/*******************************************************************************
 * Copyright (c) 2015-2018 Skymind, Inc.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Apache License, Version 2.0 which is available at
 * https://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.
 *
 * SPDX-License-Identifier: Apache-2.0
 ******************************************************************************/

package org.nd4j.linalg.io;

import java.lang.reflect.Array;
import java.util.Arrays;

public abstract class ObjectUtils {
    private static final int INITIAL_HASH = 7;
    private static final int MULTIPLIER = 31;
    private static final String EMPTY_STRING = "";
    private static final String NULL_STRING = "null";
    private static final String ARRAY_START = "{";
    private static final String ARRAY_END = "}";
    private static final String EMPTY_ARRAY = "{}";
    private static final String ARRAY_ELEMENT_SEPARATOR = ", ";

    public ObjectUtils() {}

    public static boolean isCheckedException(Throwable ex) {
        return !(ex instanceof RuntimeException) && !(ex instanceof Error);
    }

    public static boolean isCompatibleWithThrowsClause(Throwable ex, Class[] declaredExceptions) {
        if (!isCheckedException(ex)) {
            return true;
        } else {
            if (declaredExceptions != null) {
                for (int i = 0; i < declaredExceptions.length; ++i) {
                    if (declaredExceptions[i].isAssignableFrom(ex.getClass())) {
                        return true;
                    }
                }
            }

            return false;
        }
    }

    public static boolean isArray(Object obj) {
        return obj != null && obj.getClass().isArray();
    }

    public static boolean isEmpty(Object[] array) {
        return array == null || array.length == 0;
    }

    public static boolean containsElement(Object[] array, Object element) {
        if (array == null) {
            return false;
        } else {
            Object[] arr$ = array;
            int len$ = array.length;

            for (int i$ = 0; i$ < len$; ++i$) {
                Object arrayEle = arr$[i$];
                if (nullSafeEquals(arrayEle, element)) {
                    return true;
                }
            }

            return false;
        }
    }

    public static boolean containsConstant(Enum<?>[] enumValues, String constant) {
        return containsConstant(enumValues, constant, false);
    }

    public static boolean containsConstant(Enum<?>[] enumValues, String constant, boolean caseSensitive) {
        Enum[] arr$ = enumValues;
        int len$ = enumValues.length;
        int i$ = 0;

        while (true) {
            if (i$ >= len$) {
                return false;
            }

            Enum candidate = arr$[i$];
            if (caseSensitive) {
                if (candidate.toString().equals(constant)) {
                    break;
                }
            } else if (candidate.toString().equalsIgnoreCase(constant)) {
                break;
            }

            ++i$;
        }

        return true;
    }

    public static <E extends Enum<?>> E caseInsensitiveValueOf(E[] enumValues, String constant) {
        Enum[] arr$ = enumValues;
        int len$ = enumValues.length;

        for (int i$ = 0; i$ < len$; ++i$) {
            Enum candidate = arr$[i$];
            if (candidate.toString().equalsIgnoreCase(constant)) {
                return (E) candidate;
            }
        }

        throw new IllegalArgumentException(String.format("constant [%s] does not exist in enum opType %s",
                        new Object[] {constant, enumValues.getClass().getComponentType().getName()}));
    }

    public static <A, O extends A> A[] addObjectToArray(A[] array, O obj) {
        Class compType = Object.class;
        if (array != null) {
            compType = array.getClass().getComponentType();
        } else if (obj != null) {
            compType = obj.getClass();
        }

        int newArrLength = array != null ? array.length + 1 : 1;
        Object[] newArr = (Object[]) Array.newInstance(compType, newArrLength);
        if (array != null) {
            System.arraycopy(array, 0, newArr, 0, array.length);
        }

        newArr[newArr.length - 1] = obj;
        return (A[]) newArr;
    }

    public static Object[] toObjectArray(Object source) {
        if (source instanceof Object[]) {
            return (Object[]) source;
        } else if (source == null) {
            return new Object[0];
        } else if (!source.getClass().isArray()) {
            throw new IllegalArgumentException("Source is not an array: " + source);
        } else {
            int length = Array.getLength(source);
            if (length == 0) {
                return new Object[0];
            } else {
                Class wrapperType = Array.get(source, 0).getClass();
                Object[] newArray = (Object[]) Array.newInstance(wrapperType, length);

                for (int i = 0; i < length; ++i) {
                    newArray[i] = Array.get(source, i);
                }

                return newArray;
            }
        }
    }

    public static boolean nullSafeEquals(Object o1, Object o2) {
        if (o1 == o2) {
            return true;
        } else if (o1 != null && o2 != null) {
            if (o1.equals(o2)) {
                return true;
            } else {
                if (o1.getClass().isArray() && o2.getClass().isArray()) {
                    if (o1 instanceof Object[] && o2 instanceof Object[]) {
                        return Arrays.equals((Object[]) o1, (Object[]) o2);
                    }

                    if (o1 instanceof boolean[] && o2 instanceof boolean[]) {
                        return Arrays.equals((boolean[]) o1, (boolean[]) o2);
                    }

                    if (o1 instanceof byte[] && o2 instanceof byte[]) {
                        return Arrays.equals((byte[]) o1, (byte[]) o2);
                    }

                    if (o1 instanceof char[] && o2 instanceof char[]) {
                        return Arrays.equals((char[]) o1, (char[]) o2);
                    }

                    if (o1 instanceof double[] && o2 instanceof double[]) {
                        return Arrays.equals((double[]) o1, (double[]) o2);
                    }

                    if (o1 instanceof float[] && o2 instanceof float[]) {
                        return Arrays.equals((float[]) o1, (float[]) o2);
                    }

                    if (o1 instanceof int[] && o2 instanceof int[]) {
                        return Arrays.equals((int[]) o1, (int[]) o2);
                    }

                    if (o1 instanceof long[] && o2 instanceof long[]) {
                        return Arrays.equals((long[]) o1, (long[]) o2);
                    }

                    if (o1 instanceof short[] && o2 instanceof short[]) {
                        return Arrays.equals((short[]) o1, (short[]) o2);
                    }
                }

                return false;
            }
        } else {
            return false;
        }
    }

    public static int nullSafeHashCode(Object obj) {
        if (obj == null) {
            return 0;
        } else {
            if (obj.getClass().isArray()) {
                if (obj instanceof Object[]) {
                    return nullSafeHashCode((Object[]) obj);
                }

                if (obj instanceof boolean[]) {
                    return nullSafeHashCode((boolean[]) obj);
                }

                if (obj instanceof byte[]) {
                    return nullSafeHashCode((byte[]) obj);
                }

                if (obj instanceof char[]) {
                    return nullSafeHashCode((char[]) obj);
                }

                if (obj instanceof double[]) {
                    return nullSafeHashCode((double[]) obj);
                }

                if (obj instanceof float[]) {
                    return nullSafeHashCode((float[]) obj);
                }

                if (obj instanceof int[]) {
                    return nullSafeHashCode((int[]) obj);
                }

                if (obj instanceof long[]) {
                    return nullSafeHashCode((long[]) obj);
                }

                if (obj instanceof short[]) {
                    return nullSafeHashCode((short[]) obj);
                }
            }

            return obj.hashCode();
        }
    }

    public static int nullSafeHashCode(Object[] array) {
        if (array == null) {
            return 0;
        } else {
            int hash = 7;
            int arraySize = array.length;

            for (int i = 0; i < arraySize; ++i) {
                hash = 31 * hash + nullSafeHashCode(array[i]);
            }

            return hash;
        }
    }

    public static int nullSafeHashCode(boolean[] array) {
        if (array == null) {
            return 0;
        } else {
            int hash = 7;
            int arraySize = array.length;

            for (int i = 0; i < arraySize; ++i) {
                hash = 31 * hash + hashCode(array[i]);
            }

            return hash;
        }
    }

    public static int nullSafeHashCode(byte[] array) {
        if (array == null) {
            return 0;
        } else {
            int hash = 7;
            int arraySize = array.length;

            for (int i = 0; i < arraySize; ++i) {
                hash = 31 * hash + array[i];
            }

            return hash;
        }
    }

    public static int nullSafeHashCode(char[] array) {
        if (array == null) {
            return 0;
        } else {
            int hash = 7;
            int arraySize = array.length;

            for (int i = 0; i < arraySize; ++i) {
                hash = 31 * hash + array[i];
            }

            return hash;
        }
    }

    public static int nullSafeHashCode(double[] array) {
        if (array == null) {
            return 0;
        } else {
            int hash = 7;
            int arraySize = array.length;

            for (int i = 0; i < arraySize; ++i) {
                hash = 31 * hash + hashCode(array[i]);
            }

            return hash;
        }
    }

    public static int nullSafeHashCode(float[] array) {
        if (array == null) {
            return 0;
        } else {
            int hash = 7;
            int arraySize = array.length;

            for (int i = 0; i < arraySize; ++i) {
                hash = 31 * hash + hashCode(array[i]);
            }

            return hash;
        }
    }

    public static int nullSafeHashCode(int[] array) {
        if (array == null) {
            return 0;
        } else {
            int hash = 7;
            int arraySize = array.length;

            for (int i = 0; i < arraySize; ++i) {
                hash = 31 * hash + array[i];
            }

            return hash;
        }
    }

    public static int nullSafeHashCode(long[] array) {
        if (array == null) {
            return 0;
        } else {
            int hash = 7;
            int arraySize = array.length;

            for (int i = 0; i < arraySize; ++i) {
                hash = 31 * hash + hashCode(array[i]);
            }

            return hash;
        }
    }

    public static int nullSafeHashCode(short[] array) {
        if (array == null) {
            return 0;
        } else {
            int hash = 7;
            int arraySize = array.length;

            for (int i = 0; i < arraySize; ++i) {
                hash = 31 * hash + array[i];
            }

            return hash;
        }
    }

    public static int hashCode(boolean bool) {
        return bool ? 1231 : 1237;
    }

    public static int hashCode(double dbl) {
        long bits = Double.doubleToLongBits(dbl);
        return hashCode(bits);
    }

    public static int hashCode(float flt) {
        return Float.floatToIntBits(flt);
    }

    public static int hashCode(long lng) {
        return (int) (lng ^ lng >>> 32);
    }

    public static String identityToString(Object obj) {
        return obj == null ? "" : obj.getClass().getName() + "@" + getIdentityHexString(obj);
    }

    public static String getIdentityHexString(Object obj) {
        return Integer.toHexString(System.identityHashCode(obj));
    }

    public static String getDisplayString(Object obj) {
        return obj == null ? "" : nullSafeToString(obj);
    }

    public static String nullSafeClassName(Object obj) {
        return obj != null ? obj.getClass().getName() : "null";
    }

    public static String nullSafeToString(Object obj) {
        if (obj == null) {
            return "null";
        } else if (obj instanceof String) {
            return (String) obj;
        } else if (obj instanceof Object[]) {
            return nullSafeToString((Object[]) obj);
        } else if (obj instanceof boolean[]) {
            return nullSafeToString((boolean[]) obj);
        } else if (obj instanceof byte[]) {
            return nullSafeToString((byte[]) obj);
        } else if (obj instanceof char[]) {
            return nullSafeToString((char[]) obj);
        } else if (obj instanceof double[]) {
            return nullSafeToString((double[]) obj);
        } else if (obj instanceof float[]) {
            return nullSafeToString((float[]) obj);
        } else if (obj instanceof int[]) {
            return nullSafeToString((int[]) obj);
        } else if (obj instanceof long[]) {
            return nullSafeToString((long[]) obj);
        } else if (obj instanceof short[]) {
            return nullSafeToString((short[]) obj);
        } else {
            String str = obj.toString();
            return str != null ? str : "";
        }
    }

    public static String nullSafeToString(Object[] array) {
        if (array == null) {
            return "null";
        } else {
            int length = array.length;
            if (length == 0) {
                return "{}";
            } else {
                StringBuilder sb = new StringBuilder();

                for (int i = 0; i < length; ++i) {
                    if (i == 0) {
                        sb.append("{");
                    } else {
                        sb.append(", ");
                    }

                    sb.append(String.valueOf(array[i]));
                }

                sb.append("}");
                return sb.toString();
            }
        }
    }

    public static String nullSafeToString(boolean[] array) {
        if (array == null) {
            return "null";
        } else {
            int length = array.length;
            if (length == 0) {
                return "{}";
            } else {
                StringBuilder sb = new StringBuilder();

                for (int i = 0; i < length; ++i) {
                    if (i == 0) {
                        sb.append("{");
                    } else {
                        sb.append(", ");
                    }

                    sb.append(array[i]);
                }

                sb.append("}");
                return sb.toString();
            }
        }
    }

    public static String nullSafeToString(byte[] array) {
        if (array == null) {
            return "null";
        } else {
            int length = array.length;
            if (length == 0) {
                return "{}";
            } else {
                StringBuilder sb = new StringBuilder();

                for (int i = 0; i < length; ++i) {
                    if (i == 0) {
                        sb.append("{");
                    } else {
                        sb.append(", ");
                    }

                    sb.append(array[i]);
                }

                sb.append("}");
                return sb.toString();
            }
        }
    }

    public static String nullSafeToString(char[] array) {
        if (array == null) {
            return "null";
        } else {
            int length = array.length;
            if (length == 0) {
                return "{}";
            } else {
                StringBuilder sb = new StringBuilder();

                for (int i = 0; i < length; ++i) {
                    if (i == 0) {
                        sb.append("{");
                    } else {
                        sb.append(", ");
                    }

                    sb.append("\'").append(array[i]).append("\'");
                }

                sb.append("}");
                return sb.toString();
            }
        }
    }

    public static String nullSafeToString(double[] array) {
        if (array == null) {
            return "null";
        } else {
            int length = array.length;
            if (length == 0) {
                return "{}";
            } else {
                StringBuilder sb = new StringBuilder();

                for (int i = 0; i < length; ++i) {
                    if (i == 0) {
                        sb.append("{");
                    } else {
                        sb.append(", ");
                    }

                    sb.append(array[i]);
                }

                sb.append("}");
                return sb.toString();
            }
        }
    }

    public static String nullSafeToString(float[] array) {
        if (array == null) {
            return "null";
        } else {
            int length = array.length;
            if (length == 0) {
                return "{}";
            } else {
                StringBuilder sb = new StringBuilder();

                for (int i = 0; i < length; ++i) {
                    if (i == 0) {
                        sb.append("{");
                    } else {
                        sb.append(", ");
                    }

                    sb.append(array[i]);
                }

                sb.append("}");
                return sb.toString();
            }
        }
    }

    public static String nullSafeToString(int[] array) {
        if (array == null) {
            return "null";
        } else {
            int length = array.length;
            if (length == 0) {
                return "{}";
            } else {
                StringBuilder sb = new StringBuilder();

                for (int i = 0; i < length; ++i) {
                    if (i == 0) {
                        sb.append("{");
                    } else {
                        sb.append(", ");
                    }

                    sb.append(array[i]);
                }

                sb.append("}");
                return sb.toString();
            }
        }
    }

    public static String nullSafeToString(long[] array) {
        if (array == null) {
            return "null";
        } else {
            int length = array.length;
            if (length == 0) {
                return "{}";
            } else {
                StringBuilder sb = new StringBuilder();

                for (int i = 0; i < length; ++i) {
                    if (i == 0) {
                        sb.append("{");
                    } else {
                        sb.append(", ");
                    }

                    sb.append(array[i]);
                }

                sb.append("}");
                return sb.toString();
            }
        }
    }

    public static String nullSafeToString(short[] array) {
        if (array == null) {
            return "null";
        } else {
            int length = array.length;
            if (length == 0) {
                return "{}";
            } else {
                StringBuilder sb = new StringBuilder();

                for (int i = 0; i < length; ++i) {
                    if (i == 0) {
                        sb.append("{");
                    } else {
                        sb.append(", ");
                    }

                    sb.append(array[i]);
                }

                sb.append("}");
                return sb.toString();
            }
        }
    }
}
