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(function() {
var preTags = document.getElementsByTagName('pre');
var preWithHeaderInfo = preTags[0];
var preWithContent = preTags[2];
var lines = preWithContent.textContent.split('\n');
// get data about the formatting (changes between different versions of chrome)
var rgx = /^(0{8}:\s+)([0-9a-f]{2}\s+)[0-9a-f]{2}/m;
var match = rgx.exec(lines[0]);
var text = '';
for (var i = 0; i < lines.length; i++) {
var line = lines[i];
var firstIndex = match[1].length; // first index of the chars to match (e.g. where a '84' would start)
var indexJump = match[2].length; // how much space is between each set of numbers
var totalCharsPerLine = 16;
index = firstIndex;
for (var j = 0; j < totalCharsPerLine; j++) {
var hexValAsStr = line.substr(index, 2);
if (hexValAsStr == ' ') {
// no more chars
break;
}
var asciiVal = parseInt(hexValAsStr, 16);
text += String.fromCharCode(asciiVal);
index += indexJump;
}
}
var headerText = preWithHeaderInfo.textContent;
var elToInsertBefore = document.body.childNodes[0];
var insertedDiv = document.createElement("div");
document.body.insertBefore(insertedDiv, elToInsertBefore);
// find the filename
var nodes = [document.body];
var filepath = '';
while (true) {
var node = nodes.pop();
if (node.hasChildNodes()) {
var children = node.childNodes;
for (var i = children.length - 1; i >= 0; i--) {
nodes.push(children[i]);
}
}
if (node.nodeType === Node.TEXT_NODE && /\S/.test(node.nodeValue)) {
// 1st depth-first text node (with non-whitespace chars) found
filepath = node.nodeValue;
break;
}
}
outputResults(insertedDiv, convertToBase64(text), filepath, headerText);
insertedDiv.appendChild(document.createElement('hr'));
function outputResults(parentElement, fileContents, fileUrl, headerText) {
// last updated 1/27/12
var rgx = /.+\/([^\/]+)/;
var filename = rgx.exec(fileUrl)[1];
// get the content type
rgx = /content-type: (.+)/i;
var match = rgx.exec(headerText);
var contentTypeFound = match != null;
var contentType = "text/plain";
if (contentTypeFound) {
contentType = match[1];
}
var dataUri = "data:" + contentType + ";base64," + fileContents;
// check for gzipped file
var gZipRgx = /content-encoding: gzip/i;
if (gZipRgx.test(headerText)) {
filename += '.gz';
}
// check for image
var imageRgx = /image/i;
var isImage = imageRgx.test(contentType);
// create link
var aTag = document.createElement('a');
aTag.textContent = "Left-click to download the cached file";
aTag.setAttribute('href', dataUri);
aTag.setAttribute('download', filename);
parentElement.appendChild(aTag);
parentElement.appendChild(document.createElement('br'));
// create image
if (isImage) {
var imgTag = document.createElement('img');
imgTag.setAttribute("src", dataUri);
parentElement.appendChild(imgTag);
parentElement.appendChild(document.createElement('br'));
}
// create warning
if (!contentTypeFound) {
var pTag = document.createElement('p');
pTag.textContent = "WARNING: the type of file was not found in the headers... defaulting to text file.";
parentElement.appendChild(pTag);
}
}
function getBase64Char(base64Value) {
if (base64Value < 0) {
throw "Invalid number: " + base64Value;
} else if (base64Value <= 25) {
// A-Z
return String.fromCharCode(base64Value + "A".charCodeAt(0));
} else if (base64Value <= 51) {
// a-z
base64Value -= 26; // a
return String.fromCharCode(base64Value + "a".charCodeAt(0));
} else if (base64Value <= 61) {
// 0-9
base64Value -= 52; // 0
return String.fromCharCode(base64Value + "0".charCodeAt(0));
} else if (base64Value <= 62) {
return '+';
} else if (base64Value <= 63) {
return '/';
} else {
throw "Invalid number: " + base64Value;
}
}
function convertToBase64(input) {
// http://en.wikipedia.org/wiki/Base64#Example
var remainingBits;
var result = "";
var additionalCharsNeeded = 0;
var charIndex = -1;
var charAsciiValue;
var advanceToNextChar = function() {
charIndex++;
charAsciiValue = input.charCodeAt(charIndex);
return charIndex < input.length;
};
while (true) {
var base64Char;
// handle 1st char
if (!advanceToNextChar()) break;
base64Char = charAsciiValue >>> 2;
remainingBits = charAsciiValue & 3; // 0000 0011
result += getBase64Char(base64Char); // 1st char
additionalCharsNeeded = 3;
// handle 2nd char
if (!advanceToNextChar()) break;
base64Char = (remainingBits << 4) | (charAsciiValue >>> 4);
remainingBits = charAsciiValue & 15; // 0000 1111
result += getBase64Char(base64Char); // 2nd char
additionalCharsNeeded = 2;
// handle 3rd char
if (!advanceToNextChar()) break;
base64Char = (remainingBits << 2) | (charAsciiValue >>> 6);
result += getBase64Char(base64Char); // 3rd char
remainingBits = charAsciiValue & 63; // 0011 1111
result += getBase64Char(remainingBits); // 4th char
additionalCharsNeeded = 0;
}
// there may be an additional 2-3 chars that need to be added
if (additionalCharsNeeded == 2) {
remainingBits = remainingBits << 2; // 4 extra bits
result += getBase64Char(remainingBits) + "=";
} else if (additionalCharsNeeded == 3) {
remainingBits = remainingBits << 4; // 2 extra bits
result += getBase64Char(remainingBits) + "==";
} else if (additionalCharsNeeded != 0) {
throw "Unhandled number of additional chars needed: " + additionalCharsNeeded;
}
return result;
}
})()
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