var express = require('express')
var bodyParser = require('body-parser');
const fs = require('fs');
var app = express()
var request = require('request')
app.use(bodyParser.json())

var cors = require('cors')
app.use(cors())

app.post('/readFile', (req, res) => {
  var fileNameReceived = req.body.path
  var startLine = req.body.startLine
  var endLine = req.body.endLine
  var putAfterLine = req.body.putAfterLine
  if (fileNameReceived == null) {
    return res.send('bad')
  } else {
    fs.readFile(fileNameReceived, (err, data) => {
      if (err != null) {
        console.log("err, not null, is: " + JSON.stringify(err))
      }
      if (data != null) {
        console.log("data: \n" + data)
        console.log("\n\n line by line:\n")
        var lines = data.toString().split('\n')
        data.toString().split("\n").forEach((line, index) => {
          console.log(`${line}`)
        })
        if (startLine != null && endLine != null && putAfterLine != null) {
          var linesRemovedLength = parseInt(endLine) - parseInt(startLine) + 1
          var linesPlacedElsewhere = lines.splice(parseInt(startLine) - 1, parseInt(endLine) - parseInt(startLine) + 1)
          for (var i = 0; i < linesPlacedElsewhere.length; i++) {
            lines.splice(parseInt(putAfterLine) - linesRemovedLength, 0, linesPlacedElsewhere[i])
          }
          // lines.splice(parseInt(putAfterLine) - linesRemovedLength, 0, linesPlacedElsewhere);
          console.log(`what file would look like after placing lines ${startLine}-${endLine} after line ${putAfterLine}:`)
          lines.forEach((line, index) => {
            console.log(`${line}`)
          })
        }
      }
      console.log("\n\n\n")
      return res.send('good')
    })
  }
})

var port = 63136
app.listen(process.env.PORT || port, function () {
  console.log(`Listening on port ${process.env.PORT || port}`);
});