滑出冰块后的惯性：空中几乎不损失，地面缓慢收住
  SLIDE_FRIC: 0.12,      // 非冰地面上收住惯性的摩擦
  SLIDE_AIR: 0.02,       // 空中惯性衰减（≈0，滑出冰块边缘能一路飞出去）
  SLIDE_EASE: 0.14,      // 超速滑行时按住同向键，收敛回正常走速的速度
  SLIDE_BRAKE: 0.45,     // 滑行中按反向键的刹车
  SLIDE_MIN: 0.35,       // 冰面上攒到多大速度才算进入滑行状态
  SLIDE_STOP: 0.05,      // 低于此速度惯性结束
  ICE_TOP: 1.6,          // 冰面最高速度 = HSPD × ICE_TOP（调大=冰上能滑得更快，留更猛的惯性）
};

export class Player {
  constructor(level) {
    this.level = level;
    // IWBT 官方判定盒：11×21 像素（比精灵视觉略小，支持像素级擦弹/贴刺）
    this.w = 11; this.h = 21;
    this.reset(true);
  }

  reset(full) {
    const sp = full ? this.level.spawn : (this.savePoint || this.level.spawn);
    this.x = sp.x; this.y = sp.y;
    this.vx = 0; this.vy = 0;
    this.jumps = 0;
    this.djUp = false;
    this.grounded = false;
    this.facing = 1;
    this.alive = true;
    this.dead = false;
    this.deadT = 0;
    this.inWater = false;
    this.animT = 0;
    this.shootCool = 0;
    this.mover = null;
    this.sliding = false;        // 冰面滑行惯性状态：离开冰块后仍保留
    this.justRespawned = false;  // 本帧刚复活（供镜头瞬移）
    if (full) {
      this.hasGun = !!this.level.data.startGun;
      this.apples = 0;
      this.savePoint = null;
      this.saveIdx = 0;
    }
  }

  get cx() { return this.x + this.w / 2; }
  get cy() { return this.y + this.h / 2; }

  // 死亡：不播任何死亡动画（无等待、无镜头演出），只留音效、死亡计数，
  // 以及在死亡地点落一处 IWBTG 风格的血迹（由 Level 常驻渲染，复活后仍在）。
  kill() {
    if (this.dead || !this.alive) return;
    this.dead = true; this.alive = false; this.deadT = 0;
    this.vx = 0; this.vy = 0; this.sliding = false;
    sfx.death();
    this.level.addDeathMark(this.cx, this.cy);
    if (this.onDeath) this.onDeath();
  }

  respawn() {
    this.dead = false; this.alive = true;
    const L = this.level;
    const sp = this.savePoint || L.spawn;
    this.x = sp.x; this.y = sp.y;
    this.vx = 0; this.vy = 0; this.jumps = 0;
    this.djUp = false;
    this.shootCool = 0; this.sliding = false;
    this.deadT = 0;
    // 安全兜底：万一重生点被地形/消失块堵住，向上顶出，别一复活就卡死
    let guard = 0;
    while (L.solidRect(this.x, this.y, this.w, this.h) && guard++ < 48) this.y -= 2;
    L.softReset();
    this.justRespawned = true;      // 供 main.js 把镜头直接吸附到重生点
  }

  // ---------------- 每帧更新 ----------------
  update(dt) {
    const L = this.level;
    this.animT++;
    if (this.shootCool > 0) this.shootCool--;

    // 上一帧/外部（R 键自杀、假存档）触发的死亡：立刻复活，不留死亡动画
    if (this.dead) this.respawn();

    const inWater = L.waterRect(this.x + 2, this.y + 4, this.w - 4, this.h - 4);
    if (inWater && !this.inWater) sfx.splash();
    this.inWater = inWater;

    // ---- 水平输入（IWBT：普通地面瞬时、无惯性；冰面打滑并保留惯性）----
    const moveL = Input.is('left'), moveR = Input.is('right');
    const onIce = this.grounded && L.iceAtBottom(this.x, this.y, this.w, this.h);
    let target = 0;
    if (moveL && !moveR) target = -PHY.HSPD;
    else if (moveR && !moveL) target = PHY.HSPD;

    const ICE_MAX = PHY.HSPD * PHY.ICE_TOP;
    const decel = f => {
      if (Math.abs(this.vx) <= f) this.vx = 0;
      else this.vx -= sgn(this.vx) * f;
    };

    if (onIce) {
      // 冰面：加速/减速都很慢，速度上限也更高
      if (target !== 0) this.vx += sgn(target) * PHY.ICE_ACC;
      else decel(PHY.ICE_FRIC);
      this.vx = clamp(this.vx, -ICE_MAX, ICE_MAX);
      // 攒出一定速度即进入「滑行」状态——这是惯性得以保留的关键
      if (Math.abs(this.vx) > PHY.SLIDE_MIN) this.sliding = true;
    } else if (this.sliding && Math.abs(this.vx) > PHY.SLIDE_STOP) {
      // 滑出冰块后：惯性依然保留 —— 空中几乎不衰减，地面才慢慢收住
      if (target !== 0) {
        const dir = sgn(this.vx);
        if (dir === 0 || sgn(target) === dir) {
          if (Math.abs(this.vx) >= PHY.HSPD) {
            // 还在超速滑行：同向按键只让它缓慢收敛回正常走速，不再继续加速
            this.vx -= dir * PHY.SLIDE_EASE;
            if (Math.abs(this.vx) < PHY.HSPD) { this.vx = target; this.sliding = false; }
          } else {
            this.vx = target;                        // 已低于走速：交还玩家控制
            this.sliding = false;
          }
        } else {
          this.vx -= dir * PHY.SLIDE_BRAKE;          // 反向按键：刹车，刹住后立刻反向
          if (sgn(this.vx) === sgn(target)) { this.vx = target; this.sliding = false; }
        }
        this.vx = clamp(this.vx, -ICE_MAX, ICE_MAX);
      } else {
        decel(this.grounded ? PHY.SLIDE_FRIC : PHY.SLIDE_AIR);
        if (this.vx === 0) this.sliding = false;
      }
      if (this.vx !== 0 && Math.abs(this.vx) < PHY.SLIDE_STOP) { this.vx = 0; this.sliding = false; }
    } else {
      // 常规地面/空中（非滑行）：IWBT 标准手感，松手即停、无惯性
      this.vx = target;
      this.sliding = false;
    }
    if (target !== 0) this.facing = sgn(target);

    // ---- 跳跃 ----
    if (inWater) {
      if (Input.is('jump')) this.vy -= PHY.WATER_RISE;
      if (Input.is('down')) this.vy += 0.25;
      this.vy = clamp(this.vy, -3.2, PHY.WATER_FALL);
      this.jumps = 0; this.djUp = false;
    } else {
      if (Input.hit('jump')) {
        if (this.grounded || this.jumps === 0) {
          this.vy = -PHY.JUMP; this.jumps = 1; this.grounded = false;
          // 不再做起跳拉伸：空中保持身体比例，避免跳跃时视觉上下晃动
          sfx.jump();
          L.particles.spawn(this.cx, this.y + this.h, 5,
            { colors: ['#fff', '#cfcfe0'], speed: 1.6, life: 16, size: 2, dir: -Math.PI / 2, spread: 2 });
        } else if (this.jumps === 1) {
          // 二段跳冲量叠减当前速度：上升中按 = 原版语义（直接获得 -DJUMP）；
          // 下落中按 = 下落惯性只抵消一部分冲量（DJUMP 前乘 DJ_INERTIA）——
          // 全额抵消会让"满力一段跳到顶点、晚几帧接二段"的二段塌到接近 0（非常短），
          // 只抵消一半则顶点附近接二段保持满力，摔得快时才明显变弱
          this.vy = Math.max(this.vy, 0) * PHY.DJ_INERTIA - PHY.DJUMP; this.jumps = 2;
          this.djUp = this.vy < 0;   // 二段上升段启用专属轻重力（与一段同款飘）
          sfx.djump();
          L.particles.spawn(this.cx, this.cy, 10,
            { colors: ['#fff', '#9ad8ff'], speed: 2.2, life: 20, size: 2, spread: Math.PI * 2 });
        }
      }
      // 可变跳跃高度
      if (!Input.is('jump') && this.vy < -3) this.vy = -3;
      // 上升轻、下落重：分手感。二段上升段用更轻的 GRAV_DJ（初速小，同款飘）
      this.vy = Math.min(this.vy + (this.vy < 0 ? (this.djUp ? PHY.GRAV_DJ : PHY.GRAV) : PHY.GRAV_FALL), PHY.MAXFALL);
      if (this.djUp && this.vy >= 0) this.djUp = false;   // 二段到顶，交回普通重力
    }

    // ---- 站在移动平台上则跟随 ----
    if (this.mover && !this.mover.gone) {
      this.x += this.mover.dx;
      this.y += this.mover.dy;
    }

    // ---- X 轴移动 ----
    const prevBottom = this.y + this.h;
    this.mover = null;
    let steps = Math.abs(this.vx);
    const dx = sgn(this.vx);
    while (steps > 0) {
      const m = Math.min(1, steps);
      if (!L.solidRect(this.x + dx * m, this.y, this.w, this.h)) { this.x += dx * m; steps -= m; }
      else break;
    }
    if (L.solidRect(this.x + dx, this.y, this.w, this.h) && Math.abs(this.vx) > 0) this.vx = 0;

    // ---- Y 轴移动 ----
    const dropThrough = Input.is('down');
    steps = Math.abs(this.vy);
    const dy = sgn(this.vy);
    let hitGround = false;
    while (steps > 0) {
      const m = Math.min(1, steps);
      const ny = this.y + dy * m;
      const solidHere = L.solidRect(this.x, ny, this.w, this.h, {
        prevBottom, dropThrough,
      });
      if (!solidHere) { this.y = ny; steps -= m; }
      else {
        if (dy > 0) hitGround = true;
        this.vy = 0;
        break;
      }
    }
    // 检查是否踩到移动平台
    for (const m of L.movers) {
      if (m.gone) continue;
      if (this.x + this.w > m.x && this.x < m.x + m.w) {
        if (this.y + this.h >= m.y - 2 && this.y + this.h <= m.y + m.h) {
          this.mover = m; hitGround = true;
        }
      }
    }

    const wasAir = !this.grounded;
    this.grounded = hitGround || (this.vy === 0 && L.solidRect(this.x, this.y + 1, this.w, this.h));
    if (this.grounded) {
      this.jumps = 0; this.djUp = false;
    }

    // ---- 滑行反馈：超速滑行（冰上，或刚滑出冰块仍带惯性）时脚下溅起冰屑 ----
    if (this.sliding && this.grounded && Math.abs(this.vx) > PHY.HSPD && this.animT % 5 === 0) {
      L.particles.spawn(this.cx - sgn(this.vx) * 5, this.y + this.h - 2, 2, {
        colors: ['#dff4ff', '#8fd8f0', '#fff'], speed: 1.1, life: 16, size: 2,
        dir: -Math.PI / 2, spread: 1.7, grav: 0.1,
      });
    }

    // ---- 边界 ----
    this.x = clamp(this.x, 0, L.pxW - this.w);
    if (this.y > L.pxH + 200) { this.kill(); if (this.dead) { this.respawn(); return; } }
    if (this.y < -300) { this.y = -300; this.vy = 0; }

    // ---- 致死：同帧立刻复活，画面上不留任何死亡状态 ----
    if (L.deadlyRect(this.x, this.y, this.w, this.h)) { this.kill(); if (this.dead) { this.respawn(); return; } }

    // ---- 射击 ----
    if (this.hasGun && Input.hit('shoot') && this.shootCool === 0 && L.bullets.length < 5) {
      this.shoot();
    }

    // ---- 实体交互 ----
    this.touchEntities();

    // ---- 消失方块踩踏 ----
    if (this.grounded) {
      const ty = Math.floor((this.y + this.h + 2) / TILE);
      for (let tx = Math.floor(this.x / TILE); tx <= Math.floor((this.x + this.w - 1) / TILE); tx++) {
        if (L.tiles[ty] && L.tiles[ty][tx] === T.VANISH && L.vanishState(tx, ty) === 0) {
          L.setVanish(tx, ty, 1);
          L.vanishT = L.vanishT || new Map();
          L.vanishT.set(ty * 1000 + tx, 0);
        }
      }
    }

    // 兜底：本帧内任何环节致死（如假存档）都立刻复活
    if (this.dead) this.respawn();
  }

  shoot() {
    const L = this.level;
    this.shootCool = 9;
    L.bullets.push({
      x: this.facing > 0 ? this.x + this.w - 2 : this.x - 6,
      y: this.y + 8, w: 10, h: 5,
      vx: 9 * this.facing, vy: 0, life: 130, dead: false,
    });
    sfx.shoot();
    L.particles.spawn(this.facing > 0 ? this.x + this.w : this.x, this.y + 10, 3,
      { colors: ['#fff6a0'], speed: 1.5, life: 10, size: 2 });
  }

  touchEntities() {
    const L = this.level;
    for (const e of L.entities) {
      if (e.dead) continue;
      // 存档点判定放宽 6px：跑得太快或从旁边擦过去也能吃到
      const hit = e.type === 'save'
        ? overlap({ x: this.x - 6, y: this.y - 6, w: this.w + 12, h: this.h + 12 }, e)
        : overlap(this, e);
      if (!hit) continue;
      switch (e.type) {
        case 'save':
          if (!e.active) {
            e.active = true;
            this.savePoint = { x: e.x + e.w / 2 - this.w / 2, y: e.y + e.h - this.h, face: (this.level.faceIndex ?? 0) };
            this.saveIdx = e.no || 1;
            sfx.save();
            L.particles.spawn(e.x + e.w / 2, e.y + e.h / 2, 18,
              { colors: ['#b06bff', '#fff', '#e5d0ff'], speed: 2.6, life: 30 });
            // 假存档：立刻复活回上一个存档点，不播死亡动画
            if (e.fake) { L.showToast('假的。', 90); this.kill(); if (this.dead) { this.respawn(); return; } }
          }
          break;
        case 'goal':
          if (!this.clearing) { this.clearing = true; if (this.onClear) this.onClear(); }
          break;
        case 'gun':
          if (!e.taken) {
            e.taken = true; this.hasGun = true;
            L.particles.spawn(e.x + e.w / 2, e.y + e.h / 2, 12, { colors: ['#dfe0f0', '#fff'], speed: 2.2, life: 24 });
            L.showToast('获得手枪！按 X 射击', 120);
            sfx.save();
          }
          break;
        case 'apple':
          if (!e.taken) { e.taken = true; this.apples++; sfx.save(); }
          break;
        case 'jumpref':
          if (this.animT % 4 === 0) this.jumps = 0;
          break;
        case 'warp': {
          if (e.cool > 0) break;
          e.cool = 40;
          const to = e.to;
          // 自制多面地图的跨面传送门：to = {face, door} —— 交给 main 切换面
          if (to && typeof to === 'object' && !('x' in to) && !('y' in to) && typeof to.face === 'number') {
            if (this.onPortal) this.onPortal(e);
            break;
          }
          // 原有逻辑（同关内传送 / 回出生点 / 绝对坐标 / pair 配对）
          const tgt = to === 'spawn' ? L.spawn
            : to && ('x' in to) ? { x: to.x * TILE, y: to.y * TILE }
              : (() => {
                const p = L.entities.find(o => o.type === 'warp' && o.idx === e.pair);
                return p ? { x: p.x + p.w / 2 - this.w / 2, y: p.y + p.h - this.h } : null;
              })();
          if (tgt) {
            this.x = tgt.x; this.y = tgt.y;
            this.vx = 0; this.vy = 0;
            const partner = L.entities.find(o => o.type === 'warp' && o.idx === e.pair);
            if (partner) partner.cool = 40;
            sfx.warp();
            L.particles.spawn(this.cx, this.cy, 12, { colors: ['#a86bff', '#fff'], speed: 2.5, life: 24 });
          }
          break;
        }
        case 'sign':
          if (this.animT % 30 === 0) L.showToast(e.text, 90);
          break;
      }
    }
  }

  draw(ctx) {
    S.drawKid(ctx, this, this.animT);
  }
}