Creating a custom gradient from Sample Image

I am trying to figure out the Photoshop DOM and it seems really strange to me. Here is some basic pseudocode that I thought I could just modify to work with PS, but it is not that easy I am finding.

let doc=document; //grab a reference to the current document
let cols=doc.getColumns(); //grab an array of references for 1px wide columns for the document;

let stops=[]; //these will be the gradient stops
let colCount=cols.length; //get the total count of columns
for (let colNum=0;colNum<colCount;colNum++) { //iterate through columns
    let theCol=cols[colNum]; //grab a reference to the column
    let colColor=getColorValue(theCol,[0,0]); //sample the top pixel in the column
stops.push({color:createColor(colColor), pos:createPos(colNum, colCount)});//push the color and the stop pct
}
let props={name:"testGradient"} //set any properties needed here
let grad=new PSgradient(props, stops); //creates the new gradient fill.
doc.addFill(grad); //adds the new gradient fill to the document

function getColorValue(colRef,pixelPos) {
//whatever it takes to sample the color of a column reference at a coordinate
}
function createColor(colorRef) {
    //whatever it takes to define a color in photoshop

}
function createPos (stopNum, stopCount) {
    return stopNum/stopCount; //may need to have integer stop percentages?
}