var http = require('http');
const fs = require('fs');
var url = require('url');
var path = require('path');
var StringDecoder = require('string_decoder').StringDecoder;
var exec = require("child_process").exec;
var Promise= require('promise');

var mimeTypes = {
     "html": "text/html",
     "jpeg": "image/jpeg",
     "jpg": "image/jpeg",
     "png": "image/png",
     "js": "text/javascript",
     "css": "text/css",
     "json": "text/plain"};

     

function writenodes(nodes) {
    
    fs.writeFile('public/Verbesserungen.txt', nodes, { flag: 'w' }, (err) => { 
    if (err) 
      console.log(err); 
    else { 
      console.log("File written successfully\n"); 
      console.log("The written has the following contents:"); 
      console.log(fs.readFileSync("public/nodes.txt", "utf8")); 
    }
})};
// function writeedges(edges) {
//     
//     fs.writeFile('public/edges.txt', edges, { flag: 'w' }, (err) => { 
//     if (err) 
//       console.log(err); 
//     else { 
//       console.log("File written successfully\n"); 
//       console.log("The written has the following contents:"); 
//       console.log(fs.readFileSync("public/edges.txt", "utf8"));
//   }
// })};
// the following read funcitons are not asyncronous, that means they will block the process.. 
// for scalability this has to be changed in future
// function readnodes() {
//     var input = fs.readFileSync('public/nodes.txt', 'utf8')
// //     console.log('input ooohyeah',input)
// // //     var danodes = JSON.parse(input);
// //     
// //     const lines = input.split(/\r?\n/);
// //     console.log('line numbaaa 1', lines, lines[1], lines[1].length)
// //     var string = '';
// //     var i;
// //     
// //     for (i = 0; i < (lines.length - 2); i++) {
// //          string += '"data' + i.toString()   + '":' + lines[i] + ' ,'  ;
// //     }; 
// //     string += '"data' + lines.length.toString()   + '":' + lines[lines.length - 2]  ;
// //     string = '{' + string + '}' ;
// //     const jsonlines = JSON.parse(string)
// //     
// //     
// //     let sortedlines = [];
// //     sortedlines = [].slice.call(jsonlines).sort(function(a,b) {
// //         var x = a.length;
// //         var y = b.length;
// //         if (x < y) {
// //             return -1;
// //         }
// //         if (x > y) {
// //             return 1;
// //         }
// //         return 0;
// // 
// //     });
// //     console.log('daline1 in nodes', sortedlines)
//     return input
// };
// function readedges() {
//     
//     var daedges = fs.readFileSync('public/edges.txt', 'utf8');
// //     const lines = daedges.split(/\r?\n/);
// // //     console.log(lines)
// //     sortedlines = lines.sort(function(a,b) {
// //         var x = a.length;
// //         var y = b.length;
// //         if (x < y) {
// //             return -1;
// //         }
// //         if (x > y) {
// //             return 1;
// //         }
// //         return 0;
// // 
// //     });
// //     console.log('daline1 in edges', sortedlines[0])
//     return daedges
// };
//      





http.createServer((request, response)=>{
    var pathname = url.parse(request.url).pathname;
    var filename;
    if(pathname === "/"){
        filename = "Prototyp.html";
    }
    else{
        filename = path.join(process.cwd(), pathname);
    }
    
    
      

    
    
    try{
        fs.accessSync(filename, fs.F_OK);
        var fileStream = fs.createReadStream(filename);
        var mimeType = mimeTypes[path.extname(filename).split(".")[1]];
        response.writeHead(200, {'Content-Type':mimeType});
        fileStream.pipe(response);  
        
        
        if (mimeType === "text/plain"){
            // Get the payload,if any
    var decoder = new StringDecoder('utf-8');
    var buffer = '';
    var theanswer = '';
    request.on('data', function(data) {
       buffer += decoder.write(data);
    });
    var theanswer = '';
    console.log('i am at least come til here')
    request.on('end', function() {
      buffer += decoder.end();
        console.log(buffer);
      if (buffer[3] === 'i'){
        
          
          
          
          
        
        console.log(buffer);
        
          
      }
      if (buffer[3] === 'f'){
        
              
          console.log(buffer);
          theanswer = 'your changes were taken into the\n\nM A T R I X'
          
          
          
      }
      
      console.log(buffer[3])
      if (buffer === 'DONE'){
        
          console.log('recieved a DONE')
          
          exec("cp /dev/null > public/data.json")
          
          
          
          
      }
        if (buffer.length > 1) {
        console.log('starting hte python code, argument is ' + buffer)
        const execpython = new Promise((resolve, reject) => {
        exec("python prototype_all_chained.py " + buffer + " > public/data.json", (error, stdout, stderr) => {
            if (error) {
                console.log(`error: ${error.message}`);
                reject(error)
            } else {
            console.log(`stdout: ${stdout}`);
            resolve(stdout)
            }
        });
    
})
        
        
        
        const checkIfItsDone = () => {
        execpython
            .then(ok => {
            console.log(ok)
            })
            .catch(err => {
            console.log(err)
            })
        }
        
        
        
        checkIfItsDone()
        }
        
//         var string = 'oi';
// //         var string = execpython('oi');
// //         console.log('output of execpython', string);
//         Promise.resolve(string)
//         .then(execpython(string))
//         .then(s => response.end(s))
        

      // Log the request/response
      console.log('Payload received: ',buffer);
    });
    
    
        }
        
    }
    catch(e) {
            console.log('File not exists: ' + filename);
            
            response.writeHead(404, {'Content-Type': 'text/plain'});
            response.write('404 Not Found\n');
            response.end();
            return;
    }
    
    return;
    }
    
).listen(8888);