/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "cpr_types.h"
#include "cpr_stdlib.h"
#include "cpr_stdio.h"
#include "cpr_string.h"
#include "cpr_errno.h"
#include "phone.h"
#include "phntask.h"
#include "lsm.h"
#include "ccapi.h"
#include "phone_debug.h"
#include "fim.h"
#include "sdp.h"
#include "debug.h"
#include "gsm_sdp.h"
#include "uiapi.h"
#include "gsm.h"
#include "prot_configmgr.h"
#include "singly_link_list.h"

typedef enum dcsm_state {
    DCSM_S_MIN = -1,
    DCSM_S_READY,
    DCSM_S_WAITING,
    DCSM_S_MAX
} dcsm_state_e;

#define DCSM_MAX_CALL_IDS     (LSM_MAX_CALLS)

static struct dcsm_icb_t {
    callid_t            call_ids[DCSM_MAX_CALL_IDS];
    line_t              line;
    int                 gsm_state;
    sll_handle_t        s_msg_list;

    dcsm_state_e        state;
} dcsm_cb;

static const char *dcsm_state_names[] = {
    "DCSM_READY",
    "DCSM_WAITING"
};

extern cc_int32_t g_dcsmDebug;

static sm_rcs_t dcsm_wait_ev_feature_handling(void *event, int event_id);
static sm_rcs_t dcsm_wait_ev_offhook_handling(void *event, int event_id);
static sm_rcs_t dcsm_wait_ev_dialstring_handling(void *event, int event_id);

typedef sm_rcs_t (*pdcsm_sm_evt_handler)(void *event, int event_id);

typedef struct _dcsm_table_t {
    int min_state;
    int max_state;
    int min_event;
    int max_event;
    pdcsm_sm_evt_handler *table;
} dcsm_table_t;


static pdcsm_sm_evt_handler dcsm_function_table[DCSM_S_MAX][CC_MSG_MAX] =
{
/* DCSM_S_READY ------------------------------------------------------------ */
    {
    /* DCSM_E_SETUP            */ NULL,
    /* DCSM_E_SETUP_ACK        */ NULL,
    /* DCSM_E_PROCEEDING       */ NULL,
    /* DCSM_E_ALERTING         */ NULL,
    /* DCSM_E_CONNECTED        */ NULL,
    /* DCSM_E_CONNECTED_ACK    */ NULL,
    /* DCSM_E_RELEASE          */ NULL,
    /* DCSM_E_RELEASE_COMPLETE */ NULL,
    /* DCSM_E_FEATURE          */ NULL,
    /* DCSM_E_FEATURE_ACK      */ NULL,
    /* DCSM_E_OFFHOOK          */ NULL,
    /* DCSM_E_ONHOOK           */ NULL,
    /* DCSM_E_LINE             */ NULL,
    /* DCSM_E_DIGIT_BEGIN      */ NULL,
    /* DCSM_E_DIGIT_END        */ NULL,
    /* DCSM_E_DIALSTRING       */ NULL,
    /* DCSM_E_MWI              */ NULL,
    /* DCSM_E_SESSION_AUDIT    */ NULL
    },

/* DCSM_S_WAITING----------------------------------------------------- */
    {
    /* DCSM_E_SETUP            */ NULL,
    /* DCSM_E_SETUP_ACK        */ NULL,
    /* DCSM_E_PROCEEDING       */ NULL,
    /* DCSM_E_ALERTING         */ NULL,
    /* DCSM_E_CONNECTED        */ NULL,
    /* DCSM_E_CONNECTED_ACK    */ NULL,
    /* DCSM_E_RELEASE          */ NULL,
    /* DCSM_E_RELEASE_COMPLETE */ NULL,
    /* DCSM_E_FEATURE          */ dcsm_wait_ev_feature_handling,
    /* DCSM_E_FEATURE_ACK      */ NULL,
    /* DCSM_E_OFFHOOK          */ dcsm_wait_ev_offhook_handling,
    /* DCSM_E_ONHOOK           */ NULL,
    /* DCSM_E_LINE             */ NULL,
    /* DCSM_E_DIGIT_BEGIN      */ NULL,
    /* DCSM_E_DIGIT_END        */ NULL,
    /* DCSM_E_DIALSTRING       */ dcsm_wait_ev_dialstring_handling,
    /* DCSM_E_MWI              */ NULL,
    /* DCSM_E_SESSION_AUDIT    */ NULL
    },
};

static dcsm_table_t dcsm_sm_table;
static dcsm_table_t *pdcsm_sm_table = &dcsm_sm_table;

/*
 * Adds event to the dcsm queue.
 *
 *  @param event - Call control event to add
 *
 *  @return TRUE if the event is added.

 *
 */
static boolean
dcsm_add_event_to_queue (void *event)
{
    (void) sll_append(dcsm_cb.s_msg_list, event);

    return TRUE;
}

/*
 * Get a event from the queue.
 *
 *  @param none
 *
 *  @return pointer to the event.

 *
 */
static void *
dcsm_get_first_event_from_queue (void)
{
    void *msg_ptr = NULL;

    msg_ptr = sll_next(dcsm_cb.s_msg_list, NULL);

    sll_remove(dcsm_cb.s_msg_list, msg_ptr);

    return(msg_ptr);
}

/*
 * Get dcsm state name.
 *
 *  @param int - state id
 *
 *  @return ponter to the state name either
 *  DCSM_READY or DCSM_WAITING.
 *
 */
const char *dcsm_get_state_name (int state)
{
    if ((state <= DCSM_S_MIN) ||
            (state >= DCSM_S_MAX)) {
        return (get_debug_string(GSM_UNDEFINED));
    }

    return dcsm_state_names[state];
}

/**
 * Feed the event to FIM state machine a direct function call
 *  to process message retrieved from the queue.
 *
 * @param void * - pointer to the message to be processed
 *
 * @return none.
 */
static void dcsm_process_event_to_gsm (void *msg_ptr)
{
    if (fim_process_event(msg_ptr, FALSE) == TRUE) {

        fim_free_event(msg_ptr);

        /* Release buffer too */
        cpr_free(msg_ptr);
    }
}


/**
 * Process ready state events.
 *
 * @param none
 *
 * @return none.
 */

static void dcsm_do_ready_state_job (void)
{
    static const char fname[] = "dcsm_do_ready_state_job";
    void            *msg_ptr;
    int             event_id;
    cc_feature_t    *feat_msg = NULL;
    callid_t        call_id = CC_NO_CALL_ID;

    if (dcsm_cb.state != DCSM_S_READY) {
        DEF_DEBUG(DEB_F_PREFIX": not in ready state.\n",
            DEB_F_PREFIX_ARGS("DCSM", fname));
        return;
    }

    msg_ptr = dcsm_get_first_event_from_queue();

    /* Check if there is any msg available */
    if (msg_ptr != NULL) {
        event_id = (int)(((cc_setup_t *)msg_ptr)->msg_id);
        if (event_id == CC_MSG_FEATURE) {
            feat_msg = (cc_feature_t *) msg_ptr;
            if (feat_msg != NULL) {
                call_id = feat_msg->call_id;
            }
        }

        DEF_DEBUG(DEB_F_PREFIX"%d: event (%s%s)\n",
            DEB_F_PREFIX_ARGS("DCSM", fname), call_id,
                     cc_msg_name((cc_msgs_t)(event_id)),
                     feat_msg ? cc_feature_name(feat_msg->feature_id):" ");
        dcsm_process_event_to_gsm(msg_ptr);
    }
}

/**
 * Function process events based on the state of DCSM.
 *
 * @param none
 *
 * @return none.
 */
void dcsm_process_jobs (void)
{
    dcsm_do_ready_state_job();
}

/**
 * Adds call_id to the list of call_id's which made DCSM to move
 *  to waiting state.
 *
 * @param callid_t - call id that has to be added to the list
 *
 * @return none.
 */
static void dcsm_add_call_id_to_list (callid_t call_id)
{
    static const char fname[] = "dcsm_add_call_id_to_list";
    int i, loc = -1;

    for (i=0; i< DCSM_MAX_CALL_IDS; i++) {
        if (dcsm_cb.call_ids[i] == CC_NO_CALL_ID) {
            loc = i;
        } else if (dcsm_cb.call_ids[i] == call_id) {
            //Call_id already present so do not try to add again
            return;
        }
    }

    if (loc == -1) {

        /* Should never happen as there is a space to store call_id
         * for each calls
        */
        DCSM_ERROR(DCSM_F_PREFIX"DCSM No space to store call_id.\n",
                                    DEB_F_PREFIX_ARGS("DCSM", fname));
        return;
    }

    dcsm_cb.call_ids[loc] = call_id;
}

/**
 * Remove call_id from the list and see if the call_ids list is null.
 *
 * @param callid_t - call id that to be removed from the list.
 *
 * @return TRUE - if the call_ids list is empty.
 *          FALSE - call_ids list is not empty.
 */
static boolean dcsm_remove_check_for_empty_list (callid_t call_id)
{
    int         i;
    boolean      call_id_present = FALSE;

    for (i=0; i< DCSM_MAX_CALL_IDS; i++) {
        if (dcsm_cb.call_ids[i] == call_id) {
            dcsm_cb.call_ids[i] = CC_NO_CALL_ID;

            /* Found out that other call_id exist by setting
             * call_id_preset, so return true, don't have to
             * continue
             */
            if (call_id_present == TRUE) {
                return FALSE;
            }

        } else if (dcsm_cb.call_ids[i] != CC_NO_CALL_ID) {
            call_id_present = TRUE;
        }
    }

    if (call_id_present == TRUE) {
        return(FALSE);
    }

    return(TRUE);
}


/*
 *      The function responsible for setting gsm state machine.
 *
 *  @param callid_t - call id of the call
 *         state - current GSM state
 *
 *  @return void
 *
 */
void
dcsm_update_gsm_state (fsm_fcb_t *fcb, callid_t call_id, int state)
{
    int    last_state;
    static const char fname[] = "dcsm_update_gsm_state";
    fsmdef_dcb_t *dcb;

    if (fcb->fsm_type != FSM_TYPE_DEF) {
        DEF_DEBUG(DEB_F_PREFIX"%d: Not handling for %s\n",
                  DEB_F_PREFIX_ARGS("DCSM", fname), call_id,
                  fsm_type_name(fcb->fsm_type));
        return;
    }

    last_state = dcsm_cb.state;

    switch (state) {
        case FSMDEF_S_RELEASING:
            dcb = fsmdef_get_dcb_by_call_id(call_id);
            if (dcb && dcb->send_release == FALSE) {
                /* This call is already released from SIP persepctive. so no need to wait */
                break;
            }
        case FSMDEF_S_CONNECTING:
        case FSMDEF_S_HOLD_PENDING:
        case FSMDEF_S_RESUME_PENDING:
            dcsm_add_call_id_to_list(call_id);

            dcsm_cb.state = DCSM_S_WAITING;
            break;
        case FSMDEF_S_MIN:
        case FSMDEF_S_IDLE:
        case FSMDEF_S_COLLECT_INFO:
        case FSMDEF_S_CALL_SENT:
        case FSMDEF_S_OUTGOING_PROCEEDING:
        case FSMDEF_S_KPML_COLLECT_INFO:
        case FSMDEF_S_OUTGOING_ALERTING:
        case FSMDEF_S_INCOMING_ALERTING:
        case FSMDEF_S_JOINING:
        case FSMDEF_S_CONNECTED:
        case FSMDEF_S_CONNECTED_MEDIA_PEND:
        case FSMDEF_S_HOLDING:
        case FSMDEF_S_PRESERVED:
        case FSMDEF_S_MAX:
            /* If there are no other call_id then move it to
             * ready state else, it will remain in waiting
             * state
             */
            if (dcsm_remove_check_for_empty_list(call_id) == TRUE) {
                dcsm_cb.state = DCSM_S_READY;
                /* Check if there are any pending events in the queue
                 * if so send a DCSM_EV_READY to the GSM so dcsm will
                 * get a chance to execute.
                 */
                if (sll_count(dcsm_cb.s_msg_list) > 0 ) {
                    if (gsm_send_msg(DCSM_EV_READY, NULL, 0) == CPR_FAILURE) {
                        DCSM_ERROR(DCSM_F_PREFIX"send DCSM_EV_READY ERROR.\n",
                                        DEB_F_PREFIX_ARGS(DCSM, fname));
                    }
                }
            }

            break;
        default:
            break;
    }

    DEF_DEBUG(DEB_F_PREFIX"%d : %s --> %s\n",
            DEB_F_PREFIX_ARGS("DCSM", fname), call_id,
            dcsm_get_state_name(last_state),
            dcsm_get_state_name(dcsm_cb.state));
    return;
}

/**
 *
 * Feature passed through when state machine is in waiting state
 *
 * @param sm_event_t
 *
 * @return  sm_rcs_t
 *
 * @pre     (none)
 */
static sm_rcs_t
dcsm_wait_ev_offhook_handling (void *event, int event_id)
{
    static const char fname[] = "dcsm_wait_ev_offhook_handling";

    DEF_DEBUG(DEB_F_PREFIX": offhook\n",
                     DEB_F_PREFIX_ARGS("DCSM", fname));

    dcsm_add_event_to_queue(event);
    return (SM_RC_END);
}
/**
 *
 * Feature passed through when state machine is in waiting state
 *
 * @param sm_event_t
 *
 * @return  sm_rcs_t
 *
 * @pre     (none)
 */
static sm_rcs_t
dcsm_wait_ev_feature_handling (void *event, int event_id)
{
    static const char fname[] = "dcsm_wait_ev_feature_handling";
    cc_feature_t     *feat_msg     = (cc_feature_t *) event;
    sm_rcs_t   rc = SM_RC_END;
    cc_features_t      ftr_id = CC_FEATURE_UNDEFINED;
    callid_t           call_id = CC_NO_CALL_ID;

    if (feat_msg != NULL) {
        ftr_id  = feat_msg->feature_id;
        call_id = feat_msg->call_id;
    }

    DEF_DEBUG(DEB_F_PREFIX"%d: id= %s%s\n",
                     DEB_F_PREFIX_ARGS("DCSM", fname), call_id,
                    cc_msg_name((cc_msgs_t)(event_id)),
                     feat_msg ? cc_feature_name(feat_msg->feature_id):" ");

    switch (ftr_id) {
        case CC_FEATURE_ANSWER:
        case CC_FEATURE_NEW_CALL:
        case CC_FEATURE_REDIAL:
        case CC_FEATURE_RESUME:
        case CC_FEATURE_JOIN:
            dcsm_add_event_to_queue(event);
            DEF_DEBUG(DEB_F_PREFIX"%d: Event queued\n",
                     DEB_F_PREFIX_ARGS("DCSM", fname), call_id);
            rc = SM_RC_END;
            break;
        default:
            DEF_DEBUG(DEB_F_PREFIX"%d: Feature msg not handled\n",
                     DEB_F_PREFIX_ARGS("DCSM", fname), call_id);

            rc = SM_RC_CONT;
            break;
    }


    return (rc);

}

/**
 *
 * Feature passed through when state machine is in waiting state
 *
 * @param sm_event_t
 *
 * @return  sm_rcs_t
 *
 * @pre     (none)
 */
static sm_rcs_t
dcsm_wait_ev_dialstring_handling (void *event, int event_id)
{
    static const char fname[] = "dcsm_wait_ev_dialstring_handling";

    DEF_DEBUG(DEB_F_PREFIX": dialstring\n",
                     DEB_F_PREFIX_ARGS("DCSM", fname));

    dcsm_add_event_to_queue(event);
    return (SM_RC_END);
}

/**
 *
 * Feature passed through when state machine is in waiting state
 *
 * @param sm_event_t
 *
 * @return  sm_rcs_t
 *
 * @pre     (none)
 */
sm_rcs_t
dcsm_process_event (void *event, int event_id)
{
    static const char fname[] = "dcsm_process_event";
    callid_t   call_id;
    int        state_id;
    sm_rcs_t   rc       = SM_RC_CONT;
    fsm_fcb_t *fcb      = (fsm_fcb_t *) event;
    cc_feature_t  *feat_msg = NULL;
    pdcsm_sm_evt_handler hdlr; /* cached handler in order to compute its addr once */

    call_id  = fcb->call_id;

    if (event_id == CC_MSG_FEATURE) {
        feat_msg = (cc_feature_t *) event;

        if (feat_msg != NULL){
            call_id = feat_msg->call_id;
        }
    }

    DEF_DEBUG(DEB_F_PREFIX"DCSM %-4d:(%s:%s%s)\n",
                     DEB_F_PREFIX_ARGS("DCSM", fname), call_id,
                     dcsm_get_state_name(dcsm_cb.state),
                     cc_msg_name((cc_msgs_t)(event_id)),
                     feat_msg ? cc_feature_name(feat_msg->feature_id):" ");

    state_id = dcsm_cb.state; // Get current state;

   /*
     * validate the state and event
     * and that there is a valid function for this state-event pair.
     */
    if ((state_id > pdcsm_sm_table->min_state) &&
        (state_id < pdcsm_sm_table->max_state) &&
        (event_id > pdcsm_sm_table->min_event) &&
        (event_id < pdcsm_sm_table->max_event)) {

        if ((hdlr = pdcsm_sm_table->table[pdcsm_sm_table->max_event * state_id +
                            event_id]) != NULL) {
            DEF_DEBUG(DEB_F_PREFIX"%-4d: dcsm entry: (%s)\n",
                         DEB_F_PREFIX_ARGS("DCSM", fname), call_id,
                     cc_msg_name((cc_msgs_t)(event_id)));

            rc = hdlr(event, event_id);
        }

    }

    return (rc);

}

/*
 *      Function responsible for searching the list.
 *
 *  @param cac_data_t *key_p - pointer to the key.
 *  @param cac_data_t *cac_data - cac data.
 *
 *  @return void
 *
 */
static sll_match_e
dcsm_match_event (void *key_p, void *msg_data)
{
    return SLL_MATCH_FOUND;
}

/**
 *
 * Show function for DCSM
 *
 * @param argc - number of parameter passed
 *        argv - argument passed
 *
 * @return     0 - if function successful
 */
cc_int32_t
dcsm_show_cmd (cc_int32_t argc, const char *argv[])
{
    void *msg_ptr;
    int i;
    cc_setup_t     *msg;
    cc_msgs_t       msg_id;
    line_t    line;
    callid_t  call_id;
    cc_feature_t  *feat_msg = NULL;


    /*
     * check if need help
     */
    if ((argc == 2) && (argv[1][0] == '?')) {
        debugif_printf("%s", "show dcsm\n");
        return (0);
    }


    if (dcsm_cb.s_msg_list == NULL) {
        return(0);
    }

    debugif_printf("%s", "\n-------------------------- DCSM Data --------------------------");
    debugif_printf("\nDCSM State = %s",dcsm_get_state_name(dcsm_cb.state));
    debugif_printf("%s", "\nDCSM waiting calls \n");

    for (i=0; i< DCSM_MAX_CALL_IDS; i++) {
        if (dcsm_cb.call_ids[i] != CC_NO_CALL_ID) {
            debugif_printf("%d ", dcsm_cb.call_ids[i]);
        }
    }
    debugif_printf("%s", "\n");

    debugif_printf("%s", "\nDCSM waiting events \n");
    i = 0;
    msg_ptr = sll_next(dcsm_cb.s_msg_list, NULL);
    while (msg_ptr) {
        msg_ptr = sll_next(dcsm_cb.s_msg_list, msg_ptr);

        if (msg_ptr) {
            msg = (cc_setup_t *) msg_ptr;
            msg_id   = msg->msg_id;
            call_id  = msg->call_id;
            line     = msg->line;
            if ((int)msg_id == CC_MSG_FEATURE) {
                feat_msg = (cc_feature_t *) msg_ptr;
            }

            debugif_printf("Event %d (%d/%d): (%s%s)\n",
                       i++, line, call_id, cc_msg_name(msg_id),
                        feat_msg ? cc_feature_name(feat_msg->feature_id):" ");
        }
    }
    debugif_printf("%s", "\n-------------------------- DCSM Data Done-----------------------");

    return (0);
}


/**
 *
 * Initialize dcsm state machine.
 *
 * @param none
 *
 * @return  none
 *
 * @pre     none
 */
void
dcsm_init (void)
{
    static const char fname[] = "dcsm_init";
    int i;

    /*
     * Initialize the state/event table.
     */
    dcsm_sm_table.min_state = DCSM_S_MIN;
    dcsm_sm_table.max_state = DCSM_S_MAX;
    dcsm_sm_table.min_event = CC_MSG_MIN;
    dcsm_sm_table.max_event = CC_MSG_MAX;
    dcsm_sm_table.table     = (&(dcsm_function_table[0][0]));

    dcsm_cb.state = DCSM_S_READY;

    for (i=0; i< DCSM_MAX_CALL_IDS; i++) {
        dcsm_cb.call_ids[i] = CC_NO_CALL_ID;
    }

    /* allocate and initialize cac list */
    dcsm_cb.s_msg_list = sll_create((sll_match_e(*)(void *, void *))
                            dcsm_match_event);

    if (dcsm_cb.s_msg_list == NULL) {
        DCSM_ERROR(DCSM_F_PREFIX"DCSM CB creation failed.\n",
                                    DEB_F_PREFIX_ARGS("DCSM", fname));

    }

}

/**
 *
 * Shut down routine for dcsm state machine.
 *
 * @param none
 *
 * @return  none
 *
 * @pre     none
 */
void
dcsm_shutdown (void)
{
    void *msg_ptr;

    if (dcsm_cb.s_msg_list == NULL) {
        return;
    }

    msg_ptr = sll_next(dcsm_cb.s_msg_list, NULL);
    while (msg_ptr) {
        msg_ptr = sll_next(dcsm_cb.s_msg_list, msg_ptr);

        if (msg_ptr) {
            fim_free_event(msg_ptr);

            /* Release buffer too */
            cpr_free(msg_ptr);
        }
    }

    sll_destroy(dcsm_cb.s_msg_list);
    dcsm_cb.s_msg_list = NULL;
}