const  { Cesium }  = DC.Namespace

function S3MCreateIndexBufferJob(){
    this.model = undefined;
    this.context = undefined;
    this.index = 0;
}

S3MCreateIndexBufferJob.prototype.set = function(context, model, index) {
    this.model = model;
    this.context = context;
    this.index = index;
};

S3MCreateIndexBufferJob.prototype.execute = function(){
    let context = this.context;
    let indexPackage = this.model.arrIndexPackage[this.index];
    let verticesCount = this.model.vertexPackage.verticesCount;
    if(!Cesium.defined(indexPackage)){
        throw new Cesium.DeveloperError('index package is null');
    }

    if(Cesium.defined(indexPackage.indexBuffer)){
        return ;
    }

    if(!Cesium.defined(indexPackage.indicesTypedArray)){
        throw new Cesium.DeveloperError('index buffer is null');
    }

    let indexDataType = Cesium.IndexDatatype.UNSIGNED_SHORT;
    if((indexPackage.indexType === 1 || verticesCount >= Cesium.Math.SIXTY_FOUR_KILOBYTES) && context.elementIndexUint) {
        indexDataType = Cesium.IndexDatatype.UNSIGNED_INT;
    }

    if(!Cesium.defined(indexPackage.indexBuffer)){
        indexPackage.indexBuffer = Cesium.Buffer.createIndexBuffer({
            context : context,
            typedArray : indexPackage.indicesTypedArray,
            usage : Cesium.BufferUsage.STATIC_DRAW,
            indexDatatype : indexDataType
        });
    }

    indexPackage.indicesTypedArray = null;
    delete indexPackage.indicesTypedArray;
};

export default S3MCreateIndexBufferJob;