#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#include <strings.h>
#include <sys/time.h>

#include "deconst.h"
#include "conflib.h"
#include "currlib.h"

extern const char *__progname;

typedef struct date DATE;
typedef struct str STR;

struct date {
  unsigned int year : 12;
#define MAXYEAR ((1<<12)-1)
  unsigned int month : 4;
  unsigned int day : 5;
  } ;

struct str {
  char *s;
  int l;
  } ;

static STR line = { 0, 0 };
static DATE date;
static DATE edate;
static STR flags;
static STR category;
static STR from;
static STR to;
static STR amount;
static char *currency;
static long int amt;
static const char *def_curr;
static void *conf;

static char *bindex(const char *str, int len, char c)
{
 char *s;

 s = deconst(str);
 for (;len>0;s++,len--) if (*s == c) return(s);
 return(0);
}

static void handleargs(int ac, char **av, int early)
{
 int skip;
 int errs;

 skip = 0;
 errs = 0;
 for (ac--,av++;ac;ac--,av++)
  { if (skip > 0)
     { skip --;
       continue;
     }
    if (**av != '-')
     { if (! early) conf_read(conf,*av,0);
       continue;
     }
    if (0)
     {
needarg:;
       fprintf(stderr,"%s: %s needs a following argument\n",__progname,*av);
       errs ++;
       continue;
     }
#define WANTARG() do { if (++skip >= ac) goto needarg; } while (0)
    if (!strcmp(*av,"-config"))
     { WANTARG();
       if (! early) conf_read(conf,av[skip],0);
       continue;
     }
    if (!strcmp(*av,"-configline") || !strcmp(*av,"-set"))
     { WANTARG();
       if (early) conf_line(conf,av[skip],0);
       continue;
     }
#undef WANTARG
    fprintf(stderr,"%s: unrecognized option `%s'\n",__progname,*av);
    errs ++;
  }
 if (errs)
  { fprintf(stderr,"Usage: %s [options] [config-file]\n",__progname);
    exit(1);
  }
}

static inline unsigned int const monthdays(unsigned int m, unsigned int y)
{
 if (m == 2)
  { if (y % 4) return(28);
    if (y % 100) return(29);
    if (y % 400) return(28);
    return(29);
  }
       /* JanFebMarAprMayJunJulAugSepOctNovDec */
 return(" \37\00\37\36\37\36\37\37\36\37\36\37"[m]);
}

static int trans_date(const char *bp, DATE *dp)
{
 int i;
 unsigned int y;
 unsigned int m;
 unsigned int d;

 d = 0;
 for (i=0;i<8;i++)
  { if ((bp[i] < '0') || (bp[i] > '9')) return(0);
    d = (10 * d) + (bp[i] - '0');
  }
 y = d / 10000;
 m = (d / 100) % 100;
 d %= 100;
 if (y > MAXYEAR) return(0);
 if ((m < 1) || (m > 12)) return(0);
 if ((d < 1) || (d > monthdays(m,y))) return(0);
 dp->year = y;
 dp->month = m;
 dp->day = d;
 return(1);
}

static int cvtamt(STR *s, long int *amt)
{
 int i;
 int neg;
 long int a;

 neg = 0;
 i = 0;
 if (s->s[i] == '-')
  { neg = 1;
    i ++;
  }
 a = 0;
 for (;i<s->l;i++)
  { if ((s->s[i] < '0') || (s->s[i] > '9')) return(1);
    a = (a * 10) + (s->s[i] - '0');
  }
 if (neg) a = - a;
 *amt = a;
 return(0);
}

static int parse_trans(void)
{
 int l;
 char *c0;
 char *c1;
 char *c2;
 char *c3;
 char *c4;

 l = line.l;
 if (l < 22) return(0);
 if ((line.s[8] != ':') || (line.s[17] != ':')) return(0);
 if (!trans_date(line.s,&date) || !trans_date(line.s+9,&edate)) return(0);
 l -= 18;
 c0 = bindex(line.s+18,l,':');
 if (c0 == 0) return(0);
 l -= c0 - (line.s+18);
 flags.s = line.s + 18;
 flags.l = c0 - flags.s;
 c1 = bindex(c0+1,l-1,':');
 if (c1 == 0) return(0);
 l -= c1 - c0;
 category.s = c0 + 1;
 category.l = c1 - category.s;
 c2 = bindex(c1+1,l-1,':');
 if (c2 == 0) return(0);
 l -= c2 - c1;
 from.s = c1 + 1;
 from.l = c2 - from.s;
 c3 = bindex(c2+1,l-1,':');
 if (c3 == 0) return(0);
 l -= c3 - c2;
 to.s = c2 + 1;
 to.l = c3 - to.s;
 c4 = bindex(c3+1,l-1,':');
 if (currency) free(currency);
 if (c4 == 0)
  { amount.s = c3 + 1;
    amount.l = l - 1;
    currency = 0;
    c4 = c3;
  }
 else
  { l -= c4 - c3;
    amount.s = c3 + 1;
    amount.l = c4 - amount.s;
    currency = malloc(l);
    bcopy(c4+1,currency,l-1);
    currency[l-1] = '\0';
  }
 if (l < 2) return(0);
 if (c4+l != line.s+line.l) abort();
 if (cvtamt(&amount,&amt)) return(0);
 return(1);
}

static int read_trans(void)
{
 int c;
 char *buf;
 int have;
 int len;

 buf = 0;
 have = 0;
 len = 0;
 while (1)
  { c = getchar();
    if (c == EOF)
     { if (len > 0)
	{ fprintf(stderr,"%s: warning: unterminated last line ignored\n",__progname);
	}
       return(0);
     }
    if (c == '\n')
     { free(line.s);
       line.s = buf;
       line.l = len;
       if (parse_trans()) return(1);
       fprintf(stderr,"%s: warning: malformed input line ignored: ",__progname);
       fwrite(line.s,1,line.l,stderr);
       fprintf(stderr,"\n");
       buf = 0;
       have = 0;
       len = 0;
       continue;
     }
    while (len >= have) buf = realloc(buf,have+=8);
    buf[len++] = c;
  }
}

static void format_trans(void)
{
 static char *amtbuf = 0;
 static int amthave = 0;
 int fmtsize;

 if (!currency && !def_curr)
  { fprintf(stderr,"%s: no default currency configured and no currency in entry\n",__progname);
    return;
  }
 printf("%04d %02d %02d: ",date.year,date.month,date.day);
 if (flags.l)
  { putchar('[');
    fwrite(flags.s,1,flags.l,stdout);
    printf("] ");
  }
 fwrite(category.s,1,category.l,stdout);
 printf(": ");
 if (from.l) fwrite(from.s,1,from.l,stdout); else printf("(world)");
 fmtsize = format_amount(0,amt<0,(amt<0)?-amt:amt,currency?currency:def_curr);
 if (fmtsize > amthave)
  { free(amtbuf);
    amthave = fmtsize + 1;
    amtbuf = malloc(amthave);
  }
 format_amount(amtbuf,amt<0,(amt<0)?-amt:amt,currency?currency:def_curr);
 printf(" -> %s -> ",amtbuf);
 if (to.l) fwrite(to.s,1,to.l,stdout); else printf("(world)");
 printf("\n");
}

static void init_curr(void)
{
 const char *curr_file;

 curr_file = conf_path(conf,"currencies",0);
 if (curr_file)
  { load_currencies(curr_file,0);
  }
 else
  { fake_currencies();
  }
 def_curr = conf_value(conf,"defcurrency",0);
 if (def_curr && !find_currency(def_curr))
  { fprintf(stderr,"%s: default currency of %s isn't a known currency!\n",__progname,def_curr);
    exit(1);
  }
}

int main(int, char **);
int main(int ac, char **av)
{
 conf = conf_newstate();
 handleargs(ac,av,1);
 handleargs(ac,av,0);
 conf_check_env(conf,"MDB_CONFIG_DB",0);
 init_curr();
 while (read_trans()) format_trans();
 exit(0);
}