package org.simantics.spreadsheet.graph;

import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Optional;

import org.simantics.spreadsheet.graph.formula.FormulaError2;
import org.simantics.spreadsheet.graph.formula.SpreadsheetEvaluationEnvironment;
import org.simantics.spreadsheet.graph.parser.ast.AstValue;
import org.simantics.spreadsheet.resource.SpreadsheetResource;
import org.simantics.spreadsheet.util.SpreadsheetUtils;

public class SpreadsheetCell implements SpreadsheetElement, SheetNode {

	private static final long serialVersionUID = 6616793596542239339L;

	public static SpreadsheetCell EMPTY;
	
	static {
	    EMPTY = new SpreadsheetCell(null, -1);
	    EMPTY.setContent("");
	    EMPTY.setStyle(SpreadsheetStyle.empty().getStyleId());
	}
	
	private boolean inProgress = false;
	private int iterations = 0;
	
	final private SpreadsheetLine line;
	final private int column;
	int style;
	Object content;
	final private Map<String, SheetNode> properties;
	
	public SpreadsheetCell(SpreadsheetLine line, int column) {
		this.properties = createProperties();
		this.line = line;
		this.column = column;
	}

	//All SpreadsheetCells have these properties - create them when object is created
	private Map<String, SheetNode> createProperties() {
	    Map<String, SheetNode> p = new HashMap<>();	    
	    p.put("typeURI", new SpreadsheetTypeNode(SpreadsheetResource.URIs.Cell));
	    p.put("content", new SpreadsheetCellContent(this));
        p.put("style", new SpreadsheetCellStyle(this));
        p.put("editable", new SpreadsheetCellEditable(this));
        return p;
	}
	
    public boolean hasExpression() {
		return content instanceof SpreadsheetFormula || content instanceof SpreadsheetSCLConstant; 
	}
	
	public void setContent(Object newContent) {
//       if(newContent != null) {
//            if (!(newContent instanceof Serializable)) {
//                throw new AssertionError("content not instanceof Serializable but it is " + newContent.getClass().getSimpleName());
//            }
//        }
	    if (GraphUI.DEBUG)
	        System.out.println("SpreadsheetCell.setContent "+ this + " " + newContent);
		this.content = newContent;
	}

	@Override
	public String getName() {
		return SpreadsheetUtils.cellName(line.row, column);
	}

	@Override
	public Map<?, ?> getChildren() {
		return Collections.emptyMap();
	}
	
	private static String[] keys = { "typeURI", "content" };
	
	@Override
	public Map<String, SheetNode> getProperties() {
	    if (GraphUI.DEBUG)
	        System.out.println("SpreadsheetCell.getProperties: " + this + " " + content + " " + style);
	    return properties; //Return this SpreadsheetCells's properties, rather than a new HashMap
	}
	
	public SpreadsheetBook getBook() {
		return line.getEngine().getBook();
	}

	public SpreadsheetEngine getEngine() {
		return line.getEngine();
	}

	public <T> T evaluate(SpreadsheetEvaluationEnvironment env) {
		return evaluate(env, null);
	}

	public <T> T evaluate(SpreadsheetEvaluationEnvironment env, CellValueVisitor caller) {
//	    System.err.println(getEngine().getName() + ":" + getName() + ": evaluate");
		if(caller != null)
			caller.addReference(makeReferenceKey());
		if(content instanceof SpreadsheetFormula) {
			SpreadsheetFormula f = (SpreadsheetFormula)content;
			if(f.result == null) {
				CellValueVisitor visitor = new CellValueVisitor(env, this);
				AstValue value = ((SpreadsheetFormula)content).value;
				if(this.inProgress == true) this.iterations++;
				
				if(!env.getBook().isIterationEnabled()){
					if(this.inProgress == false){
						this.inProgress = true;
						f.result = value.accept(visitor);
					}
					else f.result = FormulaError2.CIRCULAR_REF.getString();
				}
				else if(this.iterations<env.iterationLimit){
					this.inProgress = true;
					f.result = value.accept(visitor);
				}
				else {
					if(f.result==null)
						f.result = 0.0;
				}
				
				env.getBook().registerReferences(makeReferenceKey(), visitor.getReferences());
			}
			this.inProgress = false;
			this.iterations = 0;
			return (T)f.result;
		} else if (content instanceof SpreadsheetSCLConstant) {
		    SpreadsheetSCLConstant sclConstant = (SpreadsheetSCLConstant) content;
		    return (T) sclConstant.content;
		} else {
			this.inProgress = false;
			return (T)content;
		}
	}
	
	public long makeReferenceKey() {
		SpreadsheetBook book = getBook();
		SpreadsheetEngine engine = getEngine();
		long engineIndex = book.getEngineIndex(engine);
		long row = line.row;
		long col = column;
		return (engineIndex << 40) + (row << 20) + col; 
	}
	
	public void invalidate() {
		getEngine().rangeCache = null;
		if(content instanceof SpreadsheetFormula) {
			SpreadsheetFormula f = (SpreadsheetFormula)content;
			f.result = null;
		}
	}

	@Override
	public void accept(SpreadsheetVisitor v) {
		v.visit(this);
	}

    @Override
    public Optional<SpreadsheetElement> getParent() {
        return Optional.of(line);
    }

    @Override
    public List<SpreadsheetElement> getSpreadsheetChildren() {
        return Collections.emptyList();
    }

    @Override
    public void remove(SpreadsheetElement child) {
        // TODO Auto-generated method stub
        
    }

    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + column;
        result = prime * result + ((line == null) ? 0 : line.hashCode());
        return result;
    }

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

    public void setStyle(int styleId) {
        this.style = styleId;
    }

    public int getStyle() {
        return style;
    }

    public Object getContent() {
        return content;
    }
    
    public static SpreadsheetCell empty(SpreadsheetLine line, int column) {
        SpreadsheetCell cell =  new SpreadsheetCell(line, column);
        cell.setContent("");
        cell.setStyle(SpreadsheetStyle.empty().getStyleId());
        return cell;
    }

}