/* vi: set ts=2:
+-------------------+  Christian Schlittchen <corwin@amber.kn-bremen.de>
|                   |  Enno Rehling <enno@eressea.de>
| Eressea PBEM host |  Katja Zedel <katze@felidae.kn-bremen.de>
| (c) 1998 - 2003   |  Henning Peters <faroul@beyond.kn-bremen.de>
|                   |  Ingo Wilken <Ingo.Wilken@informatik.uni-oldenburg.de>
+-------------------+  Stefan Reich <reich@halbling.de>

This program may not be used, modified or distributed 
without prior permission by the authors of Eressea.
*/
#include <platform.h>
#include "log.h"
#include "unicode.h"

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

/* TODO: set from external function */
int log_flags = LOG_FLUSH | LOG_CPERROR | LOG_CPWARNING | LOG_CPDEBUG;
#ifdef STDIO_CP
static int stdio_codepage = STDIO_CP;
#else
static int stdio_codepage = 0;
#endif
static FILE *logfile;

#define MAXLENGTH 4096          /* because I am lazy, CP437 output is limited to this many chars */
void log_flush(void)
{
  fflush(logfile);
}

void log_puts(const char *str)
{
  fflush(stdout);
  if (!logfile)
    logfile = stderr;
  fputs(str, logfile);
}

static int
cp_convert(const char *format, char *buffer, size_t length, int codepage)
{
  /* when console output on MSDOS, convert to codepage */
  const char *input = format;
  char *pos = buffer;

  while (pos + 1 < buffer + length && *input) {
    size_t length = 0;
    int result = 0;
    if (codepage == 437) {
      result = unicode_utf8_to_cp437(pos, input, &length);
    } else if (codepage == 1252) {
      result = unicode_utf8_to_cp1252(pos, input, &length);
    }
    if (result != 0) {
      *pos = 0;                 /* just in case caller ignores our return value */
      return result;
    }
    ++pos;
    input += length;
  }
  *pos = 0;
  return 0;
}

void log_printf(const char *format, ...)
{
  va_list marker;
  if (!logfile)
    logfile = stderr;
  va_start(marker, format);
  vfprintf(logfile, format, marker);
  va_end(marker);
  if (log_flags & LOG_FLUSH) {
    log_flush();
  }
}

void log_stdio(FILE * io, const char *format, ...)
{
  va_list marker;
  if (!logfile)
    logfile = stderr;
  va_start(marker, format);
  if (stdio_codepage) {
    char buffer[MAXLENGTH];
    char converted[MAXLENGTH];

    vsnprintf(buffer, sizeof(buffer), format, marker);
    if (cp_convert(buffer, converted, MAXLENGTH, stdio_codepage) == 0) {
      fputs(converted, stderr);
    } else {
      /* fall back to non-converted output */
      va_end(marker);
      va_start(marker, format);
      vfprintf(io, format, marker);
    }
  } else {
    vfprintf(io, format, marker);
  }
  va_end(marker);
  if (log_flags & LOG_FLUSH) {
    log_flush();
  }
}

void log_open(const char *filename)
{
  if (logfile)
    log_close();
  logfile = fopen(filename, "a");
  if (logfile) {
    /* Get UNIX-style time and display as number and string. */
    time_t ltime;
    time(&ltime);
    log_printf("===\n=== Logfile started at %s===\n", ctime(&ltime));
  }
}

void log_close(void)
{
  if (!logfile || logfile == stderr || logfile == stdout)
    return;
  if (logfile) {
    /* Get UNIX-style time and display as number and string. */
    time_t ltime;
    time(&ltime);
    log_printf("===\n=== Logfile closed at %s===\n\n", ctime(&ltime));
  }
  fclose(logfile);
  logfile = 0;
}

static int check_dupe(const char *format, const char *type)
{
  static const char *last_type; /* STATIC_XCALL: used across calls */
  static char last_message[32]; /* STATIC_XCALL: used across calls */
  static int dupes = 0;         /* STATIC_XCALL: used across calls */
  if (strncmp(last_message, format, sizeof(last_message)) == 0) {
    ++dupes;
    return 1;
  }
  if (dupes) {
    if (log_flags & LOG_CPERROR) {
      fprintf(stderr, "%s: last message repeated %d times\n", last_type,
        dupes + 1);
    }
    dupes = 0;
  }
  strncpy(last_message, format, sizeof(last_message));
  last_type = type;
  return 0;
}

void _log_debug(const char *format, ...)
{
  if (log_flags & LOG_CPDEBUG) {
    int dupe = check_dupe(format, "DEBUG");

    fflush(stdout);
    if (!logfile)
      logfile = stderr;
    if (logfile != stderr) {
      va_list marker;
      fputs("DEBUG: ", logfile);
      va_start(marker, format);
      vfprintf(logfile, format, marker);
      va_end(marker);
    }
    if (!dupe) {
      va_list marker;
      fputs("DEBUG: ", stderr);
      va_start(marker, format);
      if (stdio_codepage) {
        char buffer[MAXLENGTH];
        char converted[MAXLENGTH];

        vsnprintf(buffer, sizeof(buffer), format, marker);
        if (cp_convert(buffer, converted, MAXLENGTH, stdio_codepage) == 0) {
          fputs(converted, stderr);
        } else {
          /* fall back to non-converted output */
          va_end(marker);
          va_start(marker, format);
          vfprintf(stderr, format, marker);
        }
      } else {
        vfprintf(stderr, format, marker);
      }
      va_end(marker);
    }
    if (log_flags & LOG_FLUSH) {
      log_flush();
    }
  }
}

void _log_warn(const char *format, ...)
{
  if (log_flags & LOG_CPWARNING) {
    int dupe = check_dupe(format, "WARNING");

    fflush(stdout);
    if (!logfile)
      logfile = stderr;
    if (logfile != stderr) {
      va_list marker;
      fputs("WARNING: ", logfile);
      va_start(marker, format);
      vfprintf(logfile, format, marker);
      va_end(marker);
    }
    if (!dupe) {
      va_list marker;
      fputs("WARNING: ", stderr);
      va_start(marker, format);
      if (stdio_codepage) {
        char buffer[MAXLENGTH];
        char converted[MAXLENGTH];

        vsnprintf(buffer, sizeof(buffer), format, marker);
        if (cp_convert(buffer, converted, MAXLENGTH, stdio_codepage) == 0) {
          fputs(converted, stderr);
        } else {
          /* fall back to non-converted output */
          va_end(marker);
          va_start(marker, format);
          vfprintf(stderr, format, marker);
        }
      } else {
        vfprintf(stderr, format, marker);
      }
      va_end(marker);
    }
    if (log_flags & LOG_FLUSH) {
      log_flush();
    }
  }
}

void _log_error(const char *format, ...)
{
  int dupe = check_dupe(format, "ERROR");
  fflush(stdout);
  if (!logfile)
    logfile = stderr;

  if (logfile != stderr) {
    va_list marker;
    fputs("ERROR: ", logfile);
    va_start(marker, format);
    vfprintf(logfile, format, marker);
    va_end(marker);
  }
  if (!dupe) {
    if (logfile != stderr) {
      if (log_flags & LOG_CPERROR) {
        va_list marker;

        fputs("ERROR: ", stderr);
        va_start(marker, format);
        if (stdio_codepage) {
          char buffer[MAXLENGTH];
          char converted[MAXLENGTH];

          vsnprintf(buffer, sizeof(buffer), format, marker);
          if (cp_convert(buffer, converted, MAXLENGTH, stdio_codepage) == 0) {
            fputs(converted, stderr);
          } else {
            /* fall back to non-converted output */
            va_end(marker);
            va_start(marker, format);
            vfprintf(stderr, format, marker);
          }
        } else {
          vfprintf(stderr, format, marker);
        }
        va_end(marker);
      }
      log_flush();
    }
  }
}

static unsigned int logfile_level = 0;
static unsigned int stderr_level = 1;

void _log_info(unsigned int level, const char *format, ...)
{
  va_list marker;
  fflush(stdout);
  if (!logfile)
    logfile = stderr;
  if (logfile_level >= level) {
    fprintf(logfile, "INFO[%u]: ", level);
    va_start(marker, format);
    vfprintf(logfile, format, marker);
    va_end(marker);
    if (logfile != stderr) {
      if (stderr_level >= level) {
        fprintf(stderr, "INFO[%u]: ", level);
        va_start(marker, format);
        if (stdio_codepage) {
          char buffer[MAXLENGTH];
          char converted[MAXLENGTH];

          vsnprintf(buffer, sizeof(buffer), format, marker);
          if (cp_convert(buffer, converted, MAXLENGTH, stdio_codepage) == 0) {
            fputs(converted, stderr);
          } else {
            /* fall back to non-converted output */
            va_end(marker);
            va_start(marker, format);
            vfprintf(stderr, format, marker);
          }
        } else {
          vfprintf(stderr, format, marker);
        }
        va_end(marker);
      }
      if (log_flags & LOG_FLUSH) {
        log_flush();
      }
    }
  }
}