From ff84493fac65cdcdf836400b844b42b8b2b7e1e1 Mon Sep 17 00:00:00 2001
From: "Jill \"oatmealine\" Monoids" <oatmealine@disroot.org>
Date: Wed, 3 Nov 2021 11:24:05 +0300
Subject: [PATCH] better type transpiling

---
 index.js | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 50 insertions(+), 4 deletions(-)

diff --git a/index.js b/index.js
index d39bb71..faf4467 100644
--- a/index.js
+++ b/index.js
@@ -8,6 +8,51 @@ const outPath = path.resolve(__dirname, './out/');
 
 let classes = {};
 
+let tsToLuaTypes = {
+  undefined: 'nil',
+  unknown: 'any',
+}
+
+function transpileType(type) {
+  type = type.trim();
+
+  if (type.startsWith('(') && type.endsWith(')')) type = type.slice(1, -1);
+
+  if (tsToLuaTypes[type]) {
+    return tsToLuaTypes[type];
+  }
+
+  if (type.endsWith('[]')) {
+    return transpileType(type.slice(0, -2)) + '[]';
+  }
+
+  if (type.includes('|')) {
+    return type.split('|').map(t => transpileType(t)).join(' | ');
+  }
+
+  if (type.startsWith('Record<')) {
+    return 'table<' + transpileType(type.split(',')[0].replace('Record<','')) + ', ' + transpileType(type.split(',')[1].replace('>','')) + '>';
+  }
+  if (type.startsWith('LuaTable<')) {
+    return 'table<' + transpileType(type.split(',')[0].replace('LuaTable<','')) + ', ' + transpileType(type.split(',')[1].replace('>','')) + '>';
+  }
+
+  let match;
+
+  if (match = /\((.*?)\) ?=> ?(.*)/.exec(type)) { // functions
+    return `fun(${match[1] !== '' ? match[1].split(',').map(c => c.split(':')[0] + ':' + transpileType(c.split(':')[1])).join(',') : ''}): ${transpileType(match[2])}`;
+  }
+
+  if (match = /(?:Array)|(?:Map)<(.*?)>/.exec(type)) {
+    return transpileType(match[1]) + '[]';
+  }
+
+  if (match = /(.*?)<(.*?)>/.exec(type)) { // any other weird type we just discard
+    return transpileType(match[2]);
+  }
+  return type;
+}
+
 function transpile(parsed, indent, prefix) {
   let global = false;
   indent = indent || 0;
@@ -29,11 +74,11 @@ function transpile(parsed, indent, prefix) {
       }
 
       classes[d.name] = contents;
-      return `---@class ${d.name}${n}${contents.filter(e => e[0] === 'const').map(c => `---@field public ${c[1].name} ${c[1].type}${n}`).join('')}${global ? '' : '__class_'}${d.name} = {}${n}${contents.filter(e => e[0] !== 'const').map(c => transpile(c, indent, `${global ? '' : '__class_'}${d.name}`)).join(n)}\n`;
+      return `---@class ${d.name}${n}${contents.filter(e => e[0] === 'const').map(c => `---@field public ${c[1].name} ${transpileType(c[1].type)}${n}`).join('')}${global ? '' : '__class_'}${d.name} = {}${n}${contents.filter(e => e[0] !== 'const').map(c => transpile(c, indent, `${global ? '' : '__class_'}${d.name}`)).join(n)}\n`;
     case 'function':
-      return `${d.arguments.map(p => `---@param ${p.name.replace('?', '')} ${p.type}${n}`).join('')}---@return ${d.returns}${n}function ${prefix ? prefix + ':' : ''}${d.name}(${d.arguments.map(a => a.name.replace('?', '')).join(', ')}) end`;
+      return `${d.arguments.map(p => `---@param ${p.name.replace('?', '')} ${transpileType(p.type)}${n}`).join('')}---@return ${transpileType(d.returns)}${n}function ${prefix ? prefix + ':' : ''}${d.name}(${d.arguments.map(a => a.name.replace('?', '')).join(', ')}) end`;
     case 'const':
-      return `---@type ${d.type}${n}${prefix ? prefix + '.' : ''}${d.name} = nil`;
+      return `---@type ${transpileType(d.type)}${n}${prefix ? prefix + '.' : ''}${d.name} = nil`;
     case 'enum':
       return `${prefix ? prefix + '.' : ''}${d.name} = {${n}  ${d.contents.map(c => `${c.name} = ${c.value}`).join(`,${n}  `)}${n}}`;
   }
@@ -61,6 +106,7 @@ function parse(code) {
   // sanitize stuff
   code = removeComments(code);
 
+  let match;
   const elements = [];
 
   // look for interfaces
@@ -83,7 +129,7 @@ function parse(code) {
 
   // look for functions
   let functionFreeCode = code;
-  const functions = /(function)?\s(\w+)\s*\(([^;]*)\)(\s*:\s*([\w\[\]]+))?/g; // wow this sucks
+  const functions = /(function)?\s(\w+)\s*\(([^;]*)\)(\s*:\s*([\w\[\]\s|<>,]+))?/g; // wow this sucks
   while ((match = functions.exec(code)) !== null) {
     functionFreeCode = functionFreeCode.replace(match[0], '');
     let arguments = match[3].split(',').map(s => {