import freezeObject from '../Core/freezeObject.js';
import WebGLConstants from '../Core/WebGLConstants.js';

    /**
     * @private
     */
    var PixelDatatype = {
        UNSIGNED_BYTE : WebGLConstants.UNSIGNED_BYTE,
        UNSIGNED_SHORT : WebGLConstants.UNSIGNED_SHORT,
        UNSIGNED_INT : WebGLConstants.UNSIGNED_INT,
        FLOAT : WebGLConstants.FLOAT,
        HALF_FLOAT : WebGLConstants.HALF_FLOAT_OES,
        UNSIGNED_INT_24_8 : WebGLConstants.UNSIGNED_INT_24_8,
        UNSIGNED_SHORT_4_4_4_4 : WebGLConstants.UNSIGNED_SHORT_4_4_4_4,
        UNSIGNED_SHORT_5_5_5_1 : WebGLConstants.UNSIGNED_SHORT_5_5_5_1,
        UNSIGNED_SHORT_5_6_5 : WebGLConstants.UNSIGNED_SHORT_5_6_5,

        isPacked : function(pixelDatatype) {
            return pixelDatatype === PixelDatatype.UNSIGNED_INT_24_8 ||
                   pixelDatatype === PixelDatatype.UNSIGNED_SHORT_4_4_4_4 ||
                   pixelDatatype === PixelDatatype.UNSIGNED_SHORT_5_5_5_1 ||
                   pixelDatatype === PixelDatatype.UNSIGNED_SHORT_5_6_5;
        },

        sizeInBytes : function(pixelDatatype) {
            switch (pixelDatatype) {
                case PixelDatatype.UNSIGNED_BYTE:
                    return 1;
                case PixelDatatype.UNSIGNED_SHORT:
                case PixelDatatype.UNSIGNED_SHORT_4_4_4_4:
                case PixelDatatype.UNSIGNED_SHORT_5_5_5_1:
                case PixelDatatype.UNSIGNED_SHORT_5_6_5:
                case PixelDatatype.HALF_FLOAT:
                    return 2;
                case PixelDatatype.UNSIGNED_INT:
                case PixelDatatype.FLOAT:
                case PixelDatatype.UNSIGNED_INT_24_8:
                    return 4;
            }
        },

        validate : function(pixelDatatype) {
            return ((pixelDatatype === PixelDatatype.UNSIGNED_BYTE) ||
                    (pixelDatatype === PixelDatatype.UNSIGNED_SHORT) ||
                    (pixelDatatype === PixelDatatype.UNSIGNED_INT) ||
                    (pixelDatatype === PixelDatatype.FLOAT) ||
                    (pixelDatatype === PixelDatatype.HALF_FLOAT) ||
                    (pixelDatatype === PixelDatatype.UNSIGNED_INT_24_8) ||
                    (pixelDatatype === PixelDatatype.UNSIGNED_SHORT_4_4_4_4) ||
                    (pixelDatatype === PixelDatatype.UNSIGNED_SHORT_5_5_5_1) ||
                    (pixelDatatype === PixelDatatype.UNSIGNED_SHORT_5_6_5));
        }
    };
export default freezeObject(PixelDatatype);