Momentum-Apps/flipper_http.h

// flipper_http.h
#ifndef FLIPPER_HTTP_H
#define FLIPPER_HTTP_H

#include <furi.h>
#include <furi_hal.h>
#include <furi_hal_gpio.h>
#include <furi_hal_serial.h>
#include <storage/storage.h>

// STORAGE_EXT_PATH_PREFIX is defined in the Furi SDK as /ext

#define HTTP_TAG "WebCrawler"             // change this to your app name
#define http_tag "web_crawler_app"        // change this to your app id
#define UART_CH (FuriHalSerialIdUsart)    // UART channel
#define TIMEOUT_DURATION_TICKS (2 * 1000) // 2 seconds
#define BAUDRATE (115200)                 // UART baudrate
#define RX_BUF_SIZE 1024                  // UART RX buffer size

// Forward declaration for callback
typedef void (*FlipperHTTP_Callback)(const char *line, void *context);

// Functions
bool flipper_http_init(FlipperHTTP_Callback callback, void *context);
void flipper_http_deinit();
//---
void flipper_http_rx_callback(const char *line, void *context);
bool flipper_http_send_data(const char *data);
//---
bool flipper_http_connect_wifi();
bool flipper_http_disconnect_wifi();
bool flipper_http_ping();
bool flipper_http_save_wifi(const char *ssid, const char *password);
//---
bool flipper_http_get_request(const char *url);
//---
bool flipper_http_save_received_data(size_t bytes_received, const char line_buffer[]);

// Define GPIO pins for UART
GpioPin test_pins[2] = {
    {.port = GPIOA, .pin = LL_GPIO_PIN_7}, // USART1_RX
    {.port = GPIOA, .pin = LL_GPIO_PIN_6}  // USART1_TX
};

// State variable to track the UART state
typedef enum
{
    INACTIVE,  // Inactive state
    IDLE,      // Default state
    RECEIVING, // Receiving data
    SENDING,   // Sending data
    ISSUE,     // Issue with connection
} SerialState;

// Event Flags for UART Worker Thread
typedef enum
{
    WorkerEvtStop = (1 << 0),
    WorkerEvtRxDone = (1 << 1),
} WorkerEvtFlags;

// FlipperHTTP Structure
typedef struct
{
    FuriStreamBuffer *flipper_http_stream;  // Stream buffer for UART communication
    FuriHalSerialHandle *serial_handle;     // Serial handle for UART communication
    FuriThread *rx_thread;                  // Worker thread for UART
    uint8_t rx_buf[RX_BUF_SIZE];            // Buffer for received data
    FuriThreadId rx_thread_id;              // Worker thread ID
    FlipperHTTP_Callback handle_rx_line_cb; // Callback for received lines
    void *callback_context;                 // Context for the callback
    SerialState state;                      // State of the UART

    // variable to store the last received data from the UART
    char *last_response;

    // Timer-related members
    FuriTimer *get_timeout_timer; // Timer for GET request timeout
    bool started_receiving;       // Indicates if a GET request has started
    bool just_started;            // Indicates if data reception has just started
    char *received_data;          // Buffer to store received data
} FlipperHTTP;

// Declare uart as extern to prevent multiple definitions
FlipperHTTP fhttp;

typedef struct
{
    char *key;
    char *value;
} FlipperHTTPHeader;

// Timer callback function
/**
 * @brief      Callback function for the GET timeout timer.
 * @return     0
 * @param      context   The context to pass to the callback.
 * @note       This function will be called when the GET request times out.
 */
void get_timeout_timer_callback(void *context)
{
    UNUSED(context);
    FURI_LOG_E(HTTP_TAG, "Timeout reached: 2 seconds without receiving [GET/END]...");

    // Reset the state
    fhttp.started_receiving = false;

    // Free received data if any
    if (fhttp.received_data)
    {
        free(fhttp.received_data);
        fhttp.received_data = NULL;
    }

    // Update UART state
    fhttp.state = ISSUE;
}

// UART RX Handler Callback (Interrupt Context)
/**
 * @brief      A private callback function to handle received data asynchronously.
 * @return     void
 * @param      handle    The UART handle.
 * @param      event     The event type.
 * @param      context   The context to pass to the callback.
 * @note       This function will handle received data asynchronously via the callback.
 */
static void _flipper_http_rx_callback(FuriHalSerialHandle *handle, FuriHalSerialRxEvent event, void *context)
{
    UNUSED(context);
    if (event == FuriHalSerialRxEventData)
    {
        uint8_t data = furi_hal_serial_async_rx(handle);
        furi_stream_buffer_send(fhttp.flipper_http_stream, &data, 1, 0);
        furi_thread_flags_set(fhttp.rx_thread_id, WorkerEvtRxDone);
    }
}

// UART worker thread
/**
 * @brief      Worker thread to handle UART data asynchronously.
 * @return     0
 * @param      context   The context to pass to the callback.
 * @note       This function will handle received data asynchronously via the callback.
 */
static int32_t flipper_http_worker(void *context)
{
    UNUSED(context);
    size_t rx_line_pos = 0;
    char rx_line_buffer[256]; // Buffer to collect a line

    while (1)
    {
        uint32_t events = furi_thread_flags_wait(WorkerEvtStop | WorkerEvtRxDone, FuriFlagWaitAny, FuriWaitForever);
        if (events & WorkerEvtStop)
            break;
        if (events & WorkerEvtRxDone)
        {
            size_t len = furi_stream_buffer_receive(fhttp.flipper_http_stream, fhttp.rx_buf, RX_BUF_SIZE * 10, 0);
            for (size_t i = 0; i < len; i++)
            {
                char c = fhttp.rx_buf[i];
                if (c == '\n' || rx_line_pos >= sizeof(rx_line_buffer) - 1)
                {
                    rx_line_buffer[rx_line_pos] = '\0';
                    // Invoke the callback with the complete line
                    if (fhttp.handle_rx_line_cb)
                    {
                        fhttp.handle_rx_line_cb(rx_line_buffer, fhttp.callback_context);
                    }
                    // Reset the line buffer
                    rx_line_pos = 0;
                }
                else
                {
                    rx_line_buffer[rx_line_pos++] = c;
                }
            }
        }
    }

    return 0;
}

// UART initialization function
/**
 * @brief      Initialize UART.
 * @return     true if the UART was initialized successfully, false otherwise.
 * @param      callback  The callback function to handle received data (ex. flipper_http_rx_callback).
 * @param      context   The context to pass to the callback.
 * @note       The received data will be handled asynchronously via the callback.
 */
bool flipper_http_init(FlipperHTTP_Callback callback, void *context)
{
    fhttp.flipper_http_stream = furi_stream_buffer_alloc(RX_BUF_SIZE, 1);
    if (!fhttp.flipper_http_stream)
    {
        FURI_LOG_E(HTTP_TAG, "Failed to allocate UART stream buffer.");
        return false;
    }

    fhttp.rx_thread = furi_thread_alloc();
    if (!fhttp.rx_thread)
    {
        FURI_LOG_E(HTTP_TAG, "Failed to allocate UART thread.");
        furi_stream_buffer_free(fhttp.flipper_http_stream);
        return false;
    }

    furi_thread_set_name(fhttp.rx_thread, "FlipperHTTP_RxThread");
    furi_thread_set_stack_size(fhttp.rx_thread, 1024);
    furi_thread_set_context(fhttp.rx_thread, &fhttp);
    furi_thread_set_callback(fhttp.rx_thread, flipper_http_worker);

    fhttp.handle_rx_line_cb = callback;
    fhttp.callback_context = context;

    furi_thread_start(fhttp.rx_thread);
    fhttp.rx_thread_id = furi_thread_get_id(fhttp.rx_thread);

    // Initialize GPIO pins for UART
    furi_hal_gpio_init_simple(&test_pins[0], GpioModeInput);
    furi_hal_gpio_init_simple(&test_pins[1], GpioModeOutputPushPull);

    fhttp.serial_handle = NULL;

    fhttp.serial_handle = furi_hal_serial_control_acquire(UART_CH);
    if (fhttp.serial_handle == NULL)
    {
        FURI_LOG_E(HTTP_TAG, "Failed to acquire UART control - handle is NULL");
        // Cleanup resources
        furi_thread_free(fhttp.rx_thread);
        furi_stream_buffer_free(fhttp.flipper_http_stream);
        return false;
    }

    // Initialize UART with acquired handle
    furi_hal_serial_init(fhttp.serial_handle, BAUDRATE);

    // Enable RX direction
    furi_hal_serial_enable_direction(fhttp.serial_handle, FuriHalSerialDirectionRx);

    // Start asynchronous RX with the callback
    furi_hal_serial_async_rx_start(fhttp.serial_handle, _flipper_http_rx_callback, &fhttp, false);

    // Wait for the TX to complete to ensure UART is ready
    furi_hal_serial_tx_wait_complete(fhttp.serial_handle);

    // Allocate the timer for handling timeouts
    fhttp.get_timeout_timer = furi_timer_alloc(
        get_timeout_timer_callback, // Callback function
        FuriTimerTypeOnce,          // One-shot timer
        &fhttp                      // Context passed to callback
    );

    if (!fhttp.get_timeout_timer)
    {
        FURI_LOG_E(HTTP_TAG, "Failed to allocate GET timeout timer.");
        // Cleanup resources
        furi_hal_serial_async_rx_stop(fhttp.serial_handle);
        furi_hal_serial_disable_direction(fhttp.serial_handle, FuriHalSerialDirectionRx);
        furi_hal_serial_control_release(fhttp.serial_handle);
        furi_hal_serial_deinit(fhttp.serial_handle);
        furi_thread_flags_set(fhttp.rx_thread_id, WorkerEvtStop);
        furi_thread_join(fhttp.rx_thread);
        furi_thread_free(fhttp.rx_thread);
        furi_stream_buffer_free(fhttp.flipper_http_stream);
        return false;
    }

    // Set the timer thread priority if needed
    furi_timer_set_thread_priority(FuriTimerThreadPriorityElevated);

    FURI_LOG_I(HTTP_TAG, "UART initialized successfully.");
    return true;
}

// Deinitialize UART
/**
 * @brief      Deinitialize UART.
 * @return     void
 * @note       This function will stop the asynchronous RX, release the serial handle, and free the resources.
 */
void flipper_http_deinit()
{
    if (fhttp.serial_handle == NULL)
    {
        FURI_LOG_E(HTTP_TAG, "UART handle is NULL. Already deinitialized?");
        return;
    }
    // Stop asynchronous RX
    furi_hal_serial_async_rx_stop(fhttp.serial_handle);

    // Release and deinitialize the serial handle
    furi_hal_serial_disable_direction(fhttp.serial_handle, FuriHalSerialDirectionRx);
    furi_hal_serial_control_release(fhttp.serial_handle);
    furi_hal_serial_deinit(fhttp.serial_handle);

    // Signal the worker thread to stop
    furi_thread_flags_set(fhttp.rx_thread_id, WorkerEvtStop);
    // Wait for the thread to finish
    furi_thread_join(fhttp.rx_thread);
    // Free the thread resources
    furi_thread_free(fhttp.rx_thread);

    // Free the stream buffer
    furi_stream_buffer_free(fhttp.flipper_http_stream);

    // Free the timer
    if (fhttp.get_timeout_timer)
    {
        furi_timer_free(fhttp.get_timeout_timer);
        fhttp.get_timeout_timer = NULL;
    }

    // Free received data if any
    if (fhttp.received_data)
    {
        free(fhttp.received_data);
        fhttp.received_data = NULL;
    }

    FURI_LOG_I("FlipperHTTP", "UART deinitialized successfully.");
}

// Function to send data over UART with newline termination
/**
 * @brief      Send data over UART with newline termination.
 * @return     true if the data was sent successfully, false otherwise.
 * @param      data  The data to send over UART.
 * @note       The data will be sent over UART with a newline character appended.
 */
bool flipper_http_send_data(const char *data)
{
    size_t data_length = strlen(data);
    if (data_length == 0)
    {
        FURI_LOG_E("FlipperHTTP", "Attempted to send empty data.");
        return false;
    }

    // Create a buffer with data + '\n'
    size_t send_length = data_length + 1; // +1 for '\n'
    if (send_length > 256)
    { // Ensure buffer size is sufficient
        FURI_LOG_E("FlipperHTTP", "Data too long to send over FHTTP.");
        return false;
    }

    char send_buffer[257]; // 256 + 1 for safety
    strncpy(send_buffer, data, 256);
    send_buffer[data_length] = '\n';     // Append newline
    send_buffer[data_length + 1] = '\0'; // Null-terminate

    if (fhttp.state == INACTIVE && ((strstr(send_buffer, "[PING]") == NULL) && (strstr(send_buffer, "[WIFI/CONNECT]") == NULL)))
    {
        FURI_LOG_E("FlipperHTTP", "Cannot send data while INACTIVE.");
        fhttp.last_response = "Cannot send data while INACTIVE.";
        return false;
    }

    fhttp.state = SENDING;
    furi_hal_serial_tx(fhttp.serial_handle, (const uint8_t *)send_buffer, send_length);

    // Uncomment below line to log the data sent over UART
    // FURI_LOG_I("FlipperHTTP", "Sent data over UART: %s", send_buffer);
    fhttp.state = IDLE;
    return true;
}

// Function to send a PING request
/**
 * @brief      Send a GET request to the specified URL.
 * @return     true if the request was successful, false otherwise.
 * @param      url  The URL to send the GET request to.
 * @note       The received data will be handled asynchronously via the callback.
 * @note       This is best used to check if the Wifi Dev Board is connected.
 * @note       The state will remain INACTIVE until a PONG is received.
 */
bool flipper_http_ping()
{
    const char *command = "[PING]";
    if (!flipper_http_send_data(command))
    {
        FURI_LOG_E("FlipperHTTP", "Failed to send PING command.");
        return false;
    }
    // set state as INACTIVE to be made IDLE if PONG is received
    fhttp.state = INACTIVE;
    // The response will be handled asynchronously via the callback
    return true;
}

// Function to save WiFi settings (returns true if successful)
/**
 * @brief      Send a command to save WiFi settings.
 * @return     true if the request was successful, false otherwise.
 * @note       The received data will be handled asynchronously via the callback.
 */
bool flipper_http_save_wifi(const char *ssid, const char *password)
{
    if (!ssid || !password)
    {
        FURI_LOG_E("FlipperHTTP", "Invalid arguments provided to flipper_http_save_wifi.");
        return false;
    }
    char buffer[256];
    int ret = snprintf(buffer, sizeof(buffer), "[WIFI/SAVE]{\"ssid\":\"%s\",\"password\":\"%s\"}", ssid, password);
    if (ret < 0 || ret >= (int)sizeof(buffer))
    {
        FURI_LOG_E("FlipperHTTP", "Failed to format WiFi save command.");
        return false;
    }

    if (!flipper_http_send_data(buffer))
    {
        FURI_LOG_E("FlipperHTTP", "Failed to send WiFi save command.");
        return false;
    }

    // The response will be handled asynchronously via the callback
    return true;
}

// Function to disconnect from WiFi (returns true if successful)
/**
 * @brief      Send a command to disconnect from WiFi.
 * @return     true if the request was successful, false otherwise.
 * @note       The received data will be handled asynchronously via the callback.
 */
bool flipper_http_disconnect_wifi()
{
    const char *command = "[WIFI/DISCONNECT]";
    if (!flipper_http_send_data(command))
    {
        FURI_LOG_E("FlipperHTTP", "Failed to send WiFi disconnect command.");
        return false;
    }

    // The response will be handled asynchronously via the callback
    return true;
}

// Function to connect to WiFi (returns true if successful)
/**
 * @brief      Send a command to connect to WiFi.
 * @return     true if the request was successful, false otherwise.
 * @note       The received data will be handled asynchronously via the callback.
 */
bool flipper_http_connect_wifi()
{
    const char *command = "[WIFI/CONNECT]";
    if (!flipper_http_send_data(command))
    {
        FURI_LOG_E("FlipperHTTP", "Failed to send WiFi connect command.");
        return false;
    }

    // The response will be handled asynchronously via the callback
    return true;
}

// Function to send a GET request
/**
 * @brief      Send a GET request to the specified URL.
 * @return     true if the request was successful, false otherwise.
 * @param      url  The URL to send the GET request to.
 * @note       The received data will be handled asynchronously via the callback.
 */
bool flipper_http_get_request(const char *url)
{
    if (!url)
    {
        FURI_LOG_E("FlipperHTTP", "Invalid arguments provided to flipper_http_get_request.");
        return false;
    }

    // Prepare GET request command
    char command[256];
    int ret = snprintf(command, sizeof(command), "[GET]%s", url);
    if (ret < 0 || ret >= (int)sizeof(command))
    {
        FURI_LOG_E("FlipperHTTP", "Failed to format GET request command.");
        return false;
    }

    // Send GET request via UART
    if (!flipper_http_send_data(command))
    {
        FURI_LOG_E("FlipperHTTP", "Failed to send GET request command.");
        return false;
    }

    // The response will be handled asynchronously via the callback
    return true;
}

// Function to handle received data asynchronously
/**
 * @brief      Callback function to handle received data asynchronously.
 * @return     void
 * @param      line     The received line.
 * @param      context  The context passed to the callback.
 * @note       The received data will be handled asynchronously via the callback and handles the state of the UART.
 */
void flipper_http_rx_callback(const char *line, void *context)
{

    if (!line || !context)
    {
        FURI_LOG_E(HTTP_TAG, "Invalid arguments provided to flipper_http_rx_callback.");
        return;
    }

    fhttp.last_response = (char *)line;

    // the only way for the state to change from INACTIVE to RECEIVING is if a PONG is received
    if (fhttp.state != INACTIVE)
    {
        fhttp.state = RECEIVING;
    }

    // Uncomment below line to log the data received over UART
    // FURI_LOG_I(HTTP_TAG, "Received UART line: %s", line);

    // Check if we've started receiving data from a GET request
    if (fhttp.started_receiving)
    {
        // Restart the timeout timer each time new data is received
        furi_timer_restart(fhttp.get_timeout_timer, TIMEOUT_DURATION_TICKS);

        if (strstr(line, "[GET/END]") != NULL)
        {
            FURI_LOG_I(HTTP_TAG, "GET request completed.");
            // Stop the timer since we've completed the GET request
            furi_timer_stop(fhttp.get_timeout_timer);

            if (fhttp.received_data)
            {
                flipper_http_save_received_data(strlen(fhttp.received_data), fhttp.received_data);
                free(fhttp.received_data);
                fhttp.received_data = NULL;
                fhttp.started_receiving = false;
                fhttp.just_started = false;
                fhttp.state = IDLE;
                return;
            }
            else
            {
                FURI_LOG_E(HTTP_TAG, "No data received.");
                fhttp.started_receiving = false;
                fhttp.just_started = false;
                fhttp.state = IDLE;
                return;
            }
        }

        // Append the new line to the existing data
        if (fhttp.received_data == NULL)
        {
            fhttp.received_data = (char *)malloc(strlen(line) + 2); // +2 for newline and null terminator
            if (fhttp.received_data)
            {
                strcpy(fhttp.received_data, line);
                fhttp.received_data[strlen(line)] = '\n';     // Add newline
                fhttp.received_data[strlen(line) + 1] = '\0'; // Null terminator
            }
        }
        else
        {
            size_t current_len = strlen(fhttp.received_data);
            size_t new_size = current_len + strlen(line) + 2; // +2 for newline and null terminator
            fhttp.received_data = (char *)realloc(fhttp.received_data, new_size);
            if (fhttp.received_data)
            {
                memcpy(fhttp.received_data + current_len, line, strlen(line)); // Copy line at the end of the current data
                fhttp.received_data[current_len + strlen(line)] = '\n';        // Add newline
                fhttp.received_data[current_len + strlen(line) + 1] = '\0';    // Null terminator
            }
        }

        if (!fhttp.just_started)
        {
            fhttp.just_started = true;
        }
        return;
    }

    // Handle different types of responses
    if (strstr(line, "[SUCCESS]") != NULL || strstr(line, "[CONNECTED]") != NULL)
    {
        FURI_LOG_I(HTTP_TAG, "Operation succeeded.");
    }
    else if (strstr(line, "[INFO]") != NULL)
    {
        FURI_LOG_I(HTTP_TAG, "Received info: %s", line);

        if (fhttp.state == INACTIVE && strstr(line, "[INFO] Already connected to Wifi.") != NULL)
        {
            fhttp.state = IDLE;
        }
    }
    else if (strstr(line, "[GET/SUCCESS]") != NULL)
    {
        FURI_LOG_I(HTTP_TAG, "GET request succeeded.");
        fhttp.started_receiving = true;
        furi_timer_start(fhttp.get_timeout_timer, TIMEOUT_DURATION_TICKS);
        fhttp.state = RECEIVING;
        return;
    }
    else if (strstr(line, "[DISCONNECTED]") != NULL)
    {
        FURI_LOG_I(HTTP_TAG, "WiFi disconnected successfully.");
    }
    else if (strstr(line, "[ERROR]") != NULL)
    {
        FURI_LOG_E(HTTP_TAG, "Received error: %s", line);
        fhttp.state = ISSUE;
        return;
    }
    else if (strstr(line, "[PONG]") != NULL)
    {
        FURI_LOG_I(HTTP_TAG, "Received PONG response: Wifi Dev Board is still alive.");

        // send command to connect to WiFi
        if (fhttp.state == INACTIVE)
        {
            fhttp.state = IDLE;
            return;
        }
    }

    if (fhttp.state == INACTIVE && strstr(line, "[PONG]") != NULL)
    {
        fhttp.state = IDLE;
    }
    else if (fhttp.state == INACTIVE && strstr(line, "[PONG]") == NULL)
    {
        fhttp.state = INACTIVE;
    }
    else
    {
        fhttp.state = IDLE;
    }
}
// Function to save received data to a file
/**
 * @brief      Save the received data to a file.
 * @return     true if the data was saved successfully, false otherwise.
 * @param      bytes_received  The number of bytes received.
 * @param      line_buffer     The buffer containing the received data.
 * @note       The data will be saved to a file in the STORAGE_EXT_PATH_PREFIX "/apps_data/" http_tag "/received_data.txt" directory.
 */
bool flipper_http_save_received_data(size_t bytes_received, const char line_buffer[])
{
    const char *output_file_path = STORAGE_EXT_PATH_PREFIX "/apps_data/" http_tag "/received_data.txt";

    // Ensure the directory exists
    char directory_path[128];
    snprintf(directory_path, sizeof(directory_path), STORAGE_EXT_PATH_PREFIX "/apps_data/" http_tag);

    Storage *_storage = NULL;
    File *_file = NULL;
    // Open the storage if not opened already
    // Initialize storage and create the directory if it doesn't exist
    _storage = furi_record_open(RECORD_STORAGE);
    storage_common_mkdir(_storage, directory_path); // Create directory if it doesn't exist
    _file = storage_file_alloc(_storage);

    // Open file for writing and append data line by line
    if (!storage_file_open(_file, output_file_path, FSAM_WRITE, FSOM_CREATE_ALWAYS))
    {
        FURI_LOG_E(HTTP_TAG, "Failed to open output file for writing.");
        storage_file_free(_file);
        furi_record_close(RECORD_STORAGE);
        return false;
    }

    // Write each line received from the UART to the file
    if (bytes_received > 0 && _file)
    {
        storage_file_write(_file, line_buffer, bytes_received);
        storage_file_write(_file, "\n", 1); // Add a newline after each line
    }
    else
    {
        FURI_LOG_E(HTTP_TAG, "No data received.");
        return false;
    }

    if (_file)
    {
        storage_file_close(_file);
        storage_file_free(_file);
        _file = NULL;
    }
    if (_storage)
    {
        furi_record_close(RECORD_STORAGE);
        _storage = NULL;
    }

    return true;
}

#endif // FLIPPER_HTTP_H