/** TernaryLogic.java -- classes that describe a ternary logic system
 *  @author Douglas Jones
 *  @version mp2, 2017-02-21
 *
 *  This code borrows heavily from RoadNetwork.java distributed on 2017-02-10.
 *  The goal in writing this code was to minimally but adequately meet the
 *  requirements of the assignment while avoiding any creative additions to
 *  the framework established by RoadNetwork.java other than bug fixes.
 *  Where RoadNetwork.java contained support for features that were not
 *  mentioned in the assignment (comments, for example), these were deleted.
 */

import java.util.LinkedList;
import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;

/** Utility package for error handling
 */
class Errors {
	private Errors(){}; // you may never instantiate this class

	/** Call this to warn of non fatal errors
	 */
	public static void warn( String message ) {
		System.err.println( "Warning: " + message );
	}

	/** Call this to report fatal errors
	 */
	public static void fatal( String message ) {
		System.err.println( "Fatal error: " + message );
		System.exit( -1 );
	}
}

/** Wires link gates
 *  @see Gate
 *  @see Errors
 *  @see TernaryLogic#findGate(String)
 */
class Wire {
	private final float delay;	// time delay of this wire
	private final Gate destination;	// where wire goes, or null
	private final Gate source;	// source of wire, or null
	// Wire name is the source-destination names

	/** initializer scans and processes one wire definition
	 */
	public Wire( Scanner sc ) {
		// textual names of source and dest
		String srcName;
		String dstName;

		// read names of source and dest, guarantee they're not null
		if (sc.hasNext()) {
			srcName = sc.next();
		} else {
			// error message comes from findGate()
			srcName = "????";
		}
		if (sc.hasNext()) {
			dstName = sc.next();
		} else {
			// error message comes from findGate()
			dstName = "????";
		}

		// lookup and check names of source and dest
		source = TernaryLogic.findGate( srcName );
		if (source == null) {
			Errors.warn(
				"Road '" + srcName +
				"' '" + dstName +
				"' source undefined."
			);
		}
		destination = TernaryLogic.findGate( dstName );
		if (destination == null) {
			Errors.warn(
				"Wire '" + srcName +
				"' '" + dstName +
				"' destination undefined."
			);
		}

		// get delay of wire
		if (sc.hasNextFloat()) {
			delay = sc.nextFloat();
			if (delay < 0.0f) {
				Errors.warn(
					"Wire '" + srcName +
					"' '" + dstName +
					"' '" + delay +
					"' has a negative delay."
				);
			}
		} else {
		} else {
			Errors.warn(
				"Wire '" + srcName +
				"' '" + dstName +
				"' has no delay."
			);
			delay = 99.999f;
		}
		sc.nextLine();
	}

	/** output this wire in a format like that used for input
	 */
	public String toString() {
		String srcName;
		String dstName;

		if (source == null) {
			srcName = "???";
		} else {
			srcName = source.name;
		}

		if (destination == null) {
			dstName = "???";
		} else {
			dstName = destination.name;
		}
		
		return(
			"wire " +
			srcName + " " +
			dstName + " " +
			delay
		);
	}
}

/** Gates are linked by wires
 *  @see Wire
 *  @see TernaryLogic#findGate(String)
 */
class Gate {
	private final LinkedList <Wire> outgoing = new LinkedList <Wire> ();
	// Bug:  Does the gate need a list of incoming wires?
	public final String name;	// the name of the gate
	public final String type;	// the type of the gate
	public final int    inputs;	// the type of the gate
	public final float  delay;	// the type of the gate

	/** initializer scans and processes one gate definition
	 */
	public Gate( Scanner sc ) {
		// get and check gate name
		if (sc.hasNext()) {
			name = sc.next();
		} else {
			Errors.warn(
				"gate has no name"
			);
			name = "?????";
		}
		if (TernaryLogic.findGate( name ) != null) {
			Errors.warn(
				"Gate '" + name +
				"' redefined."
			);
		}

		// get and check gate type
		if (sc.hasNext()) {
			type = sc.next();
		} else {
			// the warning for wrong type will come from below
			type = "????";
		}
		if ( (!"min".equals( type )      )  // check for illegal name
		&&   (!"max".equals( type )      )
		&&   (!"neg".equals( type )      )
		&&   (!"istrue".equals( type )   )
		&&   (!"isunknown".equals( type ))
		&&   (!"isfalse".equals( type )  ) ) {
			Errors.warn(
				"Gate '" + name +
				"' '" + type +
				"' has an illegal type."
			);
		}

		// get and check gate input count
		if (sc.hasNextInt()) {
			inputs = sc.nextInt();
		} else {
			inputs = 9999;
			Errors.warn(
				"Gate '" + name +
				"' '" + type +
				"' has no input count."
			);
		}

		// get and check gate delay
		if (sc.hasNextFloat()) {
			delay = sc.nextFloat();
			if (delay < 0.0f) {
				Errors.warn(
					"Gate '" + name +
					"' '" + type +
					"' '" + inputs +
					"' '" + delay +
					"' has a negative delay."
				);
			}
		} else {
			delay = 99.999f;
			Errors.warn(
				"Gate '" + name +
				"' '" + type +
				"' '" + inputs +
				"' has no delay."
			);
		}

		sc.nextLine();
	}

	/** output this Intersection in a format like that used for input
	 */
	public String toString() {
		return(
			"gate " + name +
			" " + type +
			" " + inputs +
			" " + delay
		);
	}
}

/** TernaryLogic -- main program that reads and writes a ternary logic system
 *  @see Wire
 *  @see Gate
 *  @see Errors
 *  @see #main
 */
public class TernaryLogic {
	// lists of roads and intersectins
	static LinkedList <Wire> wires
		= new LinkedList <Wire> ();
	static LinkedList <Gate> gates
		= new LinkedList <Gate> ();

	/** utility method to look up an gate by name
	 *  @param s is the name of the gate, a string
	 *  @return is the Gate object with that name
	 */
	public static Gate findGate( String s ) {
		for ( Gate g: gates ) {
			if (g.name.equals( s )) return g;
		}
		return null;
	}

	/** read a ternary logic system
	 */
	public static void initializeTernary( Scanner sc ) {
		while (sc.hasNext()) {
			// until we hit the end of the file
			String command = sc.next();
			if ("gate".equals( command )) {
				gates.add( new Gate( sc ) );

			} else if ("wire".equals( command )) {
				wires.add( new Wire( sc ) );

			} else {
				Errors.warn(
					"Command '" + command +
					"' is not gate or wire"
				);
			}
		}
	}

	/** write out a ternary logic system
	 */
	public static void writeTernary() {
		for ( Gate g: gates ) {
			System.out.println( g.toString() );
		}
		for ( Wire w: wires ) {
			System.out.println( w.toString() );
		}
	}

	/** main program that reads and writes a road network
	 *  @param args the command line arguments must hold one file name
	 */
	public static void main( String[] args ) {
		// verify that the argument exists.
		if (args.length < 1) {
			Errors.fatal( "Missing file name on command line" );

		} else if (args.length > 1) {
			Errors.fatal( "Unexpected command line args" );

		} else try {
			initializeTernary( new Scanner( new File( args[0] ) ) );
			writeTernary();

		} catch (FileNotFoundException e) {
			Errors.fatal( "Could not read '" + args[0] + "'" );
		}
	}
}