import * as THREE from "three";
import { SceneSetup } from "./scene/SceneSetup.js";
import { PathBuilder } from "./scene/PathBuilder.js";
import { GameState } from "./game/GameState.js";
import { UIManager } from "./ui/UIManager.js";
import { Enemy } from "./entities/Enemy.js";
import { Tower } from "./entities/Tower.js";
import {
  TOWER_TYPES,
  PATH_POINTS,
  PROJECTILE_SPEED,
  GRID_CELL_SIZE,
} from "./config/gameConfig.js";
import {
  snapToGrid,
  isOnRoad,
  EffectSystem,
  worldToCell,
  cellToWorldCenter,
} from "./utils/utils.js";

// Initialize game components
const sceneSetup = new SceneSetup();
const pathBuilder = new PathBuilder(sceneSetup.scene);
const gameState = new GameState();
const uiManager = new UIManager();
const effectSystem = new EffectSystem(sceneSetup.scene);

// Make UIManager globally accessible for tower sound system
window.UIManager = uiManager;

// Build the path
pathBuilder.buildPath();

// Initialize UI
uiManager.setWavesTotal(gameState.totalWaves);
uiManager.updateHUD(gameState);
uiManager.setMessage(
  "Click on the ground to place a tower. Press G to toggle grid."
);

// Initialize speed control UI
if (typeof uiManager.initSpeedControls === "function") {
  uiManager.initSpeedControls(gameState.getGameSpeed());
}
if (typeof uiManager.onSpeedChange === "function") {
  uiManager.onSpeedChange((speed) => {
    if (typeof gameState.setGameSpeed === "function") {
      gameState.setGameSpeed(speed);
    } else {
      gameState.gameSpeed = speed === 2 ? 2 : 1;
    }
    if (typeof uiManager.updateSpeedControls === "function") {
      uiManager.updateSpeedControls(
        gameState.getGameSpeed ? gameState.getGameSpeed() : gameState.gameSpeed
      );
    }
  });
}

/**
 * Raycaster and pointer state
 */
const raycaster = new THREE.Raycaster();
const mouse = new THREE.Vector2();
// Track hovered tower for outline toggle
let hoveredTower = null;

// Drag/rotation suppression to avoid triggering click after a drag
let isPointerDown = false;
let didDrag = false;
let downPos = { x: 0, y: 0 };
// pixels moved to consider it a drag (tuned to ignore minor jitter)
const DRAG_SUPPRESS_PX = 8;

// Hover highlight overlay (cell preview)
const hoverMaterial = new THREE.MeshBasicMaterial({
  color: 0x3a97ff,
  transparent: true,
  opacity: 0.25,
  depthWrite: false,
});
const hoverGeo = new THREE.PlaneGeometry(GRID_CELL_SIZE, GRID_CELL_SIZE);
const hoverMesh = new THREE.Mesh(hoverGeo, hoverMaterial);
hoverMesh.rotation.x = -Math.PI / 2;
hoverMesh.visible = false;
sceneSetup.scene.add(hoverMesh);

// Track last hovered center to reuse on click
let lastHoveredCenter = null;

function updateHover(e) {
  // Track drag distance while pointer is down to suppress click-after-drag
  if (isPointerDown) {
    const dx = e.clientX - downPos.x;
    const dy = e.clientY - downPos.y;
    if (!didDrag && dx * dx + dy * dy >= DRAG_SUPPRESS_PX * DRAG_SUPPRESS_PX) {
      didDrag = true;
    }
  }
  if (!gameState.isGameActive()) {
    hoverMesh.visible = false;
    // clear tower hover when game inactive
    if (hoveredTower) {
      hoveredTower.setHovered(false);
      hoveredTower = null;
    }
    return;
  }
  mouse.x = (e.clientX / window.innerWidth) * 2 - 1;
  mouse.y = -(e.clientY / window.innerHeight) * 2 + 1;
  raycaster.setFromCamera(mouse, sceneSetup.camera);

  // 1) Tower hover detection via raycast
  const towerMeshes = gameState.towers.map((t) => t.mesh);
  const tHits = towerMeshes.length
    ? raycaster.intersectObjects(towerMeshes, true)
    : [];
  if (tHits.length > 0) {
    const hitObj = tHits[0].object;
    const owner = gameState.towers.find(
      (t) =>
        hitObj === t.mesh ||
        t.mesh.children.includes(hitObj) ||
        t.head === hitObj ||
        t.ring === hitObj ||
        t.mesh.children.some((c) => c === hitObj)
    );
    if (owner) {
      if (hoveredTower && hoveredTower !== owner) {
        hoveredTower.setHovered(false);
      }
      hoveredTower = owner;
      hoveredTower.setHovered(true);
    }
  } else {
    if (hoveredTower) {
      hoveredTower.setHovered(false);
      hoveredTower = null;
    }
  }

  // 2) Ground hover preview (existing behavior)
  const intersects = raycaster.intersectObjects([sceneSetup.ground], false);
  if (intersects.length === 0) {
    hoverMesh.visible = false;
    lastHoveredCenter = null;
    return;
  }

  const p = intersects[0].point.clone();
  p.y = 0;

  // Convert to cell center
  const { col, row } = worldToCell(p.x, p.z, GRID_CELL_SIZE);
  const center = cellToWorldCenter(col, row, GRID_CELL_SIZE);

  // Determine validity using existing constraints
  const valid = canPlaceTowerAt(center);

  hoverMesh.position.set(center.x, 0.01, center.z);
  hoverMesh.material.color.setHex(valid ? 0x3a97ff : 0xff5555);
  hoverMesh.visible = true;

  lastHoveredCenter = center;
}

function canPlaceTowerAt(pos) {
  if (isOnRoad(pos)) {
    uiManager.setMessage("Can't place on the road!");
    return false;
  }
  // Allow edge-adjacent placement: threshold based on grid size
  const minSeparation = 0.9 * GRID_CELL_SIZE;
  for (const t of gameState.towers) {
    if (t.position.distanceTo(pos) < minSeparation) {
      uiManager.setMessage("Too close to another tower.");
      return false;
    }
  }
  return true;
}

// Game functions
function resetGame() {
  // Clean up entities
  gameState.enemies.forEach((e) => e.destroy());
  gameState.towers.forEach((t) => t.destroy());
  gameState.projectiles.forEach((p) => p.destroy());

  // Reset game state
  gameState.reset();

  // Ensure speed is reset to x1 at the start of a new game
  if (typeof gameState.setGameSpeed === "function") {
    gameState.setGameSpeed(1);
  } else {
    gameState.gameSpeed = 1;
  }
  if (typeof uiManager.updateSpeedControls === "function") {
    uiManager.updateSpeedControls(
      gameState.getGameSpeed ? gameState.getGameSpeed() : gameState.gameSpeed
    );
  }

  // Update UI
  uiManager.setMessage(
    "Click on the ground to place a tower. Press G to toggle grid."
  );
  uiManager.updateHUD(gameState);
}

function spawnEnemy(wave) {
  const enemy = new Enemy(
    wave.hp,
    wave.speed,
    wave.reward,
    PATH_POINTS,
    sceneSetup.scene
  );
  gameState.addEnemy(enemy);
}

function setSelectedTower(tower) {
  // Clear old selection
  if (gameState.selectedTower) {
    gameState.selectedTower.setSelected(false);
  }

  gameState.setSelectedTower(tower);

  if (tower) {
    tower.setSelected(true);
    uiManager.showUpgradePanel(tower, gameState.money);
  } else {
    uiManager.hideUpgradePanel();
  }
}

// Event handlers
function onClick(e) {
  if (!gameState.isGameActive()) return;

  // Ignore clicks on UI elements
  if (e.target.tagName !== 'CANVAS') {
    return;
  }

  // If a drag/rotate/pan occurred, suppress the click action entirely
  if (didDrag) {
    didDrag = false; // reset for next interaction
    // Also clear any transient hover
    if (hoveredTower) {
      hoveredTower.setHovered(false);
      hoveredTower = null;
    }
    return;
  }

  mouse.x = (e.clientX / window.innerWidth) * 2 - 1;
  mouse.y = -(e.clientY / window.innerHeight) * 2 + 1;
  raycaster.setFromCamera(mouse, sceneSetup.camera);

  // First, try to select a tower
  const towerMeshes = gameState.towers.map((t) => t.mesh);
  const tHits = raycaster.intersectObjects(towerMeshes, true);

  if (tHits.length > 0) {
    // Find owning tower
    const hit = tHits[0].object;
    const owner = gameState.towers.find(
      (t) =>
        hit === t.mesh ||
        t.mesh.children.includes(hit) ||
        t.head === hit ||
        t.ring === hit ||
        t.mesh.children.some((c) => c === hit)
    );
    if (owner) {
      setSelectedTower(owner);
      return;
    }
  }

  // Otherwise, handle ground placement and deselection
  const intersects = raycaster.intersectObjects([sceneSetup.ground], false);
  if (intersects.length > 0) {
    const p = intersects[0].point.clone();
    p.y = 0;

    // Deselect if clicking ground without Shift
    if (!e.shiftKey) {
      setSelectedTower(null);
    }

    // Compute exact cell center instead of intersection
    const { col, row } = worldToCell(p.x, p.z, GRID_CELL_SIZE);
    const pCenter = cellToWorldCenter(col, row, GRID_CELL_SIZE);

    // Place constraints based on center
    if (!canPlaceTowerAt(pCenter)) {
      return;
    }

    // Build palette options based on affordability
    const opts = [
      {
        key: "basic",
        name: TOWER_TYPES.basic.name,
        cost: TOWER_TYPES.basic.cost,
        enabled: gameState.canAfford(TOWER_TYPES.basic.cost),
        desc: "Balanced tower",
        color: "#3a97ff",
      },
      {
        key: "slow",
        name: TOWER_TYPES.slow.name,
        cost: TOWER_TYPES.slow.cost,
        enabled: gameState.canAfford(TOWER_TYPES.slow.cost),
        desc: "On-hit slow for 2.5s",
        color: "#2fa8ff",
      },
      {
        key: "sniper",
        name: TOWER_TYPES.sniper.name,
        cost: TOWER_TYPES.sniper.cost,
        enabled: gameState.canAfford(TOWER_TYPES.sniper.cost),
        desc: "Long range, slow fire, high damage; aims before firing",
        color: "#ff3b30",
      },
      // New Electric tower option
      ...(TOWER_TYPES.electric
        ? [
            {
              key: "electric",
              name: TOWER_TYPES.electric.name,
              cost: TOWER_TYPES.electric.cost,
              enabled: gameState.canAfford(TOWER_TYPES.electric.cost),
              desc: "Electric arcs hit up to 3 enemies",
              color: "#9ad6ff",
            },
          ]
        : []),
    ];

    // Show palette near click
    uiManager.showTowerPalette(e.clientX, e.clientY, opts);

    // One-time handlers
    const handleSelect = (key) => {
      const def = TOWER_TYPES[key];
      if (!def) return;
      // Re-validate position and funds at selection time
      if (!canPlaceTowerAt(pCenter)) return;
      if (!gameState.canAfford(def.cost)) {
        uiManager.setMessage("Not enough money!");
        return;
      }
      gameState.spendMoney(def.cost);
      uiManager.updateHUD(gameState);
      const tower = new Tower(pCenter, def, sceneSetup.scene);
      gameState.addTower(tower);
      uiManager.setMessage(`${def.name} placed!`);
    };
    const handleCancel = () => {
      // No-op, message can be preserved
    };

    uiManager.onPaletteSelect((key) => handleSelect(key));
    uiManager.onPaletteCancel(() => handleCancel());
  } else {
    setSelectedTower(null);
  }
  // clear any hover state after processing click (prevents stuck outline)
  if (hoveredTower) {
    hoveredTower.setHovered(false);
    hoveredTower = null;
  }
}

/**
 * Pointer handlers to detect drags (used to suppress click after rotate/pan)
 */
function onMouseDown(e) {
  // Only consider primary or secondary buttons; ignore other cases
  isPointerDown = true;
  didDrag = false;
  downPos.x = e.clientX;
  downPos.y = e.clientY;
}

function onMouseUp() {
  // End drag tracking; let click handler run, which will check didDrag
  isPointerDown = false;
}

// Setup event listeners
window.addEventListener("click", onClick);
window.addEventListener("mousemove", updateHover);
window.addEventListener("mousedown", onMouseDown);
window.addEventListener("mouseup", onMouseUp);

// Arrow key state tracking for smooth camera movement
const keyState = {
  ArrowUp: false,
  ArrowDown: false,
  ArrowLeft: false,
  ArrowRight: false,
};

window.addEventListener("keydown", (e) => {
  if (e.key === "Escape") {
    setSelectedTower(null);
  }
  if (e.key === "g" || e.key === "G") {
    sceneSetup.grid.visible = !sceneSetup.grid.visible;
    uiManager.setMessage(sceneSetup.grid.visible ? "Grid on" : "Grid off");
  }
  if (e.key in keyState) {
    keyState[e.key] = true;
  }
});

window.addEventListener("keyup", (e) => {
  if (e.key in keyState) {
    keyState[e.key] = false;
  }
});

uiManager.onRestartClick(() => resetGame());

uiManager.onUpgradeClick(() => {
  const tower = gameState.selectedTower;
  if (!tower) return;

  if (!tower.canUpgrade) {
    uiManager.setMessage("Tower is at max level.");
    uiManager.showUpgradePanel(tower, gameState.money);
    return;
  }

  if (!gameState.canAfford(tower.nextUpgradeCost)) {
    uiManager.setMessage("Not enough money to upgrade.");
    uiManager.showUpgradePanel(tower, gameState.money);
    return;
  }

  gameState.spendMoney(tower.nextUpgradeCost);
  const ok = tower.upgrade();
  if (ok) {
    uiManager.updateHUD(gameState);
    uiManager.setMessage("Tower upgraded.");
    uiManager.showUpgradePanel(tower, gameState.money);
  }
});

uiManager.onSellClick(() => {
  const tower = gameState.selectedTower;
  if (!tower) return;

  const refund = tower.getSellValue();
  gameState.addMoney(refund);
  uiManager.updateHUD(gameState);

  tower.destroy();
  gameState.removeTower(tower);
  uiManager.setMessage(`Tower sold for ${refund}.`);
  setSelectedTower(null);
});

// Wave spawning
function updateSpawning(dt) {
  if (!gameState.isGameActive()) return;

  const wave = gameState.getCurrentWave();
  if (!wave) return;

  // Accumulate scaled time and spawn at intervals
  if (gameState.spawnedThisWave < wave.count) {
    gameState.spawnAccum += dt;
    while (
      gameState.spawnedThisWave < wave.count &&
      gameState.spawnAccum >= wave.spawnInterval
    ) {
      spawnEnemy(wave);
      gameState.spawnedThisWave++;
      gameState.spawnAccum -= wave.spawnInterval;
    }
  } else {
    // Wait until all enemies are cleared to progress
    if (gameState.enemies.length === 0) {
      gameState.nextWave();
      uiManager.updateHUD(gameState);

      // Infinite waves: always start the next wave
      if (gameState.startWave()) {
        uiManager.setMessage(`Wave ${gameState.waveIndex + 1} started!`);
      }
    }
  }
}

// Main game loop
let lastTime = performance.now() / 1000;

function animate() {
  requestAnimationFrame(animate);

  const now = performance.now() / 1000;
  const dtRaw = Math.min(0.05, now - lastTime);
  lastTime = now;

  // Scaled gameplay dt based on GameState speed
  const speed =
    typeof gameState.getGameSpeed === "function"
      ? gameState.getGameSpeed()
      : gameState.gameSpeed || 1;
  const dt = dtRaw * speed;

  // Camera movement via arrow keys should remain unscaled for consistent navigation
  const moveDir = { x: 0, z: 0 };
  if (keyState.ArrowUp) moveDir.z -= 1;
  if (keyState.ArrowDown) moveDir.z += 1;
  if (keyState.ArrowLeft) moveDir.x -= 1;
  if (keyState.ArrowRight) moveDir.x += 1;
  if (moveDir.x !== 0 || moveDir.z !== 0) {
    sceneSetup.moveCamera(moveDir, dtRaw);
  }

  if (gameState.isGameActive()) {
    // Spawning must use scaled dt to respect speed
    updateSpawning(dt);

    // Update enemies
    for (let i = gameState.enemies.length - 1; i >= 0; i--) {
      const enemy = gameState.enemies[i];
      const status = enemy.update(dt);

      if (enemy.isDead()) {
        gameState.addMoney(enemy.reward);
        uiManager.updateHUD(gameState);
        enemy.destroy();
        gameState.removeEnemy(enemy);
        continue;
      }

      if (status === "end") {
        gameState.takeDamage(1);
        uiManager.updateHUD(gameState);
        enemy.destroy();
        gameState.removeEnemy(enemy);

        if (gameState.gameOver) {
          uiManager.setMessage("Game Over! Enemies broke through.");
        }
      }
    }

    // Update towers
    for (const tower of gameState.towers) {
      tower.tryFire(
        dt,
        gameState.enemies,
        gameState.projectiles,
        PROJECTILE_SPEED
      );
    }

    // Keep upgrade panel in sync if selected
    if (gameState.selectedTower) {
      uiManager.showUpgradePanel(gameState.selectedTower, gameState.money);
    }

    // Update projectiles
    for (let i = gameState.projectiles.length - 1; i >= 0; i--) {
      const projectile = gameState.projectiles[i];
      const status = projectile.update(dt, (pos) =>
        effectSystem.spawnHitEffect(pos)
      );

      if (status !== "ok") {
        projectile.destroy();
        gameState.removeProjectile(projectile);
      }
    }

    effectSystem.update(dt);
  }

  sceneSetup.render();
}

// Start the game
setTimeout(() => {
  if (gameState.startWave()) {
    uiManager.setMessage(`Wave 1 started!`);
  }
}, 1200);

animate();