1 files changed, 126 insertions, 0 deletions
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),
+		}));
+	});
+};