// Classes are enumerated. WARRIOR = 0; RANGER = 1, etc.
typedef enum ClassEnum  {
    WARRIOR,
    RANGER,
    MAGE,
    ACCOUNTANT
} class;

// Player Structure
typedef struct playerStructure {
    char name[50];
    class class;
    int health;
    int mana;
    int attack;    // NEWː Attack power.
    int defense;   // NEWː Resistance to attack.
} player;

// Creates player and sets class.
player* NewPlayer(class class, char name[50]) {
    // Allocate memory to player pointer.
    player *tempPlayer = malloc(sizeof(player));
    SetName(tempPlayer, name);

    // Assign stats based on the given class.
    switch(class) {
    case WARRIOR:
        tempPlayer->health = 60;
        tempPlayer->mana = 0;
        tempPlayer->attack = 3;
        tempPlayer->defense = 5;
        tempPlayer->class = WARRIOR;
        break;
    case RANGER:
        tempPlayer->health = 35;
        tempPlayer->mana = 0;
        tempPlayer->attack = 3;
        tempPlayer->defense = 2;
        tempPlayer->class = RANGER;
        break;
    case MAGE:
        tempPlayer->health = 20;
        tempPlayer->mana = 60;
        tempPlayer->attack = 5;
        tempPlayer->defense = 0;
        tempPlayer->class = MAGE;
        break;
    case ACCOUNTANT:
        tempPlayer->health = 100;
        tempPlayer->mana = 100;
        tempPlayer->attack = 5;
        tempPlayer->defense = 5;
        tempPlayer->class = ACCOUNTANT;
        break;
    default:
      tempPlayer->health = 10;
        tempPlayer->mana = 0;
        tempPlayer->attack = 0;
        tempPlayer->defense = 0;
        break;
    }

    return(tempPlayer); // Return memory address of player.
}

void DisplayStats(player *target)  {
  printf("%s\nHealth: %d\nMana: %d\n\n", target->name, target->health, target->mana);
}

int SetName(player *target, char name[50]) {
  strcpy(target->name, name);
  return(0);
}

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "gameProperties.h"
#include "players.h"

// Function Prototype
int Fight (player *Attacker, player ̈*Target);
 
int main () {
    player *Hero = NewPlayer(WARRIOR, "Sir Leeroy");
    player *Villain = NewPlayer(RANGER, "Sir Jenkins");

    DisplayStats(Villain);   // Before the fight.
    Fight(Hero, Villain);    // FIGHTǃ
    DisplayStats(Villain);   // After the fight.
    return(0);
}

int Fight (player *Attacker, player *Target) {
    int EffectiveAttack; // How much damage we can deal is the difference between the attack of the attacker
                         // And the defense of the target. In this case 5 - 1 = 4 = EffectiveAttack.
 
    EffectiveAttack = Attacker->attack - Target->defense;
    Target->health = Target->health - EffectiveAttack;
    return(0);
}

Name: Sir Jenkins
Health: 35
Mana: 0
Name: Sir Jenkins
Health: 34         // An impressive 1 damage dealt. 
Mana: 0

int Fight(player *Attacker, player *Target) {
    int EffectiveAttack = Attacker->attack - Target->defense;
 
    while (Target->health > 0) {
        DisplayFightMenu();
        
        // Get input.
        int choice;
        printf(">> "); // Indication the user should type something.
        fgets(line, sizeof(line), stdin);
        sscanf(line, "%d", &choice);
 
        switch (choice) {
        case 1:
            Target->health = Target->health - EffectiveAttack;
            printf("%s inflicted %d damage to %s.\n", Attacker->name, EffectiveAttack, Target->name);
            DisplayStats(Target);
            break;
        case 2:
            printf("Running away!\n");
            return(0);
        default:
            printf("Bad input. Try again.\n");
            break;
        }
    }
   
   // Victoryǃ
   if (Target->health <= 0) {
     printf("%s has bested %s in combat.\n", Attacker->name, Target->name) ;
   }
 
      return(0);
}
 
void DisplayFightMenu () {
printf("1) Attack\n2) Run\n");
}

 bool autoPilot;

static int PlayersCreated = 0; // Keep track of players created.
if (PlayersCreated > 0) {
    tempPlayer->autoPilot = true;
} else {
    tempPlayer->autoPilot = false;
}
++PlayersCreated;

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include "gameProperties.h"
#include "players.h"

// Function Prototype
void DisplayStats(player Target);
int Fight(player *Attacker, player *Target);
void DisplayFightMenu(void);

// Global Variables
char line[50];	  // This will contain our input.

int main () {
    player *Hero = NewPlayer(WARRIOR, "Sir Leeroy");
    player *Villain = NewPlayer(RANGER, "Sir Jenkins");
 
    DisplayStats(Villain);   // Before the fight.
    Fight(Hero, Villain);    // FIGHTǃ

  return(0);
}

int Fight(player *Attacker, player *Target) {
   int EffectiveAttack = Attacker->attack - Target->defense;

   while (Target->health > 0) {

      // Get user input if autopilot is set to false.
      if (Attacker->autoPilot == false) {
	 DisplayFightMenu();

	 int choice;
	 printf(">> "); // Sharp brackets indicate that the user should type something.
	 fgets(line, sizeof(line), stdin);
	 sscanf(line, "%d", &choice);

	 switch (choice) {
	   case 1:
	     Target->health = Target->health - EffectiveAttack;
	     printf("%s inflicted %d damage to %s.\n", Attacker->name, EffectiveAttack, Target->name);
	     DisplayStats(Target);
	     break;
	   case 2:
	     printf("Running away!\n");
	     return(0);
	   default:
	     printf("Bad input. Try again.\n");
	     break;
	 }
      } else {
         // Autopilot. Userless player acts independently.
	 Target->health = Target->health - EffectiveAttack;
	 printf("%s inflicted %d damage to %s.\n", Attacker->name, EffectiveAttack, Target->name);
	 DisplayStats(Target);
      }

      // Once turn is finished, check to see if someone has one, otherwise, swap and continue.
      if (Target->health <= 0) {
	printf("%s has bested %s in combat.\n", Attacker->name, Target->name) ;
      } else {
	 // Swap attacker and target.
	 player *tmp = Attacker;
	 Attacker = Target;
	 Target = tmp;
      }
   }

   return(0);
}

void DisplayFightMenu (void) {
  printf("1) Attack\n2) Run\n");
}

// 0 based.
enum itemNumber {
   HEALTH_POTION,
   MANA_POTION
};

typedef struct ItemStructure {
   char name[50];
   char description [100];
   int health;
   int mana;
   int quantity;
   int usesLeft;
   int id;
} item;

// Doubly linked list for items.
typedef struct itemNodeStructure {
   item *current;	                 // Pointer to current item.
   struct itemNodeStructure *previous;   // Pointer to previous item in the list.
   struct itemNodeStructure *next;	 // Pointer to the next item in the list.
} itemNode;

 itemNode *inventory;

#include <stdio.h>
#include <string.h>
#include <stdbool.h>
#include <stdlib.h>
#include "gameProperties.h"
#include "players.h"
#include "fightSys.h"

// 0 based.
enum itemNumber {
   HEALTH_POTION,
   MANA_POTION
};

typedef struct ItemStructure {
   char name[50];
   char description [100];
   int health;
   int mana;
   int quantity;
   int usesLeft;
   int id;
} item;

// Doubly linked list for items.
typedef struct itemNodeStructure {
   item *current;	                 // Pointer to current item.
   struct itemNodeStructure *previous;   // Pointer to previous item in the list.
   struct itemNodeStructure *next;	 // Pointer to the next item in the list.
} itemNode;

// Function Prototypes
int DisplayInventory(itemNode *node);
int AddItem(itemNode *inventory, enum itemNumber number);

int main () {
  player *Hero = NewPlayer(WARRIOR, "Sir Leeroy");
  player *Villain = NewPlayer(WARRIOR, "Sir Jenkins");

  AddItem(Hero->inventory, HEALTH_POTION); 
  AddItem(Hero->inventory, HEALTH_POTION); 
  AddItem(Hero->inventory, MANA_POTION);
  DisplayInventory(Hero->inventory);  

  return(0);
}

// Exampleː DisplayInventory(Player->inventory);
int DisplayInventory(itemNode *node) {
  // While there is an item present, print said item.
  while (node->current != NULL)  {
    printf("Name: %s\n", node->current->name);
    printf("Description: %s\n", node->current->description);
    printf("Health: %d\n", node->current->health);
    printf("Mana: %d\n", node->current->mana);
    printf("Uses Left: %d\n", node->current->usesLeft);
    printf("Quantity: %d\n\n", node->current->quantity);

    // If the node points to another node, go to it and print it's item. Otherwise, end loop.
    if (node->next != NULL) {
      node = node->next;   // Move to next node.
    } else {
      return(0);           // Loop ends
    }
  }
  // Inventory pointer is NULL, there are no items.
  printf("Inventory is empty.\n");
  return(0);
}

// FIND ITEM
// Used in the functionsː AddItem and RemoveItem.
// Can't return 0 because it's interpreted as an int. Return NULL for functions
// that are supposed to return pointers.
itemNode* findItem (itemNode *node, enum itemNumber number) {
  
  // If the node is NULL, it's an empty list. End function.
  if (node == NULL) {
    return(NULL);
  }

  // While the current node has an item.
  while (node->current != NULL) {
     
     // Compare that item's id to our number.
     // If it is a match, return the memory address of that node.
     if (node->current->id == number) {
       return(node);
     } 

     // If the current item doesn't match and there
     // is another node to look examine, move to it.
     if (node->next != NULL) {
       node = node->next;
     } else {
       return(NULL);   // List ends.
     }
  }
  return(NULL);  // List is empty.
}

// Use Exampleː AddItem(Hero->inventory, HEALTH_POTION);
int AddItem(itemNode *node, enum itemNumber number) {
  itemNode *previousNode;
  itemNode *searchResult;

  // See if item already exists.
  searchResult = findItem(node, number);
  if (searchResult != NULL) {
    searchResult->current->quantity += 1;    // Increase quantity by one and end function.
    return(0);
  }
  
  // Generate item if it doesn't exist.
  // This requires allocating memory and increasing
  // the size of the linked list.
  item *object = malloc(sizeof(item));          // Allocating memory for item.

  // Just like our class enumeration, our item names are variables
  // that stand for numbers. Because cases in C can't use strings,
  // this method makes them much more readable.
  switch(number) {
  case HEALTH_POTION:
    strcpy(object->name, "Health Potion");
    strcpy(object->description, "Drinkable item that heals 20 health points.");
    object->health = 20;
    object->usesLeft = 1;
    object->quantity = 1;
    object->id = number;          // ID and ItemNumber are the same.
    break;
  case MANA_POTION:
    strcpy(object->name, "Mana Potion");
    strcpy(object->description, "Drinkable item that heals 20 mana.");
    object->usesLeft = 1;
    object->quantity = 1;
    object->mana = 20;
    object->id = number;
    break;
  }

  // Now that our object has been created, we must find free space for it.

  // If the current node is unused allocate memory and assign item.
  if (node->current == NULL) {
    node->current = object;

  // If the current node is occupied, check the next node.
  // If the next node doesn't exist, then we must allocate memory
  // to the next pointer.  
  } else if (node->next == NULL) {
    node->next = malloc(sizeof(itemNode));        // Allocate memory to the next pointer.
    previousNode = node;                          // Store location of current node.
    node = node->next;                            // Move to the next node.
    node->previous = previousNode;                // Link the current node to the previous one.
    node->current = object;                       // Assign item to the current node.
  } else {
    // If current and next node are occupied, search for the last node.
    // The last node will have an empty "next" spot.
    while (node->next != NULL) {
      node = node->next;
    }

    node->next = malloc(sizeof(itemNode));        // Allocate memory to the next pointer.
    previousNode = node;                          // Store location of current node.
    node = node->next;                            // Move to the next node.
    node->previous = previousNode;                // Link the current node to the previous one.
    node->current = object;                       // Assign item to the current node.
  }
  return(0);
}

#include <stdio.h>
#include <string.h>
#include <stdbool.h>
#include <stdlib.h>

// 0 based.
enum itemNumber {
   HEALTH_POTION,
   MANA_POTION
};

typedef struct ItemStructure {
   char name[50];
   char description [100];
   int health;
   int mana;
   int quantity;
   int usesLeft;
   int id;
} item;

// Doubly linked list for items.
typedef struct itemNodeStructure {
   item *current;	 // Pointer to current item.
   struct itemNodeStructure *previous;   // Pointer to previous item in the list.
   struct itemNodeStructure *next;	 // Pointer to the next item in the list.
} itemNode;

typedef struct playerStructure {
   char name[50];
   int health;
   int mana;
   int attack;
   int defense;
   bool autoPilot;
   itemNode *inventory;
} player;

// Function Prototype
void DisplayStats(player *target);
int DisplayInventory(itemNode *node);
int AddItem(itemNode *inventory, enum itemNumber number);
int RemoveItem(itemNode *inventory, enum itemNumber number);
itemNode* findItem(itemNode *node, enum itemNumber number);

// MAIN
int main () {

  player *Hero = malloc(sizeof (player));

  // Hero
  strcpy(Hero->name, "Sir Leeroy");
  Hero->health = 60;
  Hero->mana = 30;
  Hero->attack = 5;
  Hero->defense = 1;
  Hero->autoPilot = false;
  Hero->inventory = malloc(sizeof(itemNode)); // It's necessary to initialize the inventory property with a
                                              // memory address. That way we can pass the address instead of the pointer address.
					      // Then our function would need to accept a pointer to a pointer to an itemNode
					      // as an argument and that's too much overhead.

  AddItem(Hero->inventory, HEALTH_POTION); 
  AddItem(Hero->inventory, HEALTH_POTION); 
  AddItem(Hero->inventory, MANA_POTION);
  RemoveItem(Hero->inventory, MANA_POTION);
  DisplayInventory(Hero->inventory);

  return(0);
}

int DisplayInventory(itemNode *node) {
  // While there is an item present, print said item.
  while (node->current != NULL)  {
    printf("Name: %s\n", node->current->name);
    printf("Description: %s\n", node->current->description);
    printf("Health: %d\n", node->current->health);
    printf("Mana: %d\n", node->current->mana);
    printf("Uses Left: %d\n", node->current->usesLeft);
    printf("Quantity: %d\n\n", node->current->quantity);

    // If there is another item in the list, go to it, else, stop.
    if (node->next != NULL) {
      node = node->next;
    } else {
      return(0);
    }
  }
  printf("Inventory is empty.\n");
  return(0);
}

// FIND ITEM
// Can't return 0 because it's interpreted as an int. Return NULL for functions
// that are supposed to return pointers.
itemNode* findItem (itemNode *node, enum itemNumber number) {
  if (node == NULL) {
    return(NULL);
  }

  // Avoid unitialized or unassigned nodes.
  while (node->current != NULL) {
     if (node->current->id == number) {
       return(node);
     } 

     if (node->next != NULL) {
       node = node->next;
     } else {
       return(NULL);
     }
  }
  return(NULL);
}

int AddItem(itemNode *node, enum itemNumber number) {
  itemNode *previousNode;
  itemNode *searchResult;

  // See if item already exists.
  searchResult = findItem(node, number);
  if (searchResult != NULL) {
    searchResult->current->quantity += 1;
    return(0);
  }
  
  // Generate item if it doesn't exist.
  item *object = malloc(sizeof(item)); // Item.
  switch(number) {
  case 0:
    strcpy(object->name, "Health Potion");
    strcpy(object->description, "Drinkable item that heals 20 health points.");
    object->health = 20;
    object->usesLeft = 1;
    object->quantity = 1;
    object->id = number;
    break;
  case 1:
    strcpy(object->name, "Mana Potion");
    strcpy(object->description, "Drinkable item that heals 20 mana.");
    object->usesLeft = 1;
    object->quantity = 1;
    object->mana = 20;
    object->id = number;
    break;
  }

  // If node is unused allocate memory and assign item.
  if (node->current == NULL) {
    node->current = object;
  // If node is occupied, check next node.
  } else if (node->next == NULL) {
    node->next = malloc(sizeof(itemNode));
    previousNode = node;
    node = node->next;
    node->previous = previousNode;
    node->current = object;
  // If current and next node are occupied, search for the last node.
  // The last node will have an empty "next" spot.
  } else {
    while (node->next != NULL) {
      node = node->next;
    }

    node->next = malloc(sizeof(itemNode));
    previousNode = node;
    node = node->next;
    node->previous = previousNode;
    node->current = object;
  }
  return(0);
}

int RemoveItem(itemNode *node, enum itemNumber number) {
  itemNode *searchResult;
  itemNode *previous;
  itemNode *next;

  // See if item already exists.
  searchResult = findItem(node, number);

  // If item exists, and reduce quantity by 1.
  if (searchResult != NULL) {
    searchResult->current->quantity -= 1;

    // If reduction results in 0 quantity, remove item entirely.
    if (searchResult->current->quantity <= 0) {
      previous = searchResult->previous;
      next = searchResult->next;

      // Free the item and then the node containing it.
      free(searchResult->current);
      free(searchResult);

      // Switch linked list together.
      // We can't assign the next/previous members if the itemNode is null.
      if (previous != NULL) {
        searchResult = previous;
        searchResult->next = next;
      }
      if (next != NULL) {
        searchResult = next;
	searchResult->previous = previous;
      }
    }
  }  
  return(0);
}