package org.simantics.spreadsheet.graph.formula;

import org.simantics.databoard.binding.mutable.Variant;
import org.simantics.spreadsheet.graph.CellFormulaFunction;
import org.simantics.spreadsheet.graph.CellValueVisitor;
import org.simantics.spreadsheet.graph.SpreadsheetGraphUtils;
import org.simantics.spreadsheet.graph.SpreadsheetMatrix;
import org.simantics.spreadsheet.graph.parser.ast.AstArgList;

public class MatchFormulaFunction implements CellFormulaFunction<Object>{
	
	@Override
    public Object evaluate(CellValueVisitor visitor, AstArgList args) {
        if (args.values.size() < 2 || args.values.size() > 3) throw new IllegalStateException();
        
        SpreadsheetMatrix lookup_array = (SpreadsheetMatrix) args.values.get(1).accept(visitor);
        if(lookup_array.getWidth()!=1 && lookup_array.getHeight()!=1) return FormulaError2.NA.getString();
        
        Object lookup_value = args.values.get(0).accept(visitor);
        
        int match_type = 1;
        try{
        	if(args.values.size()==3){
        		int matchArg = ((Number)args.values.get(2).accept(visitor)).intValue();
        		if(matchArg<0)
        			match_type = -1;
        		else if(matchArg>0)
        			match_type = 1;
        		else
        			match_type = 0;
        	}
        } catch(Exception e) {
        	return FormulaError2.NA.getString();
        }

        boolean useHeight = false;
        if(lookup_array.getWidth()==1) useHeight = true;
        
        int max = 0;
        if(useHeight) max = lookup_array.getHeight();
        else max = lookup_array.getWidth();

        Integer pos = null;
        if(lookup_value instanceof Variant){
        	Object obj = ((Variant)lookup_value).getValue();
        	Number nVal = SpreadsheetGraphUtils.asValidNumber(obj);
        	if(nVal!=null) obj = nVal;
        	else obj = obj.toString();
        }
        
        if(lookup_value instanceof Number){
        	Double previousValue = null;
        	Double closestMatch = null;
            Double lookup = ((Number)lookup_value).doubleValue();
            int indexWhereCorrectOrderStartsAt = 0;
            
            if(match_type!=0) {
            	for(int i = 0; i < max;i++){
            		Double currValue = null;
                	Number currNum;
                		if(useHeight){
                			currNum = SpreadsheetGraphUtils.asValidNumber(lookup_array.get(i,0));
                		} else {
                			currNum = SpreadsheetGraphUtils.asValidNumber(lookup_array.get(0,i));
                		}
                		if(currNum!=null){
                			currValue = currNum.doubleValue();
                		if(currValue != null){
                			if(previousValue!=null){
                				if((match_type==-1 && currValue>previousValue) || (match_type==1 && currValue<previousValue))
                					indexWhereCorrectOrderStartsAt = i;
                				else
                					break;
                			}
                			previousValue = currValue;
                		}
                	}
            	}
            }
            int begin = indexWhereCorrectOrderStartsAt;
            
            for(int i = begin; i < max;i++){
                Double currValue = null;
                Number currNum;
                	if(useHeight){
                		currNum = SpreadsheetGraphUtils.asValidNumber(lookup_array.get(i,0));
                	} else {
                		currNum = SpreadsheetGraphUtils.asValidNumber(lookup_array.get(0,i));
                	}
                	if(currNum!=null){
                		currValue = currNum.doubleValue();
                	if(currValue != null){
                		if(previousValue==null) previousValue = currValue;
                		if((match_type==-1 && currValue>previousValue) || (match_type==1 && currValue<previousValue)){
                			if(pos!=null)
                				return pos+1;
                	        previousValue = currValue;
                		}
                			int comp = lookup.compareTo(currValue);
                			if(comp == 0){
                				closestMatch = currValue;
                				pos = i;
                			}
                			else if((comp > 0 && match_type==1) || (comp<0 && match_type==-1)){
                				if(closestMatch==null && pos==null){
                					closestMatch = currValue;
                					pos = i;
                				}
                				else if((currValue.compareTo(closestMatch)>=0 && match_type==1) || (currValue.compareTo(closestMatch)<=0 && match_type==-1)){
                					closestMatch = currValue;
                					pos = i;
                				}
                			}
                		previousValue = currValue;
                	}
                }
            }
        }
            
        else if(lookup_value instanceof String){
        	String previousValue = null;
        	String closestMatch = null;
            String lookup = (String)lookup_value;
            int indexWhereCorrectOrderStartsAt = 0;
            
            if(match_type!=0) {
            	for(int i = 0; i < max;i++){
            		String currValue = null;
            		Object obj;
            		if(useHeight){
            			obj = lookup_array.get(i,0);
            		} else {
            			obj = lookup_array.get(0,i);
            		}
            		if(obj instanceof Variant){
            			obj = ((Variant)obj).getValue();
            		}
            		if(obj!=null && !(obj instanceof Number)){
            			currValue = obj.toString();
            			currValue = currValue.toLowerCase();
            		}
            		if(currValue != null && !currValue.equals("")){
            			if(previousValue!=null){
            				if((match_type==-1 && currValue.compareTo(previousValue)>0) || (match_type==1 && currValue.compareTo(previousValue)<0))
            					indexWhereCorrectOrderStartsAt = i;
            				else
            					break;
                		}
                		previousValue = currValue;
                	}
            	}
            }
            
            int begin = indexWhereCorrectOrderStartsAt;

            for(int i = begin; i < max;i++){
            	String currValue = null;
    			Object obj;
    			if(useHeight){
    				obj = lookup_array.get(i,0);
    			} else {
    				obj = lookup_array.get(0,i);
    			}
    			if(obj instanceof Variant){
    				obj = ((Variant)obj).getValue();
    			}
    			if(obj!=null && !(obj instanceof Number)){
    				currValue = obj.toString();
    				currValue = currValue.toLowerCase();
    			}

                if(currValue != null && !currValue.equals("")){
                	if(previousValue==null) previousValue = currValue;
                	if((match_type==-1 && currValue.compareTo(previousValue)>0) || (match_type==1 && currValue.compareTo(previousValue)<0)){
                		if(pos!=null)
                			return pos+1;
                	    previousValue = currValue;
                	}
                	int comp = lookup.compareTo(currValue);
                	if(comp == 0){
                		closestMatch = currValue;
                		pos = i;
                	}
                		else if((comp > 0 && match_type==1) || (comp<0 && match_type==-1)){
                			if(closestMatch==null && pos==null){
                				closestMatch = currValue;
                				pos = i;
                			}
                			else if((currValue.compareTo(closestMatch)>=0 && match_type==1) || (currValue.compareTo(closestMatch)<=0 && match_type==-1)){
                				closestMatch = currValue;
                				pos = i;
                			}
                		}
                	previousValue = currValue;
                }
            }
        }

        if(pos==null)return FormulaError2.NA.getString();
        return pos+1;
    }
}