#include <malloc.h>
#include <fstream>
#include <iostream>
#include <string.h>
#include <conio.h>
#include <stdlib.h>


using namespace std;


struct node 
{
	char item [20];
	int a;
	float b;
	struct node *next;
};

typedef struct node *NODEPTR;

NODEPTR head;
NODEPTR tail;
NODEPTR previous;
NODEPTR current;

struct Data
{
	char fruit[80];
	float count;
	float wholesale;
};

Data D;


//prcedure pre-definitions
int menu();
node *set_pointer();
void traverse_and_print();
void print_first();
void print_last();
void load_data();
void load_initial_data();
void get_data();
void save_file();
void load_file();
void look_me_up();
void out_of_stock();
void update_inventory();

//global variables

int first_entry = 1;
int need_to_save_file = 0;

void main()
{
	int x;

	while (x = menu())
	{
		switch (x)
		{
		case 1:  //load from file 
			load_file();
			break;
		case 2: //add daily purchases
			get_data();
			if (first_entry)
			{
				load_initial_data();
			}
			else
			{
				need_to_save_file = 1;
			}
			break;
		case 3: // to look up item
			if (!first_entry)
			{
				look_me_up();
			}
			break;
		case 4: // delete items no longer in stock
			if (!first_entry)
			{
				out_of_stock();
				need_to_save_file = 1;
			}
			break;
		case 5: // update current inventory list at end of day
			if (!first_entry)
			{
				update_inventory();
				need_to_save_file = 1;
			}
			break;
		case 6: // review last entry
			if (!first_entry)
			{
				print_last();
			}
			break;
		case 7: //save data to disk
			if (!first_entry)
			{
				save_file();
				need_to_save_file = 0;
			}
			break;
		case 8: //print current inventory
			if(!first_entry)
			{
				traverse_and_print();
			}
			break;
		}
	}

	if (need_to_save_file)
	{
		cout<<">>>Warning<<< Saving File! "<<endl;
		save_file();
	}

	cout<<"done!"<<endl;
}



int menu()
{
	int choice;
	cout<<"The Fruit Market "
		<<'\n'
		<<"Link List Processing "
		<<'\n'
		<<'\n'
		<<"0. to Exit"
		<<'\n'
		<<"1. to Load from File"
		<<'\n'
		<<"2. to Add daily purchases"
		<<'\n'
		<<"3. to Lookup item"
		<<'\n'
		<<"4. to Delete out of stock items"
		<<'\n'
		<<"5. to Update inventory"
		<<'\n'
		<<"6. to Reprint last entry"
		<<'\n'
		<<"7. to Save to File"
		<<'\n'
		<<"8. to Print Current Data"
		<<endl;
	cout<<"?";
	cin>>choice;
	return (choice);
}

void print_first()
{
	cout<<"Using head"<<endl;
	cout<< head->item<<'\n'
		<< head->a<<'\n'
		<< head->b<<endl;
	_getch();
}

void print_last()
{
	cout<<"Item Lbs Wholesale Cost" << endl;
	cout<< tail->item<<'\n'
		<< tail->a <<'\n'
		<< tail->b << endl;
	_getch();
}

node *set_pointer()
{
	node *p;
		
		p = new node;
		if(!p)
		{
			cout<<"OOOOOOOOOOOOOps";
			_getch();
			exit(-1);
		}
		return(p);
}
	


void traverse_and_print()
{
	cout<<"Print List"<<endl;
	current=head;
	cout<<"Item  LBS wholesale cost" << endl;
	while (current != NULL)
	{
		cout<<current->item<<'\n'
			<<current->a<<'\n'
			<<current->b<<endl;
		current = current->next;
	}
	_getch();
}


void get_data()
{
	char temp[80];
	cout <<"Enter Fruit Name: ";
	cin >> D.fruit;
	cin.getline (temp,80);
	strcat_s(D.fruit,temp);
	D.fruit[0] = toupper(D.fruit[0]);

	if (D.fruit[strlen(D.fruit)-1] == 's')
	{
		cout<<"How many (whole) pounds of " <<D.fruit<<" did you buy? "<<endl;
	}
	else
	{
		cout<<"How many (whole) pounds of " <<D.fruit<<" did you buy? "<<endl;
	}

	cin>>D.count;
	cout<<"What is the wholesale cost of each pound of "<<D.fruit<<" ? "<<endl;
	cin>>D.wholesale;
}



void save_file()
{
	ofstream FILE("fruit.txt",ios::out);
	current = head;
	while (current != NULL)
	{
		strcpy_s(D.fruit,current->item);
		D.count = current->a;
		D.wholesale = current->b;

		FILE<<D.fruit<<" "<<D.count<< " "<<D.wholesale<<endl;
		current = current->next;
	}
}


void load_intitial_data()
{
	tail=head=current=set_pointer();
	strcpy_s(current->item,D.fruit);
	current->a=D.count;
	current->b=D.wholesale;
	current->next = NULL;
	first_entry = false;
}

void load_data()
{
	previous = tail;
	tail = current = set_pointer();
	previous->next = current;
	strcpy_s(current->item,D.fruit);
	current->a = D.count;
	current->b = D.wholesale;
	current->next = NULL;


}


void load_file()
{
	cout<<"Loading Data from Disk"<<endl;
	ifstream FILE("fruit.txt",ios::in);
	while (FILE>>D.fruit>>D.count>>D.wholesale)
	{
		cout<<D.fruit<<" "<<D.count<<" "<<D.wholesale<<endl;

		if (first_entry)
		{
			load_initial_data();
		}
		else
		{
			load_data();
		}
	}
		cout<<"Data Loaded! "<<endl;
		_getch();
}


void look_me_up()
{
	int x;
	char item[80];
	char item1[80];

	cout<<"Enter name or part of name of fruit: ";
	cin>> item;
	current=head;
	cout<<"Item    LBS  Wholesale cost"<< endl;

	while (current !=NULL)
	{
		strcpy_s(item1,current->item);
		for (x=0; x<strlen(item1);x++)
		{
			item[x]=tolower(item1[x]);
		}
		for (x=0; x<strlen(item); x++)
		{
			item[x]=tolower(item[x]);
		}
		if (strstr(item1,item) != NULL)
		{
			cout<<current->item<<" "<<current->a<<" "
				<<current->b<<endl;
		}
		current = current->next;
	}
	_getch();
}


void out_of_stock()
{
	int x;
	char y_n;
	char item[80];
	char item1[80];

	cout<<"Enter name or part of name of fruit: ";
	cin>>item;
	previous=current=head;
	cout<<"Item  LBS  Wholesale cost"<<endl;
	while (current != NULL)
	{
		strcpy_s(item1,current->item);
		for (x=0; x<strlen(item1);x++)
		{
			item1[x]=tolower(item1[x]);
		}
		for (x=0; x<strlen(item);x++)
		{
			item[x]=tolower(item[x]);
		}
		if (strstr(item1,item) != NULL)
		{
			cout<<current->item<<" "<<current->a<<" "
				<<current->b<<endl;

			cout<<'\n'<<"Are we now out of "<<current->item<<"s?"<<endl;
			cin>>y_n;
			y_n=tolower(y_n);
			if (y_n =='y')
			{
				if((current == head) & (current == tail))
				{
					first_entry = true;
				}
				if (current == head)
				{
					head = current->next;
				}
				if (current == tail)
				{
					previous->next=NULL;
					tail = previous;
				}
				if ((current != head) & (current !=tail))
				{
					previous->next=current->next;
				}
			}
		}

		previous = current;
		current = current->next;
	}
}


void update_inventory()
{
	int x;
	char y_n;
	char item[80];
	char item1[80];


	cout<<"Enter name or part of name of fruit: ";
	cin>>item;
	previous = current = head;
	cout<<"Item  LBS   Wholesale cost"<<endl;

	while (current != NULL)
	{
		strcpy_s(item1,current->item);

		for(x=0;x<strlen(item1);x++)
		{
			item1[x]=tolower(item1[x]);
		}
		for (x=0;x<strlen(item);x++)
		{
			item[x]=tolower(item[x]);
		}

		if (strstr(item,item) !=NULL)
		{
			strcpy_s(D.fruit,current->item);
			D.count=current->a;
			D.wholesale=current->b;
			cout<<D.fruit<<" "<<D.count<<" "<<D.wholesale<<endl;

			if (D.fruit[strlen(D.fruit)-1] == 's')
			{
				cout<<'\n'<<"Do you want to update the number of" << current->item<<"?"<<endl;
			}
			else
			{
				cout<<'\n'<<"Do you want to update the number of" << current->item<<"s?"<<endl;
			}

			cin>>y_n;
			y_n=tolower(y_n);
			if (y_n == 'y')
			{
				cout<<'\n'<<"How many (whole) pounds of "<<D.fruit<<" do you have left? ";
				cin >> current->a;
			}
		}
		previous = current;
		current = current->next;
	}
}