/*****************************************************************************
**
**  Name:       avrc_bld_tg.c
**
**  Description:Interface to AVRCP build message functions for the Target Role
**
**  Copyright (c) 2008-2008, Broadcom Corp., All Rights Reserved.
**  Broadcom Bluetooth Core. Proprietary and confidential.
**
*****************************************************************************/
#include <string.h>

#include "gki.h"
#include "avrc_api.h"
#include "avrc_defs.h"
#include "avrc_int.h"

/*****************************************************************************
**  Global data
*****************************************************************************/
#if (AVRC_METADATA_INCLUDED == TRUE)

/*******************************************************************************
**
** Function         avrc_bld_get_capability_rsp
**
** Description      This function builds the Get Capability response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_get_capability_rsp (tAVRC_GET_CAPS_RSP *p_rsp, BT_HDR *p_pkt)
{
    UINT8   *p_data, *p_start, *p_len, *p_count;
    UINT16  len = 0;
    UINT8   xx;
    UINT32  *p_company_id;
    UINT8   *p_event_id;
    tAVRC_STS status = AVRC_STS_NO_ERROR;

    if (!(AVRC_IS_VALID_CAP_ID(p_rsp->capability_id)))
    {
        AVRC_TRACE_ERROR1("avrc_bld_get_capability_rsp bad parameter. p_rsp: %x", p_rsp);
        status = AVRC_STS_BAD_PARAM;
        return status;
    }

    AVRC_TRACE_API0("avrc_bld_get_capability_rsp");
    /* get the existing length, if any, and also the num attributes */
    p_start = (UINT8 *)(p_pkt + 1) + p_pkt->offset;
    p_data = p_len = p_start + 2; /* pdu + rsvd */

    BE_STREAM_TO_UINT16(len, p_data);
    UINT8_TO_BE_STREAM(p_data, p_rsp->capability_id);
    p_count = p_data;

    if (len == 0)
    {
        *p_count = p_rsp->count;
        p_data++;
        len = 2; /* move past the capability_id and count */
    }
    else
    {
        p_data = p_start + p_pkt->len;
        *p_count += p_rsp->count;
    }

    if (p_rsp->capability_id == AVRC_CAP_COMPANY_ID)
    {
        p_company_id = p_rsp->param.company_id;
        for (xx=0; xx< p_rsp->count; xx++)
        {
            UINT24_TO_BE_STREAM(p_data, p_company_id[xx]);
        }
        len += p_rsp->count * 3;
    }
    else
    {
        p_event_id = p_rsp->param.event_id;
        *p_count = 0;
        for (xx=0; xx< p_rsp->count; xx++)
        {
            if (AVRC_IS_VALID_EVENT_ID(p_event_id[xx]))
            {
                (*p_count)++;
                UINT8_TO_BE_STREAM(p_data, p_event_id[xx]);
            }
        }
        len += (*p_count);
    }
    UINT16_TO_BE_STREAM(p_len, len);
    p_pkt->len = (p_data - p_start);
    status = AVRC_STS_NO_ERROR;

    return status;
}

/*******************************************************************************
**
** Function         avrc_bld_list_app_settings_attr_rsp
**
** Description      This function builds the List Application Settings Attribute
**                  response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_list_app_settings_attr_rsp (tAVRC_LIST_APP_ATTR_RSP *p_rsp, BT_HDR *p_pkt)
{
    UINT8   *p_data, *p_start, *p_len, *p_num;
    UINT16  len = 0;
    UINT8   xx;

    AVRC_TRACE_API0("avrc_bld_list_app_settings_attr_rsp");
    /* get the existing length, if any, and also the num attributes */
    p_start = (UINT8 *)(p_pkt + 1) + p_pkt->offset;
    p_data = p_len = p_start + 2; /* pdu + rsvd */

    BE_STREAM_TO_UINT16(len, p_data);
    p_num = p_data;
    if (len == 0)
    {
        /* first time initialize the attribute count */
        *p_num = 0;
        p_data++;
    }
    else
    {
        p_data = p_start + p_pkt->len;
    }

    for (xx=0; xx<p_rsp->num_attr; xx++)
    {
        if(AVRC_IsValidPlayerAttr(p_rsp->attrs[xx]))
        {
            (*p_num)++;
            UINT8_TO_BE_STREAM(p_data, p_rsp->attrs[xx]);
        }
    }

    len = *p_num + 1;
    UINT16_TO_BE_STREAM(p_len, len);
    p_pkt->len = (p_data - p_start);

    return AVRC_STS_NO_ERROR;
}

/*******************************************************************************
**
** Function         avrc_bld_list_app_settings_values_rsp
**
** Description      This function builds the List Application Setting Values
**                  response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_list_app_settings_values_rsp (tAVRC_LIST_APP_VALUES_RSP *p_rsp, BT_HDR *p_pkt)
{
    UINT8   *p_data, *p_start, *p_len, *p_num;
    UINT8   xx;
    UINT16  len;

    AVRC_TRACE_API0("avrc_bld_list_app_settings_values_rsp");

    p_start = (UINT8 *)(p_pkt + 1) + p_pkt->offset;
    p_data = p_len = p_start + 2; /* pdu + rsvd */

    /* get the existing length, if any, and also the num attributes */
    BE_STREAM_TO_UINT16(len, p_data);
    p_num = p_data;
    /* first time initialize the attribute count */
    if (len == 0)
    {
        *p_num = p_rsp->num_val;
        p_data++;
    }
    else
    {
        p_data = p_start + p_pkt->len;
        *p_num += p_rsp->num_val;
    }


    for (xx=0; xx<p_rsp->num_val; xx++)
    {
        UINT8_TO_BE_STREAM(p_data, p_rsp->vals[xx]);
    }

    len = *p_num + 1;
    UINT16_TO_BE_STREAM(p_len, len);
    p_pkt->len = (p_data - p_start);
    return AVRC_STS_NO_ERROR;
}

/*******************************************************************************
**
** Function         avrc_bld_get_cur_app_setting_value_rsp
**
** Description      This function builds the Get Current Application Setting Value
**                  response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_get_cur_app_setting_value_rsp (tAVRC_GET_CUR_APP_VALUE_RSP *p_rsp, BT_HDR *p_pkt)
{
    UINT8   *p_data, *p_start, *p_len, *p_count;
    UINT16  len;
    UINT8   xx;

    if (!p_rsp->p_vals)
    {
        AVRC_TRACE_ERROR0("avrc_bld_get_cur_app_setting_value_rsp NULL parameter");
        return AVRC_STS_BAD_PARAM;
    }

    AVRC_TRACE_API0("avrc_bld_get_cur_app_setting_value_rsp");
    /* get the existing length, if any, and also the num attributes */
    p_start = (UINT8 *)(p_pkt + 1) + p_pkt->offset;
    p_data = p_len = p_start + 2; /* pdu + rsvd */

    BE_STREAM_TO_UINT16(len, p_data);
    p_count = p_data;
    if (len == 0)
    {
        /* first time initialize the attribute count */
        *p_count = 0;
        p_data++;
    }
    else
    {
        p_data = p_start + p_pkt->len;
    }

    for (xx=0; xx<p_rsp->num_val; xx++)
    {
        if (avrc_is_valid_player_attrib_value(p_rsp->p_vals[xx].attr_id, p_rsp->p_vals[xx].attr_val))
        {
            (*p_count)++;
            UINT8_TO_BE_STREAM(p_data, p_rsp->p_vals[xx].attr_id);
            UINT8_TO_BE_STREAM(p_data, p_rsp->p_vals[xx].attr_val);
        }
    }
    len = ((*p_count) << 1) + 1;
    UINT16_TO_BE_STREAM(p_len, len);
    p_pkt->len = (p_data - p_start);

    return AVRC_STS_NO_ERROR;
}

/*******************************************************************************
**
** Function         avrc_bld_set_app_setting_value_rsp
**
** Description      This function builds the Set Application Setting Value
**                  response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_set_app_setting_value_rsp (tAVRC_RSP *p_rsp, BT_HDR *p_pkt)
{
    /* nothing to be added. */
    AVRC_TRACE_API0("avrc_bld_set_app_setting_value_rsp");
    return AVRC_STS_NO_ERROR;
}

/*******************************************************************************
**
** Function         avrc_bld_app_setting_text_rsp
**
** Description      This function builds the Get Application Settings Attribute Text
**                  or Get Application Settings Value Text response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_app_setting_text_rsp (tAVRC_GET_APP_ATTR_TXT_RSP *p_rsp, BT_HDR *p_pkt)
{
    UINT8   *p_data, *p_start, *p_len, *p_count;
    UINT16  len, len_left;
    UINT8   xx;
    tAVRC_STS   sts = AVRC_STS_NO_ERROR;
    UINT8       num_added = 0;

    if (!p_rsp->p_attrs)
    {
        AVRC_TRACE_ERROR0("avrc_bld_app_setting_text_rsp NULL parameter");
        return AVRC_STS_BAD_PARAM;
    }
    /* get the existing length, if any, and also the num attributes */
    p_start = (UINT8 *)(p_pkt + 1) + p_pkt->offset;
    p_data = p_len = p_start + 2; /* pdu + rsvd */
    len_left = GKI_get_buf_size(p_pkt) - BT_HDR_SIZE - p_pkt->offset - p_pkt->len;

    BE_STREAM_TO_UINT16(len, p_data);
    p_count = p_data;

    if (len == 0)
    {
        *p_count = 0;
        p_data++;
    }
    else
    {
        p_data = p_start + p_pkt->len;
    }

    for (xx=0; xx<p_rsp->num_attr; xx++)
    {
        if  (len_left < (p_rsp->p_attrs[xx].str_len + 4))
        {
            AVRC_TRACE_ERROR3("avrc_bld_app_setting_text_rsp out of room (str_len:%d, left:%d)",
                xx, p_rsp->p_attrs[xx].str_len, len_left);
            p_rsp->num_attr = num_added;
            sts = AVRC_STS_INTERNAL_ERR;
            break;
        }
        if ( !p_rsp->p_attrs[xx].str_len || !p_rsp->p_attrs[xx].p_str )
        {
            AVRC_TRACE_ERROR1("avrc_bld_app_setting_text_rsp NULL attr text[%d]", xx);
            continue;
        }
        UINT8_TO_BE_STREAM(p_data, p_rsp->p_attrs[xx].attr_id);
        UINT16_TO_BE_STREAM(p_data, p_rsp->p_attrs[xx].charset_id);
        UINT8_TO_BE_STREAM(p_data, p_rsp->p_attrs[xx].str_len);
        ARRAY_TO_BE_STREAM(p_data, p_rsp->p_attrs[xx].p_str, p_rsp->p_attrs[xx].str_len);
        (*p_count)++;
        num_added++;
    }
    len = p_data - p_count;
    UINT16_TO_BE_STREAM(p_len, len);
    p_pkt->len = (p_data - p_start);

    return sts;
}

/*******************************************************************************
**
** Function         avrc_bld_get_app_setting_attr_text_rsp
**
** Description      This function builds the Get Application Setting Attribute Text
**                  response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_get_app_setting_attr_text_rsp (tAVRC_GET_APP_ATTR_TXT_RSP *p_rsp, BT_HDR *p_pkt)
{
    AVRC_TRACE_API0("avrc_bld_get_app_setting_attr_text_rsp");
    return avrc_bld_app_setting_text_rsp(p_rsp, p_pkt);
}

/*******************************************************************************
**
** Function         avrc_bld_get_app_setting_value_text_rsp
**
** Description      This function builds the Get Application Setting Value Text
**                  response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_get_app_setting_value_text_rsp (tAVRC_GET_APP_ATTR_TXT_RSP *p_rsp, BT_HDR *p_pkt)
{
    AVRC_TRACE_API0("avrc_bld_get_app_setting_value_text_rsp");
    return avrc_bld_app_setting_text_rsp(p_rsp, p_pkt);
}

/*******************************************************************************
**
** Function         avrc_bld_inform_charset_rsp
**
** Description      This function builds the Inform Displayable Character Set
**                  response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_inform_charset_rsp (tAVRC_RSP *p_rsp, BT_HDR *p_pkt)
{
    /* nothing to be added. */
    AVRC_TRACE_API0("avrc_bld_inform_charset_rsp");
    return AVRC_STS_NO_ERROR;
}

/*******************************************************************************
**
** Function         avrc_bld_inform_battery_status_rsp
**
** Description      This function builds the Inform Battery Status 
**                  response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_inform_battery_status_rsp (tAVRC_RSP *p_rsp, BT_HDR *p_pkt)
{
    /* nothing to be added. */
    AVRC_TRACE_API0("avrc_bld_inform_battery_status_rsp");
    return AVRC_STS_NO_ERROR;
}

/*******************************************************************************
**
** Function         avrc_bld_get_elem_attrs_rsp
**
** Description      This function builds the Get Element Attributes
**                  response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_get_elem_attrs_rsp (tAVRC_GET_ELEM_ATTRS_RSP *p_rsp, BT_HDR *p_pkt)
{
    UINT8   *p_data, *p_start, *p_len, *p_count;
    UINT16  len;
    UINT8   xx;

    AVRC_TRACE_API0("avrc_bld_get_elem_attrs_rsp");
    if (!p_rsp->p_attrs)
    {
        AVRC_TRACE_ERROR0("avrc_bld_get_elem_attrs_rsp NULL parameter");
        return AVRC_STS_BAD_PARAM;
    }

    /* get the existing length, if any, and also the num attributes */
    p_start = (UINT8 *)(p_pkt + 1) + p_pkt->offset;
    p_data = p_len = p_start + 2; /* pdu + rsvd */

    BE_STREAM_TO_UINT16(len, p_data);
    p_count = p_data;

    if (len == 0)
    {
        *p_count = 0;
        p_data++;
    }
    else
    {
        p_data = p_start + p_pkt->len;
    }

    for (xx=0; xx<p_rsp->num_attr; xx++)
    {
        if (!AVRC_IS_VALID_MEDIA_ATTRIBUTE(p_rsp->p_attrs[xx].attr_id))
        {
            AVRC_TRACE_ERROR2("avrc_bld_get_elem_attrs_rsp invalid attr id[%d]: %d", xx, p_rsp->p_attrs[xx].attr_id);
            continue;
        }
        if ( !p_rsp->p_attrs[xx].name.p_str )
        {
            p_rsp->p_attrs[xx].name.str_len = 0;
        }
        UINT32_TO_BE_STREAM(p_data, p_rsp->p_attrs[xx].attr_id);
        UINT16_TO_BE_STREAM(p_data, p_rsp->p_attrs[xx].name.charset_id);
        UINT16_TO_BE_STREAM(p_data, p_rsp->p_attrs[xx].name.str_len);
        ARRAY_TO_BE_STREAM(p_data, p_rsp->p_attrs[xx].name.p_str, p_rsp->p_attrs[xx].name.str_len);
        (*p_count)++;
    }
    len = p_data - p_count;
    UINT16_TO_BE_STREAM(p_len, len);
    p_pkt->len = (p_data - p_start);
    return AVRC_STS_NO_ERROR;
}

/*******************************************************************************
**
** Function         avrc_bld_get_play_status_rsp
**
** Description      This function builds the Get Play Status 
**                  response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_get_play_status_rsp (tAVRC_GET_PLAY_STATUS_RSP *p_rsp, BT_HDR *p_pkt)
{
    UINT8   *p_data, *p_start;

    AVRC_TRACE_API0("avrc_bld_get_play_status_rsp");
    p_start = (UINT8 *)(p_pkt + 1) + p_pkt->offset;
    p_data = p_start + 2;

    /* add fixed lenth - song len(4) + song position(4) + status(1) */
    UINT16_TO_BE_STREAM(p_data, 9);
    UINT32_TO_BE_STREAM(p_data, p_rsp->song_len);
    UINT32_TO_BE_STREAM(p_data, p_rsp->song_pos);
    UINT8_TO_BE_STREAM(p_data, p_rsp->play_status);
    p_pkt->len = (p_data - p_start);

    return AVRC_STS_NO_ERROR;
}

/*******************************************************************************
**
** Function         avrc_bld_notify_rsp
**
** Description      This function builds the Notification response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_notify_rsp (tAVRC_REG_NOTIF_RSP *p_rsp, BT_HDR *p_pkt)
{
    UINT8   *p_data, *p_start;
    UINT8   *p_len;
    UINT16  len = 0;
    UINT8   xx;
    tAVRC_STS status = AVRC_STS_NO_ERROR;

    AVRC_TRACE_API0("avrc_bld_notify_rsp");

    p_start = (UINT8 *)(p_pkt + 1) + p_pkt->offset;
    p_data = p_len = p_start + 2; /* pdu + rsvd */
    p_data += 2;

    UINT8_TO_BE_STREAM(p_data, p_rsp->event_id);
    switch (p_rsp->event_id)
    {
    case AVRC_EVT_PLAY_STATUS_CHANGE:       /* 0x01 */
        /* p_rsp->param.play_status >= AVRC_PLAYSTATE_STOPPED is always TRUE */
        if ((p_rsp->param.play_status <= AVRC_PLAYSTATE_REV_SEEK) ||
            (p_rsp->param.play_status == AVRC_PLAYSTATE_ERROR) )
        {
            UINT8_TO_BE_STREAM(p_data, p_rsp->param.play_status);
            len = 2;
        }
        else
        {
            AVRC_TRACE_ERROR0("bad play state");
            status = AVRC_STS_BAD_PARAM;
        }
        break;

    case AVRC_EVT_TRACK_CHANGE:             /* 0x02 */
        ARRAY_TO_BE_STREAM(p_data, p_rsp->param.track, AVRC_UID_SIZE);
        len = (UINT8)(AVRC_UID_SIZE + 1);
        break;

    case AVRC_EVT_TRACK_REACHED_END:        /* 0x03 */
    case AVRC_EVT_TRACK_REACHED_START:      /* 0x04 */
#if (AVRC_ADV_CTRL_INCLUDED == TRUE)
    case AVRC_EVT_NOW_PLAYING_CHANGE:       /* 0x09 */
    case AVRC_EVT_AVAL_PLAYERS_CHANGE:      /* 0x0a */
#endif
        len = 1;
        break;

    case AVRC_EVT_PLAY_POS_CHANGED:         /* 0x05 */
        UINT32_TO_BE_STREAM(p_data, p_rsp->param.play_pos);
        len = 5;
        break;

    case AVRC_EVT_BATTERY_STATUS_CHANGE:    /* 0x06 */
        if (AVRC_IS_VALID_BATTERY_STATUS(p_rsp->param.battery_status))
        {
            UINT8_TO_BE_STREAM(p_data, p_rsp->param.battery_status);
            len = 2;
        }
        else
        {
            AVRC_TRACE_ERROR0("bad battery status");
            status = AVRC_STS_BAD_PARAM;
        }
        break;

    case AVRC_EVT_SYSTEM_STATUS_CHANGE:     /* 0x07 */
        if (AVRC_IS_VALID_SYSTEM_STATUS(p_rsp->param.system_status))
        {
            UINT8_TO_BE_STREAM(p_data, p_rsp->param.system_status);
            len = 2;
        }
        else
        {
            AVRC_TRACE_ERROR0("bad system status");
            status = AVRC_STS_BAD_PARAM;
        }
        break;

    case AVRC_EVT_APP_SETTING_CHANGE:       /* 0x08 */
        if (p_rsp->param.player_setting.num_attr > AVRC_MAX_APP_SETTINGS)
            p_rsp->param.player_setting.num_attr = AVRC_MAX_APP_SETTINGS;

        if (p_rsp->param.player_setting.num_attr > 0)
        {
            UINT8_TO_BE_STREAM(p_data, p_rsp->param.player_setting.num_attr);
            len = 2;
            for (xx=0; xx<p_rsp->param.player_setting.num_attr; xx++)
            {
                if (avrc_is_valid_player_attrib_value(p_rsp->param.player_setting.attr_id[xx], p_rsp->param.player_setting.attr_value[xx]))
                {
                    UINT8_TO_BE_STREAM(p_data, p_rsp->param.player_setting.attr_id[xx]);
                    UINT8_TO_BE_STREAM(p_data, p_rsp->param.player_setting.attr_value[xx]);
                }
                else
                {
                    AVRC_TRACE_ERROR0("bad player app seeting attribute or value");
                    status = AVRC_STS_BAD_PARAM;
                    break;
                }
                len += 2;
            }
        }
        else
            status = AVRC_STS_BAD_PARAM;
        break;

#if (AVRC_ADV_CTRL_INCLUDED == TRUE)
    case AVRC_EVT_ADDR_PLAYER_CHANGE:       /* 0x0b */
        UINT16_TO_BE_STREAM(p_data, p_rsp->param.addr_player.player_id); /* player_id */
        UINT16_TO_BE_STREAM(p_data, p_rsp->param.addr_player.uid_counter); /* uid counter */
        len = 5;
        break;

    case AVRC_EVT_UIDS_CHANGE:              /* 0x0c */
        UINT16_TO_BE_STREAM(p_data, p_rsp->param.uid_counter); /* uid counter */
        len = 3;
        break;

    case AVRC_EVT_VOLUME_CHANGE:            /* 0x0d */
        UINT8_TO_BE_STREAM(p_data, (UINT8)(p_rsp->param.volume&AVRC_MAX_VOLUME));
        len = 2;
        break;
#endif

    default:
        status = AVRC_STS_BAD_PARAM;
        AVRC_TRACE_ERROR0("unknown event_id");
    }

    UINT16_TO_BE_STREAM(p_len, len);
    p_pkt->len = (p_data - p_start);

    return status;
}

/*******************************************************************************
**
** Function         avrc_bld_next_rsp
**
** Description      This function builds the Request Continue or Abort 
**                  response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_next_rsp (tAVRC_RSP *p_rsp, BT_HDR *p_pkt)
{
    /* nothing to be added. */
    AVRC_TRACE_API0("avrc_bld_next_rsp");
    return AVRC_STS_NO_ERROR;
}

/*******************************************************************************
**
** Function         avrc_bld_group_navigation_rsp
**
** Description      This function builds the Group Navigation
**                  response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
tAVRC_STS avrc_bld_group_navigation_rsp (UINT16 navi_id, BT_HDR *p_pkt)
{
    UINT8   *p_data;

    if (!AVRC_IS_VALID_GROUP(navi_id))
    {
        AVRC_TRACE_ERROR1("avrc_bld_group_navigation_rsp bad navigation op id: %d", navi_id);
        return AVRC_STS_BAD_PARAM;
    }

    AVRC_TRACE_API0("avrc_bld_group_navigation_rsp");
    p_data = (UINT8 *)(p_pkt+1) + p_pkt->offset;
    UINT16_TO_BE_STREAM(p_data, navi_id);
    p_pkt->len = 2;
    return AVRC_STS_NO_ERROR;
}

/*******************************************************************************
**
** Function         avrc_bld_rejected_rsp
**
** Description      This function builds the General Response response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_rejected_rsp( tAVRC_RSP *p_rsp, BT_HDR *p_pkt )
{
    UINT8 *p_data, *p_start;
#if (AVCT_BROWSE_INCLUDED == TRUE)
    UINT8 opcode = avrc_opcode_from_pdu(p_rsp->pdu);
#endif

    AVRC_TRACE_API2("avrc_bld_rejected_rsp: status=%d, pdu:x%x", p_rsp->status, p_rsp->pdu);

    p_start = (UINT8 *)(p_pkt + 1) + p_pkt->offset;
#if (AVCT_BROWSE_INCLUDED == TRUE)
    if (opcode == AVRC_OP_BROWSE)
    {
        p_data = p_start + 1;
        if (avrc_opcode_from_pdu(*p_start) != AVRC_OP_BROWSE)
        {
            /* if the given opcode is not recognized as a browsing command opcode, use general reject command */
            *p_start = AVRC_PDU_GENERAL_REJECT;
        }
    }
    else
#endif
    {
        p_data = p_start + 2;
    }
    AVRC_TRACE_DEBUG1("pdu:x%x", *p_start);

    UINT16_TO_BE_STREAM(p_data, 1);
    UINT8_TO_BE_STREAM(p_data, p_rsp->status);
    p_pkt->len = p_data - p_start;

    return AVRC_STS_NO_ERROR;
}


/*****************************************************************************
**  the following commands are introduced in AVRCP 1.4
*****************************************************************************/

#if (AVRC_ADV_CTRL_INCLUDED == TRUE)
/*******************************************************************************
**
** Function         avrc_bld_ctrl_status_rsp
**
** Description      This function builds the responses with a UINT8 parameter.
**                  
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_ctrl_status_rsp (tAVRC_RSP *p_rsp, BT_HDR *p_pkt)
{
    UINT8   *p_data, *p_start;

    p_start = (UINT8 *)(p_pkt + 1) + p_pkt->offset;
    p_data = p_start + 2; /* pdu + rsvd */

    /* add fixed lenth - status(1) */
    UINT16_TO_BE_STREAM(p_data, 1);
    UINT8_TO_BE_STREAM(p_data, p_rsp->status);
    p_pkt->len = (p_data - p_start);
    return AVRC_STS_NO_ERROR;
}

/*******************************************************************************
**
** Function         avrc_bld_set_addr_player_rsp
**
** Description      This function builds the Set Addresses Player response.
**                  
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_set_addr_player_rsp (tAVRC_RSP *p_rsp, BT_HDR *p_pkt)
{
    AVRC_TRACE_API0("avrc_bld_set_addr_player_rsp");
    return avrc_bld_ctrl_status_rsp(p_rsp, p_pkt);
}

/*******************************************************************************
**
** Function         avrc_bld_set_abs_volume_rsp
**
** Description      This function builds the Set Absolute Volume response.
**                  
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_set_abs_volume_rsp (tAVRC_SET_VOLUME_RSP *p_rsp, BT_HDR *p_pkt)
{
    p_rsp->status = (p_rsp->volume & AVRC_MAX_VOLUME);
    AVRC_TRACE_API2("avrc_bld_set_abs_volume_rsp volume:%d, sts:%d", p_rsp->volume, p_rsp->status);
    return avrc_bld_ctrl_status_rsp((tAVRC_RSP *)p_rsp, p_pkt);
}


/*******************************************************************************
**
** Function         avrc_bld_set_browsed_player_rsp
**
** Description      This function builds the Set Browsed Player response.
**
**                  This message goes through the Browsing channel and is
**                  valid only when AVCT_BROWSE_INCLUDED compile option is TRUE
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
#if (AVCT_BROWSE_INCLUDED == TRUE)
static tAVRC_STS avrc_bld_set_browsed_player_rsp (tAVRC_SET_BR_PLAYER_RSP *p_rsp, BT_HDR *p_pkt)
{
    UINT8   *p_data, *p_start;
    UINT8   *p_len, xx;
    UINT16  len;
    tAVRC_NAME  *p_folders = p_rsp->p_folders;
    UINT16  len_left;
    UINT8   *p_num;
    UINT16  mtu;

    AVRC_TRACE_API0("avrc_bld_set_browsed_player_rsp");
    /* make sure the given GKI buffer can accomodate this response */
    len_left = GKI_get_buf_size(p_pkt) - BT_HDR_SIZE;
    p_data = (UINT8 *)(p_pkt + 1);
    BE_STREAM_TO_UINT16 (mtu, p_data);
    if (len_left > mtu)
    {
        len_left = mtu;
    }
    len_left = len_left - p_pkt->offset - p_pkt->len;
    AVRC_TRACE_DEBUG2("len_left:%d, mtu:%d ", len_left, mtu);

    /* get the existing length, if any, and also the num attributes */
    p_start = (UINT8 *)(p_pkt + 1) + p_pkt->offset;
    p_data = p_len = p_start + 1; /* pdu */

    /* the existing len */
    BE_STREAM_TO_UINT16(len, p_data);
    p_num = p_data + 9;
    if (len == 0)
    {
        /* first time initialize the attribute count */
        UINT8_TO_BE_STREAM(p_data, p_rsp->status);
        UINT16_TO_BE_STREAM(p_data, p_rsp->uid_counter);
        UINT32_TO_BE_STREAM(p_data, p_rsp->num_items);
        UINT16_TO_BE_STREAM(p_data, p_rsp->charset_id);
        *p_num = 0;
        p_data++;
        len = 10;
        len_left -= 12; /* assuming that we would never use a GKI buffer that is too small for headers */
    }
    else
    {
        p_data = p_start + p_pkt->len;
    }

    for (xx=0; (xx<p_rsp->folder_depth) && (len_left>(p_folders[xx].str_len + 2)); xx++)
    {
        (*p_num)++;
        UINT16_TO_BE_STREAM(p_data, p_folders[xx].str_len);
        ARRAY_TO_BE_STREAM(p_data, p_folders[xx].p_str, p_folders[xx].str_len);
        len += (p_folders[xx].str_len + 2);
    }
    UINT16_TO_BE_STREAM(p_len, len);
    p_pkt->len = (p_data - p_start);
    return AVRC_STS_NO_ERROR;
}
#endif


/*******************************************************************************
**
** Function         avrc_bld_get_folder_items_rsp
**
** Description      This function builds the Get Folder Items response.
**                  The error code is returned in *p_status.
**                  AVRC_STS_INTERNAL_ERR means no GKI buffers.
**                  Try again later or with smaller item_count
**
**                  This message goes through the Browsing channel and is
**                  valid only when AVCT_BROWSE_INCLUDED compile option is TRUE
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  AVRC_STS_INTERNAL_ERR, if the given GKI buffer does not have enough room
**                  Otherwise, the error code.
**
*******************************************************************************/
#if (AVCT_BROWSE_INCLUDED == TRUE)
static tAVRC_STS avrc_bld_get_folder_items_rsp (tAVRC_GET_ITEMS_RSP *p_rsp, BT_HDR *p_pkt)
{
    UINT8   *p_data, *p_start;
    UINT8   *p_len, xx;
    UINT16  len;
    UINT16  item_len;
    UINT8   *p_item_len, yy;
    tAVRC_ITEM_PLAYER   *p_player;
    tAVRC_ITEM_FOLDER   *p_folder;
    tAVRC_ITEM_MEDIA    *p_media;
    tAVRC_ATTR_ENTRY    *p_attr;
    tAVRC_ITEM          *p_item_list = p_rsp->p_item_list;
    tAVRC_STS           status = AVRC_STS_NO_ERROR;
    UINT16  len_left;
    UINT8   *p_num, *p;
    UINT8   *p_item_start, *p_attr_count;
    UINT16  item_count;
    UINT16  mtu;

    AVRC_TRACE_API0("avrc_bld_get_folder_items_rsp");
    /* make sure the given GKI buffer can accomodate this response */
    len_left = GKI_get_buf_size(p_pkt) - BT_HDR_SIZE;
    p = (UINT8 *)(p_pkt + 1);
    BE_STREAM_TO_UINT16 (mtu, p);
    if (len_left > mtu)
        len_left = mtu;
    len_left = len_left - p_pkt->offset - p_pkt->len;

    /* get the existing length, if any, and also the num attributes */
    p_start = (UINT8 *)(p_pkt + 1) + p_pkt->offset;
    p_data = p_len = p_start + 1; /* pdu */

    /* the existing len */
    BE_STREAM_TO_UINT16(len, p_data);
    p_num = p_data + 3;
    if (len == 0)
    {
        /* first time initialize the attribute count */
        UINT8_TO_BE_STREAM(p_data, p_rsp->status);
        UINT16_TO_BE_STREAM(p_data, p_rsp->uid_counter);
        item_count = 0;
        p_data+= 2;
        len = 5;
        len_left -= 5;
    }
    else
    {
        p_data = p_start + p_pkt->len;
        p = p_num;
        BE_STREAM_TO_UINT16 (item_count, p);
    }
    AVRC_TRACE_DEBUG3("len:%d, len_left:%d, num:%d", len, len_left, item_count);

    /* min len required = item_type(1) + item len(2) + min item (14) = 17 */
    for (xx=0; xx<p_rsp->item_count && len_left > 17; xx++)
    {
        p_item_start = p_data;
        UINT8_TO_BE_STREAM(p_data, p_item_list[xx].item_type);
        /* variable item lenth - save the location to add length */
        p_item_len = p_data;
        p_data += 2;
        item_len = 0;
        len_left -= 3; /* item_type(1) + item len(2) */
        switch (p_item_list[xx].item_type)
        {
        case AVRC_ITEM_PLAYER:
            /* min len required: 2 + 1 + 4 + 1 + 16 + 2 + 2 = 30 + str_len */
            p_player = &p_item_list[xx].u.player;
            item_len = AVRC_FEATURE_MASK_SIZE + p_player->name.str_len + 12;
            if ((len_left > item_len) &&
                p_player->name.p_str &&
               (p_player->major_type & AVRC_MJ_TYPE_INVALID) == 0 &&
               (p_player->sub_type & AVRC_SUB_TYPE_INVALID) == 0 &&
               (p_player->play_status <= AVRC_PLAYSTATE_REV_SEEK || p_player->play_status == AVRC_PLAYSTATE_ERROR) )
            {
                UINT16_TO_BE_STREAM(p_data, p_player->player_id);
                UINT8_TO_BE_STREAM(p_data, p_player->major_type);
                UINT32_TO_BE_STREAM(p_data, p_player->sub_type);
                UINT8_TO_BE_STREAM(p_data, p_player->play_status);
                ARRAY_TO_BE_STREAM(p_data, p_player->features, AVRC_FEATURE_MASK_SIZE);
                UINT16_TO_BE_STREAM(p_data, p_player->name.charset_id);
                UINT16_TO_BE_STREAM(p_data, p_player->name.str_len);
                ARRAY_TO_BE_STREAM(p_data, p_player->name.p_str, p_player->name.str_len);
            }
            else
            {
                p_data = p_item_start;
            }
            break;

        case AVRC_ITEM_FOLDER:
            /* min len required: 8 + 1 + 1 + 2 + 2 = 14 + str_len */
            p_folder = &p_item_list[xx].u.folder;
            item_len = AVRC_UID_SIZE + p_folder->name.str_len + 6;
            if ((len_left > item_len) &&
                p_folder->name.p_str &&
                p_folder->type <= AVRC_FOLDER_TYPE_YEARS &&
                p_folder->playable <= TRUE)
            {
                ARRAY_TO_BE_STREAM(p_data, p_folder->uid, AVRC_UID_SIZE);
                UINT8_TO_BE_STREAM(p_data, p_folder->type);
                UINT8_TO_BE_STREAM(p_data, p_folder->playable);
                UINT16_TO_BE_STREAM(p_data, p_folder->name.charset_id);
                UINT16_TO_BE_STREAM(p_data, p_folder->name.str_len);
                ARRAY_TO_BE_STREAM(p_data, p_folder->name.p_str, p_folder->name.str_len);
            }
            else
            {
                p_data = p_item_start;
            }
            break;

        case AVRC_ITEM_MEDIA:
            /* min len required: 8 + 1 + 2 + 2 + 1 = 14 + str_len */
            p_media = &p_item_list[xx].u.media;
            item_len = AVRC_UID_SIZE + p_media->name.str_len + 6;
            if ((len_left > item_len) &&
                p_media->name.p_str &&
                p_media->type <= AVRC_MEDIA_TYPE_VIDEO)
            {
                ARRAY_TO_BE_STREAM(p_data, p_media->uid, AVRC_UID_SIZE);
                UINT8_TO_BE_STREAM(p_data, p_media->type);
                UINT16_TO_BE_STREAM(p_data, p_media->name.charset_id);
                UINT16_TO_BE_STREAM(p_data, p_media->name.str_len);
                ARRAY_TO_BE_STREAM(p_data, p_media->name.p_str, p_media->name.str_len);
                p_attr_count = p_data++;
                *p_attr_count = 0;
                len_left -= item_len;
                if (p_media->attr_count>0)
                {
                    p_attr = p_media->p_attr_list;
                    for (yy=0; yy<p_media->attr_count && len_left > 8; yy++)
                    {
                        if (p_attr[yy].name.p_str &&
                            AVRC_IS_VALID_MEDIA_ATTRIBUTE(p_attr[yy].attr_id) &&
                            (len_left >= (p_attr[yy].name.str_len + 8)) )
                        {
                            (*p_attr_count) ++;
                            UINT32_TO_BE_STREAM(p_data, p_attr[yy].attr_id);
                            UINT16_TO_BE_STREAM(p_data, p_attr[yy].name.charset_id);
                            UINT16_TO_BE_STREAM(p_data, p_attr[yy].name.str_len);
                            ARRAY_TO_BE_STREAM(p_data, p_attr[yy].name.p_str, p_attr[yy].name.str_len);
                            item_len += (p_attr[yy].name.str_len + 8);
                            len_left -= (p_attr[yy].name.str_len + 8);
                        }
                    }
                }
            }
            else
            {
                p_data = p_item_start;
            }
            break;
        } /* switch item_type */

        if (p_item_start != p_data)
        {
            /* successfully added the item */
            item_count++;
            /* fill in variable item lenth */
            UINT16_TO_BE_STREAM(p_item_len, item_len);
        }
        else
        {
            /* some item is not added properly - set an error status */
            if (len_left > item_len)
                status = AVRC_STS_INTERNAL_ERR;
            else
                status = AVRC_STS_BAD_PARAM;
        }

        len += item_len;
        len += 3; /* the item_type(1) and item_len(2) */
        AVRC_TRACE_DEBUG4("len:%d, len_left:%d, num:%d, item_len:%d", len, len_left, item_count, item_len);
    } /* for item_count */

    UINT16_TO_BE_STREAM(p_num, item_count);
    UINT16_TO_BE_STREAM(p_len, len);
    p_pkt->len = (p_data - p_start);

    if (p_rsp->item_count != xx)
    {
        p_rsp->item_count = xx;
        if  (status == AVRC_STS_NO_ERROR)
            status = AVRC_STS_INTERNAL_ERR;
    }

    return status;
}
#endif


/*******************************************************************************
**
** Function         avrc_bld_change_path_rsp
**
** Description      This function builds the Change Path response.
**
**                  This message goes through the Browsing channel and is
**                  valid only when AVCT_BROWSE_INCLUDED compile option is TRUE
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
#if (AVCT_BROWSE_INCLUDED == TRUE)
static tAVRC_STS avrc_bld_change_path_rsp (tAVRC_CHG_PATH_RSP *p_rsp, BT_HDR *p_pkt)
{
    UINT8   *p_data, *p_start;

    /* get the existing length, if any, and also the num attributes */
    p_start = (UINT8 *)(p_pkt + 1) + p_pkt->offset;
    p_data = p_start + 1; /* pdu */
    /* add fixed lenth - status(1) + num_items(4) */
    UINT16_TO_BE_STREAM(p_data, 5);
    UINT8_TO_BE_STREAM(p_data, p_rsp->status);
    UINT32_TO_BE_STREAM(p_data, p_rsp->num_items);
    p_pkt->len = (p_data - p_start);
    return AVRC_STS_NO_ERROR;
}
#endif


/*******************************************************************************
**
** Function         avrc_bld_get_item_attrs_rsp
**
** Description      This function builds the Get Item Attributes response.
**
**                  This message goes through the Browsing channel and is
**                  valid only when AVCT_BROWSE_INCLUDED compile option is TRUE
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  AVRC_STS_INTERNAL_ERR, if the given GKI buffer does not have enough room
**                  Otherwise, the error code.
**
*******************************************************************************/
#if (AVCT_BROWSE_INCLUDED == TRUE)
static tAVRC_STS avrc_bld_get_item_attrs_rsp (tAVRC_GET_ATTRS_RSP *p_rsp, BT_HDR *p_pkt)
{
    UINT8   *p_data, *p_start;
    UINT8   *p_len, xx;
    UINT16  len, len_left;
    UINT8   *p_num;
    UINT16  mtu;

    AVRC_TRACE_API0("avrc_bld_get_item_attrs_rsp");
    /* calculate the GKI buffer size needed and validate the parameters */
    if (!p_rsp->p_attr_list)
    {
        AVRC_TRACE_ERROR0("NULL p_attr_list");
        return AVRC_STS_BAD_PARAM;
    }

    /* check the length before adding the attr to the message */
    len = 2;
    for (xx=0; xx<p_rsp->attr_count; xx++)
    {
        if(p_rsp->p_attr_list[xx].name.p_str == 0 ||
            !AVRC_IS_VALID_MEDIA_ATTRIBUTE(p_rsp->p_attr_list[xx].attr_id))
        {
            AVRC_TRACE_ERROR2("[%d] NULL p_attr_list str or bad attr_id:%d", xx, p_rsp->p_attr_list[xx].attr_id);
            return AVRC_STS_BAD_PARAM;
        }
        len += (p_rsp->p_attr_list[xx].name.str_len + 8);
    }
    len_left = GKI_get_buf_size(p_pkt) - BT_HDR_SIZE;
    p_data = (UINT8 *)(p_pkt + 1);
    BE_STREAM_TO_UINT16 (mtu, p_data);
    if (len_left > mtu)
    {
        len_left = mtu;
    }
    len_left = len_left - p_pkt->offset - p_pkt->len;

    AVRC_TRACE_DEBUG3("len_left:%d, mtu:%d len needed:%d", len_left, mtu, len);
    if (len_left < 11) /* 11 is 4/attr_id + 2/charset_id + 2/str_len + 3/first timer/attr count & len */
    {
        return AVRC_STS_INTERNAL_ERR;
    }
    if (len > len_left)
    {
        AVRC_TRACE_ERROR0("The GKI buffer does not have enough room to hold the given data.");
    }

    /* get the existing length, if any, and also the num attributes */
    p_start = (UINT8 *)(p_pkt + 1) + p_pkt->offset;
    p_data = p_len = p_start + 1; /* pdu */

    /* the existing len */
    BE_STREAM_TO_UINT16(len, p_data);
    p_num = p_data + 1;
    if (len == 0)
    {
        /* first time initialize the attribute count */
        UINT8_TO_BE_STREAM(p_data, p_rsp->status);
        *p_num = 0;
        p_data++;
        len = 2;
        len_left -= 3;
    }
    else
    {
        p_data = p_start + p_pkt->len;
    }


    for (xx=0; (xx<p_rsp->attr_count) && (len_left>9); xx++)
    {
        (*p_num)++;
        UINT32_TO_BE_STREAM(p_data, p_rsp->p_attr_list[xx].attr_id);
        UINT16_TO_BE_STREAM(p_data, p_rsp->p_attr_list[xx].name.charset_id);
        UINT16_TO_BE_STREAM(p_data, p_rsp->p_attr_list[xx].name.str_len);
        len_left -= 8;
        if (p_rsp->p_attr_list[xx].name.str_len > len_left)
            p_rsp->p_attr_list[xx].name.str_len = len_left;
        ARRAY_TO_BE_STREAM(p_data, p_rsp->p_attr_list[xx].name.p_str, p_rsp->p_attr_list[xx].name.str_len);
        len_left -= p_rsp->p_attr_list[xx].name.str_len;
        len += (p_rsp->p_attr_list[xx].name.str_len + 8);
    }

    UINT16_TO_BE_STREAM(p_len, len);
    p_pkt->len = (p_data - p_start);
    return AVRC_STS_NO_ERROR;
}
#endif


/*******************************************************************************
**
** Function         avrc_bld_search_rsp
**
** Description      This function builds the Search response.
**
**                  This message goes through the Browsing channel and is
**                  valid only when AVCT_BROWSE_INCLUDED compile option is TRUE
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
#if (AVCT_BROWSE_INCLUDED == TRUE)
static tAVRC_STS avrc_bld_search_rsp (tAVRC_SEARCH_RSP *p_rsp, BT_HDR *p_pkt)
{
    UINT8   *p_data, *p_start, *p_len;

    AVRC_TRACE_API0("avrc_bld_search_rsp");
    /* get the existing length, if any, and also the num attributes */
    p_start = (UINT8 *)(p_pkt + 1) + p_pkt->offset;
    p_data = p_len = p_start + 1; /* pdu */

    /* add fixed lenth - status(1) + uid_counter(2) + num_items(4) */
    UINT16_TO_BE_STREAM(p_data, 7);
    UINT8_TO_BE_STREAM(p_data, p_rsp->status);
    UINT16_TO_BE_STREAM(p_data, p_rsp->uid_counter);
    UINT32_TO_BE_STREAM(p_data, p_rsp->num_items);
    p_pkt->len = (p_data - p_start);
    return AVRC_STS_NO_ERROR;
}
#endif


/*******************************************************************************
**
** Function         avrc_bld_play_item_rsp
**
** Description      This function builds the Play Item response.
**                  
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_play_item_rsp (tAVRC_RSP *p_rsp, BT_HDR *p_pkt)
{
    AVRC_TRACE_API0("avrc_bld_play_item_rsp");
    return avrc_bld_ctrl_status_rsp(p_rsp, p_pkt);
}


/*******************************************************************************
**
** Function         avrc_bld_add_to_now_playing_rsp
**
** Description      This function builds the Add to Now Playing response.
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
static tAVRC_STS avrc_bld_add_to_now_playing_rsp (tAVRC_RSP *p_rsp, BT_HDR *p_pkt)
{
    AVRC_TRACE_API0("avrc_bld_add_to_now_playing_rsp");
    return avrc_bld_ctrl_status_rsp(p_rsp, p_pkt);
}

#endif /* AVRC_ADV_CTRL_INCLUDED=TRUE */

/*******************************************************************************
**
** Function         avrc_bld_init_rsp_buffer
**
** Description      This function initializes the response buffer based on PDU
**
** Returns          NULL, if no GKI buffer or failure to build the message.
**                  Otherwise, the GKI buffer that contains the initialized message.
**
*******************************************************************************/
static BT_HDR *avrc_bld_init_rsp_buffer(tAVRC_RESPONSE *p_rsp)
{
    UINT16 offset, chnl = AVCT_DATA_CTRL, len=AVRC_META_CMD_POOL_SIZE;
    BT_HDR *p_pkt=NULL;
    UINT8  opcode = avrc_opcode_from_pdu(p_rsp->pdu);

    AVRC_TRACE_API3("avrc_bld_init_rsp_buffer: pdu=%x, opcode=%x/%x", p_rsp->pdu, opcode, p_rsp->rsp.opcode);
    if (opcode != p_rsp->rsp.opcode && p_rsp->rsp.status != AVRC_STS_NO_ERROR && avrc_is_valid_opcode(p_rsp->rsp.opcode))
    {
        opcode = p_rsp->rsp.opcode;
        AVRC_TRACE_API1("opcode=%x", opcode);
    }

    switch (opcode)
    {
#if (AVCT_BROWSE_INCLUDED == TRUE)
    case AVRC_OP_BROWSE:
        chnl    = AVCT_DATA_BROWSE;
        offset  = AVCT_BROWSE_OFFSET;
        len     = AVRC_BROWSE_POOL_SIZE;
        break;
#endif /* AVCT_BROWSE_INCLUDED */

    case AVRC_OP_PASS_THRU:
        offset  = AVRC_MSG_PASS_THRU_OFFSET;
        break;

    case AVRC_OP_VENDOR:
        offset  = AVRC_MSG_VENDOR_OFFSET;
        if (p_rsp->pdu == AVRC_PDU_GET_ELEMENT_ATTR)
            len     = AVRC_BROWSE_POOL_SIZE;
        break;
    }

    /* allocate and initialize the buffer */
    p_pkt = (BT_HDR *)GKI_getbuf(len);
    if (p_pkt)
    {
        UINT8 *p_data, *p_start;

        p_pkt->layer_specific = chnl;
        p_pkt->event    = opcode;
        p_pkt->offset   = offset;
        p_data = (UINT8 *)(p_pkt + 1) + p_pkt->offset;
        p_start = p_data;

        /* pass thru - group navigation - has a two byte op_id, so dont do it here */
        if (opcode != AVRC_OP_PASS_THRU)
            *p_data++ = p_rsp->pdu;

        switch (opcode)
        {
        case AVRC_OP_VENDOR:
            /* reserved 0, packet_type 0 */
            UINT8_TO_BE_STREAM(p_data, 0);
            /* continue to the next "case to add length */
#if (AVCT_BROWSE_INCLUDED == TRUE)
        case AVRC_OP_BROWSE:
#endif
            /* add fixed lenth - 0 */
            UINT16_TO_BE_STREAM(p_data, 0);
            break;
        }

        p_pkt->len = (p_data - p_start);
    }
    p_rsp->rsp.opcode = opcode;
    return p_pkt;
}

/*******************************************************************************
**
** Function         AVRC_BldResponse
**
** Description      This function builds the given AVRCP response to the given 
**                  GKI buffer
**
** Returns          AVRC_STS_NO_ERROR, if the response is built successfully
**                  Otherwise, the error code.
**
*******************************************************************************/
tAVRC_STS AVRC_BldResponse( UINT8 handle, tAVRC_RESPONSE *p_rsp, BT_HDR **pp_pkt)
{
    tAVRC_STS status = AVRC_STS_BAD_PARAM;
    BT_HDR *p_pkt;
    BOOLEAN alloc = FALSE;
#if ((AVRC_ADV_CTRL_INCLUDED == TRUE) && (AVCT_BROWSE_INCLUDED == TRUE))
    UINT8   *p;
    UINT16  peer_mtu;
#endif

    if (!p_rsp || !pp_pkt)
    {
        AVRC_TRACE_API2("AVRC_BldResponse. Invalid parameters passed. p_rsp=%p, pp_pkt=%p", p_rsp, pp_pkt);
        return AVRC_STS_BAD_PARAM;
    }

    if (*pp_pkt == NULL)
    {
        if ((*pp_pkt = avrc_bld_init_rsp_buffer(p_rsp)) == NULL)
        {
            AVRC_TRACE_API0("AVRC_BldResponse: Failed to initialize response buffer");
            return AVRC_STS_INTERNAL_ERR;
        }
#if ((AVRC_ADV_CTRL_INCLUDED == TRUE) && (AVCT_BROWSE_INCLUDED == TRUE))
        if ((*pp_pkt)->layer_specific == AVCT_DATA_BROWSE)
        {
            p = (UINT8 *)((*pp_pkt) + 1);
            peer_mtu = AVCT_GetBrowseMtu(handle) - AVCT_HDR_LEN_SINGLE;
            UINT16_TO_BE_STREAM(p, peer_mtu);
        }
#endif
        alloc = TRUE;
    }
    status = AVRC_STS_NO_ERROR;
    p_pkt = *pp_pkt;

    AVRC_TRACE_API2("AVRC_BldResponse: pdu=%x status=%x", p_rsp->rsp.pdu, p_rsp->rsp.status);
    if (p_rsp->rsp.status != AVRC_STS_NO_ERROR)
    {
        return( avrc_bld_rejected_rsp(&p_rsp->rsp, p_pkt) );
    }

    switch (p_rsp->pdu)
    {
    case AVRC_PDU_NEXT_GROUP:
    case AVRC_PDU_PREV_GROUP:
        status = avrc_bld_group_navigation_rsp(p_rsp->pdu, p_pkt);
        break;

    case AVRC_PDU_GET_CAPABILITIES:
        status = avrc_bld_get_capability_rsp(&p_rsp->get_caps, p_pkt);
        break;

    case AVRC_PDU_LIST_PLAYER_APP_ATTR:
        status = avrc_bld_list_app_settings_attr_rsp(&p_rsp->list_app_attr, p_pkt);
        break;

    case AVRC_PDU_LIST_PLAYER_APP_VALUES:
        status = avrc_bld_list_app_settings_values_rsp(&p_rsp->list_app_values, p_pkt);
        break;

    case AVRC_PDU_GET_CUR_PLAYER_APP_VALUE:
        status = avrc_bld_get_cur_app_setting_value_rsp(&p_rsp->get_cur_app_val, p_pkt);
        break;

    case AVRC_PDU_SET_PLAYER_APP_VALUE:
        status = avrc_bld_set_app_setting_value_rsp(&p_rsp->set_app_val, p_pkt);
        break;

    case AVRC_PDU_GET_PLAYER_APP_ATTR_TEXT:
        status = avrc_bld_get_app_setting_attr_text_rsp(&p_rsp->get_app_attr_txt, p_pkt);
        break;

    case AVRC_PDU_GET_PLAYER_APP_VALUE_TEXT:
        status = avrc_bld_get_app_setting_value_text_rsp(&p_rsp->get_app_val_txt, p_pkt);
        break;

    case AVRC_PDU_INFORM_DISPLAY_CHARSET:
        status = avrc_bld_inform_charset_rsp(&p_rsp->inform_charset, p_pkt);
        break;

    case AVRC_PDU_INFORM_BATTERY_STAT_OF_CT:
        status = avrc_bld_inform_battery_status_rsp(&p_rsp->inform_battery_status, p_pkt);
        break;

    case AVRC_PDU_GET_ELEMENT_ATTR:
        status = avrc_bld_get_elem_attrs_rsp(&p_rsp->get_elem_attrs, p_pkt);
        break;

    case AVRC_PDU_GET_PLAY_STATUS:
        status = avrc_bld_get_play_status_rsp(&p_rsp->get_play_status, p_pkt);
        break;

    case AVRC_PDU_REGISTER_NOTIFICATION:
        status = avrc_bld_notify_rsp(&p_rsp->reg_notif, p_pkt);
        break;

    case AVRC_PDU_REQUEST_CONTINUATION_RSP:     /*        0x40 */
        status = avrc_bld_next_rsp(&p_rsp->continu, p_pkt);
        break;

    case AVRC_PDU_ABORT_CONTINUATION_RSP:       /*          0x41 */
        status = avrc_bld_next_rsp(&p_rsp->abort, p_pkt);
        break;

#if (AVRC_ADV_CTRL_INCLUDED == TRUE)
    case AVRC_PDU_SET_ABSOLUTE_VOLUME:         /* 0x50 */
        status = avrc_bld_set_abs_volume_rsp(&p_rsp->volume, p_pkt);
        break;

    case AVRC_PDU_SET_ADDRESSED_PLAYER:        /* 0x60 */    
        status = avrc_bld_set_addr_player_rsp(&p_rsp->addr_player, p_pkt);
        break;

    case AVRC_PDU_PLAY_ITEM:                   /* 0x74 */    
        status = avrc_bld_play_item_rsp(&p_rsp->play_item, p_pkt);
        break;

    case AVRC_PDU_ADD_TO_NOW_PLAYING:          /* 0x90 */    
        status = avrc_bld_add_to_now_playing_rsp(&p_rsp->add_to_play, p_pkt);
        break;

#if (AVCT_BROWSE_INCLUDED == TRUE)
    case AVRC_PDU_SET_BROWSED_PLAYER:          /* 0x70 */    
        status = avrc_bld_set_browsed_player_rsp(&p_rsp->br_player, p_pkt);
        break;

    case AVRC_PDU_GET_FOLDER_ITEMS:            /* 0x71 */   
        status = avrc_bld_get_folder_items_rsp(&p_rsp->get_items, p_pkt);
        break;

    case AVRC_PDU_CHANGE_PATH:                 /* 0x72 */    
        status = avrc_bld_change_path_rsp(&p_rsp->chg_path, p_pkt);
        break;

    case AVRC_PDU_GET_ITEM_ATTRIBUTES:         /* 0x73 */    
        status = avrc_bld_get_item_attrs_rsp(&p_rsp->get_attrs, p_pkt);
        break;

    case AVRC_PDU_SEARCH:                      /* 0x80 */    
        status = avrc_bld_search_rsp(&p_rsp->search, p_pkt);
        break;
#endif
#endif
    }

    if (alloc && (status != AVRC_STS_NO_ERROR) )
    {
        GKI_freebuf(p_pkt);
        *pp_pkt = NULL;
    }
    AVRC_TRACE_API1("AVRC_BldResponse: returning %d", status);
    return status;
}

#endif /* (AVRC_METADATA_INCLUDED == TRUE)*/