roll20-character-sheets/rapidfire_system/scaffold/attribute_proxy.js

/*jshint esversion: 11, laxcomma:true, eqeqeq:true*/
/*jshint -W014,-W084,-W030,-W033*/
//# Attribute Obj Proxy handler
const createAttrProxy = function(attrs){
  //creates a proxy for the attributes object so that values can be worked with more easily.
  const getCascObj = function(event,casc){
    let typePrefix = event.htmlAttributes ? 'act_' : 'attr_';
    let cascName = `${typePrefix}${event.sourceAttribute}`;
    let cascObj = casc[cascName];
    return cascObj;
  };
  
  const triggerFunctions = function(obj,attributes,sections){
    if(obj.triggeredFuncs && obj.triggeredFuncs.length){
      debug(`triggering functions for ${obj.name}`);
      obj.triggeredFuncs && obj.triggeredFuncs.forEach(func=>funcs[func] ? 
        funcs[func]({trigger:obj,attributes,sections}) :
        debug(`!!!Warning!!! no function named ${func} found. Triggered function not called for ${obj.name}`,true));
    }
  };
  
  const initialFunction = function(obj,attributes,sections){
    if(obj.initialFunc){
      debug(`initial functions for ${obj.name}`);
      funcs[obj.initialFunc] ?
        funcs[obj.initialFunc]({trigger:obj,attributes,sections}) :
        debug(`!!!Warning!!! no function named ${obj.initialFunc} found. Initial function not called for ${obj.name}`,true);
    }
  };
  const processChange = function({event,trigger,attributes,sections,casc}){
    debug({trigger});
    if(event && !trigger){
      debug('initial change detected. No trigger found');
      return;
    }
    if(!attributes || !sections || !casc){
      debug(`!!! Insufficient arguments || attributes > ${!!attributes} | sections > ${!!sections} | casc > ${!!casc} !!!`);
      return;
    }
    //store the queue in attributes.
    if(event){
      debug('checking for initial functions');
      initialFunction(trigger,attributes,sections);//functions that should only be run if the attribute was the thing changed by the user
      attributes.queue = [...trigger.affects];
    }
    if(trigger){
      debug(`processing ${trigger.name}`);
      triggerFunctions(trigger,attributes,sections);
      if(!event && trigger.calculation){
        attributes[trigger.name] = funcs[trigger.calculation]({trigger,attributes,sections});
      }
    }
    if(event || attributes.updates.hasOwnProperty(trigger.name)){
      attributes.queue.push(...trigger.affects);
    }
    attributes.set({attributes,sections,casc});
  };
  const attrTarget = {
    updates:{},
    attributes:{...attrs},
    repOrders:{},
    queue: [],
    casc:{},
    processChange,
    triggerFunctions,
    initialFunction,
    getCascObj
  };
  const attrHandler = {
    get:function(obj,prop){//gets the most value of the attribute.
      //If it is a repeating order, returns the array, otherwise returns the update value or the original value
      if(prop === 'set'){
        return function(){
          let {attributes,sections,casc,callback,vocal} = arguments[0] ? arguments[0] : {};
          if(attributes && attributes.queue.length && sections && casc){
            let triggerName = attributes.queue.shift();
            let trigger = getCascObj({sourceAttribute:triggerName},casc);
            attributes.processChange({trigger,attributes,sections,casc});
          }else{
            debug('sheet accessed, all changes handled, setting attributes');
            set(obj.updates,vocal,callback);
          }
        }
      }else if(Object.keys(obj).some(key=>key===prop)){ 
        return Reflect.get(...arguments)
      }else{
        let retValue;
        switch(true){
          case obj.repOrders.hasOwnProperty(prop):
            retValue = obj.repOrders[prop];
            break;
          case obj.updates.hasOwnProperty(prop):
            retValue = obj.updates[prop];
            break;
          default:
            retValue = obj.attributes[prop];
            break;
        }
        let cascRef = `attr_${prop.replace(/(repeating_[^_]+_)[^_]+/,'$1\$x')}`;
        let numRetVal = +retValue;
        if(!Number.isNaN(numRetVal)){
          retValue = numRetVal;
        }else if(cascades[cascRef] && typeof cascades[cascRef].defaultValue === 'number'){
          retValue = cascades[cascRef].defaultValue;
        }
        return retValue;
      }
    },
    set:function(obj,prop,value){
      //Sets the value. Also verifies that the value is a valid attribute value
      //e.g. not undefined, null, or NaN
      if(value || value===0 || value===''){
        if(/reporder|^repeating_[^_]+$/.test(prop)){
          let section = prop.replace(/_reporder_/,'');
          obj.repOrders[section] = value;
        }else if(`${obj.attributes}` !== `${value}` || 
          (obj.updates[prop] && `${obj.updates}` !== `${value}`)
        ){
          obj.updates[prop] = value;
        }
      }else{
        debug(`!!!Warning: Attempted to set ${prop} to an invalid value:${value}; value not stored!!!`);
      }
      return true;
    },
    deleteProperty(obj,prop){
      //removes the property from the original attributes, updates, and the reporders
      Object.keys(obj).forEach((key)=>{
        delete obj[key][prop.toLowerCase()];
      });
    }
  };
  return new Proxy(attrTarget,attrHandler);
};

const funcs = new Proxy({},{
  set:function(obj,prop,value){
    if(obj[prop]){
      debug(`!!! Duplicate function name for ${prop} !!!`);
      return false;
    }else{
      obj[prop] = value;
      return true;
    }
  },
  get:function(obj,prop){
    return function(){
      debug(`running ${prop}`);
      return obj[prop](...arguments);
    };
  }
});