Commit js, ts, and definitions in separate folders

src/script_number.js

@@ -0,0 +1,60 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+function decode(buffer, maxLength, minimal) {
+    maxLength = maxLength || 4;
+    minimal = minimal === undefined ? true : minimal;
+    const length = buffer.length;
+    if (length === 0)
+        return 0;
+    if (length > maxLength)
+        throw new TypeError('Script number overflow');
+    if (minimal) {
+        if ((buffer[length - 1] & 0x7f) === 0) {
+            if (length <= 1 || (buffer[length - 2] & 0x80) === 0)
+                throw new Error('Non-minimally encoded script number');
+        }
+    }
+    // 40-bit
+    if (length === 5) {
+        const a = buffer.readUInt32LE(0);
+        const b = buffer.readUInt8(4);
+        if (b & 0x80)
+            return -(((b & ~0x80) * 0x100000000) + a);
+        return (b * 0x100000000) + a;
+    }
+    // 32-bit / 24-bit / 16-bit / 8-bit
+    let result = 0;
+    for (var i = 0; i < length; ++i) {
+        result |= buffer[i] << (8 * i);
+    }
+    if (buffer[length - 1] & 0x80)
+        return -(result & ~(0x80 << (8 * (length - 1))));
+    return result;
+}
+exports.decode = decode;
+function scriptNumSize(i) {
+    return i > 0x7fffffff ? 5
+        : i > 0x7fffff ? 4
+            : i > 0x7fff ? 3
+                : i > 0x7f ? 2
+                    : i > 0x00 ? 1
+                        : 0;
+}
+function encode(number) {
+    let value = Math.abs(number);
+    const size = scriptNumSize(value);
+    const buffer = Buffer.allocUnsafe(size);
+    const negative = number < 0;
+    for (var i = 0; i < size; ++i) {
+        buffer.writeUInt8(value & 0xff, i);
+        value >>= 8;
+    }
+    if (buffer[size - 1] & 0x80) {
+        buffer.writeUInt8(negative ? 0x80 : 0x00, size - 1);
+    }
+    else if (negative) {
+        buffer[size - 1] |= 0x80;
+    }
+    return buffer;
+}
+exports.encode = encode;