desklock/firmware/main/gw_client.c

/* WebSocket link to the DeskLock gateway.
 * Protocol: docs/architecture.md "WebSocket protocol" — keep in sync.
 */

#include <string.h>

#include "cJSON.h"
#include "esp_app_desc.h"
#include "esp_log.h"
#include "esp_websocket_client.h"

#include "desklock.h"
#include "secrets.h"

static const char *TAG = "gw";

static esp_websocket_client_handle_t s_ws;
static volatile bool s_connected;

static void handle_text(const char *data, int len)
{
    cJSON *root = cJSON_ParseWithLength(data, len);
    if (root == NULL) {
        return;
    }
    const cJSON *type = cJSON_GetObjectItem(root, "type");
    if (!cJSON_IsString(type)) {
        cJSON_Delete(root);
        return;
    }
    face_activity();

    if (strcmp(type->valuestring, "state") == 0) {
        const cJSON *value = cJSON_GetObjectItem(root, "value");
        if (cJSON_IsString(value)) {
            if (strcmp(value->valuestring, "thinking") == 0) {
                face_set(FACE_EFFORT);
            } else if (strcmp(value->valuestring, "idle") == 0 && !audio_is_playing()) {
                face_set(FACE_IDLE);
            }
        }
    } else if (strcmp(type->valuestring, "transcript") == 0) {
        const cJSON *text = cJSON_GetObjectItem(root, "text");
        ESP_LOGI(TAG, "transcript: %s", cJSON_IsString(text) ? text->valuestring : "?");
    } else if (strcmp(type->valuestring, "reply_text") == 0) {
        const cJSON *text = cJSON_GetObjectItem(root, "text");
        ESP_LOGI(TAG, "tatlock: %s", cJSON_IsString(text) ? text->valuestring : "?");
    } else if (strcmp(type->valuestring, "audio_start") == 0) {
        audio_playback_begin();
        face_set(FACE_SPEAKING);
    } else if (strcmp(type->valuestring, "audio_end") == 0) {
        audio_playback_end();
    } else if (strcmp(type->valuestring, "error") == 0) {
        face_set(FACE_RAGE);
    }
    cJSON_Delete(root);
}

static void ws_event(void *arg, esp_event_base_t base, int32_t id, void *data)
{
    (void)arg;
    (void)base;
    esp_websocket_event_data_t *ev = (esp_websocket_event_data_t *)data;
    switch (id) {
    case WEBSOCKET_EVENT_CONNECTED: {
        ESP_LOGI(TAG, "gateway connected");
        s_connected = true;
        char hello[128];
        snprintf(hello, sizeof(hello),
                 "{\"type\":\"hello\",\"device\":\"desklock-p4\",\"fw\":\"%s\"}",
                 esp_app_get_description()->version);
        gw_send_text(hello);
        face_set(FACE_IDLE);
        break;
    }
    case WEBSOCKET_EVENT_DISCONNECTED:
    case WEBSOCKET_EVENT_ERROR:
        if (s_connected) {
            ESP_LOGW(TAG, "gateway lost");
        }
        s_connected = false;
        audio_capture_stop();
        app_on_disconnect();
        /* Stay calm: the rain draining away signals "unreachable". A sustained
         * outage escalates to the x_x error face in face.c (clock_cb). */
        face_set(FACE_IDLE);
        break;
    case WEBSOCKET_EVENT_DATA:
        if (ev->op_code == 0x01) { /* text */
            handle_text(ev->data_ptr, ev->data_len);
        } else if (ev->op_code == 0x02 && ev->data_len > 0) { /* binary PCM */
            audio_playback_feed((const uint8_t *)ev->data_ptr, ev->data_len);
        }
        break;
    default:
        break;
    }
}

void gw_start(void)
{
    if (s_ws != NULL) {
        return;
    }
    esp_websocket_client_config_t cfg = {
        .uri = GATEWAY_WS_URI,
        .buffer_size = 8192,
        .reconnect_timeout_ms = 5000,
        .network_timeout_ms = 10000,
        .ping_interval_sec = 8, /* keep the link visibly alive through long Tatlock turns */
    };
    s_ws = esp_websocket_client_init(&cfg);
    esp_websocket_register_events(s_ws, WEBSOCKET_EVENT_ANY, ws_event, NULL);
    esp_websocket_client_start(s_ws);
    ESP_LOGI(TAG, "connecting to %s", GATEWAY_WS_URI);
}

bool gw_connected(void)
{
    return s_connected;
}

void gw_send_text(const char *json)
{
    if (s_connected) {
        esp_websocket_client_send_text(s_ws, json, strlen(json), pdMS_TO_TICKS(1500));
    }
}

void gw_send_bin(const uint8_t *data, size_t len)
{
    if (s_connected) {
        esp_websocket_client_send_bin(s_ws, (const char *)data, len, pdMS_TO_TICKS(1500));
    }
}