#include "WordProcessing.h"

#include <algorithm>
#include <functional>

// Comparator struct for alphabetical sorting
// TODO support non ASCII characters in a graceful manner (accents, other alphabets, etc)
struct AlphbeticalStringOrdering
{
	bool operator()(string iLeft, string iRight) const
	{

		string lowerLeft = iLeft, lowerRight = iRight;
		transform(lowerLeft.begin(), lowerLeft.end(), lowerLeft.begin(), ::tolower);
		transform(lowerRight.begin(), lowerRight.end(), lowerRight.begin(), ::tolower);

		/* If the strings are the same in case a case insensitive comparisonthen we can keep the default/basic
		* because we will only compare the case of the letters
		* If they are different in case insensitive we use this as our basis
		* because we do not want to risk having a string starting with a 'Z' before a word starting with an 'a'
		*/
		bool leftSmaller = iLeft < iRight;
		if (lowerLeft != lowerRight)
		{
			leftSmaller = lowerLeft < lowerRight;
		}
		
		return leftSmaller;
	}

};

void WordProcessing::ProcessWords(bool isUnique, vector<string>& ioWords)
{
	std::function<bool(string, string)> sorter = AlphbeticalStringOrdering();
	sort(ioWords.begin(), ioWords.end(), sorter);

	if (isUnique)
	{
		auto eraseIt = unique(ioWords.begin(), ioWords.end());
		ioWords.erase(eraseIt, ioWords.end());
	}
}