/**
* TSCN Value Parser
* Handles parsing of TSCN value types (primitives, arrays, dictionaries, function calls)
* ISO/IEC 25010 compliant - Single Responsibility Principle
*/
import type { TscnValue, TscnFunctionCall } from './types.js';
/**
* Parse a value string into appropriate type
*/
export function parseValue(str: string): TscnValue {
const trimmed = str.trim();
// Null
if (trimmed === 'null') {
return null;
}
// Boolean
if (trimmed === 'true') {
return true;
}
if (trimmed === 'false') {
return false;
}
// Number
if (/^-?\d+(\.\d+)?$/.test(trimmed)) {
return parseFloat(trimmed);
}
// String
if (trimmed.startsWith('"') && trimmed.endsWith('"')) {
return trimmed.slice(1, -1);
}
// Array
if (trimmed.startsWith('[') && trimmed.endsWith(']')) {
return parseArray(trimmed);
}
// Dictionary
if (trimmed.startsWith('{') && trimmed.endsWith('}')) {
return parseDictionary(trimmed);
}
// Function call (Vector2, Color, ExtResource, SubResource, etc.)
const funcMatch = trimmed.match(/^(\w+)\s*\((.*)\)$/s);
if (funcMatch) {
return {
name: funcMatch[1],
args: parseArguments(funcMatch[2]),
};
}
// Raw string
return trimmed;
}
/**
* Parse array notation
*/
export function parseArray(str: string): TscnValue[] {
const inner = str.slice(1, -1).trim();
if (inner === '') {
return [];
}
const args = parseArguments(inner);
return args;
}
/**
* Parse dictionary notation
*/
export function parseDictionary(str: string): Record<string, TscnValue> {
const inner = str.slice(1, -1).trim();
if (inner === '') {
return {};
}
const result: Record<string, TscnValue> = {};
const pairs = splitTopLevel(inner, ',');
for (const pair of pairs) {
const colonIdx = findTopLevelChar(pair, ':');
if (colonIdx === -1) continue;
const keyStr = pair.slice(0, colonIdx).trim();
const valueStr = pair.slice(colonIdx + 1).trim();
// Parse key (remove quotes if present)
const key = keyStr.startsWith('"') && keyStr.endsWith('"')
? keyStr.slice(1, -1)
: keyStr;
result[key] = parseValue(valueStr);
}
return result;
}
/**
* Parse function arguments
*/
export function parseArguments(str: string): TscnValue[] {
const trimmed = str.trim();
if (trimmed === '') {
return [];
}
const parts = splitTopLevel(trimmed, ',');
return parts.map(part => parseValue(part.trim()));
}
/**
* Split string by delimiter at top level (not inside brackets or quotes)
*/
export function splitTopLevel(str: string, delimiter: string): string[] {
const result: string[] = [];
let current = '';
let depth = 0;
let inString = false;
let stringChar = '';
for (let i = 0; i < str.length; i++) {
const char = str[i];
if (inString) {
current += char;
if (char === stringChar && str[i - 1] !== '\\') {
inString = false;
}
} else if (char === '"' || char === "'") {
inString = true;
stringChar = char;
current += char;
} else if (char === '(' || char === '[' || char === '{') {
depth++;
current += char;
} else if (char === ')' || char === ']' || char === '}') {
depth--;
current += char;
} else if (char === delimiter && depth === 0) {
result.push(current);
current = '';
} else {
current += char;
}
}
if (current.length > 0) {
result.push(current);
}
return result;
}
/**
* Find index of character at top level
*/
export function findTopLevelChar(str: string, char: string): number {
let depth = 0;
let inString = false;
let stringChar = '';
for (let i = 0; i < str.length; i++) {
const c = str[i];
if (inString) {
if (c === stringChar && str[i - 1] !== '\\') {
inString = false;
}
} else if (c === '"' || c === "'") {
inString = true;
stringChar = c;
} else if (c === '(' || c === '[' || c === '{') {
depth++;
} else if (c === ')' || c === ']' || c === '}') {
depth--;
} else if (c === char && depth === 0) {
return i;
}
}
return -1;
}
/**
* Check if a value is a function call (type guard)
* Accepts unknown for runtime validation of external data
* ISO/IEC 5055: Defensive programming - validate before use
*/
export function isFunctionCall(value: unknown): value is TscnFunctionCall {
return (
typeof value === 'object' &&
value !== null &&
!Array.isArray(value) &&
'name' in value &&
'args' in value
);
}
