'use strict'
//One universal basic required here to get things going once loaded
let image,edge,edgemin,edgemax,imgWidth, context, imageData,oldImageData

window.onload = function () {
    //restoreDefaultValues(); //Un-comment this if you want to start with defaults
    document.getElementById('Load').addEventListener('click', clearOldName, false);
    document.getElementById('Load').addEventListener('change', handleFileSelect, false);

    loadAndDrawImage("img/Test.png")
    Main();
};
//Any global variables go here


//Main is hard wired as THE place to start calculating when input changes
//It does no calculations itself, it merely sets them up, sends off variables, gets results and, if necessary, plots them.
function Main() {
    saveSettings();

    //Send all the inputs as a structured object
    //If you need to convert to, say, SI units, do it here!
    const inputs = {
        h: sliders.Slideh.value / 1e3,
        b: sliders.Slideb.value / 1e3,
        delta: sliders.Slidedelta.value * 1e3,
        sigma: sliders.Slidesigma.value / 1e3,
        mm: sliders.Slidemm.value,
        Xrange: sliders.SlideXrange.value,
        Yrange: sliders.SlideYrange.value,
    }

    //Send inputs off to CalcIt where the names are instantly available
    //Get all the resonses as an object, result
    const result = CalcIt(inputs)

    //Set all the text box outputs
    document.getElementById('Volume').value = result.Volume
    document.getElementById('Width').value = result.Width

    //Do all relevant plots by calling plotIt - if there's no plot, nothing happens
    //plotIt is part of the app infrastructure in app.new.js
    if (result.plots) {
        for (let i = 0; i < result.plots.length; i++) {
            plotIt(result.plots[i], result.canvas[i]);
        }
    }

    //You might have some other stuff to do here, but for most apps that's it for CalcIt!
}

//Here's the app calculation
//The inputs are just the names provided - their order in the curly brackets is unimportant!
//By convention the input values are provided with the correct units within Main
function CalcIt({ h, b, delta, sigma,mm,Xrange,Yrange }) {
    if (oldImageData!=null) DoStuff()
    let tmp = [], DPlot = [],EPlot=[], z = h, x = 0, phi = 0, Volume = 0,  R = 2 * b, dz = 0
    const phiinc = 0.001,pi = Math.PI, g = 9.81, dgs = delta * g / sigma
    let maxWidth = 0
    for (phi = 0; phi < pi; phi += phiinc) {
        tmp.push({ x: x * 1e3, y: -z * 1e3 })
        x += R * Math.cos(phi) * phiinc
        maxWidth = Math.max(x, maxWidth)
        dz = R * Math.sin(phi) * phiinc
        z -= dz
        R = 1 / (dgs * (h - z) + 2 / b - Math.sin(phi) / x)
        Volume += pi * dz * x * x
        if (z < 0) break
    }
    const tl = tmp.length - 1
    for (let i = 0; i <= tl; i++) {
        DPlot.push({ x: -tmp[tl - i].x, y: tmp[tl - i].y })
    }
    for (let i = 0; i < tmp.length; i++) {
        DPlot.push({ x: tmp[i].x, y: tmp[i].y })
    }
    //Now plot the edge, suitable scales/centered
    if (edge){
        const mmW=mm/imgWidth
        const correction=mm/2+(edgemin*mmW-edgemax*mmW)/2
    for (let i=0; i threshold) {
                data[pos] = 255; data[pos + 1] = 255; data[pos + 2] = 255
            }
            else {
                data[pos] = 0; data[pos + 1] = 0; data[pos + 2] = 0
            }
        }
    }
    edge=[], edgemin=xSize;edgemax=0
    for (y = 1; y < ySize - 1; y++) {
        for (x = 1; x < xSize - 1; x++) {
            pos = (y * xSize + x) * 4;
            if (data[pos - 4] > data[pos] + 127) {
                edge.push({x:x,y:y})
                edgemin=Math.min(edgemin,x)
                break
            }
        }
    }
    for (y = ySize-1; y > 0; y--) {
        for (x = xSize - 1; x >0 ; x--) {
            pos = (y * xSize + x) * 4;
            if (data[pos ] > data[pos-4] + 127) {
                edge.push({x:x,y:y})
                edgemax=Math.max(edgemax,x)
                break
            }
        }
    }
    edgemax=xSize-edgemax
   if (! document.getElementById("Original").checked) context.putImageData(imageData, 0, 0)

}
function clearOldName() { //This is needed because otherwise you can't re-load the same file name!
    document.getElementById('Load').value = ""
}
function handleFileSelect(evt) {
    var f = evt.target.files[0];
    if (f) {
        if (f.type !== '' && !f.type.match('image.*')) {
            return;
        }
        // The URL API is vendor prefixed in Chrome
        window.URL = window.URL || window.webkitURL;
    
        // Create a data URL from the image file
        var imageURL = window.URL.createObjectURL(f);
    
        loadAndDrawImage(imageURL);
       }
}