/*
 * Copyright 2002-2014 the original author or authors.
 *
 * 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.springframework.expression.spel;

import java.text.MessageFormat;

/**
 * Contains all the messages that can be produced by the Spring Expression Language.
 * Each message has a kind (info, warn, error) and a code number. Tests can be written to
 * expect particular code numbers rather than particular text, enabling the message text
 * to more easily be modified and the tests to run successfully in different locales.
 *
 * <p>When a message is formatted, it will have this kind of form
 *
 * <pre class="code">
 * EL1004E: (pos 34): Type cannot be found 'String'
 * </pre>
 *
 * The prefix captures the code and the error kind, whilst the position is included
 * if it is known.
 *
 * @author Andy Clement
 * @since 3.0
 */
public enum SpelMessage {

	TYPE_CONVERSION_ERROR(Kind.ERROR, 1001,
			"Type conversion problem, cannot convert from {0} to {1}"),

	CONSTRUCTOR_NOT_FOUND(Kind.ERROR, 1002,
			"Constructor call: No suitable constructor found on type {0} for arguments {1}"),

	CONSTRUCTOR_INVOCATION_PROBLEM(Kind.ERROR, 1003,
			"A problem occurred whilst attempting to construct an object of type ''{0}'' using arguments ''{1}''"),

	METHOD_NOT_FOUND(Kind.ERROR, 1004,
			"Method call: Method {0} cannot be found on {1} type"),

	TYPE_NOT_FOUND(Kind.ERROR, 1005,
			"Type cannot be found ''{0}''"),

	FUNCTION_NOT_DEFINED(Kind.ERROR, 1006,
			"The function ''{0}'' could not be found"),

	PROPERTY_OR_FIELD_NOT_READABLE_ON_NULL(Kind.ERROR, 1007,
			"Property or field ''{0}'' cannot be found on null"),

	PROPERTY_OR_FIELD_NOT_READABLE(Kind.ERROR, 1008,
			"Property or field ''{0}'' cannot be found on object of type ''{1}'' - maybe not public?"),

	PROPERTY_OR_FIELD_NOT_WRITABLE_ON_NULL(Kind.ERROR, 1009,
			"Property or field ''{0}'' cannot be set on null"),

	PROPERTY_OR_FIELD_NOT_WRITABLE(Kind.ERROR, 1010,
			"Property or field ''{0}'' cannot be set on object of type ''{1}'' - maybe not public?"),

	METHOD_CALL_ON_NULL_OBJECT_NOT_ALLOWED(Kind.ERROR, 1011,
			"Method call: Attempted to call method {0} on null context object"),

	CANNOT_INDEX_INTO_NULL_VALUE(Kind.ERROR, 1012,
			"Cannot index into a null value"),

	NOT_COMPARABLE(Kind.ERROR, 1013,
			"Cannot compare instances of {0} and {1}"),

	INCORRECT_NUMBER_OF_ARGUMENTS_TO_FUNCTION(Kind.ERROR, 1014,
			"Incorrect number of arguments for function, {0} supplied but function takes {1}"),

	INVALID_TYPE_FOR_SELECTION(Kind.ERROR, 1015,
			"Cannot perform selection on input data of type ''{0}''"),

	RESULT_OF_SELECTION_CRITERIA_IS_NOT_BOOLEAN(Kind.ERROR, 1016,
			"Result of selection criteria is not boolean"),

	BETWEEN_RIGHT_OPERAND_MUST_BE_TWO_ELEMENT_LIST(Kind.ERROR, 1017,
			"Right operand for the 'between' operator has to be a two-element list"),

	INVALID_PATTERN(Kind.ERROR, 1018,
			"Pattern is not valid ''{0}''"),

	PROJECTION_NOT_SUPPORTED_ON_TYPE(Kind.ERROR, 1019,
			"Projection is not supported on the type ''{0}''"),

	ARGLIST_SHOULD_NOT_BE_EVALUATED(Kind.ERROR, 1020,
			"The argument list of a lambda expression should never have getValue() called upon it"),

	EXCEPTION_DURING_PROPERTY_READ(Kind.ERROR, 1021,
			"A problem occurred whilst attempting to access the property ''{0}'': ''{1}''"),

	FUNCTION_REFERENCE_CANNOT_BE_INVOKED(Kind.ERROR, 1022,
			"The function ''{0}'' mapped to an object of type ''{1}'' which cannot be invoked"),

	EXCEPTION_DURING_FUNCTION_CALL(Kind.ERROR, 1023,
			"A problem occurred whilst attempting to invoke the function ''{0}'': ''{1}''"),

	ARRAY_INDEX_OUT_OF_BOUNDS(Kind.ERROR, 1024,
			"The array has ''{0}'' elements, index ''{1}'' is invalid"),

	COLLECTION_INDEX_OUT_OF_BOUNDS(Kind.ERROR, 1025,
			"The collection has ''{0}'' elements, index ''{1}'' is invalid"),

	STRING_INDEX_OUT_OF_BOUNDS(Kind.ERROR, 1026,
			"The string has ''{0}'' characters, index ''{1}'' is invalid"),

	INDEXING_NOT_SUPPORTED_FOR_TYPE(Kind.ERROR, 1027,
			"Indexing into type ''{0}'' is not supported"),

	INSTANCEOF_OPERATOR_NEEDS_CLASS_OPERAND(Kind.ERROR, 1028,
			"The operator 'instanceof' needs the right operand to be a class, not a ''{0}''"),

	EXCEPTION_DURING_METHOD_INVOCATION(Kind.ERROR, 1029,
			"A problem occurred when trying to execute method ''{0}'' on object of type ''{1}'': ''{2}''"),

	OPERATOR_NOT_SUPPORTED_BETWEEN_TYPES(Kind.ERROR, 1030,
			"The operator ''{0}'' is not supported between objects of type ''{1}'' and ''{2}''"),

	PROBLEM_LOCATING_METHOD(Kind.ERROR, 1031,
			"Problem locating method {0} on type {1}"),

	SETVALUE_NOT_SUPPORTED(	Kind.ERROR, 1032,
			"setValue(ExpressionState, Object) not supported for ''{0}''"),

	MULTIPLE_POSSIBLE_METHODS(Kind.ERROR, 1033,
			"Method call of ''{0}'' is ambiguous, supported type conversions allow multiple variants to match"),

	EXCEPTION_DURING_PROPERTY_WRITE(Kind.ERROR, 1034,
			"A problem occurred whilst attempting to set the property ''{0}'': {1}"),

	NOT_AN_INTEGER(Kind.ERROR, 1035,
			"The value ''{0}'' cannot be parsed as an int"),

	NOT_A_LONG(Kind.ERROR, 1036,
			"The value ''{0}'' cannot be parsed as a long"),

	INVALID_FIRST_OPERAND_FOR_MATCHES_OPERATOR(Kind.ERROR, 1037,
			"First operand to matches operator must be a string. ''{0}'' is not"),

	INVALID_SECOND_OPERAND_FOR_MATCHES_OPERATOR(Kind.ERROR, 1038,
			"Second operand to matches operator must be a string. ''{0}'' is not"),

	FUNCTION_MUST_BE_STATIC(Kind.ERROR, 1039,
			"Only static methods can be called via function references. " +
			"The method ''{0}'' referred to by name ''{1}'' is not static."),

	NOT_A_REAL(Kind.ERROR, 1040,
			"The value ''{0}'' cannot be parsed as a double"),

	MORE_INPUT(Kind.ERROR,1041,
			"After parsing a valid expression, there is still more data in the expression: ''{0}''"),

	RIGHT_OPERAND_PROBLEM(Kind.ERROR, 1042,
			"Problem parsing right operand"),

	NOT_EXPECTED_TOKEN(Kind.ERROR, 1043,
			"Unexpected token. Expected ''{0}'' but was ''{1}''"),

	OOD(Kind.ERROR, 1044,
			"Unexpectedly ran out of input"),

	NON_TERMINATING_DOUBLE_QUOTED_STRING(Kind.ERROR, 1045,
			"Cannot find terminating \" for string"),

	NON_TERMINATING_QUOTED_STRING(Kind.ERROR, 1046,
			"Cannot find terminating ' for string"),

	MISSING_LEADING_ZERO_FOR_NUMBER(Kind.ERROR, 1047,
			"A real number must be prefixed by zero, it cannot start with just ''.''"),

	REAL_CANNOT_BE_LONG(Kind.ERROR, 1048,
			"Real number cannot be suffixed with a long (L or l) suffix"),

	UNEXPECTED_DATA_AFTER_DOT(Kind.ERROR, 1049,
			"Unexpected data after ''.'': ''{0}''"),

	MISSING_CONSTRUCTOR_ARGS(Kind.ERROR, 1050,
			"The arguments '(...)' for the constructor call are missing"),

	RUN_OUT_OF_ARGUMENTS(Kind.ERROR, 1051,
			"Unexpected ran out of arguments"),

	UNABLE_TO_GROW_COLLECTION(Kind.ERROR, 1052,
			"Unable to grow collection"),

	UNABLE_TO_GROW_COLLECTION_UNKNOWN_ELEMENT_TYPE(Kind.ERROR, 1053,
			"Unable to grow collection: unable to determine list element type"),

	UNABLE_TO_CREATE_LIST_FOR_INDEXING(Kind.ERROR, 1054,
			"Unable to dynamically create a List to replace a null value"),

	UNABLE_TO_CREATE_MAP_FOR_INDEXING(Kind.ERROR, 1055,
			"Unable to dynamically create a Map to replace a null value"),

	UNABLE_TO_DYNAMICALLY_CREATE_OBJECT(Kind.ERROR, 1056,
			"Unable to dynamically create instance of ''{0}'' to replace a null value"),

	NO_BEAN_RESOLVER_REGISTERED(Kind.ERROR, 1057,
			"No bean resolver registered in the context to resolve access to bean ''{0}''"),

	EXCEPTION_DURING_BEAN_RESOLUTION(Kind.ERROR, 1058,
			"A problem occurred when trying to resolve bean ''{0}'':''{1}''"),

	INVALID_BEAN_REFERENCE(Kind.ERROR, 1059,
			"@ can only be followed by an identifier or a quoted name"),

	TYPE_NAME_EXPECTED_FOR_ARRAY_CONSTRUCTION(Kind.ERROR, 1060,
			"Expected the type of the new array to be specified as a String but found ''{0}''"),

	INCORRECT_ELEMENT_TYPE_FOR_ARRAY(Kind.ERROR, 1061,
			"The array of type ''{0}'' cannot have an element of type ''{1}'' inserted"),

	MULTIDIM_ARRAY_INITIALIZER_NOT_SUPPORTED(Kind.ERROR, 1062,
			"Using an initializer to build a multi-dimensional array is not currently supported"),

	MISSING_ARRAY_DIMENSION(Kind.ERROR, 1063,
			"A required array dimension has not been specified"),

	INITIALIZER_LENGTH_INCORRECT(Kind.ERROR, 1064,
			"array initializer size does not match array dimensions"),

	UNEXPECTED_ESCAPE_CHAR(Kind.ERROR, 1065, "unexpected escape character."),

	OPERAND_NOT_INCREMENTABLE(Kind.ERROR, 1066,
			"the expression component ''{0}'' does not support increment"),

	OPERAND_NOT_DECREMENTABLE(Kind.ERROR, 1067,
			"the expression component ''{0}'' does not support decrement"),

	NOT_ASSIGNABLE(Kind.ERROR, 1068,
			"the expression component ''{0}'' is not assignable"),

	MISSING_CHARACTER(Kind.ERROR, 1069,
			"missing expected character ''{0}''"),

	LEFT_OPERAND_PROBLEM(Kind.ERROR, 1070,
			"Problem parsing left operand"),

	MISSING_SELECTION_EXPRESSION(Kind.ERROR, 1071,
			"A required selection expression has not been specified"),

	EXCEPTION_RUNNING_COMPILED_EXPRESSION(Kind.ERROR,1072,
			"An exception occurred whilst evaluating a compiled expression");


	private final Kind kind;

	private final int code;

	private final String message;


	private SpelMessage(Kind kind, int code, String message) {
		this.kind = kind;
		this.code = code;
		this.message = message;
	}


	/**
	 * Produce a complete message including the prefix, the position (if known)
	 * and with the inserts applied to the message.
	 * @param pos the position (ignored and not included in the message if less than 0)
	 * @param inserts the inserts to put into the formatted message
	 * @return a formatted message
	 */
	public String formatMessage(int pos, Object... inserts) {
		StringBuilder formattedMessage = new StringBuilder();
		formattedMessage.append("EL").append(this.code);
		switch (this.kind) {
			case ERROR:
				formattedMessage.append("E");
				break;
		}
		formattedMessage.append(":");
		if (pos != -1) {
			formattedMessage.append("(pos ").append(pos).append("): ");
		}
		formattedMessage.append(MessageFormat.format(this.message, inserts));
		return formattedMessage.toString();
	}


	public static enum Kind { INFO, WARNING, ERROR }

}
