#include "callback_http.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "../utils/strings.h"
#include "http_headers.h"
#include "request_method.h"
#include "response_code.h"

static const char* SEPS = " \n\r";
#define return_bad_request() {                     \
		args->output = "HTTP/1.1 400 Bad Request"; \
		args->output_size = 24;                    \
		return;                                    \
	}

static void append_header(enum HttpHeader header, const char* value, const char** parts_array, size_t *ind);

void callback_http(callback_args* args) {
	if (args->extra == NULL) {
		printf("No HTTP callbacks were set!");
		return;
	}

	http_callbacks *callbacks = args->extra;

	/* Parse input request */

	client_message in_message = {
		.method  = RM_UNKNOWN,
		.url     = NULL,
		.version = NULL,
		.headers = { 0 },
	};

	/** Request method **/

	char* word = strtok(args->input, SEPS);
	if (word == NULL) return_bad_request()

	for (enum RequestMethod rm = RM_GET; rm < RM_UNKNOWN; rm++) {
		if (streq(REQUEST_METHOD_NAME[rm], word)) {
			in_message.method = rm;
			break;
		}
	}

	if (in_message.method == RM_UNKNOWN)
		return_bad_request()

	/** URL **/

	word = strtok(NULL, SEPS);
	if (word == NULL) return_bad_request()

	in_message.url = word;

	/** HTTP version **/

	word = strtok(NULL, SEPS);
	if (word == NULL || !streq("HTTP/1.1", word))
		return_bad_request()

	in_message.version = word;

	/** Headers **/

	word = strtok(NULL, ":\n\r");

	while(word != NULL) {
		enum HttpHeader he = 0;

		while (he < HE_LENGTH) {
			if (streq(HTTP_HEADER_NAME[he], word))
				break;
			++he;
		}
		word = strtok(NULL, "\n\r");

		if (word == NULL) break;

		if (he < HE_LENGTH) {
			while (*word == ' ') ++word;
			in_message.headers[he] = word;
		}

		word = strtok(NULL, ":\n\r");
	}

	/* Respond to request */

	response_message out_message = {
		.response_code = RC_500_INTERNAL_SERVER_ERRROR,

		.headers = { 0 },

		.body = NULL,
		.body_size = 0,
		.free_body = 0,
	};

	if (in_message.method < RM_UNKNOWN)
		callbacks->all_callbacks[in_message.method](&in_message, &out_message);
	else
		printf("Unsupported method!");

	const char* response[1024] = { 0 };
	size_t rind = 0;

	response[rind++] = "HTTP/1.1 ";
	response[rind++] = RESPONSE_CODE_NAME[out_message.response_code];
	response[rind++] = "\n";

	for (enum HttpHeader he = 0; he < HE_LENGTH; he++) {
		if (out_message.headers[he] != NULL)
			append_header(he, out_message.headers[he], response, &rind);
	}

	response[rind++] = "\n";

	if (out_message.body != NULL && out_message.body_size > 0)
		response[rind++] = out_message.body;

	args->output      = concat_array(response, rind, &args->output_size);
	args->free_output = 1;

	if (out_message.free_body)
		free(out_message.body);
}

static void append_header(enum HttpHeader header, const char* value, const char** parts_array, size_t *ind) {
	parts_array[(*ind)++] = HTTP_HEADER_NAME[header];
	parts_array[(*ind)++] = ": ";
	parts_array[(*ind)++] = value;
	parts_array[(*ind)++] = "\n";
}