package java.lang.reflect;

public class Method<T> extends AccessibleObject implements Member {
  private byte vmFlags;
  private byte parameterCount;
  private short parameterFootprint;
  private short flags;
  private short offset;
  private byte[] name;
  private byte[] spec;
  private Class<T> class_;
  private Object code;

  private Method() { }

  public boolean isAccessible() {
    return (vmFlags & Accessible) != 0;
  }

  public void setAccessible(boolean v) {
    if (v) vmFlags |= Accessible; else vmFlags &= ~Accessible;
  }

  public Class<T> getDeclaringClass() {
    return class_;
  }

  public int getModifiers() {
    return flags;
  }

  public String getName() {
    return new String(name, 0, name.length - 1, false);
  }

  private static int next(char c, String s, int start) {
    for (int i = start; i < s.length(); ++i) {
      if (s.charAt(i) == c) return i;
    }
    throw new RuntimeException();
  }

  public Class[] getParameterTypes() {
    int count = parameterCount;
    if ((flags & Modifier.STATIC) == 0) {
      -- count;
    }

    Class[] types = new Class[count];
    int index = 0;

    String spec = new String(this.spec, 1, this.spec.length - 1, false);

    for (int i = 0; i < spec.length(); ++i) {
      char c = spec.charAt(i);
      if (c == ')') {
        break;
      } else if (c == 'L') {
        int start = i + 1;
        i = next(';', spec, start);
        String name = spec.substring(start, i);
        types[index++] = Class.forName(name);
      } else if (c == '[') {
        int start = i;
        while (spec.charAt(i) == '[') ++i;

        if (spec.charAt(i) == 'L') {
          i = next(';', spec, i + 1);
          String name = spec.substring(start, i);
          types[index++] = Class.forName(name);
        } else {
          String name = spec.substring(start, i + 1);
          types[index++] = Class.forName(name);
        }
      } else {
        String name = spec.substring(i, i + 1);
        types[index++] = Class.forName(name);
      }
    }

    return types;
  }

  public native Object invoke(Object instance, Object ... arguments);
}