edouard@3241: // widget_foreach.ysl2
edouard@3241: 
edouard@3241: widget_desc("ForEach") {
edouard@3241: 
edouard@3241:     longdesc
edouard@3241:     ||
edouard@3241:     ForEach widget is used to span a small set of widget over a larger set of
edouard@3241:     repeated HMI_NODEs. 
edouard@3241: 
edouard@3241:     Idea is somewhat similar to relative page, but it all happens inside the
edouard@3241:     ForEach widget, no page involved.
edouard@3241: 
edouard@3241:     Together with relative Jump widgets it can be used to build a menu to reach
edouard@3241:     relative pages covering many identical HMI_NODES siblings.
edouard@3241: 
edouard@3241:     ForEach widget takes a HMI_CLASS name as argument and a HMI_NODE path as
edouard@3241:     variable.
edouard@3241: 
edouard@3241:     Direct sub-elements can be either groups of widget to be spanned, labeled
edouard@3241:     "ClassName:offset", or buttons to control the spanning, labeled
edouard@3241:     "ClassName:+/-number".
edouard@4025: 
edouard@4025:     In case of "ClassName:offset", offset for first element is 1.
edouard@4025: 
edouard@3241:     ||
edouard@3241: 
edouard@3241:     shortdesc > span widgets over a set of repeated HMI_NODEs
edouard@3241: 
edouard@3241:     arg name="class_name" accepts="string" > HMI_CLASS name
edouard@3241: 
edouard@3241:     path name="root" accepts="HMI_NODE" >  where to find HMI_NODEs whose HMI_CLASS is class_name
edouard@4048:     path name="position" accepts="HMI_INT" > position of HMI_NODE mapped to first item, among similar siblings
edouard@4048:     path name="range" accepts="HMI_INT" count="optional" >  count of HMI_NODE siblings
edouard@4048:     path name="size" accepts="HMI_INT" count="optional" >  count of visible items
edouard@3241: }
edouard@2891: 
edouard@3232: widget_defs("ForEach") {
edouard@2894: 
edouard@4025:     if "count(path) < 1" error > ForEach widget «$hmi_element/@id» must have one HMI path given.
edouard@3005:     if "count(arg) != 1" error > ForEach widget «$hmi_element/@id» must have one argument given : a class name.
edouard@3005: 
edouard@2894:     const "class","arg[1]/@value";
edouard@2894: 
edouard@2894:     const "base_path","path/@value";
edouard@2894:     const "hmi_index_base", "$indexed_hmitree/*[@hmipath = $base_path]";
edouard@2894:     const "hmi_tree_base", "$hmitree/descendant-or-self::*[@path = $hmi_index_base/@path]";
edouard@2894:     const "hmi_tree_items", "$hmi_tree_base/*[@class = $class]";
edouard@2894:     const "hmi_index_items", "$indexed_hmitree/*[@path = $hmi_tree_items/@path]"; 
edouard@2894:     const "items_paths", "$hmi_index_items/@hmipath"; 
Edouard@2893:     |     index_pool: [
edouard@2894:     foreach "$hmi_index_items" {
edouard@2894:     |       «@index»`if "position()!=last()" > ,`
edouard@2894:     }
Edouard@2893:     |     ],
edouard@2896:     |     init: function() {
Edouard@2893:     const "prefix","concat($class,':')";
Edouard@2893:     const "buttons_regex","concat('^',$prefix,'[+\-][0-9]+')";
edouard@2896:     const "buttons", "$hmi_element/*[regexp:test(@inkscape:label, $buttons_regex)]"; 
edouard@2896:     foreach "$buttons" {
edouard@2896:         const "op","substring-after(@inkscape:label, $prefix)";
edouard@2896:     |         id("«@id»").setAttribute("onclick", "hmi_widgets['«$hmi_element/@id»'].on_click('«$op»', evt)");
Edouard@2893:     }
edouard@2896:     |
Edouard@2895:     |         this.items = [
Edouard@2893:     const "items_regex","concat('^',$prefix,'[0-9]+')";
Edouard@2893:     const "unordered_items","$hmi_element//*[regexp:test(@inkscape:label, $items_regex)]";
Edouard@2893:     foreach "$unordered_items" {
Edouard@2893:         const "elt_label","concat($prefix, string(position()))"; 
Edouard@2893:         const "elt","$unordered_items[@inkscape:label = $elt_label]";
edouard@2894:         const "pos","position()";
edouard@2894:         const "item_path", "$items_paths[$pos]";
Edouard@2895:     |           [ /* item="«$elt_label»" path="«$item_path»" */
Edouard@2893:         if "count($elt)=0" error > Missing item labeled «$elt_label» in ForEach widget «$hmi_element/@id»
edouard@4025:         if "count($elt)>1" error > Duplicate item labeled «$elt_label» in ForEach widget «$hmi_element/@id»
Edouard@2893:         foreach "func:refered_elements($elt)[@id = $hmi_elements/@id][not(@id = $elt/@id)]" {
edouard@2894:             if "not(func:is_descendant_path(func:widget(@id)/path/@value, $item_path))"
edouard@2896:                 error > Widget id="«@id»" label="«@inkscape:label»" is having wrong path. Accroding to ForEach widget ancestor id="«$hmi_element/@id»", path should be descendant of "«$item_path»".
Edouard@2895:     |             hmi_widgets["«@id»"]`if "position()!=last()" > ,`
edouard@2892:         }
Edouard@2895:     |           ]`if "position()!=last()" > ,`
edouard@2892:     }
Edouard@2895:     |         ]
Edouard@2895:     |     },
edouard@4025:     |     range: «count($hmi_index_items)»,
edouard@4025:     |     size: «count($unordered_items)»,
edouard@4025:     |     position: 0,
edouard@2891: }
edouard@2891: 
edouard@3232: widget_class("ForEach")
edouard@2952: ||
edouard@4025:     items_subscribed = false;
edouard@3005: 
edouard@3005:     unsub_items(){
edouard@4025:         if(this.items_subscribed){
edouard@4025:             for(let item of this.items){
edouard@4025:                 for(let widget of item) {
edouard@4025:                     widget.unsub();
edouard@4025:                 }
edouard@4025:             }
edouard@4025:             this.items_subscribed = false;
edouard@4025:         }
edouard@4025:     }
edouard@4025: 
edouard@4025:     unsub(){
edouard@4025:         super.unsub()
edouard@4025:         this.unsub_items();
edouard@4025:     }
edouard@4025: 
edouard@4025:     sub_items(){
edouard@4025:         if(!this.items_subscribed){
edouard@4025:             for(let i = 0; i < this.size; i++) {
edouard@4025:                 let item = this.items[i];
edouard@4025:                 let orig_item_index = this.index_pool[i];
edouard@4025:                 let item_index = this.index_pool[i+this.position];
edouard@4025:                 let item_index_offset = item_index - orig_item_index;
edouard@4025:                 if(this.relativeness[0])
edouard@4025:                     item_index_offset += this.offset;
edouard@4025:                 for(let widget of item) {
edouard@4025:                     /* all variables of all widgets in a ForEach are all relative. 
edouard@4025:                        Really.
edouard@4025: 
edouard@4025:                        TODO: allow absolute variables in ForEach widgets
edouard@4025:                     */
edouard@4025:                     widget.sub(item_index_offset, widget.indexes.map(_=>true));
edouard@4025:                 }
edouard@2952:             }
edouard@2952:         }
edouard@2952:     }
edouard@2891: 
edouard@4025:     sub(new_offset, relativeness, container_id){
edouard@4048:         let position_given = this.indexes.length > 1;
edouard@4025: 
edouard@4025:         // sub() will call apply_cache() and then dispatch()
edouard@4025:         // undefining position forces dispatch() to call apply_position()
edouard@4025:         if(position_given)
edouard@4025:             this.position = undefined;
edouard@4025:         
edouard@4025:         super.sub(new_offset, relativeness, container_id);
edouard@4025: 
edouard@4025:         // if position isn't given as a variable
edouard@4025:         // dispatch() to call apply_position() aren't called
edouard@4025:         // and items must be subscibed now.
edouard@4025:         if(!position_given)
edouard@4025:             this.sub_items();
edouard@4025: 
edouard@4025:         // as soon as subribed apply range and size once for all
edouard@4048:         if(this.indexes.length > 2)
edouard@4048:             this.apply_hmi_value(2, this.range);
edouard@4048:         if(this.indexes.length > 3)
edouard@4048:             this.apply_hmi_value(3, this.size);
edouard@3005:     }
edouard@3005: 
edouard@4025:     apply_position(new_position){
edouard@4025:         let old_position = this.position;
edouard@4025:         let limited_position = Math.round(Math.max(Math.min(new_position, this.range - this.size), 0));
edouard@4025:         if(this.position == limited_position){
edouard@4025:             return false;
edouard@4025:         }
edouard@4025:         this.unsub_items();
edouard@4025:         this.position = limited_position;
edouard@4025:         this.sub_items();
edouard@4025:         request_subscriptions_update();
edouard@4025:         jumps_need_update = true;
edouard@4025:         this.request_animate();
edouard@4025:         return true;
edouard@4025:     }
edouard@3005: 
edouard@4025:     on_click(opstr, evt) {
edouard@4025:         let new_position = eval(String(this.position)+opstr);
edouard@4025:         if(new_position + this.size > this.range) {
edouard@4025:             if(this.position + this.size == this.range)
edouard@4025:                 new_position = 0;
edouard@4025:             else
edouard@4025:                 new_position = this.range - this.size;
edouard@4025:         } else if(new_position < 0) {
edouard@4025:             if(this.position == 0)
edouard@4025:                 new_position = this.range - this.size;
edouard@4025:             else
edouard@4025:                 new_position = 0;
edouard@4025:         }
edouard@4025:         if(this.apply_position(new_position)){
edouard@4048:             this.apply_hmi_value(1, this.position);
edouard@4025:         }
edouard@4025:     }
edouard@4025: 
edouard@4025:     dispatch(value, oldval, index) {
edouard@4025:         // Only care about position, others are constants
edouard@4048:         if(index == 1){
edouard@4025:             this.apply_position(value);
edouard@4025:             if(this.position != value){
edouard@4025:                 // widget refused or apply different value, force it back
edouard@4048:                 this.apply_hmi_value(1, this.position);
edouard@2952:             }
edouard@2942:         }
edouard@2942:     }
edouard@2942: 
edouard@2952: ||
edouard@2942: