3 files changed, 219 insertions, 0 deletions
diff --git a/modules/unicode/.gitignore b/modules/unicode/.gitignore
new file mode 100644
index 0000000..0487319
--- /dev/null
+++ b/modules/unicode/.gitignore
@@ -0,0 +1 @@
+UnicodeData.txt
diff --git a/modules/unicode/index.html b/modules/unicode/index.html
new file mode 100644
index 0000000..e44a96e
--- /dev/null
+++ b/modules/unicode/index.html
@@ -0,0 +1,92 @@
+<!doctype html>
+<html>
+<head>
+<meta charset="utf-8">
+<title>Unicode character lookup</title>
+<style>
+body {
+	font-family: sans-serif;
+}
+.table > div:nth-child(odd) {
+	background-color: #eee;
+}
+.table {
+	max-height: 300px;
+	overflow-y: scroll;
+}
+</style>
+<script>
+function do_lookup() {
+	var xhr = new XMLHttpRequest();
+	xhr.onreadystatechange = function() {
+		if (xhr.readyState == 4) {
+			if (xhr.status == 200) {
+				handleResponse(JSON.parse(xhr.responseText));
+			} else {
+				alert("Request failed: " + xhr.responseText);
+			}
+		}
+	};
+	xhr.open("GET", "/unicode/lookup/" + encodeURIComponent(document.getElementById("input").value));
+	xhr.responseType = "text";
+	xhr.setRequestHeader("Content-Type", "text/plain");
+	xhr.send();
+}
+
+function handleResponse(json) {
+	console.log(json);
+
+	var elem;
+
+	/* elem = document.getElementById("json");
+	elem.innerHTML = "";
+	elem.appendChild(document.createTextNode(JSON.stringify(json))); */
+
+	var keys = ["chars", "search"];
+
+	for (var i = 0; i < keys.length; i++) {
+		document.getElementById(keys[i] + "_num").innerHTML = "(" + json[keys[i]].length + ")";
+
+		elem = document.getElementById(keys[i]);
+		elem.innerHTML = "";
+		for (var j = 0; j < json[keys[i]].length; j++) {
+			var div = document.createElement("div");
+			div.classList.add("character");
+			populateCharacter(div, json[keys[i]][j]);
+			elem.appendChild(div);
+		}
+	}
+}
+
+function populateCharacter(div, row) {
+	var span = document.createElement("span");
+	span.setAttribute("style", "display: inline-block; width: 7em; font-weight: bold;");
+	span.appendChild(document.createTextNode("U+" + row[0]));
+	div.appendChild(span);
+
+	span = document.createElement("span");
+	span.appendChild(document.createTextNode(row[1]));
+	div.appendChild(span);
+}
+
+window.addEventListener("load", function() {
+	document.getElementById("input").focus();
+});
+</script>
+</head>
+<body>
+	<h1>Unicode character lookup</h1>
+
+	<input type="text" id="input" placeholder="Character(s) to look up" onkeypress="if (event.keyCode == 10 || event.keyCode == 13) do_lookup()">
+	<input type="button" onclick="do_lookup()" value="Lookup">
+	<br>
+
+	<!-- <pre id="json"></pre><br> -->
+
+	<h3>Characters <span id="chars_num"></span></h3>
+	<div id="chars" class="table"></div>
+
+	<h3>Found in descriptions <span id="search_num"></span></h3>
+	<div id="search" class="table"></div>
+</body>
+</html>
diff --git a/modules/unicode/unicode.js b/modules/unicode/unicode.js
new file mode 100644
index 0000000..3221cb9
--- /dev/null
+++ b/modules/unicode/unicode.js
@@ -0,0 +1,126 @@
+"use strict";
+
+const cmn = require("../$common.js");
+const fs = require("fs");
+const path = require("path");
+const https = require("https");
+
+
+const fCODE      = 0;
+const fNAME      = 1;
+const fCATEGORY  = 2;
+// combining class, bidirectional category, decomposition mapping
+const fDECDIGIT  = 6;
+const fDIGIT     = 7;
+const fNUMERIC   = 8;
+const fMIRRORED  = 9;
+const fOLDNAME   = 10;
+const fCOMMENT   = 11;
+const fUPPERCASE = 12;
+const fLOWERCASE = 13;
+const fTITLECASE = 14;
+
+// db: Map(int => [Field])  (NAME is in uppercase)
+let db = new Map();
+// ranges: [{name: String, first: int, last: int}]
+let ranges = [];
+
+function importDatabase(csv) {
+	// clear the database if necessary
+	db = new Map();
+	ranges = [];
+
+	let currentRange = null;
+
+	let cursor = 0, endidx;
+	while ((endidx = csv.indexOf("\n", cursor)) != -1) {
+		const row = csv.slice(cursor, endidx).split(";");
+		cursor = endidx + 1;
+
+		const code = parseInt(row[fCODE], 16);
+
+		const m = row[fNAME].match(/^<(.*), (First|Last)>$/)
+		if (m != null) {
+			if (m[2] == "First") {
+				row[fNAME] = "<" + m[1] + ">";
+				currentRange = {name: m[1], first: code, last: null, row: row};
+			} else if (currentRange != null && m[1] == currentRange.name) {
+				currentRange.last = code;
+				ranges.push(currentRange);
+				currentRange = null;
+			}
+		} else {
+			row[fNAME] = row[fNAME].toUpperCase();
+			db.set(code, row);
+		}
+	}
+}
+
+function lookupCode(codepoint) {
+	for (const range of ranges) {
+		if (range.first <= codepoint && codepoint <= range.last) {
+			const row = range.row.slice();
+			row[fCODE] = codepoint.toString(16).toUpperCase();
+			return row;
+		}
+	}
+
+	return db.get(codepoint);
+}
+
+function searchDescription(text) {
+	text = text.toUpperCase();
+
+	const result = [];
+	for (const row of db.values()) {
+		if (row[fNAME].includes(text)) {
+			result.push(row);
+		}
+	}
+
+	return result;
+}
+
+module.exports = function (app, io, moddir) {
+	const dataFilePath = path.join(moddir, "UnicodeData.txt");
+	if (fs.existsSync(dataFilePath)) {
+		importDatabase(fs.readFileSync(dataFilePath).toString());
+	} else {
+		console.log("Downloading UnicodeData.txt...");
+
+		https.get("https://www.unicode.org/Public/13.0.0/ucd/UnicodeData-13.0.0d6.txt", res => {
+			if (res.statusCode != 200) {
+				console.log(`Could not download UnicodeData.txt: status code ${res.statusCode}`);
+				return;
+			}
+
+			res.setEncoding("utf8");
+			let buffer = "";
+			res.on("data", data => buffer += data);
+			res.on("end", () => {
+				fs.writeFileSync(dataFilePath, buffer);
+				console.log("Downloaded UnicodeData.txt");
+				importDatabase(buffer);
+			});
+		}).on("error", err => {
+			console.log("Error downloading UnicodeData.txt:", err);
+		});
+	}
+
+	app.get("/unicode", (req, res) => {
+		res.sendFile(path.join(moddir, "index.html"));
+	});
+
+	app.get("/unicode/lookup/:query", (req, res) => {
+		const chars = [];
+		for (let codepoint of req.params.query) {
+			codepoint = codepoint.codePointAt(0);
+			chars.push(lookupCode(codepoint));
+		}
+
+		res.end(JSON.stringify({
+			chars: chars,
+			search: searchDescription(req.params.query),
+		}));
+	});
+};