#include <stdio.h> // debugging output
#include <stdlib.h>

#include "dice.h"
#include "pline.h"
#include "stdio-util.h" // debugging output

#include "damage.h"

static DMGELT *new_dmgelt(void)
{
 DMGELT *e;

 e = malloc(sizeof(DMGELT));
 e->link = 0;
 e->hp = 0;
 e->kind = DK_ERROR;
 e->flags = 0;
 return(e);
}

static const char *dmgkind_str(DMGKIND k)
{
 static char bad[64];

 switch (k)
  { case DK_ERROR:    return("ERROR");    break;
    case DK_ORDINARY: return("ORDINARY"); break;
    case DK_FIRE:     return("FIRE");     break;
    case DK_COLD:     return("COLD");     break;
    case DK_ELECTRIC: return("ELECTRIC"); break;
  }
 sprintf(&bad[0],"?%d",(int)k);
 return(&bad[0]);
}

static const char *dmgflags_str(unsigned int flags)
{
 FILE *f;
 static char *s = 0;
 const char *p;
 static const struct {
		unsigned int b;
		const char *s;
		} bits[] = { { DF_TIMEONLY, "TIMEONLY" },
			     { DF_MAGICONLY, "MAGICONLY" },
			     { DF_NOREDUCTION, "NOREDUCTION" },
			     { 0, 0 } };
 int i;

 free(s);
 f = fopenmalloc(&s,0);
 fprintf(f,"<");
 p = "";
 for (i=0;bits[i].s;i++)
  { if (flags & bits[i].b)
     { fprintf(f,"%s%s",p,bits[i].s);
       p = "|";
       flags &= ~bits[i].b;
     }
  }
 if (flags) fprintf(f,"%s0x%x",p,flags);
 fprintf(f,">");
 fclose(f);
 return(s);
}

DAMAGE damage_add(DAMAGE a, DAMAGE b)
{
 DMGELT *e;
 DMGELT *e2;
 DMGELT *f;

 for <"b"> (e=b.elts;e;e=e2)
  { e2 = e->link;
    for (f=a.elts;f;f=f->link)
     { if ((f->kind == e->kind) && (f->flags == e->flags))
	{ f->hp += e->hp;
	  free(e);
	  continue <"b">;
	}
     }
    e->link = a.elts;
    a.elts = e;
  }
 return(a);
}

void damage_free(DAMAGE d)
{
 DMGELT *e;

 while ((e = d.elts))
  { d.elts = e->link;
    free(e);
  }
}

DAMAGE damage_simple(int hp, DMGKIND k, unsigned int flags)
{
 DMGELT *e;

 e = new_dmgelt();
 e->link = 0;
 e->hp = hp;
 e->kind = k;
 e->flags = flags;
 return((DAMAGE){.elts=e});
}

int damage_total(DAMAGE d)
{
 int t;
 DMGELT *e;

 t = 0;
 for (e=d.elts;e;e=e->link) t += e->hp;
 return(t);
}

void damage_reduction(DAMAGE *dp, int hp)
{
 int t;
 int tr;
 DMGELT *e;
 DMGELT **ep;
 int ne;
 int r;
 static FILE *f = 0;

 if (! f) f = fopen("dr.dbg","w");
 fprintf(f,"DR:");
 for (e=dp->elts;e;e=e->link) fprintf(f," <hp=%d,k=%s,f=%s>",e->hp,dmgkind_str(e->kind),dmgflags_str(e->flags));
 fprintf(f," -%d\n",hp);
 t = 0;
 ne = 0;
 for (e=dp->elts;e;e=e->link)
  { if (e->flags & DF_NOREDUCTION) continue;
    t += e->hp;
    ne ++;
  }
 if (hp > t) hp = t;
 tr = 0;
 for (e=dp->elts;e;e=e->link)
  { if (e->flags & DF_NOREDUCTION) continue;
    r = (hp * e->hp) / t;
    if (r > e->hp) r = e->hp;
    tr += r;
    fprintf(f,"%d->%d\n",e->hp,e->hp-r);
    e->hp -= r;
  }
 hp -= tr;
 fprintf(f,"%d left over\n",hp);
 ep = &dp->elts;
 while ((e = *ep))
  { if (e->hp == 0)
     { *ep = e->link;
       fprintf(f,"dropping zero elt k=%s f=%s\n",dmgkind_str(e->kind),dmgflags_str(e->flags));
       free(e);
     }
    else
     { ep = &e->link;
     }
  }
}