61 lines
1.9 KiB
JavaScript
61 lines
1.9 KiB
JavaScript
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let output = document.getElementById("output");
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let input;
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let fileContent;
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function readFile(input) {
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let file = input.files[0];
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console.log("Reading file", file)
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let fileReader = new FileReader();
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fileReader.readAsText(file);
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fileReader.onload = function() {
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fileContent = fileReader.result;
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};
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fileReader.onerror = function() {
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alert(fileReader.error);
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};
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}
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let start = document.getElementById("start");
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start.addEventListener("mouseover", () => {
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start.innerHTML = "JUST DO IT"
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});
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start.addEventListener("mouseout", () => {
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start.innerHTML = "Read File"
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});
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start.addEventListener("click", () => {
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findPosition(fileContent)
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});
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function findPosition(line) {
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let i = 4;
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let packetStart = line.substring(0, 4); // should always contain 4 chars
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let messageStart = line.substring(0, 14); // should always contain 14 chars
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let packetStartI = 0;
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while (i < line.length) {
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console.log(i, "Char", line[i], "chars:", packetStart);
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// if packetStart not found, look for packet start
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if (packetStartI == 0) {
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if (/(.).*\1/.test(packetStart)) { // if unique
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packetStart = packetStart.substring(1, 4) + line[i];
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}
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else {
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packetStartI = i;
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messageStart = line.substring(i, i + 14);
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}
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}
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else { // search for message start
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if (/(.).*\1/.test(messageStart)) { // if unique
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messageStart = messageStart.substring(1, 14) + line[i];
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}
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else {
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output.innerHTML = "Found the first packet start marker at position <b>" + packetStartI + "</b>, the marker is " + packetStart + "<br>" +
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"Found the first message start marker at position <b>" + i + "</b>, the marker is " + messageStart + "\n";
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return;
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}
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}
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i++;
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}
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}
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