#include "net/netstack.h"
#include "net/nullnet/nullnet.h"
#include <stdio.h>
#include <string.h>
#include "sys/log.h"
#define LOG_MODULE "App"
#define LOG_LEVEL LOG_LEVEL_INFO

#include "os/dev/serial-line.h"
#include "arch/cpu/cc26x0-cc13x0/dev/cc26xx-uart.h"

#include <stdlib.h>



#define MAX_CUSTOMERS 20

enum message_type{CASH_OUT_MSG, PRODUCT_MSG, ITEM_ELEM_MSG, BASKET_MSG, START_OF_LIST_PRODUCTS_MSG};

typedef struct basket_msg
{
	uint8_t n_products;
	uint8_t customer_id;
	linkaddr_t* address;
	
	
}basket_msg;

typedef struct user_invoice
{
	uint8_t n_prods;
	float total_sum;
	uint8_t customer_id;
	linkaddr_t* address_basket;
	uint8_t empty;
	
	
}user_invoice;

typedef struct cash_out_msg
{
	uint8_t customer_id;
}cash_out_msg;

typedef struct product_msg{
	
	uint8_t customer_id;
	uint8_t product_id;
	float prize;

}product_msg;

typedef struct msg{
	enum message_type msg_type;
	cash_out_msg cash_out;
	product_msg product;
	basket_msg basket;
	
	
    
}msg;

PROCESS(cassa_main_process, "Cassa process");
AUTOSTART_PROCESSES(&cassa_main_process);

static uint8_t invoice_index(uint32_t customer_id, user_invoice invoices[]) 
{

	uint8_t i = 0;
	for(i = 0; i< MAX_CUSTOMERS;i++) {
		if (invoices[i].empty==0 && customer_id == invoices[i].customer_id) 
				return i;
			
	}
	return -1;

}

static uint8_t index_free_spot(user_invoice invoices[])
{
	uint8_t i = 0;
	for(i = 0;i<MAX_CUSTOMERS;i++) {
		if (invoices[i].empty == 1) {
			return i;
		}

	}
	return -1;

}

static void input_callback(const void* data, uint16_t len, const linkaddr_t* source_address, const linkaddr_t* destination_address) 
{
	msg received_msg;
		
	static user_invoice invoices[MAX_CUSTOMERS];
	
	
	if (len == sizeof(*data)) {
		memcpy (&received_msg, data, sizeof ((msg *)data));
		LOG_INFO("Received data");
		LOG_INFO_LLADDR(source_address);	//this is the link layer address
		LOG_INFO("\n");
		//we need to receive an additional message to start the process of receiving the products because if we start receiving the products immediately 
		//in the case of parallel processes we wouldnt know to what client and what basket that product is assosiated with
		if (received_msg.msg_type == BASKET_MSG) {
			uint8_t index = index_free_spot(invoices);
			if (index != -1 ) {
				invoices[index].n_prods = received_msg.basket.n_products;
				invoices[index].total_sum = 0;
				invoices[index].customer_id = received_msg.basket.customer_id;
				invoices[index].address_basket = received_msg.basket.address;
				
				msg start_sending_list;
				start_sending_list.msg_type = START_OF_LIST_PRODUCTS_MSG;
				nullnet_buf = (uint8_t*)&start_sending_list;
				
				LOG_INFO("Sending acknowledgment to start sending list of products");
				LOG_INFO_("\n");
				nullnet_len = sizeof(start_sending_list);
				NETSTACK_NETWORK.output((invoices[index].address_basket));
				


			} else
			printf("Reached max number of customers");
		}
		if (received_msg.msg_type == PRODUCT_MSG) {
			uint8_t index = invoice_index(received_msg.product.customer_id, invoices);
			if (index != -1) {
				if (invoices[index].n_prods > 0) {			
					invoices[index].total_sum += received_msg.product.prize;
					invoices[index].n_prods--;
				}
				if (invoices[index].n_prods == 0) {
					printf("Total sum for client %d is %f\n", (int)invoices[index].customer_id, invoices[index].total_sum);
					invoices[index].empty = 1;
				}
			}else
			printf("Customer with that id is not associated to any basket!");
		}
	}
}

PROCESS_THREAD(cassa_main_process, ev, data) {
	PROCESS_BEGIN();

	static uint8_t customer_id;
	static msg bro_customer_id;
	
	cc26xx_uart_set_input(serial_line_input_byte);
	serial_line_init();

	nullnet_buf = (uint8_t*)&bro_customer_id;
	nullnet_set_input_callback(input_callback);	//this should be moved down?
	
	
	printf("Dear customer, insert your card id\n");

	while (true) {
		PROCESS_WAIT_EVENT_UNTIL(ev == serial_line_event_message);

		printf("Customer's id: %s\n", (char*)data);
		customer_id = atoi(data);
		printf("id: %d\n", (int)customer_id);

		bro_customer_id.msg_type = CASH_OUT_MSG;
		bro_customer_id.cash_out.customer_id = customer_id; 

		LOG_INFO("Sending BROADCAST customer id: %d\n", (int)customer_id);
		LOG_INFO_LLADDR(NULL);
		LOG_INFO_("\n");
		nullnet_len = sizeof(bro_customer_id);
		NETSTACK_NETWORK.output(NULL);
	}

	PROCESS_END();
}