module Neon.Client {

    export class ShaderHelper {

        private static _instance: ShaderHelper;

        game: Phaser.Game;

        shaderTV: Phaser.Filter;

        constructor(game: Phaser.Game) {
            this.game = game;

            var tvFragment = [
                "#ifdef GL_ES",
                "precision highp float;",
                "#endif",

                "uniform vec2 resolution;",
                "uniform float time;",
                "uniform sampler2D iChannel0;",
                "float rand(vec2 co) {",
                "return fract(sin(dot(co.xy, vec2(12.9898, 78.233))) * 43758.5453);",
                "}",
                "void main(void) ",
                "{",
                "vec2 q = gl_FragCoord.xy / resolution.xy;",
                "vec2 uv = 0.5 + (q - 0.5) * (0.98 + 0.006 * sin(0.9 * time));",
                "vec3 oricol = texture2D(iChannel0, vec2(q.x, 1.0 - q.y)).xyz;",
                "vec3 col;",
                "oricol.r = texture2D(iChannel0, vec2(uv.x + 0.003, uv.y)).x;",
                "oricol.g = texture2D(iChannel0, vec2(uv.x + 0.000, uv.y)).y;",
                "oricol.b = texture2D(iChannel0, vec2(uv.x - 0.003, uv.y)).z;",
                "oricol *= 0.6 + 0.4 * 16.0 * uv.x * uv.y * (1.0 - uv.x) * (1.0 - uv.y);",
                "oricol *= vec3(0.7, 0.8, 0.85);",
                "oricol *= 0.8 + 0.2 * sin(10.0 * time + uv.y * 200.0);",
                "oricol *= 1.0 - 0.07 * rand(vec2(time, tan(time)));",
                "gl_FragColor = vec4(oricol, 0.5);",
                "}"
            ];

            this.shaderTV = new Phaser.Filter(this.game, null, tvFragment);
            this.shaderTV.setResolution(640, 360);

            this.game.stage.filters = [this.shaderTV];

            ShaderHelper._instance = this;
        }

        update() {
            this.shaderTV.update();
        }

        public static init(game: Phaser.Game) {
            if (ShaderHelper._instance == null)
                ShaderHelper._instance = new ShaderHelper(game);
        }

        public static getInstance() {
            return ShaderHelper._instance;
        }

    }

}