/* scada.c — simulates a SCADA control center */

#include <stdlib.h>
#include <stdbool.h>
#include <stdio.h>
#include <signal.h>
#include <string.h>

#include "cs104_connection.h"
#include "hal_thread.h"
#include "hal_time.h"

static bool running = true;

void sigint_handler(int s) { running = false; }

/* ── called for every ASDU received from RTU ───────────────── */
static bool asduReceivedHandler(void* p, int address, CS101_ASDU asdu) {
    int typeId = CS101_ASDU_getTypeID(asdu);
    int cot    = CS101_ASDU_getCOT(asdu);

    /* measured float value M_ME_NC_1 */
    if (typeId == M_ME_NC_1) {
        int i;
        for (i = 0; i < CS101_ASDU_getNumberOfElements(asdu); i++) {
            MeasuredValueShort mv = (MeasuredValueShort)
                CS101_ASDU_getElement(asdu, i);
            int   ioa   = InformationObject_getObjectAddress((InformationObject)mv);
            float value = MeasuredValueShort_getValue(mv);
            InformationObject_destroy((InformationObject)mv);

            if (ioa == 100)
                printf("[SCADA ←] Voltage  IOA=100  %.2f kV\n", value);
            else if (ioa == 101)
                printf("[SCADA ←] Current  IOA=101  %.1f A\n", value);
            else
                printf("[SCADA ←] Float    IOA=%d   %.2f\n", ioa, value);
        }
    }

    /* single point M_SP_NA_1 */
    else if (typeId == M_SP_NA_1) {
        int i;
        for (i = 0; i < CS101_ASDU_getNumberOfElements(asdu); i++) {
            SinglePointInformation sp = (SinglePointInformation)
                CS101_ASDU_getElement(asdu, i);
            int  ioa   = InformationObject_getObjectAddress((InformationObject)sp);
            bool state = SinglePointInformation_getValue(sp);
            InformationObject_destroy((InformationObject)sp);

            if (ioa == 200)
                printf("[SCADA ←] Breaker1 IOA=200  %s\n", state ? "ON" : "OFF");
            else if (ioa == 201)
                printf("[SCADA ←] Breaker2 IOA=201  %s\n", state ? "ON" : "OFF");
            else
                printf("[SCADA ←] Point    IOA=%d   %s\n", ioa, state ? "ON" : "OFF");
        }
    }

    /* command confirmation */
    else if (typeId == C_SC_NA_1) {
        if (cot == CS101_COT_ACTIVATION_CON)
            printf("[SCADA ←] Command confirmed by RTU\n");
        else if (cot == CS101_COT_UNKNOWN_IOA)
            printf("[SCADA ←] Command rejected — unknown IOA\n");
    }

    else {
        printf("[SCADA ←] TypeID=%d COT=%d\n", typeId, cot);
    }

    return true;
}

/* ── connection state ───────────────────────────────────────── */
static void connectionHandler(void* p, CS104_Connection con, CS104_ConnectionEvent event) {
    if (event == CS104_CONNECTION_OPENED)
        printf("[SCADA] Connected to RTU\n");
    else if (event == CS104_CONNECTION_CLOSED)
        printf("[SCADA] Disconnected from RTU\n");
    else if (event == CS104_CONNECTION_STARTDT_CON_RECEIVED)
        printf("[SCADA] STARTDT confirmed — data transfer active\n");
    else if (event == CS104_CONNECTION_STOPDT_CON_RECEIVED)
        printf("[SCADA] STOPDT confirmed\n");
}

/* ── send a single command to RTU ───────────────────────────── */
void send_command(CS104_Connection con, int ioa, bool state) {
    CS101_AppLayerParameters alParams =
        CS104_Connection_getAppLayerParameters(con);

    CS101_ASDU asdu = CS101_ASDU_create(alParams, false,
        CS101_COT_ACTIVATION, 0, 1, false, false);

    InformationObject io = (InformationObject)
        SingleCommand_create(NULL, ioa, state, false, 0);

    CS101_ASDU_addInformationObject(asdu, io);
    InformationObject_destroy(io);

    CS104_Connection_sendASDU(con, asdu);
    CS101_ASDU_destroy(asdu);

    printf("[SCADA →] Command sent — IOA=%d state=%s\n",
           ioa, state ? "ON" : "OFF");
}

/* ── send general interrogation ─────────────────────────────── */
void send_gi(CS104_Connection con) {
    CS104_Connection_sendInterrogationCommand(con,
        CS101_COT_ACTIVATION, 1, IEC60870_QOI_STATION);
    printf("[SCADA →] General Interrogation sent\n");
}

/* ── main ───────────────────────────────────────────────────── */
int main(int argc, char** argv) {
    signal(SIGINT, sigint_handler);

    const char* ip = (argc > 1) ? argv[1] : "127.0.0.1";

    printf("[SCADA] Connecting to RTU at %s:2404\n\n", ip);

    CS104_Connection con = CS104_Connection_create(ip, 2404);

    CS104_Connection_setConnectionHandler(con, connectionHandler, NULL);
    CS104_Connection_setASDUReceivedHandler(con, asduReceivedHandler, NULL);

    CS104_Connection_connect(con);
    Thread_sleep(1000);

    /* start data transfer */
    CS104_Connection_sendStartDT(con);
    Thread_sleep(500);

    /* request all current values */
    send_gi(con);
    Thread_sleep(2000);

    /* main loop — send commands periodically */
    uint64_t lastCmd  = 0;
    bool     b1_state = false;
    bool     b2_state = false;

    printf("\n[SCADA] Running — commands every 5s, Ctrl+C to stop\n\n");

    while (running) {
        uint64_t now = Hal_getMonotonicTimeInMs();

        /* every 5s — toggle breaker1 then breaker2 alternately */
        if (now >= lastCmd + 5000) {
            lastCmd = now;

            static int cmd_count = 0;
            cmd_count++;

            if (cmd_count % 2 == 0) {
                b1_state = !b1_state;
                send_command(con, 200, b1_state);   /* toggle breaker1 */
            } else {
                b2_state = !b2_state;
                send_command(con, 201, b2_state);   /* toggle breaker2 */
            }
        }

        Thread_sleep(10);
    }

    printf("\n[SCADA] Shutting down\n");
    CS104_Connection_sendStopDT(con);
    Thread_sleep(500);
    CS104_Connection_destroy(con);
    return 0;
}