src/dosage.js

   1 /**********************************************************************
   2  * Title: PDosage
   3  * Description: Pediatric Calculator
   4  * Author: Agnibho Mondal
   5  * Website: http://code.agnibho.com
   6  **********************************************************************
   7    Copyright (c) 2016 Agnibho Mondal
   8    All rights reserved
   9  **********************************************************************
  10    This file is part of PDosage.
  11
  12    PDosage is free software: you can redistribute it and/or modify
  13    it under the terms of the GNU General Public License as published by
  14    the Free Software Foundation, either version 3 of the License, or
  15    (at your option) any later version.
  16
  17    PDosage is distributed in the hope that it will be useful,
  18    but WITHOUT ANY WARRANTY; without even the implied warranty of
  19    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20    GNU General Public License for more details.
  21
  22    You should have received a copy of the GNU General Public License
  23    along with PDosage. If not, see <http://www.gnu.org/licenses/>.
  24  **********************************************************************/
  25
  26 export default function Dosage(data){
  27
  28     Object.defineProperty(data, "prop", {
  29         writable: false
  30     });
  31
  32     this.get=function(){
  33         return data;
  34     }
  35
  36     this.listDrugs=function(){
  37         var list=data.map(function(obj){
  38             return obj.name;
  39         });
  40         return list;
  41     }
  42
  43     this.getDrug=function(name, patient){
  44         if(this.listDrugs().indexOf(name)==-1){
  45             return null;
  46         }
  47         var drug=JSON.parse(JSON.stringify(data.filter(extract)[0]));
  48         function extract(obj){
  49             return (obj.name == name);
  50         }
  51         for(var i=0; i<drug.form.length; i++){
  52             drug.form[i]=calculateDose(drug.form[i], patient);
  53         }
  54         return drug;
  55     }
  56
  57     function calculateDose(form, patient){
  58         while(form.hasOwnProperty("range")){
  59             var res=isolateRange(form, patient);
  60             delete form.range;
  61             if(res!=null){
  62                 if(res.hasOwnProperty("range")){
  63                     form.range=res.range;
  64                 }
  65                 else{
  66                     form.dose=res.dose;
  67                 }
  68             }
  69         }
  70         if(form.dose){
  71             form.dose=[].concat(form.dose);
  72             for(var i=0; i<form.dose.length; i++){
  73                 if(form.dose[i].hasOwnProperty("val")){
  74                     form.dose[i].val=[].concat(form.dose[i].val);
  75                 }
  76                 else if(form.dose[i].hasOwnProperty("perKg")){
  77                     form.dose[i].perKg=[].concat(form.dose[i].perKg);
  78                     form.dose[i].val=[];
  79                     form.dose[i].val[0]=Math.round(parseFloat(form.dose[i].perKg[0])*parseFloat(patient.wt)*100)/100;
  80                     form.dose[i].val[1]=Math.round(parseFloat(form.dose[i].perKg[1])*parseFloat(patient.wt)*100)/100;
  81                     form.dose[i]=setLimit(form.dose[i]);
  82                 }
  83                 else if(form.dose[i].hasOwnProperty("approx")){
  84                     form.dose[i].val=[];
  85                     form.dose[i].val=findApprox(form.dose[i].approx);
  86                     form.dose[i]=setLimit(form.dose[i]);
  87                 }
  88                 else if(form.dose[i].hasOwnProperty("eq")){
  89                     form.dose[i].eq=[].concat(form.dose[i].eq);
  90                     form.dose[i].val=[];
  91                     form.dose[i].val[0]=solveEq(form.dose[i].eq[0]);
  92                     form.dose[i].val[1]=solveEq(form.dose[i].eq[1]);
  93                     form.dose[i]=setLimit(form.dose[i]);
  94                 }
  95                 else{
  96                     form.dose[i].val=[];
  97                     form.dose[i].val[0]=null;
  98                     form.dose[i].val[1]=null;
  99                 }
 100             }
 101         }
 102         return form;
 103
 104         function isolateRange(form, patient){
 105             var min=0;
 106             var max=0;
 107             var type="";
 108             var pDays=patient.age.y*365+patient.age.m*30+patient.age.d;
 109             for(var i=0; i<form.range.length; i++){
 110                 if(form.range[i].hasOwnProperty("min")){
 111                     if(form.range[i].min.indexOf("kg")!=-1){
 112                         min=form.range[i].min.slice(0, str.indexOf("kg"));
 113                         type="wt";
 114                     }
 115                     else{
 116                         min=strToDays(form.range[i].min);
 117                         type="age";
 118                     }
 119                 }
 120                 else{
 121                     min=0;
 122                 }
 123                 if(form.range[i].hasOwnProperty("max")){
 124                     if(form.range[i].max.indexOf("kg")!=-1){
 125                         max=form.range[i].max.slice(0, str.indexOf("kg"));
 126                         type="wt";
 127                     }
 128                     else{
 129                         max=strToDays(form.range[i].max);
 130                         type="age";
 131                     }
 132                 }
 133                 else{
 134                     max=Infinity;
 135                 }
 136                 if(type=="wt"){
 137                     if(patient.wt>=min && patient.wt<max){
 138                         return form.range[i];
 139                     }
 140                 }
 141                 else if(type=="age"){
 142                     if(pDays>=min && pDays<max){
 143                         return form.range[i];
 144                     }
 145                 }
 146             }
 147             return null;
 148
 149             function strToDays(str){
 150                 var age={y: 0, m: 0, d: 0};
 151                 var days=0;
 152                 str=str.replace(/\s+/g, "");
 153                 if(str.indexOf("y")!=-1){
 154                     age.y=str.slice(0, str.indexOf("y"));
 155                     str=str.slice(str.indexOf("y", -1));
 156                 }
 157                 if(str.indexOf("m")!=-1){
 158                     age.m=str.slice(0, str.indexOf("m"));
 159                     str=str.slice(str.indexOf("m", -1));
 160                 }
 161                 if(str.indexOf("d")!=-1){
 162                     age.d=str.slice(0, str.indexOf("d"));
 163                     str=str.slice(str.indexOf("d", -1));
 164                 }
 165                 days=age.y*365+age.m*30+age.d;
 166                 return days;
 167             }
 168         }
 169
 170         function findApprox(arr){
 171             var ret=[];
 172             arr[0]=arr[0]/2;
 173             for(var i=1; i<arr.length; i++){
 174                 arr[i]=solveEq(arr[i]);
 175                 ret[i-1]=Math.round(arr[i]/arr[0])/2;
 176             }
 177             if(!ret[0] || (ret[0]==ret[1])){
 178                 ret[0]=ret[1];
 179                 ret[1]=null;
 180             }
 181             return ret;
 182         }
 183
 184         function solveEq(str){
 185             var bw=parseFloat(patient.wt);
 186             var ageY=patient.age.y;
 187             var ageM=ageY*12+patient.age.m;
 188             var ageD=ageM*30+patient.age.d;
 189             var ret=eval(str);
 190             ret=Math.round(ret*100)/100;
 191             return ret;
 192         }
 193
 194         function setLimit(dose){
 195             //console.log(">>"+JSON.stringify(dose));
 196             if(dose.limit && dose.val){
 197                 if(dose.val[0]>dose.limit[0]){
 198                     dose.val[0]=dose.limit[0];
 199                 }
 200                 if(dose.val[1]>dose.limit[1]){
 201                     dose.val[1]=dose.limit[1];
 202                 }
 203             }
 204             if(dose.val[1]==dose.val[0]){
 205                 dose.val[1]=null;
 206             }
 207             return dose;
 208         }
 209     }
 210 }