/* Private */
#include "nh_ctrl_api.h"

#include "protobuf-c/protobuf-c.h"

/* PB config */
#include "esp_hosted_config.pb-c.h"

#define NH_COMMAND_TIMEOUT_MSEC 30000
#define NH_COMMAND_REQ_MEM_SIZE 256

static nh_ret_t nh_ctrl_api_parse_event(nh_ctrl_api_t *api, CtrlMsgId *event_id, uint8_t *buf, uint32_t buf_len);
static void     nh_ctrl_api_dispatch_event(nh_ctrl_api_t *api, CtrlMsgId event_id);
static nh_ret_t nh_ctrl_api_general_request(nh_ctrl_api_t *api, CtrlMsg *tx_msg);
static nh_ret_t nh_ctrl_api_general_response(nh_ctrl_api_t *api, CtrlMsg *rx_msg);
static nh_ret_t nh_ctrl_api_general_response_free(nh_ctrl_api_t *api);
static bool     nh_ctrl_api_payload_decode_cb(pb_istream_t *stream, const pb_field_t *field, void **arg);

nh_ret_t nh_ctrl_api_init(nh_ctrl_api_t *api) {
    nh_ret_t ret = NH_RET_SUCCESS;

    ret = api->osa->sem_create(api->osa->user_data, &api->p_sem_req);
    if (ret != NH_RET_SUCCESS) {
        return ret;
    }

    ret = api->osa->sem_create(api->osa->user_data, &api->p_sem_resp);
    if (ret != NH_RET_SUCCESS) {
        goto free_sem_req;
    }

    ret = api->osa->sem_give(api->osa->user_data, api->p_sem_req);
    if (ret != NH_RET_SUCCESS) {
        goto free_sem_resp;
    }

    return ret;

free_sem_resp:
    api->osa->sem_destroy(api->osa->user_data, api->p_sem_resp);

free_sem_req:
    api->osa->sem_destroy(api->osa->user_data, api->p_sem_req);

    return ret;
}

nh_ret_t nh_ctrl_api_get_mac_address(nh_ctrl_api_t *api, uint8_t *mac_addr) {
    nh_ret_t ret = NH_RET_SUCCESS;

    ret = api->osa->sem_take(api->osa->user_data, api->p_sem_req, NH_COMMAND_TIMEOUT_MSEC);
    if (ret != NH_RET_SUCCESS) {
        return ret;
    }

    CtrlMsg tx_msg;

    ret = nh_ctrl_api_general_request(api, &tx_msg);
    if (ret != NH_RET_SUCCESS) {
        goto give_sem_exit;
    }

    CtrlMsg rx_msg;

    ret = nh_ctrl_api_general_response(api, &rx_msg);
    if (ret != NH_RET_SUCCESS) {
        goto give_sem_exit;
    }

    nh_ctrl_api_general_response_free(api);

give_sem_exit:
    api->osa->sem_give(api->osa->user_data, api->p_sem_req);

    return ret;
}

void nh_ctrl_api_task(nh_ctrl_api_t *api) {
    nh_ret_t ret = NH_RET_SUCCESS;

    uint8_t            *payload;
    uint32_t            payload_size;
    nh_serial_ep_type_t ep_type;

    ret = nh_shared_if_serial_if_recv(api->shared_if, &ep_type, &payload, &payload_size, NH_COMMAND_TIMEOUT_MSEC);
    if (ret != NH_RET_SUCCESS) {
        return;
    }

    if (ep_type == NH_SERIAL_EP_RESP) {
        api->p_buf_rx     = payload;
        api->p_buf_rx_len = payload_size;

        ret = api->osa->sem_give(api->osa->user_data, api->p_sem_resp);
        if (ret != NH_RET_SUCCESS) {
            nh_shared_if_serial_if_free(api->shared_if, payload);
            return;
        }
    } else if (ep_type == NH_SERIAL_EP_EVENT) {
        CtrlMsgId event_id;
        ret = nh_ctrl_api_parse_event(api, &event_id, payload, payload_size);
        if (ret == NH_RET_SUCCESS) {
            nh_ctrl_api_dispatch_event(api, event_id);
        }

        nh_shared_if_serial_if_free(api->shared_if, payload);
    }
}

static nh_ret_t nh_ctrl_api_parse_event(nh_ctrl_api_t *api, CtrlMsgId *event_id, uint8_t *buf, uint32_t buf_len) {
    pb_istream_t stream = pb_istream_from_buffer(buf, buf_len);

    CtrlMsg event_msg = CtrlMsg_init_zero;

    if (!pb_decode(&stream, CtrlMsg_fields, &event_msg)) {
        return NH_RET_FAIL;
    }

    *event_id = event_msg.msg_id;

    return NH_RET_SUCCESS;
}

static void nh_ctrl_api_dispatch_event(nh_ctrl_api_t *api, CtrlMsgId event_id) {
    switch (event_id) {
        case CTRL_MSG_ID__Event_ESPInit: {
            if (api->cb.init) {
                api->cb.init(api->user_data);
            }

            break;
        }

        default:
            break;
    }
}

static nh_ret_t nh_ctrl_api_general_request(nh_ctrl_api_t *api, CtrlMsg *tx_msg) {
    nh_ret_t ret = NH_RET_SUCCESS;

    uint8_t *req_buf;
    ret = api->osa->buf_allocate(api->osa->user_data, &req_buf, NH_COMMAND_REQ_MEM_SIZE);
    if (ret != NH_RET_SUCCESS) {
        return ret;
    }

    pb_ostream_t tx_stream = pb_ostream_from_buffer(req_buf, NH_COMMAND_REQ_MEM_SIZE);
    if (!pb_encode(&tx_stream, CtrlMsg_fields, tx_msg)) {
        /* False on error: */
        ret = NH_RET_FAIL;
        goto free_tx_exit;
    }

    ret = nh_shared_if_serial_if_send(api->shared_if, req_buf, tx_stream.bytes_written, NH_COMMAND_TIMEOUT_MSEC);

free_tx_exit:
    api->osa->buf_free(api->osa->user_data, req_buf);

    return ret;
}

static nh_ret_t nh_ctrl_api_general_response(nh_ctrl_api_t *api, CtrlMsg *rx_msg) {
    nh_ret_t ret = NH_RET_SUCCESS;

    ret = api->osa->sem_take(api->osa->user_data, api->p_sem_resp, NH_COMMAND_TIMEOUT_MSEC);
    if (ret != NH_RET_SUCCESS) {
        return ret;
    }

    pb_istream_t rx_stream = pb_istream_from_buffer(api->p_buf_rx, api->p_buf_rx_len);

    rx_msg->cb_payload.funcs.decode = nh_ctrl_api_payload_decode_cb;

    if (!pb_decode(&rx_stream, CtrlMsg_fields, rx_msg)) {
        nh_shared_if_serial_if_free(api->shared_if, api->p_buf_rx);
        return NH_RET_FAIL;
    }

    return ret;
}

static nh_ret_t nh_ctrl_api_general_response_free(nh_ctrl_api_t *api) {
    return nh_shared_if_serial_if_free(api->shared_if, api->p_buf_rx);
}

static bool nh_ctrl_api_bytes_decode_cb(pb_istream_t *stream, const pb_field_t *field, void **arg) {
    if (stream->bytes_left) {
        return pb_read(stream, *arg, stream->bytes_left);
    }

    return true;
}

static bool nh_ctrl_api_payload_decode_cb(pb_istream_t *stream, const pb_field_t *field, void **arg) {
    if (field->tag == CtrlMsg_resp_get_mac_address_tag) {
        CtrlMsg_Resp_GetMacAddress *sub_msg = field->pData;

        sub_msg->mac.funcs.decode = nh_ctrl_api_bytes_decode_cb;
        sub_msg->mac.arg          = *arg;
    }

    return true;
}