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#include "SubstringFunction.h"

using namespace std;

//****************************************************************************************//
//								Component Class											  //	
//****************************************************************************************//
SubstringFunction::SubstringFunction(int start, int length) : AbsFunctionComponent() {

	this->SetStart(start);
	this->SetLength(length);
}

SubstringFunction::~SubstringFunction() {
}

// ***************************************************************************************	//
//								 Public members												//
// ***************************************************************************************	//
int SubstringFunction::GetStart() {
	return this->start;
}

void SubstringFunction::SetStart(int start) {

	this->start = start;
}

int SubstringFunction::GetLength() {

	return this->length;
}

void SubstringFunction::SetLength(int length) {

	this->length = length;
}

ComponentValue* SubstringFunction::ComputeValue() {

	StringVector* values = NULL;
	
	AbsComponent* component = this->GetComponents()->at(0);

	ComponentValue* componentValue = component->ComputeValue();

	// create and populate a result ComponentValue
	ComponentValue* result = new ComponentValue();
	result->SetFlag(componentValue->GetFlag());
	result->AppendMessages(componentValue->GetMessages());

	if(componentValue->GetFlag() == OvalEnum::FLAG_COMPLETE) {
		values = new StringVector();;

		StringVector::iterator iterator;
		for(iterator = componentValue->GetValues()->begin(); iterator != componentValue->GetValues()->end(); iterator++) {
			string currentValue = (*iterator);
			string newValue = "";
			
			// Initialize substring_start to the first character in the string.  This case applies if substring_start is less than or equal to 1.
			int start = 0;

			// Initialize substring_length to the length of the string.  This case applies if substring_length is less than 0 or greater than or equal to the length of the string.
			// It is important that this is a signed type, because the start
			// index may be negative, which will compare wrong with an unsigned type.
			// (and we hope these strings aren't so gigantic a signed int can't hold
			//  its length!)
			int len = currentValue.length();
			
			// If start is larger than the length of the string, throw exception
			if ( this->GetStart() > len)
				throw Exception("Substring start index too large ("+Common::ToString(this->GetStart())+") for string value:\n"+currentValue, OvalEnum::LEVEL_ERROR);
			// otherwise, if substring_start is greater than 1 use the specified value.
			else if ( this->GetStart() > 1 )
				start = this->GetStart() - 1;

			// If substring_length is greater than -1 and less than the the length of the string use the specified value.
			if ( ( this->GetLength() > -1 ) && ( this->GetLength() < len ) ) len = this->GetLength(); 

			newValue = currentValue.substr(start,len);		
			values->push_back(newValue);
		}
		result->SetValues(values);
	}

	delete componentValue;

	return result;	
}

void SubstringFunction::Parse(DOMElement* componentElm) {

	// get the start and length attrs
	string start = XmlCommon::GetAttributeByName(componentElm, "substring_start");
	this->SetStart(atoi(start.c_str()));
	string length = XmlCommon::GetAttributeByName(componentElm, "substring_length");
	this->SetLength(atoi(length.c_str()));

	// Loop through all child elements
	// there should only ever be one 
	DOMNodeList *componentElms = componentElm->getChildNodes();
	unsigned int index = 0;
	while(index < componentElms->getLength()) {
		DOMNode *tmpNode = componentElms->item(index);
		if (tmpNode->getNodeType() == DOMNode::ELEMENT_NODE) {
			DOMElement *childElm = (DOMElement*)tmpNode;

			// Call the ComponentFactory
			AbsComponent* absComponent = ComponentFactory::GetComponent(childElm);
			// store the returned component
			this->AppendComponent(absComponent);			
		}
		index ++;
	}
}

VariableValueVector* SubstringFunction::GetVariableValues() {
	
	VariableValueVector* values = new VariableValueVector();
	AbsComponentVector* components = this->GetComponents();
	AbsComponentVector::iterator iterator;
	for(iterator = components->begin(); iterator != components->end(); iterator++) {
		AbsComponent* component = (AbsComponent*)(*iterator);
		VariableValueVector* tmp = component->GetVariableValues();
		VariableValueVector::iterator varIterator;
		for(varIterator = tmp->begin(); varIterator != tmp->end(); varIterator++) {
			values->push_back((*varIterator));
		}
		// BUG - These can not currenrtly be deleted. 
		// The code is no consistant here. In places a new vector is returned
		// in others a reference to a vector that is managed by other code is returned.
		//delete tmp;
		//tmp = NULL;
	}

	return values;
}
