getCompletionContext method

CompletionContext? getCompletionContext(String input, int cursorOffset)

Get the token boundaries at the cursor position for inline completion

Implementation

CompletionContext? getCompletionContext(String input, int cursorOffset) {
  if (cursorOffset == -1) {
    cursorOffset = input.length;
  }

  var result = parser.parsePrefix(input, typeChecker: typeChecker);

  if (!result.success || result.value == null) {
    return null;
  }

  final node = _findNodeAt(result.value!, cursorOffset);
  if (node == null) {
    return null;
  }

  // Determine what part of the node is being completed
  int tokenStart;
  int tokenEnd;
  String tokenType;

  if (node is MemberExpression) {
    // Completing the property name after the dot
    // e.g., "user.na|me" - we want token boundaries of "name"
    tokenStart = node.property.start;
    tokenEnd = node.property.end;
    tokenType = "property";
  }
  else if (node is Variable) {
    // Completing a variable name
    // e.g., "us|er" - we want token boundaries of "user"
    tokenStart = node.identifier.start;
    tokenEnd = node.identifier.end;
    tokenType = "variable";
  }
  else if (node is Identifier) {
    // Direct identifier completion
    tokenStart = node.start;
    tokenEnd = node.end;
    tokenType = "identifier";
  }
  else if (node is CallExpression) {
    // Check if we're on the callee (function name)
    if (cursorOffset >= node.callee.start && cursorOffset <= node.callee.end) {
      // Recursively get context for the callee
      final calleeContext = _getNodeContext(node.callee, cursorOffset);
      if (calleeContext != null) return calleeContext;
    }
    // Otherwise we're in arguments
    tokenStart = node.start;
    tokenEnd = node.end;
    tokenType = "call";
  }
  else {
    // Fallback to the node boundaries
    tokenStart = node.start;
    tokenEnd = node.end;
    tokenType = node.runtimeType.toString().toLowerCase();
  }

  return CompletionContext(
    tokenStart: tokenStart,
    tokenEnd: tokenEnd,
    tokenType: tokenType,
    node: node,
  );
}