/*
 * Copyright (C) 2011 Teluu Inc. (http://www.teluu.com)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include <pjmedia/vid_stream.h>
#include <pjmedia/sdp_neg.h>
#include <pjmedia/stream_common.h>
#include <pj/ctype.h>
#include <pj/rand.h>

#if defined(PJMEDIA_HAS_VIDEO) && (PJMEDIA_HAS_VIDEO != 0)

static const pj_str_t ID_IN = { "IN", 2 };
static const pj_str_t ID_IP4 = { "IP4", 3};
static const pj_str_t ID_IP6 = { "IP6", 3};
//static const pj_str_t ID_SDP_NAME = { "pjmedia", 7 };
static const pj_str_t ID_RTPMAP = { "rtpmap", 6 };

/*
 * Internal function for collecting codec info and param from the SDP media.
 */
static pj_status_t get_video_codec_info_param(pjmedia_vid_stream_info *si,
                                              pj_pool_t *pool,
                                              pjmedia_vid_codec_mgr *mgr,
                                              const pjmedia_sdp_media *local_m,
                                              const pjmedia_sdp_media *rem_m)
{
    unsigned pt = 0;
    const pjmedia_vid_codec_info *p_info;
    pj_status_t status;

    pt = pj_strtoul(&local_m->desc.fmt[0]);

    /* Get payload type for receiving direction */
    si->rx_pt = pt;

    /* Get codec info and payload type for transmitting direction. */
    if (pt < 96) {
        /* For static payload types, get the codec info from codec manager. */
        status = pjmedia_vid_codec_mgr_get_codec_info(mgr, pt, &p_info);
        if (status != PJ_SUCCESS)
            return status;

        si->codec_info = *p_info;

        /* Get payload type for transmitting direction.
         * For static payload type, pt's are symetric.
         */
        si->tx_pt = pt;
    } else {
        const pjmedia_sdp_attr *attr;
        pjmedia_sdp_rtpmap *rtpmap;
        pjmedia_codec_id codec_id;
        pj_str_t codec_id_st;
        unsigned i;

        /* Determine payload type for outgoing channel, by finding
         * dynamic payload type in remote SDP that matches the answer.
         */
        si->tx_pt = 0xFFFF;
        for (i=0; i<rem_m->desc.fmt_count; ++i) {
            if (pjmedia_sdp_neg_fmt_match(NULL,
                                          (pjmedia_sdp_media*)local_m, 0,
                                          (pjmedia_sdp_media*)rem_m, i, 0) ==
                PJ_SUCCESS)
            {
                /* Found matched codec. */
                si->tx_pt = pj_strtoul(&rem_m->desc.fmt[i]);
                break;
            }
        }

        if (si->tx_pt == 0xFFFF)
            return PJMEDIA_EMISSINGRTPMAP;

        /* For dynamic payload types, get codec name from the rtpmap */
        attr = pjmedia_sdp_media_find_attr(local_m, &ID_RTPMAP,
                                           &local_m->desc.fmt[0]);
        if (attr == NULL)
            return PJMEDIA_EMISSINGRTPMAP;

        status = pjmedia_sdp_attr_to_rtpmap(pool, attr, &rtpmap);
        if (status != PJ_SUCCESS)
            return status;

        /* Then get the codec info from the codec manager */
        pj_ansi_snprintf(codec_id, sizeof(codec_id), "%.*s/",
                         (int)rtpmap->enc_name.slen, rtpmap->enc_name.ptr);
        codec_id_st = pj_str(codec_id);
        i = 1;
        status = pjmedia_vid_codec_mgr_find_codecs_by_id(mgr, &codec_id_st,
                                                         &i, &p_info, NULL);
        if (status != PJ_SUCCESS)
            return status;

        si->codec_info = *p_info;
    }


    /* Request for codec with the correct packing for streaming */
    si->codec_info.packings = PJMEDIA_VID_PACKING_PACKETS;

    /* Now that we have codec info, get the codec param. */
    si->codec_param = PJ_POOL_ALLOC_T(pool, pjmedia_vid_codec_param);
    status = pjmedia_vid_codec_mgr_get_default_param(mgr,
                                                     &si->codec_info,
                                                     si->codec_param);

    /* Adjust encoding bitrate, if higher than remote preference. The remote
     * bitrate preference is read from SDP "b=TIAS" line in media level.
     */
    if ((si->dir & PJMEDIA_DIR_ENCODING) && rem_m->bandw_count) {
        unsigned i, bandw = 0;

        for (i = 0; i < rem_m->bandw_count; ++i) {
            const pj_str_t STR_BANDW_MODIFIER_TIAS = { "TIAS", 4 };
            if (!pj_stricmp(&rem_m->bandw[i]->modifier,
                &STR_BANDW_MODIFIER_TIAS))
            {
                bandw = rem_m->bandw[i]->value;
                break;
            }
        }

        if (bandw) {
            pjmedia_video_format_detail *enc_vfd;
            enc_vfd = pjmedia_format_get_video_format_detail(
                                        &si->codec_param->enc_fmt, PJ_TRUE);
            if (!enc_vfd->avg_bps || enc_vfd->avg_bps > bandw)
                enc_vfd->avg_bps = bandw * 3 / 4;
            if (!enc_vfd->max_bps || enc_vfd->max_bps > bandw)
                enc_vfd->max_bps = bandw;
        }
    }

    /* Get remote fmtp for our encoder. */
    pjmedia_stream_info_parse_fmtp(pool, rem_m, si->tx_pt,
                                   &si->codec_param->enc_fmtp);

    /* Get local fmtp for our decoder. */
    pjmedia_stream_info_parse_fmtp(pool, local_m, si->rx_pt,
                                   &si->codec_param->dec_fmtp);

    /* When direction is NONE (it means SDP negotiation has failed) we don't
     * need to return a failure here, as returning failure will cause
     * the whole SDP to be rejected. See ticket #:
     *  http://
     *
     * Thanks Alain Totouom
     */
    if (status != PJ_SUCCESS && si->dir != PJMEDIA_DIR_NONE)
        return status;

    return PJ_SUCCESS;
}



/*
 * Create stream info from SDP media line.
 */
PJ_DEF(pj_status_t) pjmedia_vid_stream_info_from_sdp(
                                           pjmedia_vid_stream_info *si,
                                           pj_pool_t *pool,
                                           pjmedia_endpt *endpt,
                                           const pjmedia_sdp_session *local,
                                           const pjmedia_sdp_session *remote,
                                           unsigned stream_idx)
{
    const pj_str_t STR_INACTIVE = { "inactive", 8 };
    const pj_str_t STR_SENDONLY = { "sendonly", 8 };
    const pj_str_t STR_RECVONLY = { "recvonly", 8 };

    const pjmedia_sdp_attr *attr;
    const pjmedia_sdp_media *local_m;
    const pjmedia_sdp_media *rem_m;
    const pjmedia_sdp_conn *local_conn;
    const pjmedia_sdp_conn *rem_conn;
    int rem_af, local_af;
    unsigned i;
    pj_status_t status;

    PJ_UNUSED_ARG(endpt);

    /* Validate arguments: */
    PJ_ASSERT_RETURN(pool && si && local && remote, PJ_EINVAL);
    PJ_ASSERT_RETURN(stream_idx < local->media_count, PJ_EINVAL);
    PJ_ASSERT_RETURN(stream_idx < remote->media_count, PJ_EINVAL);

    /* Keep SDP shortcuts */
    local_m = local->media[stream_idx];
    rem_m = remote->media[stream_idx];

    local_conn = local_m->conn ? local_m->conn : local->conn;
    if (local_conn == NULL)
        return PJMEDIA_SDP_EMISSINGCONN;

    rem_conn = rem_m->conn ? rem_m->conn : remote->conn;
    if (rem_conn == NULL)
        return PJMEDIA_SDP_EMISSINGCONN;

    /* Media type must be video */
    if (pjmedia_get_type(&local_m->desc.media) != PJMEDIA_TYPE_VIDEO)
        return PJMEDIA_EINVALIMEDIATYPE;


    /* Reset: */

    pj_bzero(si, sizeof(*si));

    /* Media type: */
    si->type = PJMEDIA_TYPE_VIDEO;

    /* Transport protocol */

    /* At this point, transport type must be compatible,
     * the transport instance will do more validation later.
     */
    status = pjmedia_sdp_transport_cmp(&rem_m->desc.transport,
                                       &local_m->desc.transport);
    if (status != PJ_SUCCESS)
        return PJMEDIA_SDPNEG_EINVANSTP;

    /* Get the transport protocol */
    si->proto = pjmedia_sdp_transport_get_proto(&local_m->desc.transport);

    /* Return success if transport protocol is not RTP/AVP compatible */
    if (!PJMEDIA_TP_PROTO_HAS_FLAG(si->proto, PJMEDIA_TP_PROTO_RTP_AVP))
        return PJ_SUCCESS;


    /* Check address family in remote SDP */
    rem_af = pj_AF_UNSPEC();
    if (pj_stricmp(&rem_conn->net_type, &ID_IN)==0) {
        if (pj_stricmp(&rem_conn->addr_type, &ID_IP4)==0) {
            rem_af = pj_AF_INET();
        } else if (pj_stricmp(&rem_conn->addr_type, &ID_IP6)==0) {
            rem_af = pj_AF_INET6();
        }
    }

    if (rem_af==pj_AF_UNSPEC()) {
        /* Unsupported address family */
        return PJ_EAFNOTSUP;
    }

    /* Set remote address: */
    status = pj_sockaddr_init(rem_af, &si->rem_addr, &rem_conn->addr,
                              rem_m->desc.port);
    if (status != PJ_SUCCESS) {
        /* Invalid IP address. */
        return PJMEDIA_EINVALIDIP;
    }

    /* Check address family of local info */
    local_af = pj_AF_UNSPEC();
    if (pj_stricmp(&local_conn->net_type, &ID_IN)==0) {
        if (pj_stricmp(&local_conn->addr_type, &ID_IP4)==0) {
            local_af = pj_AF_INET();
        } else if (pj_stricmp(&local_conn->addr_type, &ID_IP6)==0) {
            local_af = pj_AF_INET6();
        }
    }

    if (local_af==pj_AF_UNSPEC()) {
        /* Unsupported address family */
        return PJ_SUCCESS;
    }

    /* Set remote address: */
    status = pj_sockaddr_init(local_af, &si->local_addr, &local_conn->addr,
                              local_m->desc.port);
    if (status != PJ_SUCCESS) {
        /* Invalid IP address. */
        return PJMEDIA_EINVALIDIP;
    }

    /* Local and remote address family must match, except when ICE is used
     * by both sides (see also ticket #1952).
     */
    if (local_af != rem_af) {
        const pj_str_t STR_ICE_CAND = { "candidate", 9 };
        if (pjmedia_sdp_media_find_attr(rem_m, &STR_ICE_CAND, NULL)==NULL ||
            pjmedia_sdp_media_find_attr(local_m, &STR_ICE_CAND, NULL)==NULL)
        {
            return PJ_EAFNOTSUP;
        }
    }

    /* Media direction: */

    if (local_m->desc.port == 0 ||
        pj_sockaddr_has_addr(&si->local_addr)==PJ_FALSE ||
        pj_sockaddr_has_addr(&si->rem_addr)==PJ_FALSE ||
        pjmedia_sdp_media_find_attr(local_m, &STR_INACTIVE, NULL)!=NULL)
    {
        /* Inactive stream. */

        si->dir = PJMEDIA_DIR_NONE;

    } else if (pjmedia_sdp_media_find_attr(local_m, &STR_SENDONLY, NULL)!=NULL) {

        /* Send only stream. */

        si->dir = PJMEDIA_DIR_ENCODING;

    } else if (pjmedia_sdp_media_find_attr(local_m, &STR_RECVONLY, NULL)!=NULL) {

        /* Recv only stream. */

        si->dir = PJMEDIA_DIR_DECODING;

    } else {

        /* Send and receive stream. */

        si->dir = PJMEDIA_DIR_ENCODING_DECODING;

    }

    /* No need to do anything else if stream is rejected */
    if (local_m->desc.port == 0) {
        return PJ_SUCCESS;
    }

    /* Check if "rtcp-mux" is present in the SDP. */
    attr = pjmedia_sdp_attr_find2(rem_m->attr_count, rem_m->attr,
                                  "rtcp-mux", NULL);
    if (attr)
        si->rtcp_mux = PJ_TRUE;

    /* If "rtcp" attribute is present in the SDP, set the RTCP address
     * from that attribute. Otherwise, calculate from RTP address.
     */
    attr = pjmedia_sdp_attr_find2(rem_m->attr_count, rem_m->attr,
                                  "rtcp", NULL);
    if (attr) {
        pjmedia_sdp_rtcp_attr rtcp;
        status = pjmedia_sdp_attr_get_rtcp(attr, &rtcp);
        if (status == PJ_SUCCESS) {
            if (rtcp.addr.slen) {
                pj_sockaddr_init(rem_af, &si->rem_rtcp, &rtcp.addr,
                                 (pj_uint16_t)rtcp.port);
            } else {
                pj_sockaddr_init(rem_af, &si->rem_rtcp, NULL,
                                 (pj_uint16_t)rtcp.port);
                pj_memcpy(pj_sockaddr_get_addr(&si->rem_rtcp),
                          pj_sockaddr_get_addr(&si->rem_addr),
                          pj_sockaddr_get_addr_len(&si->rem_addr));
            }
        }
    }

    if (!pj_sockaddr_has_addr(&si->rem_rtcp)) {
        int rtcp_port;

        pj_memcpy(&si->rem_rtcp, &si->rem_addr, sizeof(pj_sockaddr));
        rtcp_port = pj_sockaddr_get_port(&si->rem_addr) + 1;
        pj_sockaddr_set_port(&si->rem_rtcp, (pj_uint16_t)rtcp_port);
    }

    /* Check if "ssrc" attribute is present in the SDP. */
    for (i = 0; i < rem_m->attr_count; i++) {
        if (pj_strcmp2(&rem_m->attr[i]->name, "ssrc") == 0) {
            pjmedia_sdp_ssrc_attr ssrc;

            status = pjmedia_sdp_attr_get_ssrc(
                        (const pjmedia_sdp_attr *)rem_m->attr[i], &ssrc);
            if (status == PJ_SUCCESS) {
                si->has_rem_ssrc = PJ_TRUE;
                si->rem_ssrc = ssrc.ssrc;
                if (ssrc.cname.slen > 0) {
                    pj_strdup(pool, &si->rem_cname, &ssrc.cname);
                    break;
                }
            }
        }
    }

    /* Get codec info and param */
    status = get_video_codec_info_param(si, pool, NULL, local_m, rem_m);

    /* Leave SSRC to random. */
    si->ssrc = pj_rand();

    /* Set default jitter buffer parameter. */
    si->jb_init = si->jb_max = si->jb_min_pre = si->jb_max_pre = -1;

    /* Get local RTCP-FB info */
    status = pjmedia_rtcp_fb_decode_sdp2(pool, endpt, NULL, local, stream_idx,
                                         si->rx_pt, &si->loc_rtcp_fb);
    if (status != PJ_SUCCESS)
        return status;

    /* Get remote RTCP-FB info */
    status = pjmedia_rtcp_fb_decode_sdp2(pool, endpt, NULL, remote, stream_idx,
                                         si->tx_pt, &si->rem_rtcp_fb);
    if (status != PJ_SUCCESS)
        return status;

    return status;
}

#endif /* PJMEDIA_HAS_VIDEO */
