//
// Copyright (c) 2013-2024 The SRS Authors
//
// SPDX-License-Identifier: MIT
//

#include <srs_app_caster_flv.hpp>

#include <algorithm>
using namespace std;

#include <srs_app_config.hpp>
#include <srs_kernel_error.hpp>
#include <srs_kernel_log.hpp>
#include <srs_app_config.hpp>
#include <srs_app_pithy_print.hpp>
#include <srs_app_http_conn.hpp>
#include <srs_core_autofree.hpp>
#include <srs_kernel_flv.hpp>
#include <srs_protocol_rtmp_stack.hpp>
#include <srs_protocol_utility.hpp>
#include <srs_app_st.hpp>
#include <srs_app_utility.hpp>
#include <srs_protocol_amf0.hpp>
#include <srs_kernel_utility.hpp>
#include <srs_app_rtmp_conn.hpp>
#include <srs_protocol_utility.hpp>

#define SRS_HTTP_FLV_STREAM_BUFFER 4096

SrsHttpFlvListener::SrsHttpFlvListener()
{
    listener_ = new SrsTcpListener(this);
    caster_ = new SrsAppCasterFlv();
}

SrsHttpFlvListener::~SrsHttpFlvListener()
{
    srs_freep(caster_);
    srs_freep(listener_);
}

srs_error_t SrsHttpFlvListener::initialize(SrsConfDirective* c)
{
    srs_error_t err = srs_success;

    int port = _srs_config->get_stream_caster_listen(c);
    if (port <= 0) {
        return srs_error_new(ERROR_STREAM_CASTER_PORT, "invalid port=%d", port);
    }

    listener_->set_endpoint(srs_any_address_for_listener(), port)->set_label("PUSH-FLV");

    if ((err = caster_->initialize(c)) != srs_success) {
        return srs_error_wrap(err, "init caster port=%d", port);
    }

    return err;
}

srs_error_t SrsHttpFlvListener::listen()
{
    srs_error_t err = srs_success;

    if ((err = listener_->listen()) != srs_success) {
        return srs_error_wrap(err, "listen");
    }

    return err;
}

void SrsHttpFlvListener::close()
{
    listener_->close();
}

srs_error_t SrsHttpFlvListener::on_tcp_client(ISrsListener* listener, srs_netfd_t stfd)
{
    srs_error_t err = caster_->on_tcp_client(listener, stfd);
    if (err != srs_success) {
        srs_warn("accept client failed, err is %s", srs_error_desc(err).c_str());
        srs_freep(err);
    }

    return err;
}

SrsAppCasterFlv::SrsAppCasterFlv()
{
    http_mux = new SrsHttpServeMux();
    manager = new SrsResourceManager("CFLV");
}

SrsAppCasterFlv::~SrsAppCasterFlv()
{
    srs_freep(http_mux);
    srs_freep(manager);
}

srs_error_t SrsAppCasterFlv::initialize(SrsConfDirective* c)
{
    srs_error_t err = srs_success;

    output = _srs_config->get_stream_caster_output(c);
    
    if ((err = http_mux->handle("/", this)) != srs_success) {
        return srs_error_wrap(err, "handle root");
    }
    
    if ((err = manager->start()) != srs_success) {
        return srs_error_wrap(err, "start manager");
    }
    
    return err;
}

srs_error_t SrsAppCasterFlv::on_tcp_client(ISrsListener* listener, srs_netfd_t stfd)
{
    srs_error_t err = srs_success;

    int fd = srs_netfd_fileno(stfd);
    string ip = srs_get_peer_ip(fd);
    int port = srs_get_peer_port(fd);

    if (ip.empty() && !_srs_config->empty_ip_ok()) {
        srs_warn("empty ip for fd=%d", srs_netfd_fileno(stfd));
    }

    SrsDynamicHttpConn* conn = new SrsDynamicHttpConn(this, stfd, http_mux, ip, port);
    conns.push_back(conn);

    if ((err = conn->start()) != srs_success) {
        return srs_error_wrap(err, "start tcp listener");
    }
    
    return err;
}

void SrsAppCasterFlv::remove(ISrsResource* c)
{
    ISrsConnection* conn = dynamic_cast<ISrsConnection*>(c);
    
    std::vector<ISrsConnection*>::iterator it;
    if ((it = std::find(conns.begin(), conns.end(), conn)) != conns.end()) {
        it = conns.erase(it);
    }
    
    // fixbug: ISrsConnection for CasterFlv is not freed, which could cause memory leak
    // so, free conn which is not managed by SrsServer->conns;
    // @see: https://github.com/ossrs/srs/issues/826
    manager->remove(c);
}

srs_error_t SrsAppCasterFlv::serve_http(ISrsHttpResponseWriter* w, ISrsHttpMessage* r)
{
    SrsHttpMessage* msg = dynamic_cast<SrsHttpMessage*>(r);
    SrsHttpConn* hconn = dynamic_cast<SrsHttpConn*>(msg->connection());
    SrsDynamicHttpConn* dconn = dynamic_cast<SrsDynamicHttpConn*>(hconn->handler());
    srs_assert(dconn);
    
    std::string app = srs_path_dirname(r->path());
    app = srs_string_trim_start(app, "/");
    
    std::string stream = srs_path_basename(r->path());
    stream = srs_string_trim_start(stream, "/");
    
    std::string o = output;
    if (!app.empty() && app != "/") {
        o = srs_string_replace(o, "[app]", app);
    }
    o = srs_string_replace(o, "[stream]", stream);
    
    // remove the extension.
    if (srs_string_ends_with(o, ".flv")) {
        o = o.substr(0, o.length() - 4);
    }
    
    srs_error_t err = dconn->proxy(w, r, o);
    if (err != srs_success) {
        return srs_error_wrap(err, "proxy");
    }
    
    return err;
}

SrsDynamicHttpConn::SrsDynamicHttpConn(ISrsResourceManager* cm, srs_netfd_t fd, SrsHttpServeMux* m, string cip, int cport)
{
    // Create a identify for this client.
    _srs_context->set_id(_srs_context->generate_id());

    manager = cm;
    sdk = NULL;
    pprint = SrsPithyPrint::create_caster();
    skt = new SrsTcpConnection(fd);
    conn = new SrsHttpConn(this, skt, m, cip, cport);
    ip = cip;
    port = cport;

    _srs_config->subscribe(this);
}

SrsDynamicHttpConn::~SrsDynamicHttpConn()
{
    _srs_config->unsubscribe(this);

    srs_freep(conn);
    srs_freep(skt);
    srs_freep(sdk);
    srs_freep(pprint);
}

srs_error_t SrsDynamicHttpConn::proxy(ISrsHttpResponseWriter* w, ISrsHttpMessage* r, std::string o)
{
    srs_error_t err = srs_success;
    
    output = o;
    srs_trace("flv: proxy %s:%d %s to %s", ip.c_str(), port, r->uri().c_str(), output.c_str());

    ISrsHttpResponseReader* rr = r->body_reader();
    SrsHttpFileReader reader(rr);
    SrsFlvDecoder dec;
    
    if ((err = dec.initialize(&reader)) != srs_success) {
        return srs_error_wrap(err, "init decoder");
    }
    
    char header[9];
    if ((err = dec.read_header(header)) != srs_success) {
        return srs_error_wrap(err, "read header");
    }
    
    char pps[4];
    if ((err = dec.read_previous_tag_size(pps)) != srs_success) {
        return srs_error_wrap(err, "read pts");
    }
    
    err = do_proxy(rr, &dec);
    sdk->close();
    
    return err;
}

srs_error_t SrsDynamicHttpConn::do_proxy(ISrsHttpResponseReader* rr, SrsFlvDecoder* dec)
{
    srs_error_t err = srs_success;
    
    srs_freep(sdk);
    
    srs_utime_t cto = SRS_CONSTS_RTMP_TIMEOUT;
    srs_utime_t sto = SRS_CONSTS_RTMP_PULSE;
    sdk = new SrsSimpleRtmpClient(output, cto, sto);
    
    if ((err = sdk->connect()) != srs_success) {
        return srs_error_wrap(err, "connect %s failed, cto=%dms, sto=%dms.", output.c_str(), srsu2msi(cto), srsu2msi(sto));
    }
    
    if ((err = sdk->publish(SRS_CONSTS_RTMP_PROTOCOL_CHUNK_SIZE)) != srs_success) {
        return srs_error_wrap(err, "publish");
    }
    
    char pps[4];
    while (!rr->eof()) {
        pprint->elapse();
        
        char type;
        int32_t size;
        uint32_t time;
        if ((err = dec->read_tag_header(&type, &size, &time)) != srs_success) {
            return srs_error_wrap(err, "read tag header");
        }
        
        char* data = new char[size];
        if ((err = dec->read_tag_data(data, size)) != srs_success) {
            srs_freepa(data);
            return srs_error_wrap(err, "read tag data");
        }
        
        SrsSharedPtrMessage* msg = NULL;
        if ((err = srs_rtmp_create_msg(type, time, data, size, sdk->sid(), &msg)) != srs_success) {
            return srs_error_wrap(err, "create message");
        }
        
        // TODO: FIXME: for post flv, reconnect when error.
        if ((err = sdk->send_and_free_message(msg)) != srs_success) {
            return srs_error_wrap(err, "send message");
        }
        
        if (pprint->can_print()) {
            srs_trace("flv: send msg %d age=%d, dts=%d, size=%d", type, pprint->age(), time, size);
        }
        
        if ((err = dec->read_previous_tag_size(pps)) != srs_success) {
            return srs_error_wrap(err, "read pts");
        }
    }
    
    return err;
}

srs_error_t SrsDynamicHttpConn::on_start()
{
    return srs_success;
}

srs_error_t SrsDynamicHttpConn::on_http_message(ISrsHttpMessage* r, SrsHttpResponseWriter* w)
{
    return srs_success;
}

srs_error_t SrsDynamicHttpConn::on_message_done(ISrsHttpMessage* r, SrsHttpResponseWriter* w)
{
    return srs_success;
}

srs_error_t SrsDynamicHttpConn::on_conn_done(srs_error_t r0)
{
    // Because we use manager to manage this object,
    // not the http connection object, so we must remove it here.
    manager->remove(this);

    return r0;
}

std::string SrsDynamicHttpConn::desc()
{
    return "DHttpConn";
}

std::string SrsDynamicHttpConn::remote_ip()
{
    return conn->remote_ip();
}

const SrsContextId& SrsDynamicHttpConn::get_id()
{
    return conn->get_id();
}

srs_error_t SrsDynamicHttpConn::start()
{
    srs_error_t err = srs_success;

    bool v = _srs_config->get_http_stream_crossdomain();
    if ((err = conn->set_crossdomain_enabled(v)) != srs_success) {
        return srs_error_wrap(err, "set cors=%d", v);
    }

    return conn->start();
}

SrsHttpFileReader::SrsHttpFileReader(ISrsHttpResponseReader* h)
{
    http = h;
}

SrsHttpFileReader::~SrsHttpFileReader()
{
}

srs_error_t SrsHttpFileReader::open(std::string /*file*/)
{
    return srs_success;
}

void SrsHttpFileReader::close()
{
}

bool SrsHttpFileReader::is_open()
{
    return true;
}

int64_t SrsHttpFileReader::tellg()
{
    return 0;
}

void SrsHttpFileReader::skip(int64_t /*size*/)
{
}

int64_t SrsHttpFileReader::seek2(int64_t offset)
{
    return offset;
}

int64_t SrsHttpFileReader::filesize()
{
    return 0;
}

srs_error_t SrsHttpFileReader::read(void* buf, size_t count, ssize_t* pnread)
{
    srs_error_t err = srs_success;
    
    if (http->eof()) {
        return srs_error_new(ERROR_HTTP_REQUEST_EOF, "EOF");
    }
    
    int total_read = 0;
    while (total_read < (int)count) {
        ssize_t nread = 0;
        if ((err = http->read((char*)buf + total_read, (int)(count - total_read), &nread)) != srs_success) {
            return srs_error_wrap(err, "read");
        }
        
        if (nread == 0) {
            err = srs_error_new(ERROR_HTTP_REQUEST_EOF, "EOF");
            break;
        }
        
        srs_assert(nread);
        total_read += (int)nread;
    }
    
    if (pnread) {
        *pnread = total_read;
    }
    
    return err;
}

srs_error_t SrsHttpFileReader::lseek(off_t offset, int whence, off_t* seeked)
{
    // TODO: FIXME: Use HTTP range for seek.
    return srs_success;
}

