/*
 * Copyright (C) 2010 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package org.json;

class JSON {
  /**
   * Returns the input if it is a JSON-permissible value; throws otherwise.
   */
  static double checkDouble(double d) throws JSONException {
    if (Double.isInfinite(d) || Double.isNaN(d)) {
      throw new JSONException("Forbidden numeric value: " + d);
    }
    return d;
  }

  static Boolean toBoolean(Object value) {
    if (value instanceof Boolean) {
      return (Boolean) value;
    } else if (value instanceof String) {
      String stringValue = (String) value;
      if ("true".equalsIgnoreCase(stringValue)) {
        return true;
      } else if ("false".equalsIgnoreCase(stringValue)) {
        return false;
      }
    }
    return null;
  }

  static Double toDouble(Object value) {
    if (value instanceof Double) {
      return (Double) value;
    } else if (value instanceof Number) {
      return ((Number) value).doubleValue();
    } else if (value instanceof String) {
      try {
        return Double.valueOf((String) value);
      } catch (NumberFormatException ignored) {
      }
    }
    return null;
  }

  static Integer toInteger(Object value) {
    if (value instanceof Integer) {
      return (Integer) value;
    } else if (value instanceof Number) {
      return ((Number) value).intValue();
    } else if (value instanceof String) {
      try {
        return (int) Double.parseDouble((String) value);
      } catch (NumberFormatException ignored) {
      }
    }
    return null;
  }

  static Long toLong(Object value) {
    if (value instanceof Long) {
      return (Long) value;
    } else if (value instanceof Number) {
      return ((Number) value).longValue();
    } else if (value instanceof String) {
      try {
        return (long) Double.parseDouble((String) value);
      } catch (NumberFormatException ignored) {
      }
    }
    return null;
  }

  static String toString(Object value) {
    if (value instanceof String) {
      return (String) value;
    } else if (value != null) {
      return String.valueOf(value);
    }
    return null;
  }

  public static JSONException typeMismatch(Object indexOrName, Object actual, String requiredType)
      throws JSONException {
    if (actual == null) {
      throw new JSONException("Value at " + indexOrName + " is null.");
    } else {
      throw new JSONException("Value " + actual + " at " + indexOrName + " of type "
          + actual.getClass().getName() + " cannot be converted to " + requiredType);
    }
  }

  public static JSONException typeMismatch(Object actual, String requiredType)
      throws JSONException {
    if (actual == null) {
      throw new JSONException("Value is null.");
    } else {
      throw new JSONException("Value " + actual + " of type " + actual.getClass().getName()
          + " cannot be converted to " + requiredType);
    }
  }
}
