+/**********************************************************************
+ * Title: PDosage
+ * Description: Pediatric Calculator
+ * Author: Agnibho Mondal
+ * Website: http://code.agnibho.com
+ **********************************************************************
+ Copyright (c) 2016 Agnibho Mondal
+ All rights reserved
+ **********************************************************************
+ This file is part of PDosage.
+
+ PDosage is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ PDosage is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with PDosage. If not, see <http://www.gnu.org/licenses/>.
+ **********************************************************************/
+
+export default function Dosage(data){
+
+ Object.defineProperty(data, "prop", {
+ writable: false
+ });
+
+ this.get=function(){
+ return data;
+ }
+
+ this.listDrugs=function(){
+ var list=data.map(function(obj){
+ return obj.name;
+ });
+ return list;
+ }
+
+ this.getDrug=function(name, patient){
+ if(this.listDrugs().indexOf(name)==-1){
+ return null;
+ }
+ var drug=JSON.parse(JSON.stringify(data.filter(extract)[0]));
+ function extract(obj){
+ return (obj.name == name);
+ }
+ for(var i=0; i<drug.form.length; i++){
+ drug.form[i]=calculateDose(drug.form[i], patient);
+ }
+ return drug;
+ }
+
+ function calculateDose(form, patient){
+ while(form.hasOwnProperty("range")){
+ var res=isolateRange(form, patient);
+ delete form.range;
+ if(res!=null){
+ if(res.hasOwnProperty("range")){
+ form.range=res.range;
+ }
+ else{
+ form.dose=res.dose;
+ }
+ }
+ }
+ if(form.dose){
+ form.dose=[].concat(form.dose);
+ for(var i=0; i<form.dose.length; i++){
+ if(form.dose[i].hasOwnProperty("val")){
+ form.dose[i].val=[].concat(form.dose[i].val);
+ }
+ else if(form.dose[i].hasOwnProperty("perKg")){
+ form.dose[i].perKg=[].concat(form.dose[i].perKg);
+ form.dose[i].val=[];
+ form.dose[i].val[0]=Math.round(parseFloat(form.dose[i].perKg[0])*parseFloat(patient.wt)*100)/100;
+ form.dose[i].val[1]=Math.round(parseFloat(form.dose[i].perKg[1])*parseFloat(patient.wt)*100)/100;
+ form.dose[i]=setLimit(form.dose[i]);
+ }
+ else if(form.dose[i].hasOwnProperty("approx")){
+ form.dose[i].val=[];
+ form.dose[i].val=findApprox(form.dose[i].approx);
+ form.dose[i]=setLimit(form.dose[i]);
+ }
+ else if(form.dose[i].hasOwnProperty("eq")){
+ form.dose[i].eq=[].concat(form.dose[i].eq);
+ form.dose[i].val=[];
+ form.dose[i].val[0]=solveEq(form.dose[i].eq[0]);
+ form.dose[i].val[1]=solveEq(form.dose[i].eq[1]);
+ form.dose[i]=setLimit(form.dose[i]);
+ }
+ else{
+ form.dose[i].val=[];
+ form.dose[i].val[0]=null;
+ form.dose[i].val[1]=null;
+ }
+ }
+ }
+ return form;
+
+ function isolateRange(form, patient){
+ var min=0;
+ var max=0;
+ var type="";
+ if(patient.age.y===null && patient.age.m===null && patient.age.d===null){
+ return null;
+ }
+ var pDays=patient.age.y*365+patient.age.m*30+patient.age.d;
+ for(var i=0; i<form.range.length; i++){
+ if(form.range[i].hasOwnProperty("min")){
+ if(form.range[i].min.indexOf("kg")!=-1){
+ min=form.range[i].min.slice(0, str.indexOf("kg"));
+ type="wt";
+ }
+ else{
+ min=strToDays(form.range[i].min);
+ type="age";
+ }
+ }
+ else{
+ min=0;
+ }
+ if(form.range[i].hasOwnProperty("max")){
+ if(form.range[i].max.indexOf("kg")!=-1){
+ max=form.range[i].max.slice(0, str.indexOf("kg"));
+ type="wt";
+ }
+ else{
+ max=strToDays(form.range[i].max);
+ type="age";
+ }
+ }
+ else{
+ max=Infinity;
+ }
+ if(type=="wt"){
+ if(patient.wt>=min && patient.wt<max){
+ return form.range[i];
+ }
+ }
+ else if(type=="age"){
+ if(pDays>=min && pDays<max){
+ return form.range[i];
+ }
+ }
+ }
+ return null;
+
+ function strToDays(str){
+ var age={y: 0, m: 0, d: 0};
+ var days=0;
+ str=str.replace(/\s+/g, "");
+ if(str.indexOf("y")!=-1){
+ age.y=str.slice(0, str.indexOf("y"));
+ str=str.slice(str.indexOf("y", -1));
+ }
+ if(str.indexOf("m")!=-1){
+ age.m=str.slice(0, str.indexOf("m"));
+ str=str.slice(str.indexOf("m", -1));
+ }
+ if(str.indexOf("d")!=-1){
+ age.d=str.slice(0, str.indexOf("d"));
+ str=str.slice(str.indexOf("d", -1));
+ }
+ days=age.y*365+age.m*30+age.d;
+ return days;
+ }
+ }
+
+ function findApprox(arr){
+ var ret=[];
+ arr[0]=arr[0]/2;
+ for(var i=1; i<arr.length; i++){
+ arr[i]=solveEq(arr[i]);
+ ret[i-1]=Math.round(arr[i]/arr[0])/2;
+ }
+ if(!ret[0] || (ret[0]==ret[1])){
+ ret[0]=ret[1];
+ ret[1]=null;
+ }
+ return ret;
+ }
+
+ function solveEq(str){
+ var bw=parseFloat(patient.wt);
+ var ageY=patient.age.y;
+ var ageM=ageY*12+patient.age.m;
+ var ageD=ageM*30+patient.age.d;
+ var ret=eval(str);
+ ret=Math.round(ret*100)/100;
+ return ret;
+ }
+
+ function setLimit(dose){
+ if(dose.adult && dose.val){
+ if(dose.val[0]>dose.adult[0]){
+ dose.val[0]=dose.adult[0];
+ }
+ if(dose.val[1]>dose.adult[1]){
+ dose.val[1]=dose.adult[1];
+ }
+ }
+ if(dose.limit && dose.val){
+ if(dose.val[0]>dose.limit[0]){
+ dose.val[0]=dose.limit[0];
+ }
+ if(dose.val[1]>dose.limit[1]){
+ dose.val[1]=dose.limit[1];
+ }
+ }
+ if(dose.val[1]==dose.val[0]){
+ dose.val[1]=null;
+ }
+ return dose;
+ }
+ }
+}