// Run when changes are detected in input text areas
document.getElementById("packageConfig").addEventListener('input',generate);
document.getElementById("csproj").addEventListener('input',generate);


function generate(){
  // Clear error messages
  document.getElementById("csprojErrorField").innerHtml = "";  
  document.getElementById("packageConfigErrorField").innerHtml = "";

  // Parse xml document and get all package tags
  var packages = getPackageArray();
  var projectReferences = getProjectReferenceArray();
  
  // Build new xml document containing packages
  var xml = buildNewConfigFile(packages,projectReferences);
  // Serialize xml document to string and output
  var serializer = new XMLSerializer();
  document.getElementById("output").value = serializer.serializeToString(xml);
}

function buildNewConfigFile(packages,projects){
  // Need xml document to create tags
  var xml = document.implementation.createDocument(null,"dontneed");
  // Create root tag with attribute
  var root = xml.createElement("Project");
  root.setAttribute("Sdk","Microsoft.NET.Sdk");
  
  // Set target framework
  var targetFramework = xml.createElement("TargetFramework");
  targetFramework.textContent = "netstandard" + getDotnetVersion();
  var propertyGroup = xml.createElement("PropertyGroup");
  propertyGroup.appendChild(targetFramework);
  root.appendChild(propertyGroup);
  
  // Add all packages
  var itemGroup = xml.createElement("ItemGroup");
  for(const p of packages){    
    var packageReference = xml.createElement("PackageReference");
    packageReference.setAttribute("Include",p.name);
    packageReference.setAttribute("Version",p.version);
    itemGroup.appendChild(packageReference);
  }
  root.appendChild(itemGroup);
  
  var projectItemGroup = xml.createElement("ItemGroup");
  for(const p of projects){
    var projectReference = xml.createElement("ProjectReference");
    projectReference.setAttribute("Include",p);
    projectItemGroup.appendChild(projectReference);
  }
  root.appendChild(projectItemGroup);
  return root;
}

function getPackageArray(){
  var packages = [];
  const inputstring = document.getElementById("packageConfig").value;
  const xml = new window.DOMParser().parseFromString(inputstring,"text/xml");
  if(inputstring.length != 0)
  checkXmlForErrors(xml,"packageConfigErrorField");
  // Find all elements with tag name package
  const xmlElements = xml.getElementsByTagName('package');
  for(const x of xmlElements){
    // Create obj for each package
    var package = {
      name: x.getAttribute("id"),
      version: x.getAttribute("version")
    };
    packages.push(package);
  }
  return packages;
}

function getProjectReferenceArray(){
    var projectPaths = [];
  const inputstring = document.getElementById("csproj").value;
    var xml = new window.DOMParser().parseFromString(inputstring,"text/xml");
    if(inputstring.length != 0)
    checkXmlForErrors(xml,"csprojErrorField");
// Find all elements with tag name ProjectReference
  const xmlElements = xml.getElementsByTagName('ProjectReference');
  for(const e of xmlElements){
    projectPaths.push(e.getAttribute("Include"));
  }
  return projectPaths;
}

function checkXmlForErrors(xml, errorOutputFieldId){
  var error = xml.getElementsByTagName("parsererror")[0];
  if(error){
    var errorMsg = error.getElementsByTagName("div")[0].textContent
    document.getElementById(errorOutputFieldId).innerHTML = errorMsg;
  }
  else{
        document.getElementById(errorOutputFieldId).innerHTML = "";
  }
}

function mapStandard(version){
  var versionNumber = version.replace(/[^0-9.]/g, "");
  switch(parseInt(versionNumber)){
    case 31:
    case 49:
    case 78:
    case 84:
    case 157:
    case 259:
      return "1.0";
    case 7:
    case 111:
      return "1.1";
    case 32:
    case 44:
    case 151:
      return "1.2";
      //When in doubt. Go for 2.0
    default:
      return "2.0";
  }
}

function getDotnetVersion(){
  const inputstring = document.getElementById("csproj").value;
  const xml = new window.DOMParser().parseFromString(inputstring,"text/xml");
  if(inputstring.length != 0)
  checkXmlForErrors(xml,"packageConfigErrorField");
  // Find all elements with tag name package
  const xmlElements = xml.getElementsByTagName('TargetFrameworkProfile');
  
  return mapStandard(xmlElements[0].innerHTML);
}