#include "ocilib.h"

#if defined(_WINDOWS)
    #define sleep(x) Sleep(x*1000)
#else
    #include <unistd.h>
#endif

#define wait_for_events() sleep(5)

void event_handler(OCI_Event *event);
void error_handler(OCI_Error *err);

int main(void)
{
    OCI_Connection   *con;
    OCI_Subscription *sub;
    OCI_Statement    *st;

    printf("=> Initializing OCILIB in event mode...\n\n");

    if (!OCI_Initialize(error_handler, NULL, OCI_ENV_EVENTS))
    {
        return EXIT_FAILURE;
    }

    printf("=> Connecting to usr@db...\n\n");

    con = OCI_ConnectionCreate("db", "usr", "pwd", OCI_SESSION_DEFAULT);

    OCI_SetAutoCommit(con, TRUE);

    printf("=> Creating statement...\n\n");

    st = OCI_StatementCreate(con);

    printf("=> Creating tables...\n\n");

    OCI_ExecuteStmt(st, "create table table1(code number)");
    OCI_ExecuteStmt(st, "create table table2(str varchar2(10))");

    printf("=> Registering subscription...\n\n");

    sub = OCI_SubscriptionRegister(con, "sub-00", OCI_CNT_ALL, event_handler, 5468, 0);

    printf("=> Adding queries to be notified...\n\n");

    OCI_Prepare(st, "select * from table1");
    OCI_SubscriptionAddStatement(sub, st);

    OCI_Prepare(st, "select * from table2");
    OCI_SubscriptionAddStatement(sub, st);

    printf("=> Executing some DDL operation...\n\n");

    OCI_ExecuteStmt(st, "alter table table1 add price number");

    wait_for_events();

    printf("=> Executing some DML operation...\n\n");

    OCI_ExecuteStmt(st, "insert into table1 values(1, 10.5)");
    OCI_ExecuteStmt(st, "insert into table2 values('shoes')");

    OCI_ExecuteStmt(st, "update table1 set price = 13.5 where code = 1");
    OCI_ExecuteStmt(st, "delete from table2 ");

    wait_for_events();

    printf("=> Droping tables...\n\n");

    OCI_ExecuteStmt(st, "drop table table1");
    OCI_ExecuteStmt(st, "drop table table2");

    wait_for_events();

    printf("=> Unregistering subscription...\n\n");

    OCI_SubscriptionUnregister(sub);

    printf("=> Disconnecting from DB...\n\n");

    OCI_ConnectionFree(con);

    printf("=> Cleaning up OCILIB resources...\n\n");

    OCI_Cleanup();

    printf("=> Done...\n\n");

    return EXIT_SUCCESS;
}

void error_handler(OCI_Error *err)
{
    int         err_type = OCI_ErrorGetType(err);
    const char *err_msg = OCI_ErrorGetString(err);

    printf("** %s - %s\n", err_type == OCI_ERR_WARNING ? "Warning" : "Error", err_msg);
}

void event_handler(OCI_Event *event)
{
    unsigned int type = OCI_EventGetType(event);
    unsigned int op = OCI_EventGetOperation(event);
    OCI_Subscription *sub = OCI_EventGetSubscription(event);

    printf("** Notification      : %s\n\n", OCI_SubscriptionGetName(sub));
    printf("...... Database      : %s\n", OCI_EventGetDatabase(event));

    switch (type)
    {
    case OCI_ENT_STARTUP:
        printf("...... Event         : Startup\n");
        break;
    case OCI_ENT_SHUTDOWN:
        printf("...... Event         : Shutdown\n");
        break;
    case OCI_ENT_SHUTDOWN_ANY:
        printf("...... Event         : Shutdown any\n");
        break;
    case OCI_ENT_DROP_DATABASE:
        printf("...... Event         : drop database\n");
        break;
    case OCI_ENT_DEREGISTER:
        printf("...... Event         : deregister\n");
        break;
    case OCI_ENT_OBJECT_CHANGED:

        printf("...... Event         : object changed\n");
        printf("........... Object   : %s\n", OCI_EventGetObject(event));

        switch (op)
        {
        case OCI_ONT_INSERT:
            printf("........... Action   : insert\n");
            break;
        case OCI_ONT_UPDATE:
            printf("........... Action   : update\n");
            break;
        case OCI_ONT_DELETE:
            printf("........... Action   : delete\n");
            break;
        case OCI_ONT_ALTER:
            printf("........... Action   : alter\n");
            break;
        case OCI_ONT_DROP:
            printf("........... Action   : drop\n");
            break;
        }

        if (op < OCI_ONT_ALTER)
            printf("........... Rowid    : %s\n", OCI_EventGetRowid(event));

        break;
    }

    printf("\n");
}
