var BUILD_VERSION = '[VI]Version: {version} - built on {date}[/VI]';
var runtimestamp = (new Date()).getTime();
function getVersion() { return BUILD_VERSION; }
WScript.echo(getVersion())

var fso = new ActiveXObject('Scripting.FileSystemObject');
var shell = new ActiveXObject('shell.application'); 
function forEach(eachFn){
  for(var i=0; i<this.length; i++) eachFn(this[i])
}

var console = { log : function(m) {WScript.Echo(m)}, error : function(m) {WScript.Echo(m)} }
var Promise = function(fn){

  // Detect error
  var state = Promise.PENDING;
  var chain = [];
  chain.forEach = forEach;

  function reject(e){ 
    if(state !== Promise.PENDING) { console.error ('Error : Promise Rejection can only be called once')}
    var __i = 0;
    var __e = e;
    do {
      for(var i = __i; i < chain.length; i++, __i = i) if(chain[i].isCatch) break;
      try {
        for(var i = __i; i < chain.length; i++, __i = i) if(chain[i].isCatch) { chain[i](__e); break; } 
        __e = null;
      }
      catch(e){ __e = e}
    } while(__e)
    do {
      try { for(var i = __i; i < chain.length; i++, __i = i) if(!chain[i].isCatch) { p.result = chain[i](p.result); } }
      catch(e){ 
        do {
          try {
            for(var i = __i; i < chain.length; i++, __i = i) if(chain[i].isCatch) { chain[i](__e); break; } 
            __e = null;
          }
          catch(e){ __e = e}
        } while(__e)
      } 
    } while ( __i < chain.length )
    state = Promise.REJECTED;
  }

  function resolve(result){   
    if(state !== Promise.PENDING) { console.error ('Error : Promise Rejection can only be called once')}
    // console.log('main promise resolve... ' + chain.length )
    p.result = result;
    var __i = 0;
    do {
      try { for(var i = __i; i < chain.length; i++, __i = i) if(!chain[i].isCatch) { p.result = chain[i](p.result); } }
      catch(e){ 
        var __e = e;
        do {
          try {
            for(var i = __i; i < chain.length; i++, __i = i) if(chain[i].isCatch) { chain[i](__e); break; } 
            __e = null;
          }
          catch(e){ __e = e}
        } while(__e)
      } 
    } while ( __i < chain.length )
    state = Promise.FULFILLED;
  };
  
  var p = { 
    then : function(thenfn){ 
      thenfn.isThen = true
      chain.push(thenfn)
      return p;
    }
    , pcatch : function(catchfn) {
      catchfn.isCatch = true
      chain.push(catchfn)
      return p;
    }
    , start : function(){
      try { fn(resolve, reject) }
      catch(e){ reject(e) }
    }
  }
  return p
}

Promise.all = function(arr){
  arr.forEach = forEach;
  var results = [];
  return new Promise(function(resolve, reject){
    arr.forEach(function(p){ results.push(waitForResult(p))} )
    resolve(results)
  });
}

any = function(arr){
  arr.forEach = forEach;
  var results = [];
  return new Promise(function(resolve, reject){
    arr.forEach(function(p){ results.push(waitForResult(p))} )
    resolve(results)
  });
}

Promise.PENDING = 1
Promise.FULFILLED = 2
Promise.REJECTED = 3


function waitForResult(p){
  while(p.state === Promise.PENDING) WScript.Sleep(500)
  return true
}

var stampedFilePfx = function(date) {
  return date.getFullYear() +
  ('0' + (date.getMonth() + 1)).slice(-2) + 
  ('0' + date.getDate()).slice(-2) +
  ('0' + date.getHours()).slice(-2) +
  ('0' + date.getMinutes()).slice(-2) +
  ('0' + date.getSeconds()).slice(-2);
}
function nodeShellExec(cmd, cargs){
  
  var p = new Promise(function(resolve, reject){
    var runFile = selectedinstance.root + '\\' + stampedFilePfx(new Date()) + cmd + cargs + "out.txt";
    // console.log(runFile)
    shell.ShellExecute('cmd', '/c ' + cmd + ' ' + cargs + " > " + runFile , "", "", 1);
    // var WshFinished = 1
    // var WshFailed = 2
    // var strOutput = 'Did not work'
    // switch(shell.Status){
    //   case WshFinished : 
    //     strOutput = oShell.StdOut.ReadAll;
    //     break;
    //   case WshFailed :
    //     strOutput = oShell.StdErr.ReadAll;
    //     break;
    // }
    // WScript.Echo(strOutput)

    while(!fso.FileExists(runFile)) {
      WScript.Sleep(500)
    }

    var objFileToRead = fso.OpenTextFile(runFile,1)
    var strFileText = objFileToRead.ReadAll()
    objFileToRead.Close()

    fso.DeleteFile(runFile)
    resolve(strFileText)
  })
  
  return p;
} 

// Detect or specify install directory.
var selectedinstance = {
  root : fso.GetAbsolutePathName(".")
}

var downloadsdir = selectedinstance.root + '/Downloads';

var fs = {
  writeFileSync : function(filepath, text) {
    WScript.echo(filepath)    
    var fh = fso.CreateTextFile(filepath, true); 
    fh.WriteLine(text); 
    fh.Close(); 
  },
  existsSync : function(path){
    // fso.FileExists(path)
    return fso.FolderExists(path)
  }
  , mkdirSync : function(path) {
    fso.CreateFolder(path)
  }
}

var path = {
  dirname : function(filepath) {
    var normalized = filepath.replace(/\//g,'\\');
    var li = normalized.lastIndexOf("\\")
    if( li > -1) {
      return normalized.substring(0, li)
    }
  }
}

function ensureDirectoryExistence(filePath) {
  var dirname = path.dirname(filePath);
  if (fs.existsSync(dirname)) {
    return filePath;
  }
  ensureDirectoryExistence(dirname);
  fs.mkdirSync(dirname);
  return filePath;
}

var getTaskCheckExists = function(command, options) {
  options = options || {}
  return function() {
    var p = nodeShellExec.apply(null, ['where', [command]])
    if (options.ignorefailures) {
      return p.then(function(v) { 
        // WScript.Echo('firstThen ' + v);
        return v }).pcatch( function(e) { // Ignore. Not a major error.
        return false;
      })
    }
    else return p.then(function() { 
      // WScript.Echo('firstThen ddd'); 
      return v });
  }
}

function verifyAndInstallPrerequisites() {
  fs.writeFileSync(ensureDirectoryExistence(downloadsdir + '/readme.txt'), getVersion() + ' Your local downloads for this instance');
  var downloadbatch =
    "::************************************************************************** \
  :Download_ <url> <File> \
    Powershell.exe ^ \
    $AllProtocols = [System.Net.SecurityProtocolType]'Ssl3,Tls,Tls11,Tls12'; ^ \
    [System.Net.ServicePointManager]::SecurityProtocol = $AllProtocols; ^ \
    (New-Object System.Net.WebClient).DownloadFile('%1','%2') \
  exit /b \
  ::**************************************************************************";
  fs.writeFileSync('download.bat', downloadbatch);

  var downloadtasks = [];
  var installtasks = [];
  prerequisites.forEach(function(preq) {
    var p = null;
    downloadtasks.push(
      p = preq.exists().then(function(exists) {
        if (exists) console.log( preq.shellcmd + ' exists');
        else {
          console.log(preq.shellcmd + ' is not installed');
          return preq.preinstallsteps().then(function(){
            installtasks.push(task.install);
          })
        }
      }
    ));
    p.start()
  });
  return Promise.all(downloadtasks).then(function(){ return any(installtasks) })
}


var prerequisites = [
  {
    shellcmd: 'git',
    url: 'https://github.com/git-for-windows/git/releases/download/v2.31.0.windows.1/Git-2.31.0-64-bit.exe'
    , installer: 'Git-2.31.0-64-bit.exe'
    , installcmd: ['cmd', ['/c', 'start',
      '/WAIT', downloadsdir + '/' + 'Git-2.31.0-64-bit.exe'
      , '/VERYSILENT'
      // , '/MERGETASKS=!runcode' // This is required only for vscode...
    ]]
    , preinstallsteps: function() {
      var prompt = cli.prompter;
      var steps = [
        function(){
          if (!existsSync(downloadsdir + '/' + this.installer)) {
            return nodeShellExec(selectedinstance.root + '/.elxr/run-${runtimestamp}/download.bat', [this.url, downloadsdir + '/' + this.installer])
          }
          else return Promise.resolve(true)
        }
      ]
      var prompts = [
        function() {prompt.ask('git user name : ( <= ' + gitUser + ' )').then( function(user){ gitUser = user; })}
        , function() { prompt.ask('git email : ( <= ' + gitEmail + ' )').then(function(email) { gitEmail = email; })}
      ]
      return any([any(steps), any(prompts)])
    }
    , installsteps: function () {
      return any([this.installcmd].map(callsheltask))
    }
    , postinstallsteps: function(){
      
      var prompt = cli.prompter;
      
      var gitUser = 'guest';
      var gitEmail = 'guest@bbh.org.in';
      var prompts = [];
      prompts.push(
        function(){
          var choices = { 0 : 'guest', 1 : 'chessdemo' }
          return cli.prompt(choices, 'git user name').then(function(gituser) { gitUser = gituser})
        }
      )

      prompts.push(
        function(){
          var choices = { 0 : 'guest@bbh.org.in', 1 : 'chessdemo@bbh.org.in' }
          return cli.prompt(choices, 'git user email').then(function(gitemail) { gitEmail = gitemail})
        }
      )

      return any(prompts).then(function(){
        var steps = [
          ['git', ['config', '--global', '--add', 'user.name', gitUser]]
          , ['git', ['config', '--global', '--add', 'user.email', gitEmail]]
        ]
        return any(steps.map(callsheltask)).then(function(){ 

        })
      });
    }
    , install: function () {
      return any([ /*this.preinstallsteps,*/ this.installsteps.bind(this), this.postinstallsteps.bind(this)])
    }
    , verifyAndInstall : function(){
      var self = this;
      return self.exists().then( function(exits) {
        if(exists) return self.getUser(null, self.postinstallsteps.bind(self))
        else return self.install();
      })
    }
    , exists : function(next){
      var self = this;
      return getTaskCheckExists(this.shellcmd, { ignorefailures: true })().then(function(exists) {
        if(exists && exists.indexOf(self.shellcmd) > -1 ) {
          // console.log(exists + '    git exists')
          return true;
        }
        else return false
      })
    }
    , getUser : function(repo, onNoResult){
      
      
      onNoResult = onNoResult || function(){return false}
      var globalOrLocal = '--global';
      if(!repo) globalOrLocal = '--global';
      else globalOrLocal = '--local'

      return any([['git', ['config', globalOrLocal, '--get-all', 'user.name']]].map(callsheltask)).then(function(result){
        // not yet configured.
        if(!result.success) return onNoResult()
        else {
          var users = result.messages[0].trim().split('\n');
          if(users.length === 0 ||
              users.length === 1 && users[0] === 'guest') {
            
            return onNoResult()
          }
          else return users[0]; // PB : TODO == We should probably prompt with all the users available for selection ! 
        }
      })
      .pcatch(function(e){ 
        console.log(e) 
        return onNoResult()
      })
    }
  }
  ,
  {
    shellcmd: 'node',
    url: 'https://nodejs.org/dist/v14.16.0/node-v14.16.0-x64.msi'
    , installer: 'node-v14.16.0-x64.msi'
    , installcmd: ['MSIEXEC.exe', ['/i'
      , downloadsdir + '/' + 'node-v14.16.0-x64.msi'
      , 'ACCEPT=YES', '/passive']]
    , install : function() { return any([this.installcmd].map(callsheltask)) }
    
    , exists : function(next){
      var self = this;
      return getTaskCheckExists(this.shellcmd, { ignorefailures: true })().then(function(exists) {
        if(exists && exists.indexOf(self.shellcmd) > -1 ) {
          // console.log(self.shellcmd + ' ' + exists + '    node exists')
          return true
        }
        else {
          // console.log(self.shellcmd + ' ' + exists + '    node doesnt exist')
          return false
        }
      })
    }
    , preinstallsteps : function(){
      return true;
    }
  }
]

prerequisites.forEach = forEach;

verifyAndInstallPrerequisites()