/*-
 * ============LICENSE_START=======================================================
 * SDC
 * ================================================================================
 * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
 * ================================================================================
 * 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.
 * ============LICENSE_END=========================================================
 */
package org.openecomp.sdc.be.model.tosca.validators;

import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
import com.google.gson.JsonPrimitive;
import com.google.gson.JsonSyntaxException;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import org.apache.commons.lang3.tuple.ImmutablePair;
import org.openecomp.sdc.be.model.DataTypeDefinition;
import org.openecomp.sdc.be.model.PropertyDefinition;
import org.openecomp.sdc.be.model.tosca.ToscaPropertyType;
import org.openecomp.sdc.be.model.tosca.converters.PropertyValueConverter;
import org.openecomp.sdc.common.log.wrappers.Logger;

public class DataTypeValidatorConverter {

    private static final Logger log = Logger.getLogger(DataTypeValidatorConverter.class.getName());
    private static DataTypeValidatorConverter dataTypeValidatorConverter = new DataTypeValidatorConverter();
    JsonParser jsonParser = new JsonParser();
    ImmutablePair<JsonElement, Boolean> falseResult = new ImmutablePair<>(null, false);
    ImmutablePair<JsonElement, Boolean> trueEmptyResult = new ImmutablePair<>(null, true);
    ImmutablePair<String, Boolean> trueStringEmptyResult = new ImmutablePair<>(null, true);
    ImmutablePair<String, Boolean> falseStringEmptyResult = new ImmutablePair<>(null, true);

    private DataTypeValidatorConverter() {
    }

    public static DataTypeValidatorConverter getInstance() {
        return dataTypeValidatorConverter;
    }

    private ToscaPropertyType isDataTypeDerviedFromScalarType(DataTypeDefinition dataTypeDef) {
        ToscaPropertyType result = null;
        DataTypeDefinition dataType = dataTypeDef;
        while (dataType != null) {
            String name = dataType.getName();
            ToscaPropertyType typeIfScalar = ToscaPropertyType.getTypeIfScalar(name);
            if (typeIfScalar != null) {
                result = typeIfScalar;
                break;
            }
            dataType = dataType.getDerivedFrom();
        }
        return result;
    }

    private ImmutablePair<JsonElement, Boolean> validateAndUpdate(JsonElement jsonElement, DataTypeDefinition dataTypeDefinition,
                                                                  Map<String, DataTypeDefinition> allDataTypes) {
        Map<String, PropertyDefinition> allProperties = getAllProperties(dataTypeDefinition);
        ToscaPropertyType toscaPropertyType = null;
        if ((toscaPropertyType = isDataTypeDerviedFromScalarType(dataTypeDefinition)) != null) {
            PropertyTypeValidator validator = toscaPropertyType.getValidator();
            PropertyValueConverter converter = toscaPropertyType.getConverter();
            if (jsonElement == null || jsonElement.isJsonNull()) {
                boolean valid = validator.isValid(null, null, allDataTypes);
                if (!valid) {
                    log.trace("Failed in validation of property {} from type {}", dataTypeDefinition.getName(), dataTypeDefinition.getName());
                    return falseResult;
                }
                return new ImmutablePair<>(jsonElement, true);
            } else {
                if (jsonElement.isJsonPrimitive()) {
                    String value = null;
                    if (jsonElement != null) {
                        if (jsonElement.toString().isEmpty()) {
                            value = "";
                        } else {
                            value = jsonElement.toString();
                        }
                    }
                    boolean valid = validator.isValid(value, null, null);
                    if (!valid) {
                        log.trace("Failed in validation of property {} from type {}. Json primitive value is {}", dataTypeDefinition.getName(),
                            dataTypeDefinition.getName(), value);
                        return falseResult;
                    }
                    String convertedValue = converter.convert(value, null, allDataTypes);
                    JsonElement element = null;
                    try {
                        element = jsonParser.parse(convertedValue);
                    } catch (JsonSyntaxException e) {
                        log.debug("Failed to parse value {} of property {} {}", convertedValue, dataTypeDefinition.getName(), e);
                        return falseResult;
                    }
                    return new ImmutablePair<>(element, true);
                } else {
                    // MAP, LIST, OTHER types cannot be applied data type

                    // definition scalar type. We currently cannot derived from

                    // map/list. (cannot add the entry schema to it)
                    log.debug("We cannot derive from list/map. Thus, the value cannot be not primitive since the data type {} is scalar one",
                        dataTypeDefinition.getName());
                    return falseResult;
                }
            }
        } else {
            if (jsonElement == null || jsonElement.isJsonNull()) {
                return new ImmutablePair<>(jsonElement, true);
            } else {
                if (jsonElement.isJsonObject()) {
                    JsonObject buildJsonObject = new JsonObject();
                    JsonObject asJsonObject = jsonElement.getAsJsonObject();
                    Set<Entry<String, JsonElement>> entrySet = asJsonObject.entrySet();
                    for (Entry<String, JsonElement> entry : entrySet) {
                        String propName = entry.getKey();
                        JsonElement elementValue = entry.getValue();
                        PropertyDefinition propertyDefinition = allProperties.get(propName);
                        if (propertyDefinition == null) {
                            log.debug("The property {} was not found under data type {}", propName, dataTypeDefinition.getName());
                            return falseResult;
                        }
                        String type = propertyDefinition.getType();
                        boolean isScalarType = ToscaPropertyType.isScalarType(type);
                        if (isScalarType) {
                            ToscaPropertyType propertyType = ToscaPropertyType.isValidType(type);
                            if (propertyType == null) {
                                log.debug("cannot find the {} under default tosca property types", type);
                                return falseResult;
                            }
                            PropertyTypeValidator validator = propertyType.getValidator();
                            String innerType = null;
                            if (propertyType == ToscaPropertyType.LIST || propertyType == ToscaPropertyType.MAP) {
                                if (propertyDefinition.getSchema() != null && propertyDefinition.getSchema().getProperty() != null) {
                                    innerType = propertyDefinition.getSchema().getProperty().getType();
                                    if (innerType == null) {
                                        log.debug("Property type {} must have inner type in its declaration.", propertyType);
                                        return falseResult;
                                    }
                                }
                            }
                            String value = null;
                            if (elementValue != null) {
                                if (elementValue.isJsonPrimitive() && elementValue.getAsString().isEmpty()) {
                                    value = "";
                                } else {
                                    value = elementValue.toString();
                                }
                            }
                            boolean isValid = validator.isValid(value, innerType, allDataTypes);
                            if (!isValid) {
                                log.debug("Failed to validate the value {} from type {}", value, propertyType);
                                return falseResult;
                            }
                            PropertyValueConverter converter = propertyType.getConverter();
                            String convertedValue = converter.convert(value, innerType, allDataTypes);
                            JsonElement element = null;
                            if (convertedValue != null) {
                                if (convertedValue.isEmpty()) {
                                    element = new JsonPrimitive("");
                                } else {
                                    try {
                                        element = jsonParser.parse(convertedValue);
                                    } catch (JsonSyntaxException e) {
                                        log.debug("Failed to parse value {} of type {}", convertedValue, propertyType, e);
                                        return falseResult;
                                    }
                                }
                            }
                            buildJsonObject.add(propName, element);
                        } else {
                            DataTypeDefinition typeDefinition = allDataTypes.get(type);
                            if (typeDefinition == null) {
                                log.debug("The data type {} cannot be found in the given data type list.", type);
                                return falseResult;
                            }
                            ImmutablePair<JsonElement, Boolean> isValid = validateAndUpdate(elementValue, typeDefinition, allDataTypes);
                            if (!isValid.getRight().booleanValue()) {
                                log.debug("Failed in validation of value {} from type {}", (elementValue != null ? elementValue.toString() : null),
                                    typeDefinition.getName());
                                return falseResult;
                            }
                            buildJsonObject.add(propName, isValid.getLeft());
                        }
                    }
                    return new ImmutablePair<>(buildJsonObject, true);
                } else {
                    log.debug("The value {} of type {} should be json object", (jsonElement != null ? jsonElement.toString() : null),
                        dataTypeDefinition.getName());
                    return falseResult;
                }
            }
        }
    }

    public ImmutablePair<JsonElement, Boolean> validateAndUpdate(String value, DataTypeDefinition dataTypeDefinition,
                                                                 Map<String, DataTypeDefinition> allDataTypes) {
        if (value == null || value.isEmpty()) {
            return trueEmptyResult;
        }
        final JsonElement jsonElement;
        try {
            jsonElement = JsonParser.parseString(value);
        } catch (JsonSyntaxException e) {
            return falseResult;
        }
        return validateAndUpdate(jsonElement, dataTypeDefinition, allDataTypes);
    }

    private Map<String, PropertyDefinition> getAllProperties(DataTypeDefinition dataTypeDefinition) {
        Map<String, PropertyDefinition> allParentsProps = new HashMap<>();
        while (dataTypeDefinition != null) {
            List<PropertyDefinition> currentParentsProps = dataTypeDefinition.getProperties();
            if (currentParentsProps != null) {
                currentParentsProps.stream().forEach(p -> allParentsProps.put(p.getName(), p));
            }
            dataTypeDefinition = dataTypeDefinition.getDerivedFrom();
        }
        return allParentsProps;
    }

    public boolean isValid(String value, DataTypeDefinition dataTypeDefinition, Map<String, DataTypeDefinition> allDataTypes) {
        if (value == null || value.isEmpty()) {
            return true;
        }
        JsonElement jsonElement = null;
        try {
            jsonElement = jsonParser.parse(value);
        } catch (JsonSyntaxException e) {
            log.debug("Failed to parse the value {} from type {}", value, dataTypeDefinition, e);
            return false;
        }
        return isValid(jsonElement, dataTypeDefinition, allDataTypes);
    }

    private boolean isValid(JsonElement jsonElement, DataTypeDefinition dataTypeDefinition, Map<String, DataTypeDefinition> allDataTypes) {
        Map<String, PropertyDefinition> allProperties = getAllProperties(dataTypeDefinition);
        ToscaPropertyType toscaPropertyType = null;
        if ((toscaPropertyType = isDataTypeDerviedFromScalarType(dataTypeDefinition)) != null) {
            PropertyTypeValidator validator = toscaPropertyType.getValidator();
            if (jsonElement == null || jsonElement.isJsonNull()) {
                boolean valid = validator.isValid(null, null, allDataTypes);
                if (!valid) {
                    log.trace("Failed in validation of property {} from type {}", dataTypeDefinition.getName(), dataTypeDefinition.getName());
                    return false;
                }
                return true;
            } else {
                if (jsonElement.isJsonPrimitive()) {
                    String value = null;
                    if (jsonElement != null) {
                        if (jsonElement.toString().isEmpty()) {
                            value = "";
                        } else {
                            value = jsonElement.toString();
                        }
                    }
                    boolean valid = validator.isValid(value, null, allDataTypes);
                    if (!valid) {
                        log.trace("Failed in validation of property {} from type {}. Json primitive value is {}", dataTypeDefinition.getName(),
                            dataTypeDefinition.getName(), value);
                        return false;
                    }
                    return true;
                } else {
                    // MAP, LIST, OTHER types cannot be applied data type

                    // definition scalar type. We currently cannot derived from

                    // map/list. (cannot add the entry schema to it)
                    log.debug("We cannot derive from list/map. Thus, the value cannot be not primitive since the data type {} is scalar one",
                        dataTypeDefinition.getName());
                    return false;
                }
            }
        } else {
            if (jsonElement == null || jsonElement.isJsonNull()) {
                return true;
            } else {
                if (jsonElement.isJsonObject()) {
                    JsonObject asJsonObject = jsonElement.getAsJsonObject();
                    Set<Entry<String, JsonElement>> entrySet = asJsonObject.entrySet();
                    for (Entry<String, JsonElement> entry : entrySet) {
                        String propName = entry.getKey();
                        JsonElement elementValue = entry.getValue();
                        PropertyDefinition propertyDefinition = allProperties.get(propName);
                        if (propertyDefinition == null) {
                            log.debug("The property {} was not found under data type {}", propName, dataTypeDefinition.getName());
                            return false;
                        }
                        String type = propertyDefinition.getType();
                        boolean isScalarType = ToscaPropertyType.isScalarType(type);
                        if (isScalarType) {
                            ToscaPropertyType propertyType = ToscaPropertyType.isValidType(type);
                            if (propertyType == null) {
                                log.debug("cannot find the {} under default tosca property types", type);
                                return false;
                            }
                            PropertyTypeValidator validator = propertyType.getValidator();
                            String innerType = null;
                            if (propertyType == ToscaPropertyType.LIST || propertyType == ToscaPropertyType.MAP) {
                                if (propertyDefinition.getSchema() != null && propertyDefinition.getSchema().getProperty() != null) {
                                    innerType = propertyDefinition.getSchema().getProperty().getType();
                                    if (innerType == null) {
                                        log.debug("Property type {} must have inner type in its declaration.", propertyType);
                                        return false;
                                    }
                                }
                            }
                            String value = null;
                            if (elementValue != null) {
                                if (elementValue.isJsonPrimitive() && elementValue.getAsString().isEmpty()) {
                                    value = "";
                                } else {
                                    value = elementValue.toString();
                                }
                            }
                            boolean isValid = validator.isValid(value, innerType, allDataTypes);
                            if (!isValid) {
                                log.debug("Failed to validate the value {} from type {}", value, propertyType);
                                return false;
                            }
                        } else {
                            DataTypeDefinition typeDefinition = allDataTypes.get(type);
                            if (typeDefinition == null) {
                                log.debug("The data type {} cannot be found in the given data type list.", type);
                                return false;
                            }
                            boolean isValid = isValid(elementValue, typeDefinition, allDataTypes);
                            if (!isValid) {
                                log.debug("Failed in validation of value {} from type {}", (elementValue != null ? elementValue.toString() : null),
                                    typeDefinition.getName());
                                return false;
                            }
                        }
                    }
                    return true;
                } else {
                    log.debug("The value {} of type {} should be json object", (jsonElement != null ? jsonElement.toString() : null),
                        dataTypeDefinition.getName());
                    return false;
                }
            }
        }
    }
}