// NPC Entity
// NPC z random walk AI in isometrično podporo
class NPC {
    constructor(scene, gridX, gridY, offsetX = 0, offsetY = 0, type = 'zombie') {
        this.scene = scene;
        this.gridX = gridX;
        this.gridY = gridY;
        this.type = type;

        // Terrain offset
        this.offsetX = offsetX;
        this.offsetY = offsetY;

        this.iso = new IsometricUtils(48, 24);

        // Random walk paramters
        this.moveSpeed = 100; // px/s (počasnejše od igralca)
        this.gridMoveTime = 300; // ms za premik (počasneje)

        // Stanje
        this.isMoving = false;
        this.pauseTime = 0;
        this.maxPauseTime = 2000; // Pavza med premiki (2s)

        // Kreira sprite
        this.createSprite();

        // Začetna pozicija
        this.updatePosition();

        // Naključna začetna pavza
        this.pauseTime = Math.random() * this.maxPauseTime;
    }

    createSprite() {
        // Check for custom sprites first
        let texKey = `npc_${this.type}`;

        if (this.type === 'zombie' && this.scene.textures.exists('zombie_sprite')) {
            texKey = 'zombie_sprite';
        } else if (this.type === 'merchant' && this.scene.textures.exists('merchant_sprite')) {
            texKey = 'merchant_sprite';
        } else if (!this.scene.textures.exists(texKey)) {
            TextureGenerator.createNPCSprite(this.scene, texKey, this.type);
        }

        // Kreira sprite
        const screenPos = this.iso.toScreen(this.gridX, this.gridY);
        this.sprite = this.scene.add.sprite(
            screenPos.x + this.offsetX,
            screenPos.y + this.offsetY,
            texKey
        );
        this.sprite.setOrigin(0.5, 1);
        this.sprite.setScale(0.3); // Optimized for visibility

        // Depth sorting
        this.updateDepth();
    }

    update(delta) {
        if (this.isMoving) {
            return; // Že se premika
        }

        // Random walk - pavza med premiki
        this.pauseTime += delta;

        if (this.pauseTime >= this.maxPauseTime) {
            this.performRandomWalk();
            this.pauseTime = 0;
        }
    }

    performRandomWalk() {
        // Naključna smer (NSEW + možnost obstati)
        const directions = [
            { x: -1, y: 0 },  // North-West
            { x: 1, y: 0 },   // South-East
            { x: 0, y: -1 },  // South-West
            { x: 0, y: 1 },   // North-East
            { x: 0, y: 0 }    // Stay (30% možnost)
        ];

        const dir = Phaser.Math.RND.pick(directions);
        const targetX = this.gridX + dir.x;
        const targetY = this.gridY + dir.y;

        // Preveri kolizijo z robovi
        const terrainSystem = this.scene.terrainSystem;
        if (terrainSystem && this.iso.isInBounds(targetX, targetY, terrainSystem.width, terrainSystem.height)) {
            // Preveri da ni ista pozicija kot igralec
            if (this.scene.player) {
                const playerPos = this.scene.player.getPosition();
                if (targetX === playerPos.x && targetY === playerPos.y) {
                    return; // Ne premakni se na igralca
                }
            }

            if (dir.x !== 0 || dir.y !== 0) {
                this.moveToGrid(targetX, targetY);
            }
        }
    }

    moveToGrid(targetX, targetY) {
        this.isMoving = true;
        this.gridX = targetX;
        this.gridY = targetY;

        const targetScreen = this.iso.toScreen(targetX, targetY);

        // Tween za smooth gibanje
        this.scene.tweens.add({
            targets: this.sprite,
            x: targetScreen.x + this.offsetX,
            y: targetScreen.y + this.offsetY,
            duration: this.gridMoveTime,
            ease: 'Linear',
            onComplete: () => {
                this.isMoving = false;
            }
        });

        // Posodobi depth
        this.updateDepth();
    }

    updatePosition() {
        const screenPos = this.iso.toScreen(this.gridX, this.gridY);
        this.sprite.setPosition(
            screenPos.x + this.offsetX,
            screenPos.y + this.offsetY
        );
        this.updateDepth();
    }

    updateDepth() {
        const depth = this.iso.getDepth(this.gridX, this.gridY);
        this.sprite.setDepth(depth + 1000); // +1000 da je nad terenom
    }

    getPosition() {
        return { x: this.gridX, y: this.gridY };
    }

    destroy() {
        if (this.sprite) {
            this.sprite.destroy();
        }
    }
}