// widget_slider.ysl2

template "widget[@type='Slider']", mode="widget_class"
    ||
    class SliderWidget extends Widget{
        frequency = 5;
        range = undefined;
        fi = undefined;
        svg_dist = undefined;
        drag = false;
        enTimer = false;

        dispatch(value) {
            if(this.value_elt)
                this.value_elt.textContent = String(value);

            this.update_DOM(value, this.handle_elt);

        }

        last_drag = false;

        update_DOM(value, elt){
            let [min,max,start,totallength] = this.range;
            let length = Math.max(0,Math.min(totallength,(Number(value)-min)*totallength/(max-min)));
            let tip = this.range_elt.getPointAtLength(length);
            elt.setAttribute('transform',"translate("+(tip.x-start.x)+","+(tip.y-start.y)+")");

            if(this.setpoint_elt != undefined){
                if(this.last_drag!= this.drag){
                    if(this.drag){
                        this.setpoint_elt.setAttribute("style", this.setpoint_style);
                    }else{
                        this.setpoint_elt.setAttribute("style", "display:none");
                    }
                    this.last_drag = this.drag;
                }
            }
        }

        on_release(evt) {
            window.removeEventListener("touchmove", this.on_bound_drag, true);
            window.removeEventListener("mousemove", this.on_bound_drag, true);

            window.removeEventListener("mouseup", this.bound_on_release, true)
            window.removeEventListener("touchend", this.bound_on_release, true);
            window.removeEventListener("touchcancel", this.bound_on_release, true);
            if(this.drag){
                this.drag = false;
            }
            this.update_position(evt);
        }


        on_drag(evt){
            if(this.enTimer && this.drag){
                this.update_position(evt);
                //reset timer
                this.enTimer = false;
                setTimeout("{hmi_widgets['"+this.element_id+"'].enTimer = true;}", 100);
            }
        }

        update_position(evt){
            var html_dist = 0;

            //calculate size of widget in html
            var range_borders = this.range_elt.getBoundingClientRect();
            var range_length = Math.sqrt( range_borders.height*range_borders.height + range_borders.width*range_borders.width );
            var [minX,minY,maxX,maxY] = [range_borders.left,range_borders.bottom,range_borders.right,range_borders.top];

            //get range and mouse coordinates
            var mouseX = undefined;
            var mouseY = undefined;
            if (evt.type.startsWith("touch")){
                mouseX = Math.ceil(evt.touches[0].clientX);
                mouseY = Math.ceil(evt.touches[0].clientY);
            }
            else{
                mouseX = evt.pageX;
                mouseY = evt.pageY;
            }

            //get handle distance from mouse position
            if (minX > mouseX && minY < mouseY){
                html_dist = 0;
            }
            else if (maxX < mouseX && maxY > mouseY){
                html_dist = range_length;
            }
            else{
                // calculate distace
                if(this.fi > 0.7){
                    html_dist = (minY - mouseY)/Math.sin(this.fi);
                }
                else{
                    html_dist = (mouseX - minX)/Math.cos(this.fi);
                }

                //check if in range
                if (html_dist > range_length){
                    html_dist = range_length;
                }
                else if (html_dist < 0){
                    html_dist = 0;
                }

            }

            this.svg_dist=Math.ceil((html_dist/range_length)*this.range[1]);

            this.apply_hmi_value(0, this.svg_dist);

            // update ghost cursor
            if(this.setpoint_elt != undefined){
                this.request_animate();
            }
        }

        animate(){
            this.update_DOM(this.svg_dist, this.setpoint_elt);
        }

        on_select(evt){
            this.drag = true;
            this.enTimer = true;
            window.addEventListener("touchmove", this.on_bound_drag, true);
            window.addEventListener("mousemove", this.on_bound_drag, true);

            window.addEventListener("mouseup", this.bound_on_release, true)
            window.addEventListener("touchend", this.bound_on_release, true);
            window.addEventListener("touchcancel", this.bound_on_release, true);
            this.update_position(evt);
        }

        init() {
            let min = this.min_elt ?
                        Number(this.min_elt.textContent) :
                        this.args.length >= 1 ? this.args[0] : 0;
            let max = this.max_elt ?
                        Number(this.max_elt.textContent) :
                        this.args.length >= 2 ? this.args[1] : 100;

            this.range = [min, max, this.range_elt.getPointAtLength(0),this.range_elt.getTotalLength()];
            let start = this.range_elt.getPointAtLength(0);
            let end = this.range_elt.getPointAtLength(this.range_elt.getTotalLength());
            this.fi = Math.atan2(start.y-end.y, end.x-start.x);

            this.bound_on_select = this.on_select.bind(this);
            this.bound_on_release = this.on_release.bind(this);
            this.on_bound_drag = this.on_drag.bind(this);

            this.element.addEventListener("mousedown", this.bound_on_select);
            this.element.addEventListener("touchstart", this.bound_on_select);

            if(this.setpoint_elt != undefined){
                this.setpoint_style = this.setpoint_elt.getAttribute("style");
                this.setpoint_elt.setAttribute("style", "display:none");
            }

        }
    }
    ||

template "widget[@type='Slider']", mode="widget_defs" {
    param "hmi_element";
    labels("handle range");
    optional_labels("value min max setpoint");
    |,
}