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

#include <stdint.h>

#include <arpa/inet.h>

#include "message.h"
#include "usocket.h"

// #define IPC_WITH_ERRORS 3

uint32_t ipc_message_raw_serialize (char *buffer, char type, char user_type, char *message, uint32_t message_size)
{
	uint32_t msize = 6 + message_size;
	buffer[0] = type;

	uint32_t msize_n = htonl (message_size);
	uint32_t index = 1;

	memcpy (buffer + index, &msize_n, sizeof (uint32_t));
	index += sizeof (uint32_t);
	buffer[index] = user_type;
	index += 1;
	memcpy (buffer + index, message, message_size);

	return msize;
}

struct ipc_error ipc_message_format_read (struct ipc_message *m, const char *buf, size_t msize)
{
	T_R ((m == NULL), IPC_ERROR_MESSAGE_FORMAT_READ__EMPTY_MESSAGE);
	T_R ((buf == NULL), IPC_ERROR_MESSAGE_FORMAT_READ__EMPTY_BUFFER);
	T_R ((msize > IPC_MAX_MESSAGE_SIZE), IPC_ERROR_MESSAGE_FORMAT_READ__PARAM_MESSAGE_SIZE);

	// message format:
	//   Type (1 B) | Length (4 B) | UserType (1 B) | Payload (Length B)
	m->type = buf[0];
	uint32_t unformated_size = 0;
	memcpy (&unformated_size, buf + 1, sizeof (uint32_t));
	m->length = ntohl (unformated_size);
	m->user_type = buf[1 + sizeof m->length];

	T_R ((m->length > IPC_MAX_MESSAGE_SIZE), IPC_ERROR_MESSAGE_FORMAT_READ__MESSAGE_TOO_LONG);
#if defined(IPC_WITH_ERRORS) && IPC_WITH_ERRORS > 2
	LOG_INFO ("receiving msg: type %d, paylen %u, total %lu", m->type, m->length, msize);
#endif
	T_R ((m->length != msize - IPC_HEADER_SIZE && m->length != 0)
		, IPC_ERROR_MESSAGE_FORMAT_READ__READ_MESSAGE_SIZE);

	if (m->payload != NULL) {
		free (m->payload);
		m->payload = NULL;
	}

	if (m->length > 0) {
		m->payload = malloc (m->length);
		memcpy (m->payload, buf + IPC_HEADER_SIZE, m->length);
	} else {
		m->payload = malloc (1);
	}

	IPC_RETURN_NO_ERROR;
}

struct ipc_error ipc_message_format_write (const struct ipc_message *m, char **buf, size_t * msize)
{
	T_R ((m == NULL), IPC_ERROR_MESSAGE_FORMAT_WRITE__EMPTY_MESSAGE);
	T_R ((buf == NULL), IPC_ERROR_MESSAGE_FORMAT_WRITE__EMPTY_BUFFER);
	T_R ((msize == NULL), IPC_ERROR_MESSAGE_FORMAT_WRITE__EMPTY_MSIZE);
	T_R ((m->length > IPC_MAX_MESSAGE_SIZE), IPC_ERROR_MESSAGE_FORMAT_WRITE__MESSAGE_LENGTH);

	if (*buf == NULL) {
		*buf = malloc (IPC_HEADER_SIZE + m->length);
		memset (*buf, 0, IPC_HEADER_SIZE + m->length);
	}

	char *buffer = *buf;
	uint32_t net_paylen = htonl (m->length);

	buffer[0] = m->type;
	memcpy (buffer + 1, &net_paylen, sizeof (uint32_t));
	buffer[1 + sizeof m->length] = m->user_type;
	if (m->payload != NULL && m->length > 0) {
		memcpy (buffer + IPC_HEADER_SIZE, m->payload, m->length);
	}

	*msize = IPC_HEADER_SIZE + m->length;

#if defined(IPC_WITH_ERRORS) && IPC_WITH_ERRORS > 2
	LOG_INFO ("sending msg: type %u, paylen %u, msize %lu", m->type, m->length, *msize);
#endif

	IPC_RETURN_NO_ERROR;
}

// MSG FORMAT

struct ipc_error ipc_message_format (struct ipc_message *m, char type, char utype, const char *payload, size_t length)
{
	T_R ((m == NULL), IPC_ERROR_MESSAGE_FORMAT__NO_MESSAGE_PARAM);
	T_R ((length > IPC_MAX_MESSAGE_SIZE), IPC_ERROR_MESSAGE_FORMAT__MESSAGE_SIZE);
	T_R (((length == 0 && payload != NULL) || (length > 0 && payload == NULL))
		, IPC_ERROR_MESSAGE_FORMAT__INCONSISTENT_PARAMS);

	m->type = type;
	m->user_type = utype;
	m->length = (uint32_t) length;

	if (payload != NULL) {
		if (m->payload != NULL) {
			free (m->payload);
		}

		SECURE_BUFFER_HEAP_ALLOCATION_R (m->payload, length,, IPC_ERROR_MESSAGE_FORMAT__HEAP_ALLOCATION);
	}

	if (payload != NULL) {
		memcpy (m->payload, payload, length);
	}
	IPC_RETURN_NO_ERROR;
}

struct ipc_error ipc_message_format_data (struct ipc_message *m, char utype, const char *payload, size_t length)
{
	return ipc_message_format (m, MSG_TYPE_DATA, utype, payload, length);
}

struct ipc_error ipc_message_format_server_close (struct ipc_message *m)
{
	return ipc_message_format (m, MSG_TYPE_SERVER_CLOSE, 0, NULL, 0);
}

struct ipc_error ipc_message_empty (struct ipc_message *m)
{
	T_R ((m == NULL), IPC_ERROR_MESSAGE_EMPTY__EMPTY_MESSAGE_LIST);

	if (m->payload != NULL) {
		free (m->payload);
		m->payload = NULL;
	}

	m->length = 0;

	IPC_RETURN_NO_ERROR;
}

// store and remove only pointers on allocated structures
struct ipc_error ipc_messages_add  (struct ipc_messages *messages, const struct ipc_message *message)
{
	T_R ((messages == NULL), IPC_ERROR_ADD_MESSAGE_TO_SEND__NO_PARAM_MESSAGES);
	T_R ((message  == NULL), IPC_ERROR_ADD_MESSAGE_TO_SEND__NO_PARAM_MESSAGE);

	messages->size++;
	if (messages->size == 1 && messages->messages == NULL) {
		// first allocation
		SECURE_BUFFER_HEAP_ALLOCATION_R (messages->messages, sizeof (struct ipc_message),,
						IPC_ERROR_ADD_MESSAGE_TO_SEND__MALLOC);
	} else {
		messages->messages = realloc (messages->messages, sizeof (struct ipc_message) * messages->size);
	}

	T_R ((messages->messages == NULL), IPC_ERROR_ADD_MESSAGE_TO_SEND__EMPTY_LIST);

	// DEEP COPY.
	messages->messages[messages->size -1] = *message;
	if (message->length > 0 && message->payload != NULL) {
		messages->messages[messages->size -1].payload = malloc(message->length * sizeof (char));
		strncpy(messages->messages[messages->size -1].payload, message->payload, message->length);
	}
	else {
		messages->messages[messages->size -1].payload = NULL;
	}

	IPC_RETURN_NO_ERROR;
}

// Remove only pointers on allocated structures.
struct ipc_error ipc_messages_del  (struct ipc_messages *messages, uint32_t index)
{
	T_R ((messages == NULL), IPC_ERROR_DEL_MESSAGE_TO_SEND__NO_PARAM_MESSAGES);
	T_R ((messages->size == 0 || index >= messages->size), IPC_ERROR_MESSAGE_DEL__INDEX_ERROR);

	// NOT A DEEP COPY.
	messages->size--;
	if (messages->size == 0) {
		free (messages->messages);
		messages->messages = NULL;
	}
	else {
		messages->messages[index] = messages->messages[messages->size];
		messages->messages = realloc (messages->messages, sizeof (struct ipc_message) * messages->size);
		T_R ((messages->messages == NULL), IPC_ERROR_MESSAGE_DEL__EMPTY_LIST);
	}

	IPC_RETURN_NO_ERROR;
}

void ipc_messages_free (struct ipc_messages *messages)
{
	if (messages != NULL)
	{
		if (messages->messages != NULL)
		{
			free(messages->messages);
			messages->messages = 0;
		}
	}
}