/*
* Copyright (C) 2010-2011 Mamadou Diop.
*
* Contact: Mamadou Diop <diopmamadou(at)doubango[dot]org>
*
* This file is part of Open Source Doubango Framework.
*
* DOUBANGO 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 3 of the License, or
* (at your option) any later version.
*
* DOUBANGO 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 DOUBANGO.
*
*/

/**@file tsip_sigcomp.c
 * @brief SigComp helper API.
 *
 * @author Mamadou Diop <diopmamadou(at)doubango[dot]org>
 *

 */
#include "tinysip/sigcomp/tsip_sigcomp.h"

#include "tcomp_manager.h"

#include "tsk_safeobj.h"
#include "tsk_memory.h"
#include "tsk_string.h"
#include "tsk_list.h"
#include "tsk_debug.h"

#include <string.h> /* used by tsk_string.h macros */

/** SigComp compartment */
typedef struct tsip_sigcomp_compartment_s {
    TSK_DECLARE_OBJECT;

    char* id;
    uint64_t stream_id;
    tcomp_result_t *decomp_result;

    /* tinySigComp library is thread-safe but I prefer to add this
    * tcomp_manager_provideCompartmentId() is unsafe */
    TSK_DECLARE_SAFEOBJ;
}
tsip_sigcomp_compartment_t;
const tsk_object_def_t *tsip_sigcomp_compartment_def_t;
typedef tsk_list_t tsip_sigcomp_compartments_L_t;

/** SigComp handler */
typedef struct tsip_sigcomp_s {
    TSK_DECLARE_OBJECT;

    tcomp_manager_handle_t *manager;
    tsip_sigcomp_compartments_L_t* compartments;

    TSK_DECLARE_SAFEOBJ;
}
tsip_sigcomp_t;
const tsk_object_def_t *tsip_sigcomp_def_t;

/*== Predicate function to find a compartment by id */
static int pred_find_compartment_by_id(const tsk_list_item_t *item, const void *id)
{
    if(item && item->data) {
        tsip_sigcomp_compartment_t *compartment = item->data;
        return tsk_strcmp(compartment->id, (const char*)id);
    }
    return -1;
}

/** Creates new SigComp handler
* @param cpb Cycles Per Bit (16, 32, 64 or 128)
* @param dms Decompression Memory Size (should be: 0, 2048, 4096, 8192, 16384, 32768, 65536 or 131072)
* @param sms State Memory Size (should be: 0, 2048, 4096, 8192, 16384, 32768, 65536 or 131072)
* @retval A pointer to a SigComp handler if succeed and Null otherwise.
*/
tsip_sigcomp_handle_t* tsip_sigcomp_handler_create(uint8_t cpb, uint32_t dms, uint32_t sms)
{
    tsip_sigcomp_t* sigcomp = tsk_object_new(tsip_sigcomp_def_t);

    /* create SigComp handler */
    if(!sigcomp) {
        TSK_DEBUG_ERROR("Failed to create new SigComp handler");
        return tsk_null;
    }

    /* create SigComp manager */
    if(!(sigcomp->manager = tcomp_manager_create()) || !(sigcomp->compartments = tsk_list_create())) {
        TSK_DEBUG_ERROR("Failed to create new SigComp manager");
        TSK_OBJECT_SAFE_FREE(sigcomp);
        return tsk_null;
    }

    tcomp_manager_setCycles_Per_Bit(sigcomp->manager, cpb);
    tcomp_manager_setDecompression_Memory_Size(sigcomp->manager, dms);
    tcomp_manager_setState_Memory_Size(sigcomp->manager, sms);

    return sigcomp;
}
/** Creates new SigComp handler
* Adds/Removes dictionaries. These dictionaries will be used both for compression and decompression.
* And this will apply to all compartments holded by the handler.
* @param self The SigComp manager holding the dictionaries to add/remove.
* @param sip_n_sdp Whether to add the SIP/SDP dictionary (RFC 3485). If @a tsk_false_t this dictionary will be added,
* otherwise it will be removed.
* @param pres Whether to add the Presence dictionary (RFC 5112). If @a tsk_false_t this dictionary will be added,
* otherwise it will be removed.
*/
int tsip_sigcomp_handler_set_dicts(tsip_sigcomp_handle_t* self, tsk_bool_t sip_n_sdp, tsk_bool_t pres)
{
    tsip_sigcomp_t* sigcomp = self;

    if(!sigcomp || !sigcomp->manager) {
        TSK_DEBUG_ERROR("Invalid parameter");
        return -1;
    }

    tsk_safeobj_lock(sigcomp);

    /* SIP/SDP (RFC 3485) */
    if(sip_n_sdp) {
        tcomp_manager_addSipSdpDictionary(sigcomp->manager);
    }
    else {
        // FIXME: To be implemented in tinySigComp
        /* tcomp_manager_removeSipSdpDictionary(sigcomp->manager); */
    }

    /* SIP/SDP (RFC 5112) */
    if(pres) {
        tcomp_manager_addPresenceDictionary(sigcomp->manager);
    }
    else {
        // FIXME: To be implemented in tinySigComp
        /* tcomp_manager_removePresenceDictionary(sigcomp->manager); */
    }

    tsk_safeobj_unlock(sigcomp);

    return 0;
}

/** Adds new SigComp compartement to the handler
* @param self The SigComp handler
* @param comp_id The id of the new compartment to add
* @retval Zero if succeed and non-zero error code otherwise.
*/
int tsip_sigcomp_handler_add_compartment(tsip_sigcomp_handle_t* self, const char* comp_id)
{
    tsip_sigcomp_compartment_t* compartment;
    tsip_sigcomp_t* sigcomp = self;
    int ret = -1;

    if(!sigcomp || !comp_id) {
        TSK_DEBUG_ERROR("Invalid parameter");
        return -1;
    }

    tsk_safeobj_lock(sigcomp);

    /* check if we already have a compartment with the same id */
    if(tsk_list_find_object_by_pred(sigcomp->compartments, pred_find_compartment_by_id, comp_id)) {
        TSK_DEBUG_ERROR("Failed to add new SigComp compartment. %s already exist.", comp_id);
        ret = -2;
        goto bail;
    }

    if((compartment = tsk_object_new(tsip_sigcomp_compartment_def_t))) {
        compartment->id = tsk_strdup(comp_id);
        tcomp_result_setCompartmentId(compartment->decomp_result, compartment->id, tsk_strlen(compartment->id));

        tsk_list_push_back_data(sigcomp->compartments, (void**)&compartment);
        ret = 0;
        goto bail;
    }
    else {
        TSK_DEBUG_ERROR("Failed to create new SigComp compartment");
        ret = -3;
        goto bail;
    }

bail:
    tsk_safeobj_unlock(sigcomp);

    return ret;
}

/** Removes a SigComp compartement from the handler
* @param self The SigComp handler
* @param comp_id The id of the new compartment to remove
* @retval Zero if succeed and non-zero error code otherwise.
*/
int tsip_sigcomp_handler_remove_compartment(tsip_sigcomp_handle_t* self, const char* comp_id)
{
    tsip_sigcomp_t* sigcomp = self;

    if(!sigcomp || !comp_id) {
        TSK_DEBUG_ERROR("Invalid parameter");
        return -1;
    }

    tsk_safeobj_lock(sigcomp);
    tsk_list_remove_item_by_pred(sigcomp->compartments, pred_find_compartment_by_id, comp_id);
    tsk_safeobj_unlock(sigcomp);

    return 0;
}

// FIXME
const char* tsip_sigcomp_handler_fixme_getcompid(const tsip_sigcomp_handle_t* self)
{
    const tsip_sigcomp_t* sigcomp = self;
    const char* comp_id = tsk_null;

    if(!sigcomp) {
        TSK_DEBUG_ERROR("Invalid parameter");
        return tsk_null;
    }

    tsk_safeobj_lock(sigcomp);
    if(!TSK_LIST_IS_EMPTY(sigcomp->compartments)) {
        comp_id = ((tsip_sigcomp_compartment_t*)TSK_LIST_FIRST_DATA(sigcomp->compartments))->id;
    }
    tsk_safeobj_unlock(sigcomp);
    return comp_id;
}

/** Close all SigComp compartments
* @param self The SigComp handler
*/
int tsip_sigcomp_close_all(tsip_sigcomp_handle_t* self)
{
    tsip_sigcomp_t* sigcomp = self;
    const tsk_list_item_t* item;
    const char* comp_id;

    if(!sigcomp) {
        return -1;
    }

    tsk_safeobj_lock(sigcomp);

    tsk_list_foreach(item, sigcomp->compartments) {
        comp_id = ((tsip_sigcomp_compartment_t*)item->data)->id;
        tcomp_manager_closeCompartment(sigcomp->manager, comp_id, tsk_strlen(comp_id));
    }

    tsk_safeobj_unlock(sigcomp);

    return 0;
}

/** Compress a Sip message
* @param self The SigComp handler
* @param comp_id The id of the compartement to use for compression. This compartment should be previously added using
* @ref tsip_sigcomp_handler_add_compartment()
* @param is_stream Indicates whether we are about to compress a stream message or not
* @param in_data Sip input data to compress
* @param in_size The size of the Sip input data
* @param out_data A pointer to the output data where the compressed message will be copied. It's up to you to allocate
* this buffer before calling this function.
* @param out_maxsize The maximum size of the @a out_data. Used as guard to avoid buffer overflow.
* @retval Size of the compressed data.
*/
tsk_size_t tsip_sigcomp_handler_compress(tsip_sigcomp_handle_t* self, const char* comp_id, tsk_bool_t is_stream, const void* in_data, tsk_size_t in_size, void* out_data, tsk_size_t out_maxsize)
{
    tsk_size_t out_size = 0;
    tsip_sigcomp_compartment_t* compartment;
    tsip_sigcomp_t* sigcomp = self;

    if(!sigcomp || !in_data || !in_size || !out_data || !out_maxsize) {
        TSK_DEBUG_ERROR("Invalid parameter");
        return 0;
    }

    /* find the compartment */
    if(!(compartment = (tsip_sigcomp_compartment_t*)tsk_list_find_object_by_pred(sigcomp->compartments, pred_find_compartment_by_id, comp_id))) {
        TSK_DEBUG_ERROR("%s not a valid compartment Id", comp_id);
        return 0;
    }

    /* take ownership and lock() */
    compartment = tsk_object_ref(compartment); /* take ownership instead of locking the handler(which will lock all compartments) */
    tsk_safeobj_lock(compartment);

    /* compress the message */
    out_size = tcomp_manager_compress(sigcomp->manager, compartment->id, tsk_strlen(compartment->id), in_data, in_size, out_data, out_maxsize, is_stream);

    /* release ownership and unlock() */
    tsk_safeobj_unlock(compartment);
    tsk_object_unref(compartment);

    return out_size;
}

/** UnCompress a SigComp message
* @param self The SigComp handler
* @param comp_id The compartment id to use after successful decompression.
* @param is_stream Indicates whether we are about to uncompress a stream message or not
* @param in_data A pointer to the SigComp buffer to decompress
* @param in_size The size of the SigComp buffer
* @param out_data A pointer to the output data where the uncompressed message will be copied. It's up to you to allocate
* this buffer before calling this function.
* @param out_maxsize The maximum size of the @a out_data. Used as guard to avoid buffer overflow.
* @param is_nack Used to signal whether the uncompressed (result) message is a NACK or a Sip Message.
* @retval Size of the uncompressed data.
*/
tsk_size_t tsip_sigcomp_handler_uncompress(tsip_sigcomp_handle_t* self, const char* comp_id, tsk_bool_t is_stream, const void* in_data, tsk_size_t in_size, void* out_data, tsk_size_t out_maxsize, tsk_bool_t* is_nack)
{
    tsk_size_t out_size = 0;
    tsip_sigcomp_compartment_t* compartment;
    tsip_sigcomp_t* sigcomp = self;

    if(!sigcomp || !in_data || !in_size || !out_data || !out_maxsize || !is_nack) {
        TSK_DEBUG_ERROR("Invalid parameter");
        return 0;
    }

    /* find the compartment */
    if(!(compartment = (tsip_sigcomp_compartment_t*)tsk_list_find_object_by_pred(sigcomp->compartments, pred_find_compartment_by_id, comp_id))) {
        TSK_DEBUG_ERROR("%s not a valid compartment Id", comp_id);
        return 0;
    }

    *is_nack = tsk_false;

    /* take ownership and lock() */
    compartment = tsk_object_ref(compartment); /* take ownership instead of locking the handler(which will lock all compartments) */
    tsk_safeobj_lock(compartment);

    /* uncompress the message */
    tcomp_result_setOutputBuffer(compartment->decomp_result, out_data, out_maxsize, is_stream, compartment->stream_id); // set the output buffer where to copy uncompressed message
    out_size = tcomp_manager_decompress(sigcomp->manager, in_data, in_size, compartment->decomp_result);
    if(out_size) {
        // provide the compartment id --> save temp states
        tcomp_manager_provideCompartmentId(sigcomp->manager, compartment->decomp_result);
    }
    else {
        if((*is_nack = compartment->decomp_result->isNack)) {
            tsk_size_t nack_info_size;
            if(compartment->decomp_result->nack_info && (nack_info_size = tcomp_buffer_getSize(compartment->decomp_result->nack_info))) {
                out_size = (nack_info_size > out_maxsize) ? out_maxsize : nack_info_size;
                memcpy(out_data, tcomp_buffer_getBuffer(compartment->decomp_result->nack_info), out_size);
                TSK_DEBUG_INFO("We got a NACK to send()");
            }
            else {
                TSK_DEBUG_INFO("We got a NACK from the remote party");
            }
        }
        else {
            /* Should never happen */
            TSK_DEBUG_ERROR("SigComp decompression failed");
        }
    }

    /* release ownership and unlock() */
    tsk_safeobj_unlock(compartment);
    tsk_object_unref(compartment);

    return out_size;
}

/** Try to unCompress the next stream chunck. Must only be used with stream compartments.
* When you are dealing with stream stream transports, then you should call this function several times until
* it returns zero.
* @param self The SigComp handler
* @param comp_id The compartment id to use after successful decompression
* @param nack_data Pointer to the NACL message. We be filled only if @a is_nack is equal to @a tsk_true
* @param is_nack Used to signal whether the uncompressed (result) message is a NACK or a Sip Message.
* @retval Size of the uncompressed data plus size of all previously uncompressed chuncks except NACKs.
* If the uncompressed message is a NACK, then the returned size will be equal to the length of the NACK
* to send to the remote party.
*/
tsk_size_t tsip_sigcomp_handler_uncompress_next(tsip_sigcomp_handle_t* self, const char* comp_id, void** nack_data, tsk_bool_t* is_nack)
{
    tsk_size_t out_size = 0;
    tsip_sigcomp_compartment_t* compartment;
    tsip_sigcomp_t* sigcomp = self;

    if(!sigcomp || !is_nack || !nack_data) {
        TSK_DEBUG_ERROR("Invalid parameter");
        return 0;
    }

    /* find the compartment */
    if(!(compartment = (tsip_sigcomp_compartment_t*)tsk_list_find_object_by_pred(sigcomp->compartments, pred_find_compartment_by_id, comp_id))) {
        TSK_DEBUG_ERROR("%s not a valid compartment Id", comp_id);
        return 0;
    }

    /* take ownership and lock() */
    compartment = tsk_object_ref(compartment); /* take ownership instead of locking the handler(which will lock all compartments) */
    tsk_safeobj_lock(compartment);

    /* uncompress the next chunk
    * the returned size the the total size which includes previous chuncks uncompressed
    * using tsip_sigcomp_handler_uncompress()
    */
    out_size = tcomp_manager_getNextStreamMessage(sigcomp->manager, compartment->decomp_result);

    if(out_size) {
        // provide the compartment id --> save temp states
        tcomp_manager_provideCompartmentId(sigcomp->manager, compartment->decomp_result);
    }
    else {
        if((*is_nack = compartment->decomp_result->isNack)) {
            tsk_size_t nack_info_size;
            if(compartment->decomp_result->nack_info && (nack_info_size = tcomp_buffer_getSize(compartment->decomp_result->nack_info))) {
                if((*nack_data = tsk_calloc(nack_info_size, sizeof(uint8_t)))) {
                    memcpy(*nack_data, tcomp_buffer_getBuffer(compartment->decomp_result->nack_info), nack_info_size);
                }
                TSK_DEBUG_INFO("We got a NACK to send()");
            }
            else {
                TSK_DEBUG_INFO("We got a NACK from the remote party");
            }
        }
    }

    /* release ownership and unlock() */
    tsk_safeobj_unlock(compartment);
    tsk_object_unref(compartment);

    return out_size;
}

//===========================================================================
//	SIP SigComp Handler object definition
//
static tsk_object_t* tsip_sigcomp_ctor(tsk_object_t * self, va_list * app)
{
    tsip_sigcomp_t *sigcomp = self;
    if(sigcomp) {
        /* Done by tsip_sigcomp_create()
        sigcomp->manager = tcomp_manager_create();
        sigcomp->compartments = tsk_list_create();
        */

        tsk_safeobj_init(sigcomp);
    }
    return self;
}

static tsk_object_t* tsip_sigcomp_dtor(tsk_object_t * self)
{
    tsip_sigcomp_t *sigcomp = self;
    if(sigcomp) {
        TSK_OBJECT_SAFE_FREE(sigcomp->manager);
        TSK_OBJECT_SAFE_FREE(sigcomp->compartments);

        tsk_safeobj_deinit(sigcomp);
    }

    return self;
}

static const tsk_object_def_t tsip_sigcomp_def_s = {
    sizeof(tsip_sigcomp_t),
    tsip_sigcomp_ctor,
    tsip_sigcomp_dtor,
    tsk_null,
};
const tsk_object_def_t *tsip_sigcomp_def_t = &tsip_sigcomp_def_s;


//===========================================================================
//	SIP SigComp Compartment object definition
//
static tsk_object_t* tsip_sigcomp_compartment_ctor(tsk_object_t * self, va_list * app)
{
    static uint64_t __unique_stream_id = 0;

    tsip_sigcomp_compartment_t *compartment = self;
    if(compartment) {
        compartment->decomp_result = tcomp_result_create();
        compartment->stream_id = ++(__unique_stream_id);
        tsk_safeobj_init(compartment);
    }
    return self;
}

static tsk_object_t* tsip_sigcomp_compartment_dtor(tsk_object_t * self)
{
    tsip_sigcomp_compartment_t *compartment = self;
    if(compartment) {
        TSK_FREE(compartment->id);
        TSK_OBJECT_SAFE_FREE(compartment->decomp_result);

        tsk_safeobj_deinit(compartment);
    }

    return self;
}
int	tsip_sigcomp_compartment_cmp(const tsk_object_t * _c1, const tsk_object_t * _c2)
{
    const tsip_sigcomp_compartment_t *c1 = _c1;
    const tsip_sigcomp_compartment_t *c2 = _c2;

    if(c1 && c2) {
        return tsk_strcmp(c1->id, c2->id);
    }
    else {
        return (c1 - c2);
    }
}

static const tsk_object_def_t tsip_sigcomp_compartment_def_s = {
    sizeof(tsip_sigcomp_compartment_t),
    tsip_sigcomp_compartment_ctor,
    tsip_sigcomp_compartment_dtor,
    tsip_sigcomp_compartment_cmp,
};
const tsk_object_def_t *tsip_sigcomp_compartment_def_t = &tsip_sigcomp_compartment_def_s;