/*
 * This file is part of libbluray
 * Copyright (C) 2009-2010  Obliter0n
 * Copyright (C) 2009-2010  John Stebbins
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library. If not, see
 * <http://www.gnu.org/licenses/>.
 */

#if HAVE_CONFIG_H
#include "config.h"
#endif

#include "logging.h"

#include "file/file.h"

#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#include <string.h>

uint32_t            debug_mask = (uint32_t)-1; /* set all bits to make sure bd_debug() is called for initialization */
static BD_LOG_FUNC  log_func   = NULL;

void bd_set_debug_handler(BD_LOG_FUNC f)
{
    log_func = f;
}

void bd_set_debug_mask(uint32_t mask)
{
    debug_mask = mask;
}

uint32_t bd_get_debug_mask(void)
{
    return debug_mask;
}

void bd_debug(const char *file, int line, uint32_t mask, const char *format, ...)
{
    static int   debug_init = 0, debug_file = 0;
    static FILE *logfile    = NULL;

    // Only call getenv() once.
    if (!debug_init) {
        debug_init = 1;
        logfile = stderr;

        char *env = NULL;
        if (debug_mask == (uint32_t)-1) {
            /* might be set by application with bd_set_debug_mask() */
            debug_mask = DBG_CRIT;
        }
        if ((env = getenv("BD_DEBUG_MASK")))
            debug_mask = strtol(env, NULL, 0);

        // Send DEBUG to file?
        if ((env = getenv("BD_DEBUG_FILE"))) {
            FILE *fp = fopen(env, "wb");
            if (fp) {
                logfile = fp;
                setvbuf(logfile, NULL, _IONBF, 0);
                debug_file = 1;
            } else {
                fprintf(logfile, "%s:%d: Error opening log file %s\n", __FILE__, __LINE__, env);
            }
        }
    }

    if (mask & debug_mask) {
        const char *f = strrchr(file, DIR_SEP_CHAR);
        char buffer[4096];
        va_list args;
        int len, len2;
        BD_LOG_FUNC lf;

        len = sprintf(buffer, "%s:%d: ", f ? f + 1 : file, line);
        if (len < 0) {
            return;
        }

        va_start(args, format);
        len2 = vsnprintf(buffer + len, sizeof(buffer) - len - 1, format, args);
        va_end(args);

        if (len2 < 0) {
            return;
        }
        lf = log_func;
        if (lf) {
            buffer[sizeof(buffer)-1] = 0;
            lf(buffer);
        }

        if (!lf || debug_file) {
            len += len2;
            if ((size_t)len >= sizeof(buffer)) {
                len = sizeof(buffer);
            }

            fwrite(buffer, len, 1, logfile);
        }
    }
}