#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/queue.h"

static QueueHandle_t msgQueue;

void senderTask(void *pvParameters) {
    int count = 0;
    while (1) {
        char *msg = malloc(50);
        if (msg == NULL) {
            printf("Malloc failed in sender\n");
            break;
        }
        // Prepare a message in the allocated buffer
        snprintf(msg, 50, "Hello from sender, count=%d", count++);
        // Send the pointer to the message via queue
        if (!xQueueSend(msgQueue, &msg, pdMS_TO_TICKS(100))) {
            printf("Failed to send message pointer\n");
            free(msg);  // free if not successfully sent
        } else {
            // Mistake: Freeing the message immediately after sending
           // free(msg);  // message is freed while receiver may not have processed it yet
        }
        // **Fix:** Do NOT free here. Transfer ownership to receiver task.
        // (Receiver should free the message after using it.)
        vTaskDelay(pdMS_TO_TICKS(1000));
    }
    vTaskDelete(NULL);
}

void receiverTask(void *pvParameters) {
    char *receivedMsg = NULL;
    while (1) {
        if (xQueueReceive(msgQueue, &receivedMsg, portMAX_DELAY)) {
            // Use the received message pointer
            printf("Receiver got: %s\n", receivedMsg);

            // Here, receivedMsg might be pointing to freed memory (undefined content).
            // If the sender freed it already, this use is invalid.
            free(receivedMsg);  // **Fix:** Only free here if sender did not free the memory.
        }
        // Simulate processing time
        vTaskDelay(pdMS_TO_TICKS(500));
    }
    // vTaskDelete(NULL); // (Not reached in this example, as receiver runs indefinitely)
}

void app_main() {
    // Create a queue to send message pointers between tasks
    msgQueue = xQueueCreate(5, sizeof(char *));
    xTaskCreate(senderTask, "SenderTask", 4096, NULL, 1, NULL);
    xTaskCreate(receiverTask, "ReceiverTask", 4096, NULL, 1, NULL);
    vTaskDelete(NULL);
}