package bjc.utils.ioutils.format;

import java.io.*;
import java.util.*;

import bjc.utils.ioutils.ReportWriter;

/**
 * Represents an enclosed group of decrees.
 *
 * This is used for all of the decrees that take another format string as part
 * of their body.
 *
 * @author Ben Culkin
 */
public class GroupDecree implements Iterable<ClauseDecree>, Decree {
	/**
	 * The decree that opened this group.
	 */
	public SimpleDecree opening;

	/**
	 * The decree that closed this group.
	 */
	public SimpleDecree closing;

	/**
	 * The clauses that make up the body of this group.
	 */
	public List<ClauseDecree> body;

	/**
	 * Create a new group decree with no values.
	 */
	public GroupDecree() {
		body = new ArrayList<>();
	}

	/**
	 * Create a new group decree with a given body.
	 *
	 * @param children
	 *                 The decrees that form the body of the group.
	 */
	public GroupDecree(ClauseDecree... children) {
		this();

		for (ClauseDecree child : children) body.add(child);
	}

	/**
	 * Create a new group decree with all of the fields filled out.
	 *
	 * @param opening
	 *                 The decree opening the group.
	 *
	 * @param closing
	 *                 The decree closing the group.
	 *
	 * @param children
	 *                 The decree making up the body of the group.
	 */
	public GroupDecree(SimpleDecree opening, SimpleDecree closing, ClauseDecree... children) {
		this(children);

		this.opening = opening;
		this.closing = closing;
	}

	/**
	 * Add a decree to this group.
	 *
	 * @param child
	 *              The decree to add to the group.
	 */
	public void addChild(ClauseDecree child) {
		body.add(child);
	}

	/**
	 * Get the first clause from the group.
	 *
	 * @return The first clause in the group
	 */
	public ClauseDecree clause() {
		return body.get(0);
	}

	/**
	 * Get a specific clause from the group.
	 *
	 * @param idx
	 *            The index of the clause to get.
	 *
	 * @return The clause at that index.
	 */
	public ClauseDecree clause(int idx) {
		return body.get(idx);
	}

	/**
	 * Get the body of the first clause.
	 *
	 * @return The decrees that make up the body of the first clause.
	 */
	public List<SimpleDecree> unwrap() {
		return body.get(0).body;
	}

	@Override
	public String toString() {
		try (ReportWriter writer = new ReportWriter()) {
			String open  = "<null>";
			String close = "<null>";

			if (opening != null) open  = opening.toString();
			if (closing != null) close = closing.toString();

			writer.writef("GroupDecree (opening %s) (closing %s)\n", open, close);
			writer.indent();
			
			int idx = 0;
			for (ClauseDecree clause : body) {
				writer.writef("Clause %d:", idx++);
				
				clause.toReportWriter(writer);
			}

			writer.dedent();

			return writer.toString();
		} catch (IOException ioex) {
			return "<IOEXCEPTION>";
		}
		// return String.format("GroupDecree [opening=%s, closing=%s, body=%s]",
		// opening, closing, body);
	}

	@Override
	public Iterator<ClauseDecree> iterator() {
		return body.iterator();
	}

	/**
	 * Get the number of clauses in this group.
	 *
	 * @return The number of clauses in the group.
	 */
	public int size() {
		return body.size();
	}
}