import { randomRange, SpatialGrid, TAU, distance } from "./utils.js";

const RESOURCE_FOOD = 0;
const RESOURCE_ENERGY = 1;

let nextResourceId = 1;

class Resource {
  constructor(x, y, type, amount) {
    this.id = nextResourceId++;
    this.x = x;
    this.y = y;
    this.type = type;
    this.amount = amount;
    this.maxAmount = amount;
    this.regenRate = type === RESOURCE_FOOD ? 0.3 : 0.15;
    this.pulsePhase = Math.random() * TAU;
    this.alive = true;
  }

  update(dt, regenMultiplier) {
    if (this.amount < this.maxAmount) {
      this.amount = Math.min(
        this.maxAmount,
        this.amount + this.regenRate * regenMultiplier * dt,
      );
    }
    this.pulsePhase += dt * 2;
  }

  consume(amount) {
    const taken = Math.min(this.amount, amount);
    this.amount -= taken;
    if (this.amount <= 0.01) {
      this.alive = false;
    }
    return taken;
  }
}

class WorldEvent {
  constructor(type, x, y, radius, duration, intensity) {
    this.type = type;
    this.x = x;
    this.y = y;
    this.radius = radius;
    this.duration = duration;
    this.elapsed = 0;
    this.intensity = intensity;
    this.active = true;
  }

  update(dt) {
    this.elapsed += dt;
    if (this.elapsed >= this.duration) {
      this.active = false;
    }
  }

  get progress() {
    return this.elapsed / this.duration;
  }

  get currentIntensity() {
    const t = this.progress;
    if (t < 0.1) return this.intensity * (t / 0.1);
    if (t > 0.8) return this.intensity * ((1 - t) / 0.2);
    return this.intensity;
  }
}

export const EVENT_TYPES = {
  bloom: { name: "Resource Bloom", color: "#00ffaa", icon: "B" },
  drought: { name: "Drought", color: "#ff8844", icon: "D" },
  storm: { name: "Energy Storm", color: "#ffee44", icon: "S" },
  catastrophe: { name: "Catastrophe", color: "#ff3366", icon: "!" },
  abundance: { name: "Abundance", color: "#00ff88", icon: "A" },
};

export class World {
  constructor(width, height) {
    this.width = width;
    this.height = height;
    this.resources = [];
    this.events = [];
    this.resourceGrid = new SpatialGrid(width, height, 80);
    this.eventTimer = 0;
    this.eventInterval = randomRange(15, 25);
    this.totalTime = 0;
    this.regenMultiplier = 1.0;

    this.memory = {
      totalBlooms: 0,
      totalDroughts: 0,
      totalCatastrophes: 0,
      recentEvents: [],
    };

    this._initResources();
  }

  _initResources() {
    const foodCount = Math.floor((this.width * this.height) / 8000);
    for (let i = 0; i < foodCount; i++) {
      this.resources.push(
        new Resource(
          randomRange(20, this.width - 20),
          randomRange(20, this.height - 20),
          RESOURCE_FOOD,
          randomRange(15, 40),
        ),
      );
    }

    const energyCount = Math.floor(foodCount * 0.3);
    for (let i = 0; i < energyCount; i++) {
      this.resources.push(
        new Resource(
          randomRange(20, this.width - 20),
          randomRange(20, this.height - 20),
          RESOURCE_ENERGY,
          randomRange(25, 60),
        ),
      );
    }
  }

  update(dt) {
    this.totalTime += dt;

    for (let i = this.resources.length - 1; i >= 0; i--) {
      const r = this.resources[i];
      r.update(dt, this.regenMultiplier);
      if (!r.alive) {
        this.resources.splice(i, 1);
      }
    }

    const targetFood = Math.floor((this.width * this.height) / 8000);
    if (this.resources.length < targetFood * 0.6) {
      const count = Math.min(3, targetFood - this.resources.length);
      for (let i = 0; i < count; i++) {
        this.resources.push(
          new Resource(
            randomRange(20, this.width - 20),
            randomRange(20, this.height - 20),
            Math.random() < 0.75 ? RESOURCE_FOOD : RESOURCE_ENERGY,
            randomRange(15, 40),
          ),
        );
      }
    }

    this.resourceGrid.clear();
    for (const r of this.resources) {
      this.resourceGrid.insert(r, r.x, r.y);
    }

    for (let i = this.events.length - 1; i >= 0; i--) {
      this.events[i].update(dt);
      if (!this.events[i].active) {
        this.events.splice(i, 1);
      }
    }

    this.eventTimer += dt;
    if (this.eventTimer >= this.eventInterval) {
      this.eventTimer = 0;
      this.eventInterval = randomRange(12, 22);
      this._triggerRandomEvent();
    }

    this._updateMemoryEffects();
  }

  _triggerRandomEvent() {
    const types = Object.keys(EVENT_TYPES);
    const weights = [1, 1, 1, 0.3, 1];
    if (this.memory.totalDroughts > this.memory.totalBlooms) {
      weights[0] += 1;
    }
    if (this.memory.totalCatastrophes > 2) {
      weights[3] *= 0.3;
      weights[4] += 1;
    }

    const totalWeight = weights.reduce((a, b) => a + b, 0);
    let r = Math.random() * totalWeight;
    let typeIdx = 0;
    for (let i = 0; i < weights.length; i++) {
      r -= weights[i];
      if (r <= 0) {
        typeIdx = i;
        break;
      }
    }

    const type = types[typeIdx];
    const x = randomRange(100, this.width - 100);
    const y = randomRange(100, this.height - 100);
    const radius = randomRange(120, 250);
    const duration = randomRange(8, 18);

    const event = new WorldEvent(type, x, y, radius, duration, 1.0);
    this.events.push(event);
    this._applyEventEffects(event);

    this.memory.recentEvents.push({ type, time: this.totalTime });
    if (this.memory.recentEvents.length > 20) this.memory.recentEvents.shift();

    if (type === "bloom" || type === "abundance") this.memory.totalBlooms++;
    if (type === "drought") this.memory.totalDroughts++;
    if (type === "catastrophe") this.memory.totalCatastrophes++;

    return event;
  }

  _applyEventEffects(event) {
    switch (event.type) {
      case "bloom": {
        for (let i = 0; i < 8; i++) {
          const angle = Math.random() * TAU;
          const dist = Math.random() * event.radius;
          const rx = event.x + Math.cos(angle) * dist;
          const ry = event.y + Math.sin(angle) * dist;
          if (
            rx > 10 &&
            rx < this.width - 10 &&
            ry > 10 &&
            ry < this.height - 10
          ) {
            this.resources.push(
              new Resource(rx, ry, RESOURCE_FOOD, randomRange(20, 50)),
            );
          }
        }
        break;
      }
      case "drought": {
        for (const r of this.resources) {
          if (distance(r.x, r.y, event.x, event.y) < event.radius) {
            r.amount *= 0.5;
          }
        }
        break;
      }
      case "storm": {
        for (let i = 0; i < 5; i++) {
          const angle = Math.random() * TAU;
          const dist = Math.random() * event.radius;
          const rx = event.x + Math.cos(angle) * dist;
          const ry = event.y + Math.sin(angle) * dist;
          if (
            rx > 10 &&
            rx < this.width - 10 &&
            ry > 10 &&
            ry < this.height - 10
          ) {
            this.resources.push(
              new Resource(rx, ry, RESOURCE_ENERGY, randomRange(30, 70)),
            );
          }
        }
        break;
      }
      case "abundance": {
        this.regenMultiplier = 2.0;
        setTimeout(() => {
          this.regenMultiplier = 1.0;
        }, event.duration * 1000);
        break;
      }
    }
  }

  _updateMemoryEffects() {
    if (this.memory.totalCatastrophes > 3) {
      this.regenMultiplier = Math.max(this.regenMultiplier, 1.2);
    }
  }

  getResourcesNear(x, y, radius) {
    return this.resourceGrid.query(x, y, radius);
  }

  getEventsAt(x, y) {
    const affecting = [];
    for (const e of this.events) {
      if (distance(x, y, e.x, e.y) < e.radius) {
        affecting.push(e);
      }
    }
    return affecting;
  }

  getCatastropheDamage(x, y) {
    let dmg = 0;
    for (const e of this.events) {
      if (e.type === "catastrophe") {
        const d = distance(x, y, e.x, e.y);
        if (d < e.radius) {
          dmg += e.currentIntensity * (1 - d / e.radius) * 0.5;
        }
      }
    }
    return dmg;
  }

  render(ctx) {
    if (
      !this._bgCache ||
      this._bgCache.width !== this.width ||
      this._bgCache.height !== this.height
    ) {
      this._bgCache = document.createElement("canvas");
      this._bgCache.width = this.width;
      this._bgCache.height = this.height;
      const bgCtx = this._bgCache.getContext("2d");
      const spacing = 35;
      bgCtx.fillStyle = "rgba(80, 160, 220, 0.025)";
      for (let x = spacing; x < this.width; x += spacing) {
        for (let y = spacing; y < this.height; y += spacing) {
          bgCtx.fillRect(x, y, 1.2, 1.2);
        }
      }
      bgCtx.strokeStyle = "rgba(60, 120, 180, 0.015)";
      bgCtx.lineWidth = 0.5;
      for (let x = spacing; x < this.width; x += spacing * 4) {
        bgCtx.beginPath();
        bgCtx.moveTo(x, 0);
        bgCtx.lineTo(x, this.height);
        bgCtx.stroke();
      }
      for (let y = spacing; y < this.height; y += spacing * 4) {
        bgCtx.beginPath();
        bgCtx.moveTo(0, y);
        bgCtx.lineTo(this.width, y);
        bgCtx.stroke();
      }
    }
    ctx.drawImage(this._bgCache, 0, 0);

    for (const e of this.events) {
      const info = EVENT_TYPES[e.type];
      const intensity = e.currentIntensity;
      const rgb = this._hexToRgb(info.color);

      const grad = ctx.createRadialGradient(e.x, e.y, 0, e.x, e.y, e.radius);
      grad.addColorStop(
        0,
        `rgba(${rgb.r},${rgb.g},${rgb.b},${0.08 * intensity})`,
      );
      grad.addColorStop(
        0.7,
        `rgba(${rgb.r},${rgb.g},${rgb.b},${0.03 * intensity})`,
      );
      grad.addColorStop(1, `rgba(${rgb.r},${rgb.g},${rgb.b},0)`);
      ctx.fillStyle = grad;
      ctx.beginPath();
      ctx.arc(e.x, e.y, e.radius, 0, TAU);
      ctx.fill();

      const ringPulse = 0.5 + 0.5 * Math.sin(this.totalTime * 2);
      ctx.strokeStyle = `rgba(${rgb.r},${rgb.g},${rgb.b},${0.15 * intensity * ringPulse})`;
      ctx.lineWidth = 1.5;
      ctx.setLineDash([8, 8]);
      ctx.stroke();
      ctx.setLineDash([]);

      ctx.fillStyle = `rgba(${rgb.r},${rgb.g},${rgb.b},${0.3 * intensity})`;
      ctx.font = "10px Courier New";
      ctx.textAlign = "center";
      ctx.fillText(info.name.toUpperCase(), e.x, e.y - e.radius + 15);
      ctx.textAlign = "start";
    }

    if (!this._foodGlow) {
      this._foodGlow = this._makeGlowSprite(0, 255, 170, 20);
      this._energyGlow = this._makeGlowSprite(255, 238, 68, 20);
    }

    for (const r of this.resources) {
      const pulse = 0.6 + 0.4 * Math.sin(r.pulsePhase);
      const sizeRatio = r.amount / r.maxAmount;
      const baseRadius = 3 + sizeRatio * 4;
      const radius = baseRadius * (0.85 + 0.15 * pulse);

      const sprite =
        r.type === RESOURCE_FOOD ? this._foodGlow : this._energyGlow;
      const gs = sprite.width;
      ctx.globalAlpha = 0.4 + 0.4 * sizeRatio;
      ctx.drawImage(sprite, r.x - gs / 2, r.y - gs / 2);
      ctx.globalAlpha = 1;

      if (r.type === RESOURCE_FOOD) {
        ctx.fillStyle = `rgba(0,255,170,${0.5 + 0.4 * sizeRatio})`;
      } else {
        ctx.fillStyle = `rgba(255,238,68,${0.5 + 0.4 * sizeRatio})`;
      }
      ctx.beginPath();
      ctx.arc(r.x, r.y, radius, 0, TAU);
      ctx.fill();
    }
  }

  _makeGlowSprite(r, g, b, size) {
    const canvas = document.createElement("canvas");
    const s = size * 3;
    canvas.width = s;
    canvas.height = s;
    const ctx = canvas.getContext("2d");
    const grad = ctx.createRadialGradient(s / 2, s / 2, 0, s / 2, s / 2, s / 2);
    grad.addColorStop(0, `rgba(${r},${g},${b},0.3)`);
    grad.addColorStop(0.5, `rgba(${r},${g},${b},0.08)`);
    grad.addColorStop(1, `rgba(${r},${g},${b},0)`);
    ctx.fillStyle = grad;
    ctx.fillRect(0, 0, s, s);
    return canvas;
  }

  _hexToRgb(hex) {
    const r = parseInt(hex.slice(1, 3), 16);
    const g = parseInt(hex.slice(3, 5), 16);
    const b = parseInt(hex.slice(5, 7), 16);
    return { r, g, b };
  }

  toJSON() {
    return {
      width: this.width,
      height: this.height,
      totalTime: this.totalTime,
      memory: { ...this.memory },
      resources: this.resources.map((r) => ({
        x: r.x,
        y: r.y,
        type: r.type,
        amount: r.amount,
        maxAmount: r.maxAmount,
      })),
    };
  }

  static fromJSON(data) {
    const w = new World(data.width, data.height);
    w.resources = [];
    w.totalTime = data.totalTime || 0;
    w.memory = data.memory || w.memory;
    for (const rd of data.resources) {
      const r = new Resource(rd.x, rd.y, rd.type, rd.maxAmount);
      r.amount = rd.amount;
      w.resources.push(r);
    }
    return w;
  }
}