src/node-filebuffer.js
// SAGE2 is available for use under the SAGE2 Software License
//
// University of Illinois at Chicago's Electronic Visualization Laboratory (EVL)
// and University of Hawai'i at Manoa's Laboratory for Advanced Visualization and
// Applications (LAVA)
//
// See full text, terms and conditions in the LICENSE.txt included file
//
// Copyright (c) 2014
/**
* @module filebuffer
*/
"use strict";
var fs = require('fs');
var path = require('path');
var sageutils = require('../src/node-utils'); // provides utility functions
/* global */
if (!String.prototype.splice) {
/**
* The splice() method changes the content of a string by removing a range of
* characters and/or adding new characters.
*
* @this {String}
* @param {number} start Index at which to start changing the string.
* @param {number} delCount An integer indicating the number of old chars to remove.
* @param {string} newSubStr The String that is spliced in.
* @return {string} A new string with the spliced substring.
*/
String.prototype.splice = function(start, delCount, newSubStr) {
newSubStr = newSubStr || "";
return this.slice(0, start) + newSubStr + this.slice(start + Math.abs(delCount));
};
}
function MDManager() {
}
function getEntryValue(data, entryStr, delim) {
var position = data.indexOf(entryStr);
var entry = null;
var tempStr;
var tempPos = 0;
if (position > -1) {
position = position + entryStr.length;
tempStr = data.slice(position);
tempPos = tempStr.indexOf(delim);
if (tempPos > -1) {
entry = tempStr.slice(0, tempPos);
tempPos = tempPos + delim.length;
} else {
entry = tempStr;
tempPos = 0;
}
position = position + tempPos;
} else {
position = 0;
}
return {value: entry, end: position};
}
MDManager.prototype.parse = function(data) {
var owner = getEntryValue(data, ' _Owner:_ ', ' \n').value;
var color = getEntryValue(data, ' _Color:_ ', ' \n').value;
var temp = getEntryValue(data, ' _Created On:_ ', ' \n');
var createdOn = parseInt(temp.value, 10);
var texIdx = temp.end;
var text = data.slice(texIdx);
return {text: text, owner: owner, createdOn: createdOn, color: color};
};
function FileBuffer() {
this.buffers = {};
this.files = {};
this.mdManager = new MDManager();
}
function CustomBuffer(data) {
this.changeCount = 0;
this.appId = data.appId;
this.owner = data.owner;
this.createdOn = data.createdOn;
this.color = data.color;
this.str = "";
this.cursorTable = {};
this.insertMode = false;
}
CustomBuffer.prototype.insertStr = function(text, user_id) {
if (user_id !== undefined && user_id !== null) {
var caret = this.cursorTable[user_id] || 0;
}
var replace = this.insertMode ? text.length : 0;
this.str = this.str.splice(caret, replace, text);
caret = caret + text.length;
this.changeCount = this.changeCount + text.length;
var result = {index: caret - text.length, offset: text.length, deleteCount: replace, data: text, user_id: user_id};
this.cursorTable[user_id] = caret;
return result;
};
CustomBuffer.prototype.resetChange = function() {
this.changeCount = 0;
};
CustomBuffer.prototype.getData = function() {
var data = {
owner: this.owner,
createdOn: this.createdOn,
text: this.str,
color: this.color
};
return data;
};
CustomBuffer.prototype.insertChar = function(code, printable, user_id) {
var caret = this.cursorTable[user_id];
var result = {index: caret, offset: 0, deleteCount: 0, data: null, user_id: user_id};
if (printable) {
//Changing \r to \n
//Need to make this flexible enough to handle \r, \n, or \r\n
var char = (code === 13) ? '\n' : String.fromCharCode(code);
var replace = this.insertMode ? 1 : 0;
this.str = this.str.splice(caret, replace, char);
caret = caret + 1;
this.changeCount = this.changeCount + 1;
result.offset = 1;
result.data = char;
result.deleteCount = replace;
} else {
switch (code) {
case 35:// End
if (caret < this.str.length) {
var lineEnd = this.str.indexOf('\n', caret) + 1; // If found, +1 will point to next char
if (lineEnd === 0) {
lineEnd = this.str.length;
}
result.offset = lineEnd - caret;
caret = lineEnd;
}
break;
case 36:// Home
if (caret > 0) {
var lineBegin = this.str.slice(0, caret).lastIndexOf('\n') + 1;
result.offset = lineBegin - caret;
caret = lineBegin;
}
break;
case 37:// left
if (caret > 0) {
caret = caret - 1;
result.offset = -1;
}
break;
case 39:// right
if (caret < this.str.length) {
caret = caret + 1;
result.offset = 1;
}
break;
case 8:// backspace
if (caret > 0) {
this.str = this.str.splice(caret - 1, 1);
caret = caret - 1;
this.changeCount = this.changeCount + 1;
result.offset = -1;
result.deleteCount = 1;
}
break;
case 46:// delete
if (caret < this.str.length) {
this.str = this.str.splice(caret, 1);
this.changeCount = this.changeCount + 1;
result.deleteCount = 1;
}
break;
case 45:
this.insertMode = !this.insertMode;
break;
}
}
this.cursorTable[user_id] = caret;
return result;
};
CustomBuffer.prototype.updateCursorPosition = function(data) {
this.cursorTable[data.user_id] = data.cursorPosition;
};
FileBuffer.prototype.requestBuffer = function(data) {
if ((data.appId.toString() in this.buffers) === false) {
var buf = new CustomBuffer(data);
if (data.content !== undefined && data.content !== null) {
var text = data.content.split('\r\n').join('\n');
text = this.parse(text).text;
buf.insertStr(text);
}
this.buffers[data.appId] = buf;
}
};
FileBuffer.prototype.editCredentialsForBuffer = function(data) {
if ((data.appId.toString() in this.buffers) === true) {
var buf = this.buffers[data.appId];
buf.owner = data.owner;
buf.createdOn = data.createdOn;
}
};
FileBuffer.prototype.closeFileBuffer = function(appId) {
if (this.buffers.hasOwnProperty(appId)) {
var buf = this.buffers[appId];
if (buf.changeCount > 0) {
this.writeToFile(appId);
}
delete this.buffers[appId];
delete this.files[appId];
}
};
FileBuffer.prototype.hasFileBufferForApp = function(appId) {
return (appId.toString() in this.buffers);
};
FileBuffer.prototype.associateFile = function(data) {
var fileName = data.fileName;
var fileDir = data.fileDir;
// check and create the folder if needed
if (!sageutils.folderExists(fileDir)) {
sageutils.mkdirParent(fileDir);
}
// finally, build the full path
var fullPath = path.join(fileDir, fileName);
this.files[data.appId] = fullPath;
sageutils.log("SAGE2", "File", fileName, "attached to buffer of", data.appName);
};
FileBuffer.prototype.writeToFile = function(appId) {
if (this.buffers.hasOwnProperty(appId) && this.files.hasOwnProperty(appId)) {
var buffer = this.buffers[appId];
var fileName = this.files[appId];
var bufData = buffer.getData();
/*var prefix = " _Owner:_ " + bufData.owner + " \n"
+ " _Color:_ " + bufData.color + " \n"
+ " _Created On:_ " + bufData.createdOn + " \n";
*/
var output = bufData.text.split('\n').join('\r\n');
fs.writeFile(fileName, output, function(err) {
if (err) {
return console.log(err);
}
buffer.resetChange();
});
}
};
FileBuffer.prototype.insertChar = function(data) {
if (this.buffers.hasOwnProperty(data.appId)) {
var buffer = this.buffers[data.appId];
var update = buffer.insertChar(data.code, data.printable, data.user_id);
if (buffer.changeCount > 15) {
this.writeToFile(data.appId);
}
return update;
}
};
FileBuffer.prototype.insertStr = function(data) {
if (this.buffers.hasOwnProperty(data.appId)) {
var buffer = this.buffers[data.appId];
var text = data.text.split('\r\n').join('\n');
text = this.parse(text).text;
var update = buffer.insertStr(text, data.user_id);
if (buffer.changeCount > 15) {
this.writeToFile(data.appId);
}
return update;
}
};
FileBuffer.prototype.parse = function(data) {
try {
if (typeof data !== 'string') {
data = data.toString('utf8');
}
var parsedFileData = this.mdManager.parse(data);
return parsedFileData;
} catch (e) {
console.log("Error :->", e);
}
};
FileBuffer.prototype.updateFileBufferCursorPosition = function(data) {
if (this.buffers.hasOwnProperty(data.appId)) {
var buffer = this.buffers[data.appId];
buffer.updateCursorPosition(data);
}
};
module.exports = FileBuffer;
SAGE2: src/node-filebuffer.js