"use strict";

class HillSet
{
	constructor(inSize, inHeightRange, inColour, inSpeed)
	{
		if(typeof inSize != "object") inSize = new Vector(2048, 1024);
		if(typeof inHeightRange != "number") inHeightRange = 0.4;
		if(typeof inColour != "string") inColour = "green";
		if(typeof inSpeed != "number") inSpeed = 30;
		
		this.pos = new Vector(0, 0);
		this.startPos = this.pos.clone();
		this.size = inSize;
		this.colour = inColour;
		this.speed = inSpeed; // in pixels per second
		
		this.heightRangeMultiplier = inHeightRange;
		this.heightRange = this.heightRangeMultiplier * this.size.y;
		this.controlPointInterval = 128; // Must devide exactly into pos.size.x
		
		this.generate();
	}
	
	generate()
	{
		this.controlPoints = [];
		
		for (let x = 0, i = 0; x <= this.size.x; x += this.controlPointInterval, i++)
		{
			this.controlPoints.push(new Vector(
				x + (i !== 0 ? random(25) : 0),
				random(this.heightRange) + ((random(2) == 0) ? ((this.size.y - this.heightRange) * random(0.5, 1, true)) : 0)
			));
		}
		
		// Make everything as seamless as possible
		
		this.hillLine = new SmoothLine();
		this.hillLine.add(this.controlPoints[this.controlPoints.length - 3].clone().subtract(new Vector(this.size.x * 2, 0)));
		this.hillLine.add(this.controlPoints[this.controlPoints.length - 2].clone().subtract(new Vector(this.size.x * 2, 0)));
		// TODO: Add a few points before this to make th  smooth line join up upon reset correctly
		var prevPoints = [];
		for(let point of this.controlPoints)
			prevPoints.push(point.clone().subtract(new Vector(this.size.x, 0)));
		prevPoints.pop(); // Remove the last point because it's essentially the same as the first regular point
		this.hillLine.add(prevPoints); // The points to the left
		
		this.hillLine.add(this.controlPoints); // Add the regular points
	}
	
	/**
	 * Updates the hillset ready for the next frame.
	 * @param  {number} dt The number of seconds since the last frame.
	 */
	update(dt)
	{
		this.pos.x += this.speed * dt;
		if(this.pos.x >= this.size.x)
			// console.log("Reset");
			this.pos.x = 0;
	}
	
	render(context)
	{
		context.save();
		context.translate(this.pos.x, this.pos.y);
		
		/*context.fillStyle = "red";
		context.beginPath();
		context.ellipse(0, 0, 10, 10, 0, 0, Math.PI * 2, false);
		context.fill();*/
		
		context.beginPath();
		context.moveTo(0, this.size.y);
		context.lineTo(-this.size.x, this.size.y);
		/*for(let point of this.controlPoints)
		{
			context.lineTo(point.x, point.y);
		}*/
		this.hillLine.line(context, 16);
		context.lineTo(this.size.x, this.size.y);
		context.closePath();
		
		context.fillStyle = this.colour;
		context.fill();
		
		
		context.restore();
	}
	
	toString()
	{
		return `HillSet @ ${this.pos} (${this.size}), Control Points x${this.controlPoints.length}: ${this.controlPoints.join(", ")}`;
	}
}