package slangc.parser;

import slang.streams.SyncOutput;
import slang.streams.SyncInput;
import slang.data.SimpleEnum;

public abstract class Node {
	public Object userdata;
	Annotation[] annotations = null;
	
	Node() {
		// TODO Auto-generated constructor stub
	}
	
	public abstract NodeType getNodeType();

	public abstract String toString();

    private static byte[] inbuffer = new byte[1];

	static SimpleEnum[] toknums = TokenType.values(TokenType.class);
	static SimpleEnum[] nnums = NodeType.values(NodeType.class);

    public static Node loadBinary(Scan sc, SyncInput<byte> inp) {
        inp.readBuffer(inbuffer, 0, 1);
        if (((int) inbuffer[0]) < 0) {
            int toknum = (-(int)inbuffer[0]) - 1;
			//Log.line("Read number " + inbuffer[0] + " as " + toknum);
			if (toknum == 127) {
				inp.readBuffer(inbuffer, 0, 1);
				toknum = (-(int)inbuffer[0]) - 1;
				TokenType tt = (TokenType)toknums[toknum]; //TokenType.lookup(TokenType.class, toknum);
            	return Token.loadBinaryLong(sc, tt, inp);
			} else {
				TokenType tt = (TokenType)toknums[toknum]; //TokenType.lookup(TokenType.class, toknum);
            	return Token.loadBinaryShort(sc, tt, inp);
			}
        } else {
            int top = (int)(inbuffer[0] & 0xFF);
            inp.readBuffer(inbuffer, 0, 1);
            int nnum = (top << 8) | (int)(inbuffer[0] & 0xFF);
            NodeType nt = (NodeType)nnums[nnum]; //NodeType.lookup(NodeType.class, nnum);
            return Branch.loadBinary(sc, nt, inp);
        }
    }

    public abstract void dumpBinary(SyncOutput<byte> o) {
        throw new Error("Can't dump AST nodes of type " + Type.of(this).fullName());
    }
	
	public int countAnnotations() {
		if (annotations == null) {
			return 0;
		} else {
			return annotations.length;
		}
	}
	
	public Annotation[] getAnnotations(AnnotationType type) {
		Annotation[] result = new Annotation[0];
		for (int i = 0; i < countAnnotations(); i++) {
			Annotation a = getAnnotation(i);
			if (a.getAnnotationType() == type) {
				Annotation[] nresult = new Annotation[result.length + 1];
				for (int j = 0; j < result.length; j++) {
					nresult[j] = result[j];
				}
				nresult[nresult.length - 1] = a;
				result = nresult;
			}
		}
		return result;
	}
	
	public int deleteAnnotations(AnnotationType type) {
		int ndeleted = 0;
		Annotation[] result = new Annotation[0];
		for (int i = 0; i < countAnnotations(); i++) {
			Annotation a = getAnnotation(i);
			if (a.getAnnotationType() == type) {
				ndeleted++;
			} else {
				Annotation[] nresult = new Annotation[result.length + 1];
				for (int j = 0; j < result.length; j++) {
					nresult[j] = result[j];
				}
				nresult[nresult.length - 1] = a;
				result = nresult;
			}
		}
		annotations = result;
		return result.length;
	}
	
	public int countAnnotations(AnnotationType type) {
		return getAnnotations(type).length;
	}
	
	public int countErrorsHere() {
		return countAnnotations(AnnotationType.ERROR);
	}
	
	public int deleteErrorsHere() {
		return deleteAnnotations(AnnotationType.ERROR);
	}
	
	public int countErrorsRecursively() {
		return countErrorsHere();
	}
	
	public int deleteErrorsRecursively() {
		return deleteErrorsHere();
	}

	public Node annotate(ErrorType e) {
		return annotate(new ErrorAnnotation(e));
	}
	
	public Node annotate(ErrorType e, String n) {
		ErrorAnnotation a = new ErrorAnnotation(e);
		a.annotate(n);
		return annotate(a);
	}
	
	public Node annotate(WarningType w) {
		return annotate(new WarningAnnotation(w));
	}
	
	public Node annotate(WarningType w, String n) {
		WarningAnnotation a = new WarningAnnotation(w);
		a.annotate(n);
		return annotate(a);
	}
	
	public Node annotate(String note) {
		return annotate(new NoteAnnotation(note));
	}

    /* As a special optimisation, we set a global flag when an error is found.
     * This means that if no errors have been found in this run, looking for/counting errors in
     * the tree can be avoided entirely!
     */
    public static boolean mightHaveErrors = true;
    public static boolean mightHaveWarnings = false;

	public Node annotate(Annotation n) {
        if (n instanceof ErrorAnnotation) {
            mightHaveErrors = true;
        }
        if (n instanceof WarningAnnotation) {
            mightHaveWarnings = true;
        }
		if (annotations == null || annotations.length < 1) {
			annotations = new Annotation[] {n};
			return this;
		}
		Annotation[] nsubnodes = new Annotation[annotations.length + 1];
		for (int i = 0; i < annotations.length; i++) {
			nsubnodes[i] = annotations[i];
		}
		nsubnodes[nsubnodes.length - 1] = n;
		annotations = nsubnodes;
		return this;
	}

	public Annotation getAnnotation(int i) {
		if (i < 0 || i >= countAnnotations()) {
			return null;
		} else {
			return annotations[i];
		}
	}
}