// Copyright (c) 2022, the R8 project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
package com.android.tools.r8.keepanno.asm;

import com.android.tools.r8.keepanno.ast.KeepEdgeException;
import com.android.tools.r8.keepanno.ast.KeepMethodReturnTypePattern;
import com.android.tools.r8.keepanno.ast.KeepTypePattern;

/**
 * Utilities for mapping the syntax used in annotations to the keep-edge AST.
 *
 * <p>The AST explicitly avoids interpreting type strings as they are potentially ambiguous. These
 * utilities define the mappings from such syntax strings into the AST.
 */
public class KeepEdgeReaderUtils {

  public static KeepTypePattern typePatternFromString(String string) {
    if (string.equals("<any>")) {
      return KeepTypePattern.any();
    }
    return KeepTypePattern.fromDescriptor(javaTypeToDescriptor(string));
  }

  public static String javaTypeToDescriptor(String type) {
    switch (type) {
      case "boolean":
        return "Z";
      case "byte":
        return "B";
      case "short":
        return "S";
      case "int":
        return "I";
      case "long":
        return "J";
      case "float":
        return "F";
      case "double":
        return "D";
      default:
        {
          StringBuilder builder = new StringBuilder(type.length());
          int i = type.length() - 1;
          while (type.charAt(i) == ']') {
            if (type.charAt(--i) != '[') {
              throw new KeepEdgeException("Invalid type: " + type);
            }
            builder.append('[');
            --i;
          }
          builder.append('L');
          for (int j = 0; j <= i; j++) {
            char c = type.charAt(j);
            builder.append(c == '.' ? '/' : c);
          }
          builder.append(';');
          return builder.toString();
        }
    }
  }

  public static KeepMethodReturnTypePattern methodReturnTypeFromString(String returnType) {
    if ("void".equals(returnType)) {
      return KeepMethodReturnTypePattern.voidType();
    }
    return KeepMethodReturnTypePattern.fromType(typePatternFromString(returnType));
  }
}