/*
 * Copyright 2012-2017 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.boot.origin;

import org.springframework.core.io.Resource;
import org.springframework.util.ObjectUtils;

/**
 * {@link Origin} for an item loaded from a text resource. Provides access to the
 * original {@link Resource} that loaded the text and a {@link Location} within it.
 *
 * @author Madhura Bhave
 * @author Phillip Webb
 * @since 2.0.0
 */
public class TextResourceOrigin implements Origin {

	private final Resource resource;

	private final Location location;

	public TextResourceOrigin(Resource resource, Location location) {
		this.resource = resource;
		this.location = location;
	}

	/**
	 * Return the resource where the property originated.
	 * @return the text resource or {@code null}
	 */
	public Resource getResource() {
		return this.resource;
	}

	/**
	 * Return the location of the property within the source (if known).
	 * @return the location or {@code null}
	 */
	public Location getLocation() {
		return this.location;
	}

	@Override
	public int hashCode() {
		int result = 1;
		result = 31 * result + ObjectUtils.nullSafeHashCode(this.resource);
		result = 31 * result + ObjectUtils.nullSafeHashCode(this.location);
		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj) {
			return true;
		}
		if (obj == null) {
			return false;
		}
		if (obj instanceof TextResourceOrigin) {
			TextResourceOrigin other = (TextResourceOrigin) obj;
			boolean result = true;
			result = result && ObjectUtils.nullSafeEquals(this.resource, other.resource);
			result = result && ObjectUtils.nullSafeEquals(this.location, other.location);
			return result;
		}
		return super.equals(obj);
	}

	@Override
	public String toString() {
		StringBuilder result = new StringBuilder();
		result.append(this.resource == null ? "unknown resource [?]"
				: this.resource.getDescription());
		if (this.location != null) {
			result.append(":").append(this.location);
		}
		return result.toString();
	}

	/**
	 * A location (line and column number) within the resource.
	 */
	public final static class Location {

		private final int line;

		private final int column;

		/**
		 * Create a new {@link Location} instance.
		 * @param line the line number (zero indexed)
		 * @param column the column number (zero indexed)
		 */
		public Location(int line, int column) {
			this.line = line;
			this.column = column;
		}

		/**
		 * Return the line of the text resource where the property originated.
		 * @return the line number (zero indexed)
		 */
		public int getLine() {
			return this.line;
		}

		/**
		 * Return the column of the text resource where the property originated.
		 * @return the column number (zero indexed)
		 */
		public int getColumn() {
			return this.column;
		}

		@Override
		public int hashCode() {
			return (31 * this.line) + this.column;
		}

		@Override
		public boolean equals(Object obj) {
			if (this == obj) {
				return true;
			}
			if (obj == null || getClass() != obj.getClass()) {
				return false;
			}
			Location other = (Location) obj;
			boolean result = true;
			result = result && this.line == other.line;
			result = result && this.column == other.column;
			return result;
		}

		@Override
		public String toString() {
			return (this.line + 1) + ":" + (this.column + 1);
		}

	}

}
