//include std lib if they havent been included
#ifndef STD_LIB_H
#define STD_LIB_H
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<stdbool.h>
#include<math.h>
#include<time.h>
#include<ctype.h>
#endif

#ifndef MENU_H
#define MENU_H
#include "menu.h"
#endif //MENU_H

//list of functions
void inv_control();
void tran_control();
void user_control();
void admin_control();
struct user_row *prompt_user();
int admin_menu_user_choices(char* name,char* role);

void admin_menu(){
    system("cls");
    welcome_message();
    //the selection menu
    // if(login valid)
    struct user_row *user = prompt_user();
    if(user == NULL){//invalid user
        return;
    }
    int choice = 0;
    do
    {
        choice = admin_menu_user_choices(user->name,user->role);
        switch (choice)
        {
            case 1://action with inventory
                inv_control();
                break;
            case 2://action with transction
                // tran_control();
                break;
            case 3://action with user
                // user_control();
                break;
            case 4://action with admin user register
                // admin_control();
                break;
            case 5://Exit
                break;
            default://invalid input ,should not happen,as it is already catch in above function
                printf("Invalid choice\n");
                break;
        }
    }while(choice != 5);
    
    
    return;
}

//func for main for admin
struct user_row *prompt_user(){
    long user_id = 0;
    printf("Please tap your card(student card, staff card,etc)(or input the id)(0 to cancel)\n>");
    scanf("%ld", &user_id);
    if(user_id == 0){
        printf("cancelled\n");
        printf("press any key to continue\n");
        fflush(stdin);
        getchar();
        return NULL;
    }
    struct user_row *user = get_user(user_id);
    if(user == NULL){
        printf("User not found\n");
        printf("press any key to continue\n");
        fflush(stdin);
        getchar();
        return NULL;
    }else if(!is_admin(user->role)){
        printf("You aren't an admin\n");
        printf("press any key to continue\n");
        fflush(stdin);
        getchar();
        return NULL;
    }else{
        printf("Welcome %s(%s)\n", user->name,user->role);
        printf("press any key to continue\n");
        fflush(stdin);
        getchar();
    }
    return user;
}

int admin_menu_user_choices(char* name,char* role){
    int choice = 0;
    do{
        system("cls");
        printf("Welcome %s(%s)\n", name,role);
        printf("Please select an option:\n");
        printf("1. Inventory control\n");
        printf("2. Transaction control\n");
        printf("3. User control\n");
        printf("4. Admin user register\n");
        printf("5. Exit and Logout\n");
        printf(">");
        scanf("%d", &choice);
        if(choice < 1 || choice > 5){
            printf("Invalid choice...press any key to retry....\n");
            fflush(stdin);
            getchar();
        }
    }while(choice < 1 || choice > 5);
    return choice;
}

//invetory control
void add_item();
void remove_item(struct inventory db,int index);
void update_item(struct inventory db,int index);
void admin_list_pages(struct inventory db);
void item_control(struct inventory db,int index);

int prompt_inv_control(){
    int choice = 0;
    do{
        system("cls");
        printf("Please select an option:\n");
        printf("1. List(allow all operation include add)\n");
        printf("2. Add item(shortcut to add item)\n");
        printf("3. Exit\n");
        printf(">");
        scanf("%d", &choice);
        if(choice < 1 || choice > 3){
            printf("Invalid choice...press any key to retry....\n");
            fflush(stdin);
            getchar();
        }
    }while(choice < 1 || choice > 3);
    return choice;
}

void inv_control(){
        struct inventory db = read_db_invt();
        int choice = 0;
        do{
        choice = prompt_inv_control();
        switch (choice){
            case 1://list
                //add a new element with product name new item
                //for item control
                db.row = (struct inventory_row *)realloc(db.row, sizeof(struct inventory_row) * (db.db.row_count + 1));
                db.db.row_count += 1;
                strcpy(db.row[db.db.row_count - 1].product,"CREATE NEW ITEM");
                db.row[db.db.row_count - 1].barcode = -1024;//IMPORTANT: -1024 is reserved for new item
                list_page(db,NULL,db.db.row_count,item_control);
                break;
            case 2://add item
                add_item();
                break;
            case 3://exit
                break;
            default://should not happen
                printf("Invalid choice\n");
                break;
        }
        }while(choice != 3);
}

void show_item_admin(struct inventory db,int index){
    system("cls");
    printf("Product: %s\n", db.row[index].product);
    printf("Catergory: %s\n", db.row[index].category);
    printf("Brand: %s\n", db.row[index].brand);
    printf("Price: $%lf\n", db.row[index].price);
    printf("Stock: %d\n", db.row[index].stock);
    printf("Barcode: %ld\n",db.row[index].barcode);
    getchar();
    return;
}

void item_control(struct inventory db,int index){
    int choice = 0;
    if(db.row[index].barcode == -1024){//new item
        add_item();
        return;
    }
    do
    {
        system("cls");
        show_item_admin(db,index);
        printf("Operations\n");
        printf("0 exit\n");
        printf("1 update item\n");
        printf("2 remove item\n");
        printf("Enter your choice: ");
        fflush(stdin);
        scanf("%d", &choice);
        switch (choice)
        {
            case 1:
                update_item(db,index);
                break;
            case 2:
                remove_item(db,index);
                break;
            default:
                break;
        }
    } while (choice != 0);
}

char* prompt_item(char* prompt){
    char* item = malloc(sizeof(char) * 100);
    do{
        printf("%s",prompt);
        fflush(stdin);
        scanf("%[^\n]",item);
        if(strcmp(item,"") == 0){
            printf("Invalid input, try again?(y/n)\n");
            fflush(stdin);
            char c = getchar(); 
            if(c == 'n'){
                return NULL;
            }
        }
    }while(strcmp(item,"") == 0);
    return item;
}

void add_item(){
    char* temp;
    system("cls");
    printf("Add new item\n");
    struct inventory_row *item = (struct inventory_row *)malloc(sizeof(struct inventory_row));
    temp = prompt_item("Please input the name: \n>");
    if(temp == NULL){
        free(item);
        return;
    }
    strcpy(item->product,temp);
    temp = prompt_item("Please input the brand: \n>");
    if(temp == NULL){
        free(item);
        return;
    }
    strcpy(item->brand,temp);
    temp = prompt_item("Please input the category: \n>");
    if(temp == NULL){
        free(item);
        return;
    }
    strcpy(item->category,temp);
    temp = prompt_item("Please input the price: \n>");
    if(temp == NULL){
        free(item);
        return;
    }
    item->price = atof(temp);
    temp = prompt_item("Please input the stock: \n>");
    if(temp == NULL){
        free(item);
        return;
    }
    item->stock = atoi(temp);
    temp = prompt_item("Please input the barcode: \n>");
    if(temp == NULL){
        free(item);
        return;
    }
    item->barcode = atol(temp);
    if(item == NULL || !append_inventory(item)){
        printf("Failed to add item\n");
    }else{
        printf("Item added\n");
    }
    printf("press any key to continue\n");
    fflush(stdin);
    getchar();
}

void update_item(struct inventory db,int index){
    char temp[100];
    printf("Update item(empty value to not change the value)\n");
    
    printf("Please input the name(original:%s)\n>",db.row[index].product);
    fflush(stdin);
    scanf("%[^\n]", temp);//input until /n
    if(strcmp(temp,"") != 0){//check if temp is not empty
        strcpy(db.row[index].product,temp);//if yes, copy temp to product
    }//else preserve the original value
    
    printf("Please input the brand(orginal:%s)\n>",db.row[index].brand);
    fflush(stdin);
    scanf("%[^\n]", temp);
    if(strcmp(temp,"") != 0){
        strcpy(db.row[index].brand,temp);
    }
    
    printf("Please input the category(orginal:%s)\n>",db.row[index].category);
    fflush(stdin);
    scanf("%[^\n]", temp);
    if(strcmp(temp,"") != 0){
        strcpy(db.row[index].category,temp);
    }
    
    printf("Please input the price(orginal:$%.1lf)\n>",db.row[index].price);
    fflush(stdin);
    scanf("%[^\n]", temp);
    if(strcmp(temp,"") != 0){
        db.row[index].price = atof(temp);
    }
    
    printf("Please input the stock(orginal:%d)\n>",db.row[index].stock);
    fflush(stdin);
    scanf("%[^\n]", temp);
    if(strcmp(temp,"") != 0){
        db.row[index].stock = atoi(temp);
    }

    printf("Please input the barcode(original:%ld)\n>",db.row[index].barcode);
    fflush(stdin);
    scanf("%[^\n]", temp);
    if(strcmp(temp,"") != 0){
        db.row[index].barcode = atol(temp);
    }


    if(!update_db_invt(db)){
        printf("Failed to update item\n");
    }else{
        printf("Item updated\n");
    }
    printf("press any key to continue\n");
    fflush(stdin);
    getchar();
}

void remove_item(struct inventory db,int index){
    printf("Remove item\n");
    printf("Are you sure you want to remove this item? (y/n)\n");
    char choice;
    fflush(stdin);
    scanf("%c", &choice);
    db.row[index].isdeleted = true;
    if(choice == 'y'){
        if(!update_db_invt(db)){
            printf("Failed to remove item\n");
        }else{
            printf("Item removed\n");
        }
    }else{
        printf("Item not removed\n");
    }
    printf("press any key to continue\n");
    fflush(stdin);
    getchar();
}