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#pragma once
#include <stdint.h>
#include <stdbool.h>
#include "bin.h"
#define WS_PROTOCOL_CMD_MAX_ARGUMENTS (3)
#define WS_PROTOCOL_CMD_BUFFER_LEN (40)
#define WS_PROTOCOL_CMD_AMOUNT (1)
#define WS_PROTOCOL_C_EOL (0x0a)
#define WS_PROTOCOL_C_SPACE (0x20)
#define WS_PROTOCOL_C_NULL (0x00)
/**
* @brief parsed request cmd struct, holds arguments similar to argc and argv
* provided to `int main()`
*/
typedef struct {
int argc; /** argument count */
char* argv[]; /** argument array, null terminated strings */
} ws_s_protocol_parsed_req_cmd;
/**
* @brief holds parser state variables for `ws_protocol_parse_req_byte` function.
* each incoming tcp request should get it's own parser 'instance'
*/
typedef struct {
ws_s_protocol_parsed_req_cmd* target; /** parsed cmd reference */
bool valid; /** command still valid flag */
char* cmd; /** raw cmd */
uint16_t cmd_len; /** raw cmd string length */
uint16_t arg_len; /** amount of arguments */
uint16_t args_len[]; /** array of argument lengths */
} ws_s_protocol_req_parser_state;
/** @brief return values for command handlers */
typedef enum {
WS_PROTOCOL_CMD_RETURN_OK = 0,
WS_PROTOCOL_CMD_RETURN_ERROR = 1,
} ws_e_protocol_cmd_return_value;
/** @brief cmd codes (used to call handlers) */
typedef enum {
WS_PROTOCOL_CMD_UNKNOWN = -1,
WS_PROTOCOL_CMD_LAST_RECORDS = 0,
} ws_e_protocol_cmd;
/** @brief request response data struct */
typedef struct {
ws_e_protocol_cmd_return_value success; /** status code for response
validity, defaults to
WS_PROTOCOL_CMD_RETURN_ERROR */
bool csh; /** whether the response handler has logic for a custom send
handler, false by default */
ws_s_bin* msg; /** pointer to response data, uninitialized by default */
ws_e_protocol_cmd cmd_code; /** cmd code */
} ws_s_protocol_res;
/**
* @brief allocate parser struct
*
* @return pointer to newly allocated struct
*/
ws_s_protocol_req_parser_state* ws_protocol_req_parser_alloc();
/** @brief deallocate parser struct, automatically frees all child pointers */
void ws_protocol_req_parser_free(ws_s_protocol_req_parser_state* state);
/** @brief reset parser state to parse a new request */
void ws_protocol_req_parser_reset(ws_s_protocol_req_parser_state* state);
/**
* @brief initialize ws_s_protocol_parsed_req_cmd struct pointer of
* ws_s_protocol_req_parser_state (internal only)
*/
void ws_protocol_req_cmd_init(ws_s_protocol_req_parser_state* state);
/** @brief deallocate ws_s_protocol_parsed_req_cmd struct pointer (internal only) */
void ws_protocol_req_cmd_free(ws_s_protocol_parsed_req_cmd* cmd);
/**
* @brief parse incoming data byte by byte until a finished command is detected
*
* @param state parser state object, each incoming request should have it's own parser state
* @param input input byte
*/
void ws_protocol_parse_req_byte(ws_s_protocol_req_parser_state* state, char input);
/**
* @brief parse incoming data chunk
*
* @param state parser state object, each incoming request should have it's own parser state
* @param input input byte array
* @param length input byte array length
*/
void ws_protocol_parse_req_bytes(ws_s_protocol_req_parser_state* state, char* input, unsigned int length);
/**
* @brief handle complete command
*
* this function gets called when ws_protocol_parse_req_byte(s) has detected a
* finished command. this function decides which command handler gets called,
* given that argv[0] contains a valid command. command argument parsing is
* handled by the command handler function.
*
* @return response
*
* @param parsed_cmd cmd parsed into ws_s_protocol_parsed_req_cmd struct
*/
ws_s_protocol_res* ws_protocol_parse_req_finished(ws_s_protocol_parsed_req_cmd* parsed_cmd);
/**
* @brief create a `last-records` request command
* @return ws_s_bin containing the command string
*/
ws_s_bin* ws_protocol_req_last_records(unsigned int record_amount);
/**
* @brief response handler
*
* gets fired when the weather station receives a complete command, and returns
* a response struct with a success code and an optional message. if
* response->csh is set to `true` within the handler, it gets fired a second
* time after the response header is sent, but with the `send` parameter set to
* `true`. this is so response handlers can send large amounts of data without
* allocating large areas of memory.
*
* @param parsed_cmd complete parsed command from ws_protocol_parse_req_*
* @param response response struct with uninitialized pointer to msg
* @param send `false` on first run, `true` on second run if `response->csh` was set to true
*/
typedef void ws_protocol_res_handler_t(ws_s_protocol_parsed_req_cmd*, ws_s_protocol_res*, bool);
ws_protocol_res_handler_t ws_protocol_res_last_records;
/**
* @brief data sender wrapper
*
* this function should be implemented in the source files of each target
* platform, as the send interface will be different on desktop and on the
* stm32.
*
* @param data pointer to data char array
* @param length length of data array
*/
void ws_protocol_send_data(const char* data, unsigned int length);
/** @brief response handlers, called when a command is parsed */
static ws_protocol_res_handler_t* g_ws_protocol_res_handlers[WS_PROTOCOL_CMD_AMOUNT] = {
[WS_PROTOCOL_CMD_LAST_RECORDS] = &ws_protocol_res_last_records,
};
/** @brief return length of custom protocol header */
unsigned short ws_protocol_get_header_size(ws_s_protocol_res* response);
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