//////////////////////////////////////
////////////Sean Walsh///////////////
////////////////////////////////////

#include <iostream>
#include <fstream>	//opening files
#include <string>	//used for strings
#include <cstddef>	//used for NULL command
using namespace std;

struct NodeType;

struct NodeType		//doubly linked list
{
	string word;
	int freq;
	NodeType* prev;
	NodeType* next;
};

class SortedType
{
public:
	SortedType();
	bool IsEmpty() const;
	int LengthIs() const;
	void FindItem(string& word, int& freq, bool& found);
	void InsertFirst(string newword);
	void InsertItemAfter(string newword);
	void IncFreq();
	void DeleteItem(string word, int& freq);
	void ResetList();
	void GetNextItem(string& word, int& freq, bool& moreNode);
private:
	NodeType *listData;
	int length;
	NodeType* currentPos;
};

SortedType::SortedType()
{
	length=0;
	listData=NULL;
	currentPos=NULL;
}

bool SortedType::IsEmpty() const
{
	return (length==0);
}

int SortedType::LengthIs() const
{
	return length;
}

void SortedType::FindItem(string& word, int& freq, bool& found)
{
	bool moreToSearch;
	NodeType* preLoc;

	preLoc=NULL;
	currentPos=listData;
	moreToSearch=(currentPos!=NULL);
	found=false;

	while(moreToSearch)
	{
		if((currentPos->word)<word)
		{
			preLoc=currentPos;
			currentPos=currentPos->next;
			moreToSearch=(currentPos!=NULL);
		}
		else
		{
			moreToSearch=false;
		}
	}

	if(currentPos==NULL)				//all the words are smaller than search word
	{
		currentPos=preLoc;
	}
	else if(currentPos->word==word)		//found
	{
		found=true;
	}
	else if(currentPos==listData)		//first node is larger than newword
	{
		currentPos=NULL;
	}
	else								//for insertAfter, move one back.
	{
		currentPos=currentPos->prev;
	}
}

void SortedType::InsertFirst(string newword)
{
	//The current list is empty

	NodeType* newNode;

	newNode= new NodeType;
	newNode->word=newword;
	newNode->prev=NULL;
	newNode->next=NULL;
	newNode->freq=1;
	listData=newNode;
}

void SortedType::InsertItemAfter(string newword)
{
	NodeType* newNode;
	NodeType* cpos;
	
	newNode=new NodeType;
	newNode->word=newword;
	newNode->freq=1;

	if(currentPos!=NULL)						//case II and III
	{
		newNode->prev=currentPos;
		newNode->next=currentPos->next;

		if(currentPos->next!=NULL)				//case II
			currentPos->next->prev=newNode;
		
		currentPos->next=newNode;
	}
	else										//case I
	{
		newNode->prev=NULL;
		newNode->next=listData;
		listData->prev=newNode;
		listData=newNode;
	}
	length++;

	//Just for Testing the generation list

	cpos=listData;
	cout<<"Current list is: ";
	while(cpos!=NULL)
	{
		cout<<cpos->word<<" "<<cpos->freq<<", ";
		cpos=cpos->next;
	}
	cin.get();
	cout<<endl;
	
}

void SortedType::IncFreq()
{
	(currentPos->freq) ++;
}

void SortedType::DeleteItem(string word, int& freq)
{


}

void SortedType::ResetList()
{
	currentPos=NULL;
}

void SortedType::GetNextItem(string& word, int& freq, bool& last)
{
	bool moreNode=true;

	//A copy of the next word and freq in the list is returned
	//when the end of list is reached, currentPos is rest to begin
	//and more is false

	if(currentPos==NULL)
	{
		moreNode=false;
		currentPos=listData;
	}
	else
	{
		currentPos=currentPos->next;
		word=currentPos->word;
		freq=currentPos->freq;
		moreNode=true;
	}
}

//Client Code
int main()
{
    SortedType wlist;
	string readword;
	ifstream inF;	//the data file "book.txt"
	ofstream outF;
	bool exist;
	int frequency;
	int selection;	//integer of menu option
	
	
	
	inF.open("a:\book.txt");
	if(!inF)
	{
		cout<<"ERROR! Can't open input file"<<endl;
		return 1;
	}
	inF>>readword;
	while(readword[0]<'A'||readword[0]>'Z')
	{
		inF>>readword;
	}
	cout<<"new word: "<<readword<<endl;
	cin.get();
	wlist.InsertFirst(readword);

	while(!inF.eof())
	{
		inF>>readword;
		while(readword[0]<'A'||readword[0]>'Z')
		{
			inF>>readword;
		}
		cout<<"next word is "<<readword<<endl;
		wlist.FindItem(readword, frequency, exist);
		if(!exist)
		{
			wlist.InsertItemAfter(readword);
		}
		else
		{
			wlist.IncFreq();
		}
	}
	
	//The number of words in the list
	cout<<"The number of nodes in the list is "<<wlist.LengthIs()<<endl;

	//menu
	cout<<"********************"<<endl;
	cout<<"		 <Menu> 	   "<<endl;
	cout<<"********************"<<endl;
	cout<<"1.) Enter the word you want to search"<<endl;
	cout<<"2.) Enter the word you want to delete"<<endl;
	cout<<"3.) Enter the word you want to insert"<<endl;
	cout<<"4.) List all the words with their frequency"<<endl;
	cout<<"5.) Exit"<<endl;
	cin>>selection;
	//end menu

	while(selection!=999)
	{
		switch(selection)
		{
		case 1: cout<<"Enter in the word you want to search for: "<<endl;
            cin>>readword; 
			wlist.FindItem(readword,frequency,exist);
			break;
		case 2: cout<<"Enter in the word you want to delete: "<<endl;
			cin>>readword; 
			wlist.DeleteItem(readword,frequency);
			break;
		case 3: cout<<"Enter in the word you want to insert: "<<endl;
			cin>>readword;
			wlist.InsertItemAfter(readword);
			break;
		case 4: 
			break;
		case 5: cout<<"GoodBye"<<endl;
			selection=999;
			break;
		}
	}
	return 0;

}

inF.open("a:\book.txt");

inF.open("a:\\book.txt");