/* $Id$ */
#include "bbs.h"

static int headers_size = 0;
static fileheader_t *headers = NULL;
static int      last_line; // PTT: last_line 游標可指的最後一個

#include <sys/mman.h>

/* ----------------------------------------------------- */
/* Tag List 標籤                                         */
/* ----------------------------------------------------- */
static TagItem         *TagList = NULL;	/* ascending list */

/**
 * @param locus
 * @return void
 */
void
UnTagger(int locus)
{
    if (locus > TagNum || TagNum <= 0)
	return;

    TagNum--;

    if (TagNum > locus)
	memmove(&TagList[locus], &TagList[locus + 1],
	       (TagNum - locus) * sizeof(TagItem));
}

int
Tagger(time4_t chrono, int recno, int mode)
{
    int             head, tail, posi = 0, comp;

    if(TagList == NULL) {
	TagList = malloc(sizeof(TagItem)*(MAXTAGS+1));
    }

    for (head = 0, tail = TagNum - 1, comp = 1; head <= tail;) {
	posi = (head + tail) >> 1;
	comp = TagList[posi].chrono - chrono;
	if (!comp) {
	    break;
	} else if (comp < 0) {
	    head = posi + 1;
	} else {
	    tail = posi - 1;
	}
    }

    if (mode == TAG_NIN) {
	if (!comp && recno)	/* 絕對嚴謹：連 recno 一起比對 */
	    comp = recno - TagList[posi].recno;
	return comp;

    }
    if (!comp) {
	if (mode != TAG_TOGGLE || TagNum <= 0)
	    return NA;

	TagNum--;
	memmove(&TagList[posi], &TagList[posi + 1],
	       (TagNum - posi) * sizeof(TagItem));
    } else if (TagNum < MAXTAGS) {
	TagItem        *tagp;

	memmove(&TagList[head+1], &TagList[head], sizeof(TagItem)*(TagNum-head));
	tagp = &TagList[head];
	tagp->chrono = chrono;
	tagp->recno = recno;
	TagNum++;
    } else {
	bell();
	return 0;		/* full */
    }
    return YEA;
}

#if 0
static void
EnumTagName(char *fname, int locus) /* unused */
{
    snprintf(fname, sizeof(fname), "M.%d.A", (int)TagList[locus].chrono);
}
#endif

void
EnumTagFhdr(fileheader_t * fhdr, char *direct, int locus)
{
    get_record(direct, fhdr, sizeof(fileheader_t), TagList[locus].recno);
}

/* -1 : 取消 */
/* 0 : single article */
/* ow: whole tag list */

int
AskTag(const char *msg)
{
    int             num;

    num = TagNum;
    switch (getans("◆ %s A)文章 T)標記 Q)uit?", msg)) {
    case 'q':
	num = -1;
	break;
    case 'a':
	num = 0;
    }
    return num;
}


#include <sys/mman.h>

#define BATCH_SIZE      65536

static char           *
f_map(const char *fpath, int *fsize)
{
    int             fd, size;
    struct stat     st;
    char *map;

    if ((fd = open(fpath, O_RDONLY)) < 0)
	return (char *)-1;

    if (fstat(fd, &st) || !S_ISREG(st.st_mode) || (size = st.st_size) <= 0) {
	close(fd);
	return (char *)-1;
    }
    map = (char *)mmap(NULL, size, PROT_READ, MAP_SHARED, fd, 0);
    close(fd);
    *fsize = size;
    return map;
}


static int
TagThread(const char *direct)
{
    int             fsize, count;
    char           *title, *fimage;
    fileheader_t   *head, *tail;

    fimage = f_map(direct, &fsize);
    if (fimage == (char *)-1)
	return DONOTHING;

    head = (fileheader_t *) fimage;
    tail = (fileheader_t *) (fimage + fsize);
    count = 0;
    do {
	count++;
	title = subject(head->title);
	if (!strncmp(currtitle, title, TTLEN)) {
	    if (!Tagger(atoi(head->filename + 2), count, TAG_INSERT))
		break;
	}
    } while (++head < tail);

    munmap(fimage, fsize);
    return FULLUPDATE;
}


int
TagPruner(int bid)
{
    boardheader_t  *bp=NULL;
    assert(bid >= 0);   /* bid == 0 means in mailbox */
    if (bid){
	bp = getbcache(bid);
	if (strcmp(bp->brdname, BN_SECURITY) == 0)
	    return DONOTHING;
    }
    if (TagNum && ((currstat != READING) || (currmode & MODE_BOARD))) {
	if (getans("刪除所有標記[N]?") != 'y')
	    return READ_REDRAW;
#ifdef SAFE_ARTICLE_DELETE
        if(bp && !(currmode & MODE_DIGEST) && bp->nuser>30 )
            safe_delete_range(currdirect, 0, 0);
        else
#endif
	    delete_range(currdirect, 0, 0);
	TagNum = 0;
	if (bid)
	    setbtotal(bid);
        else if(currstat == RMAIL)
            setupmailusage();

	return NEWDIRECT;
    }
    return DONOTHING;
}


/* ----------------------------------------------------- */
/* cursor & reading record position control              */
/* ----------------------------------------------------- */
keeploc_t      *
getkeep(const char *s, int def_topline, int def_cursline)
{
    /* 為省記憶體, 且避免 malloc/free 不成對, getkeep 最好不要 malloc,
     * 只記 s 的 hash 值,
     * fvn1a-32bit collision 機率約小於十萬分之一 */
    /* 原本使用 link list, 可是一方面會造成 malloc/free 不成對, 
     * 一方面 size 小, malloc space overhead 就高, 因此改成 link block,
     * 以 KEEPSLOT 為一個 block 的 link list.
     * 只有第一個 block 可能沒滿. */
    /* TODO LRU recycle? 麻煩在於別處可能把 keeploc_t pointer 記著... */
#define KEEPSLOT 10
    struct keepsome {
	unsigned char used;
	keeploc_t arr[KEEPSLOT];
	struct keepsome *next;
    };
    static struct keepsome preserv_keepblock;
    static struct keepsome *keeplist = &preserv_keepblock;
    struct keeploc_t *p;
    unsigned key=StringHash(s);
    int i;

    if (def_cursline >= 0) {
	struct keepsome *kl=keeplist;
	while(kl) {
	    for(i=0; i<kl->used; i++)
		if(key == kl->arr[i].hashkey) {
		    p = &kl->arr[i];
		    if (p->crs_ln < 1)
			p->crs_ln = 1;
		    return p;
		}
	    kl=kl->next;
	}
    } else
	def_cursline = -def_cursline;

    if(keeplist->used==KEEPSLOT) {
	struct keepsome *kl;
	kl = (struct keepsome*)malloc(sizeof(struct keepsome));
	memset(kl, 0, sizeof(struct keepsome));
	kl->next = keeplist;
	keeplist = kl;
    }
    p = &keeplist->arr[keeplist->used];
    keeplist->used++;
    p->hashkey = key;
    p->top_ln = def_topline;
    p->crs_ln = def_cursline;
    return p;
}

void
fixkeep(const char *s, int first)
{
    keeploc_t      *k;

    k = getkeep(s, 1, 1);
    if (k->crs_ln >= first) {
	k->crs_ln = (first == 1 ? 1 : first - 1);
	k->top_ln = (first < 11 ? 1 : first - 10);
    }
}

/* calc cursor pos and show cursor correctly */
static int
cursor_pos(keeploc_t * locmem, int val, int from_top, int isshow)
{
    int  top=locmem->top_ln;
    if (!last_line){
	cursor_show(3 , 0);
	return DONOTHING;
    }
    if (val > last_line)
	val = last_line;
    if (val <= 0)
	val = 1;
    if (val >= top && val < top + headers_size) {
        if(isshow){
	    if(locmem->crs_ln >= top)
		cursor_clear(3 + locmem->crs_ln - top, 0);
	    cursor_show(3 + val - top, 0);
	}
	locmem->crs_ln = val;
	return DONOTHING;
    }
    locmem->top_ln = val - from_top;
    if (locmem->top_ln <= 0)
	locmem->top_ln = 1;
    locmem->crs_ln = val;
    return isshow ? PARTUPDATE : HEADERS_RELOAD;
}

/**
 * 根據 stypen 選擇上/下一篇文章
 *
 * @param locmem  用來存在某看板游標位置的 structure。
 * @param stypen  游標移動的方法
 *           CURSOR_FIRST, CURSOR_NEXT, CURSOR_PREV:
 *             與游標目前位置的文章同標題 的 第一篇/下一篇/前一篇 文章。
 *           RELATE_FIRST, RELATE_NEXT, RELATE_PREV:
 *             與目前正閱讀的文章同標題 的 第一篇/下一篇/前一篇 文章。
 *           NEWPOST_NEXT, NEWPOST_PREV:
 *             下一個/前一個 thread 的第一篇。
 *           AUTHOR_NEXT, AUTHOR_PREV:
 *             XXX 這功能目前好像沒用到?
 *
 * @return 新的游標位置
 */
static int
thread(const keeploc_t * locmem, int stypen)
{
    fileheader_t fh;
    int     pos = locmem->crs_ln, jump = THREAD_SEARCH_RANGE, new_ln;
    int     fd = -1, amatch = -1;
    int     step = (stypen & RS_FORWARD) ? 1 : -1;
    char    *key;

    if(locmem->crs_ln==0)
	return locmem->crs_ln;
    
    STATINC(STAT_THREAD);
    if (stypen & RS_AUTHOR)
	key = headers[pos - locmem->top_ln].owner;
    else if (stypen & RS_CURRENT)
     	key = subject(currtitle);
    else
	key = subject(headers[pos - locmem->top_ln].title );

    for( new_ln = pos + step ;
	 new_ln > 0 && new_ln <= last_line && --jump > 0;
	 new_ln += step ) {

	int rk = 
	    get_record_keep(currdirect, &fh, sizeof(fileheader_t), new_ln, &fd);

	if(fd < 0 || rk < 0)
	{
	    new_ln = pos;
	    break;
	}

        if( stypen & RS_TITLE ){
            if( stypen & RS_FIRST ){
		if( !strncmp(fh.title, key, PROPER_TITLE_LEN) )
		    break;
		else if( !strncmp(&fh.title[4], key, PROPER_TITLE_LEN) ) {
		    amatch = new_ln;
		    jump = THREAD_SEARCH_RANGE; 
		    /* 當搜尋同主題第一篇, 連續找不到多少篇才停 */
		}
	    }
            else if( !strncmp(subject(fh.title), key, PROPER_TITLE_LEN) )
		break;
	}
        else if( stypen & RS_NEWPOST ){
            if( strncmp(fh.title, "Re:", 3) )
		break;
	}
        else{  // RS_AUTHOR
            if( strcmp(subject(fh.owner), key) == EQUSTR )
		break;
	}
    }

    if( fd != -1 )
	close(fd);

    if( jump <= 0 || new_ln <= 0 || new_ln > last_line )
	new_ln = (amatch == -1 ? pos : amatch); //didn't find

    return new_ln;
}

#ifdef INTERNET_EMAIL
static void
mail_forward(const fileheader_t * fhdr, const char *direct, int mode)
{
    int             i;
    char            buf[STRLEN];
    char           *p;

    strlcpy(buf, direct, sizeof(buf));
    if ((p = strrchr(buf, '/')))
	*p = '\0';
    switch (i = doforward(buf, fhdr, mode)) {
    case 0:
	vmsg(msg_fwd_ok);
	break;
    case -1:
	vmsg(msg_fwd_err1);
	break;
    case -2:
#ifndef DEBUG_FWDADDRERR
	vmsg(msg_fwd_err2);
#endif
	break;
    case -4:
	vmsg("信箱已滿");
	break;
    default:
	break;
    }
}
#endif

// return: 1 - found, 0 - fail.
inline static int
dbcs_strcasestr(const char* pool, const char *ptr)
{
#if 0
    // old method
    int len = strlen(ptr);

    while(*pool)
    {
	// FIXME 用 strncasecmp 還是會錯
	if(strncasecmp(pool, ptr, len) == 0)
	    return 1;
	/* else */
	if(*pool < 0)
	{
	    pool ++;
	    if(*pool == 0)
		return 0;
	}
	pool ++;
    }
    return 0;

#endif

    int i = 0, i2 = 0, found = 0,
        szpool = strlen(pool),
        szptr  = strlen(ptr);

    for (i = 0; i <= szpool-szptr; i++)
    {
        found = 1;

        // compare szpool[i..szptr] with ptr
        for (i2 = 0; i2 < szptr; i2++)
        {
            if (pool[i + i2] > 0)
            {
                // ascii
                if (ptr[i2] < 0 || 
		    tolower(ptr[i2]) != tolower(pool[i+i2]))
                {
		    // printf("break on ascii (i=%d, i2=%d).\n", i, i2);
                    found = 0;
                    break;
                }
            } else {
                // non-ascii
                if (ptr[i2]   != pool[i+i2] ||
                    ptr[i2+1] != pool[i+i2+1])
                {
		    // printf("break on non-ascii (i=%d, i2=%d).\n", i, i2);
                    found = 0;
                    break;
                }
		i2 ++;
            }
        }

        if (found) break;

        // next iteration: if target is DBCS, skip one more byte.
        if (pool[i] < 0)
            i++;
    }
    return found;
}

static int
select_read(const keeploc_t * locmem, int sr_mode)
{
#define READSIZE 64  // 8192 / sizeof(fileheader_t)
   time4_t filetime;
   fileheader_t    fhs[READSIZE];
   char newdirect[PATHLEN];
   int first_select;
   char genbuf[PATHLEN], *p = strstr(currdirect, "SR.");
   static int _mode = 0;
   int reload, inc;
   int len, fd, fr, i, count = 0, reference = 0;
   int filemode;
   /* selection condition */
   char keyword[TTLEN + 1] = "";
   int n_recommend = 0, n_money = 0;


   if(locmem->crs_ln == 0)
       return locmem->crs_ln;

   first_select = p==NULL;

   STATINC(STAT_SELECTREAD);
   if(sr_mode & RS_AUTHOR)
           {
	     if(!getdata(b_lines, 0,
                 currmode & MODE_SELECT ? "增加條件 作者: ":"搜尋作者: ",
                  keyword, IDLEN+1, LCECHO))
                return READ_REDRAW; 
           }
   else if(sr_mode  & RS_KEYWORD)
          {
             if(!getdata(b_lines, 0, 
                 currmode & MODE_SELECT ? "增加條件 標題: ":"搜尋標題: ",
                 keyword, TTLEN, DOECHO))
                return READ_REDRAW;
#ifdef KEYWORD_LOG
             log_file("keyword_search_log", LOG_CREAT | LOG_VF,
		      "%s:%s\n", currboard, keyword);
#endif
          }
   else if(sr_mode  & RS_KEYWORD_EXCLUDE)
          {
	      // TTLEN width exceed default screen
	      // let's use TTLEN-4 here.
             if(!(currmode & MODE_SELECT) ||
                !getdata(b_lines, 0, "增加條件 排除標題: ", 
                 keyword, TTLEN-4, DOECHO))
                return READ_REDRAW;
          }
   else if (sr_mode  & RS_RECOMMEND)
          {
             if(currstat == RMAIL || (
	        !getdata(b_lines, 0, 
                 (currmode & MODE_SELECT) ? 
		 "增加條件 推文數: ":
		 "搜尋推文數高於多少"
#ifndef OLDRECOMMEND
		     " (<0則搜噓文數) "
#endif // OLDRECOMMEND
		 "的文章: ",
                 keyword, 7, LCECHO) || (n_recommend = atoi(keyword)) == 0 ))
                return READ_REDRAW;
	  }
   else if (sr_mode  & RS_MONEY)
          {
             if(currstat == RMAIL || (
	        !getdata(b_lines, 0, 
                 (currmode & MODE_SELECT) ?
		 "增加條件 文章價格: ":"搜尋價格高於多少的文章: ",
                 keyword, 7, LCECHO) || (n_money = atoi(keyword)) <= 0 ))
                return READ_REDRAW;
             strcat(keyword, "M");
	  }
   else {
       // Ptt: only once for these modes.
       if(!first_select && _mode & sr_mode & (RS_TITLE | RS_NEWPOST | RS_MARK | RS_SOLVED))
	   return DONOTHING;

       if(sr_mode & RS_TITLE) {
	   fileheader_t *fh = &headers[locmem->crs_ln - locmem->top_ln]; 
	   strcpy(keyword, subject(fh->title));           
       }
   }

   if(first_select)
      _mode = sr_mode;
   else
      _mode |= sr_mode;
   
   snprintf(genbuf, sizeof(genbuf), "%s%X.%X.%X",
            first_select ? "SR.":p,
            sr_mode, (int)strlen(keyword), DBCS_StringHash(keyword));
   if( strlen(genbuf) > PATHLEN - 50 )
       return  READ_REDRAW; // avoid overflow

   if (currstat == RMAIL)
       sethomefile(newdirect, cuser.userid, genbuf);
   else
       setbfile(newdirect, currboard, genbuf);

   filetime = dasht(newdirect);
   count = dashs(newdirect) / sizeof(fileheader_t);

   if (currstat != RMAIL && currboard[0] && currbid > 0)
   {
       time4_t filecreate = dashc(newdirect);
       boardheader_t *bp  = getbcache(currbid);
       assert(bp);

       if (bp->SRexpire)
       {
	   if (bp->SRexpire > now) // invalid expire time.
	       bp->SRexpire = now;

	   if (bp->SRexpire > filecreate)
	       filetime = -1;
       }
   }

   if(filetime<0 || now-filetime>60*60) {
       reload = 1;
       inc = 0;
   } else if(now-filetime > 3*60) {
       reload = 1;
       inc = 1;
   } else {
       /* use cached data */
       reload = 0;
       inc = 0;
   }

   /* mark and recommend shouldn't incremental select */
   if(sr_mode & (RS_MARK | RS_RECOMMEND | RS_SOLVED))
       inc = 0;

   if(reload) {
       if( (fr = open(currdirect, O_RDONLY, 0)) != -1 ) {
	   if(inc) {
	       /* find incremental selection start point */
	       int idx;
	       sprintf(fhs[0].filename, "X.%d", (int)filetime); 
	       idx = getindex(currdirect, &fhs[0], 0);
	       if(idx<0) {
		   reference = -idx;
	       } else if(idx==0) {
		   inc = 0;
	       } else {
		   reference = idx;
	       }
	   }
	   if(inc) {
	       filemode = O_APPEND | O_RDWR;
	   } else {
	       filemode = O_CREAT | O_RDWR;
	       count = 0;
	       reference = 0;
	   }

	   if( (fd = open(newdirect, filemode, 0600)) == -1 ) {
	       close(fr);
	       return READ_REDRAW;
	   }

	   if(reference>0)
	       lseek(fr, reference*sizeof(fileheader_t), SEEK_SET);

#ifdef DEBUG
	   vmsgf("search: %s", currdirect);
#endif
	   while( (len = read(fr, fhs, sizeof(fhs))) > 0 ){
	       len /= sizeof(fileheader_t);
	       for( i = 0 ; i < len ; ++i ){
		   reference++;
		   if( (sr_mode & RS_MARK)  &&
		       !(fhs[i].filemode & FILE_MARKED) )
		       continue;
		   if( (sr_mode & RS_SOLVED) &&
		       !(fhs[i].filemode & FILE_SOLVED) )
		       continue;
		   else if((sr_mode & RS_NEWPOST)  &&
		      !strncmp(fhs[i].title,  "Re:", 3))
		       continue;
		   else if((sr_mode & RS_AUTHOR)  &&
		      !dbcs_strcasestr(fhs[i].owner, keyword))
		       continue;
		   else if((sr_mode & RS_KEYWORD)  &&
		      !dbcs_strcasestr(fhs[i].title, keyword))
		       continue;
                   else if(sr_mode  & RS_KEYWORD_EXCLUDE &&
                       dbcs_strcasestr(fhs[i].title, keyword))
		       continue;
		   else if((sr_mode & RS_TITLE)  &&          
		      strcasecmp(subject(fhs[i].title), keyword))
		       continue;
		   else if ((sr_mode & RS_RECOMMEND)  &&
		       (n_recommend > 0 ?
		       (fhs[i].recommend < n_recommend) :
		       (fhs[i].recommend > n_recommend) ))
		       continue;
		   /* please put money test in last */
		   else if ((sr_mode & RS_MONEY) &&
			   query_file_money(fhs+i) < n_money)
		       continue;

                   if(first_select) {
		       fhs[i].multi.refer.flag = 1;
		       fhs[i].multi.refer.ref = reference;
		   }
		   ++count;
		   write(fd, &fhs[i], sizeof(fileheader_t));
	       }
	   } // end while
           close(fr);
	   ftruncate(fd, count*sizeof(fileheader_t));
	   close(fd);
       }
   }

   if(count) {
       strlcpy(currdirect, newdirect, sizeof(currdirect));
       currmode |= MODE_SELECT;
       currsrmode |= sr_mode;
       return NEWDIRECT;
   }
   return READ_REDRAW;
}

static int newdirect_new_ln = -1;

static int
i_read_key(const onekey_t * rcmdlist, keeploc_t * locmem, 
           int bid, int bottom_line)
{
    int     mode = DONOTHING, num, new_top=10;
    int     ch, new_ln = locmem->crs_ln, lastmode = DONOTHING;
    static  char default_ch = 0;
    
    do {
	if( (mode = cursor_pos(locmem, new_ln, new_top, default_ch ? 0 : 1))
	    != DONOTHING )
	    return mode;
	
	if( !default_ch )
	    ch = igetch();
	else{
	    if(new_ln != locmem->crs_ln) {// move fault
		default_ch=0;
		return FULLUPDATE;
	    }
	    ch = default_ch;
	}

	new_top = 10; // default 10 
	switch (ch) {
        case '0':    case '1':    case '2':    case '3':    case '4':
	case '5':    case '6':    case '7':    case '8':    case '9':
	    if( (num = search_num(ch, last_line)) != -1 )
		new_ln = num + 1; 
	    break;
    	case 'q':
    	case 'e':
    	case KEY_LEFT:
	    if(currmode & MODE_SELECT && locmem->crs_ln>0){
		char genbuf[PATHLEN];
		fileheader_t *fhdr = &headers[locmem->crs_ln - locmem->top_ln];
		board_select();
		setbdir(genbuf, currboard);
		locmem = getkeep(genbuf, 0, 1);
		locmem->crs_ln = fhdr->multi.refer.ref;
		num = locmem->crs_ln - p_lines + 1;
		locmem->top_ln = num < 1 ? 1 : num;
		mode =  NEWDIRECT;
	    }
	    else
		mode =  
		    (currmode & MODE_DIGEST) ? board_digest() : DOQUIT;
	    break;
	case '#':
	    {
	      char aidc[100];
	      aidu_t aidu = 0;
	      char dirfile[PATHLEN];
	      char *sp;
	      int n = -1;

	      if(!getdata(b_lines, 0, "搜尋" AID_DISPLAYNAME ": #", aidc, 20, LCECHO))
	      {
	        move(b_lines, 0);
	        clrtoeol();
	        mode = FULLUPDATE;
	        break;
	      }

	      if((currmode & MODE_SELECT) ||
	         (currstat == RMAIL))
	      {
	          move(21, 0);
	          clrtobot();
	          move(22, 0);
	          prints("此狀態下無法使用搜尋" AID_DISPLAYNAME "功\能");
	          pressanykey();
	          mode = FULLUPDATE;
	          break;
	      }

	      /* strip leading spaces and '#' */
	      sp = aidc;
	      while(*sp == ' ')
	        sp ++;
	      if(*sp == '#')
	        sp ++;

	      if((aidu = aidc2aidu(sp)) > 0)
	      {
	        /* search bottom */
	        /* FIXME: 置底文但沒列在 .DIR.bottom 的在這段會搜不到，
	                  在下一段 search board 時才會搜到本體。難解。 */
	        {
	          char buf[FNLEN];

	          snprintf(buf, FNLEN, "%s.bottom", FN_DIR);
	          setbfile(dirfile, currboard, buf);
	          if((n = search_aidu(dirfile, aidu)) >= 0)
	          {
	            n += getbtotal(currbid);
	              /* 不可用 bottom_line，因為如果是在 digest mode，
	                 bottom_line 會是文摘的數目，而不是真正的文章數 */
	            if(currmode & MODE_DIGEST)
	            {
	              newdirect_new_ln = n;

	              new_ln = locmem->crs_ln;
	                /* dirty hack for crs_ln = 1, then HOME pressed */

	              default_ch = KEY_TAB;
	              mode = DONOTHING;
	              break;
	            }
	          }
	        }
	        if(n < 0)
	        /* search board */
	        {
	          setbfile(dirfile, currboard, FN_DIR);
	          n = search_aidu(dirfile, aidu);
	          if(n >= 0 && (currmode & MODE_DIGEST))
	          /* switch to normal read mode */
	          {
	            newdirect_new_ln = n;

	            new_ln = locmem->crs_ln;
	              /* dirty hack for crs_ln = 1, then HOME pressed */

	            default_ch = KEY_TAB;
	            mode = DONOTHING;
	            break;
	          }
	        }
	        if(n < 0)
	        /* search digest */
	        {
	          setbfile(dirfile, currboard, fn_mandex);
	          n = search_aidu(dirfile, aidu);
	          if(n >= 0 && !(currmode & MODE_DIGEST))
	          /* switch to digest mode */
	          {
	            newdirect_new_ln = n;

	            new_ln = locmem->crs_ln;
	              /* dirty hack for crs_ln = 1, then HOME pressed */

	            default_ch = KEY_TAB;
	            mode = DONOTHING;
	            break;
	          }
	        }
	      }  /* if(aidu > 0) */
	      if(n < 0)
	      {
	        move(21, 0);
	        clrtobot();
	        move(22, 0);
	        if(aidu <= 0)
	          prints("不合法的" AID_DISPLAYNAME "，請確定輸入是正確的");
	        else
	          prints("找不到這個" AID_DISPLAYNAME "，可能是文章已消失，或是你找錯看板了");
	        pressanykey();
	        mode = FULLUPDATE;
	      }  /* if(n < 0) */
	      else
	      {
	        new_ln = n + 1;
	        move(b_lines, 0);
	        clrtoeol();
	        mode = DONOTHING;
	      }
	    }
	    break;
        case Ctrl('L'):
	    redrawwin();
	    refresh();
	    break;

        case Ctrl('H'):
	    mode = select_read(locmem, RS_NEWPOST);
	    break;
	    
	case 'Z':
	    mode = select_read(locmem, RS_RECOMMEND);
	    break;
		
        case 'a':
	    mode = select_read(locmem, RS_AUTHOR);
	    break;

        case 'A':
	    mode = select_read(locmem, RS_MONEY);
	    break;

        case 'G':
	    // special types
	    switch(getans( currmode & MODE_SELECT ? 
			"增加條件 標記(m/s)[m]: ":
			"搜尋標記(m/s)[m]: "))
	    {
		case 's':
		    mode = select_read(locmem, RS_SOLVED);
		    break;

		default:
		case 'm':
		    mode = select_read(locmem, RS_MARK);
		    break;
	    }
	    break;

        case '/':
        case '?':
	    mode = select_read(locmem, RS_KEYWORD);
	    break;

        case 'S':
	    mode = select_read(locmem, RS_TITLE);
	    break;

        case '!':
	    mode = select_read(locmem, RS_KEYWORD_EXCLUDE);
	    break;

        case '=':
	    new_ln = thread(locmem, RELATE_FIRST);
	    break;

        case '\\':
	    new_ln = thread(locmem, CURSOR_FIRST);
	    break;

        case ']':
	    new_ln = thread(locmem, RELATE_NEXT);
	    break;

        case '+':
	    new_ln = thread(locmem, CURSOR_NEXT);
	    break;

        case '[':
	    new_ln = thread(locmem, RELATE_PREV);
	    break;

     	case '-':
	    new_ln = thread(locmem, CURSOR_PREV);
	    break;

    	case '<':
    	case ',':
	    new_ln = thread(locmem, NEWPOST_PREV);
	    break;

    	case '.':
    	case '>':
	    new_ln = thread(locmem, NEWPOST_NEXT);
	    break;

    	case 'p':
    	case 'k':
	case KEY_UP:
	    if (locmem->crs_ln <= 1) {
		new_ln = last_line;
		new_top = p_lines-1;
	    } else {
		new_ln = locmem->crs_ln - 1; 
		new_top = p_lines - 2;
	    }
	    break;

	case 'n':
	case 'j':
	case KEY_DOWN:
	    new_ln = locmem->crs_ln + 1; 
	    new_top = 1;
	    break;

	case ' ':
	case KEY_PGDN:
	case 'N':
	case Ctrl('F'):
	    new_ln = locmem->top_ln + p_lines; 
	    new_top = 0;
	    break;

	case KEY_PGUP:
	case Ctrl('B'):
	case 'P':
	    new_ln = locmem->top_ln - p_lines; 
	    new_top = 0;
	    break;

	    /* add home(top entry) support? */
	case KEY_HOME:
	    new_ln = 0;
	    new_top = 0;
	    break;

	case KEY_END:
	case '$':
	    new_ln = last_line;
	    new_top = p_lines-1;
	    break;

	case 'F':
	case 'U':
	    if (HasUserPerm(PERM_FORWARD) && locmem->crs_ln>0) {
		mail_forward(&headers[locmem->crs_ln - locmem->top_ln],
			     currdirect, ch /* == 'U' */ );
		/* by CharlieL */
		// mode = READ_REDRAW;
		return FULLUPDATE;
	    }
	    break;

	case Ctrl('Q'):
	    if(locmem->crs_ln>0)
		mode = my_query(headers[locmem->crs_ln - locmem->top_ln].owner);
	    break;

	case Ctrl('S'):
	    if (HasUserPerm(PERM_ACCOUNTS|PERM_SYSOP) && locmem->crs_ln>0) {
		int             id;
		userec_t        muser;

		strlcpy(currauthor,
			headers[locmem->crs_ln - locmem->top_ln].owner,
			sizeof(currauthor));
		vs_hdr("使用者設定");
		move(1, 0);
		if ((id = getuser(headers[locmem->crs_ln - locmem->top_ln].owner, &muser))) {
		    user_display(&muser, 1);
		    if( HasUserPerm(PERM_ACCOUNTS) )
			uinfo_query(&muser, 1, id);
		    else
			pressanykey();
		}
		mode = FULLUPDATE;
	    }
	    break;

	    /* rocker.011018: 採用新的tag模式 */
	case 't':
	    if(locmem->crs_ln == 0)
		break;
	    /* 將原本在 Read() 裡面的 "TagNum = 0" 移至此處 */
	    if ((currstat & RMAIL && TagBoard != 0) ||
		(!(currstat & RMAIL) && TagBoard != bid)) {
		if (currstat & RMAIL)
		    TagBoard = 0;
		else
		    TagBoard = bid;
		TagNum = 0;
	    }
	    /* rocker.011112: 解決再select mode標記文章的問題 */
	    if (Tagger(atoi(headers[locmem->crs_ln - locmem->top_ln].filename + 2),
		       (currmode & MODE_SELECT) ?
		       (headers[locmem->crs_ln - locmem->top_ln].multi.refer.ref) :
		       locmem->crs_ln, TAG_TOGGLE))
	    {
//		(*doentry) (locmem->crs_ln, &headers[locmem->crs_ln-locmem->top_ln]);
		locmem->crs_ln ++;
		// new_ln = locmem->crs_ln + 1; 
		// new_top = 1;
		// mode = FULLUPDATE;
		// mode = PART_REDRAW;
		mode = PARTUPDATE;
	    }
	    break;

    case Ctrl('C'):
	if (TagNum) {
	    TagNum = 0;
	    mode = FULLUPDATE;
	}
        break;

    case Ctrl('T'):
	/* XXX duplicated code, copy from case 't' */
	if ((currstat & RMAIL && TagBoard != 0) ||
		(!(currstat & RMAIL) && TagBoard != bid)) {
	    if (currstat & RMAIL)
		TagBoard = 0;
	    else
		TagBoard = bid;
	    TagNum = 0;
	}
	mode = TagThread(currdirect);
        break;

    case Ctrl('D'):
	mode = TagPruner(bid);
        break;

    case '\n':
    case '\r':
    case 'l':
    case KEY_RIGHT:
	ch = 'r';
    default:
	if( ch == 'h' && currmode & (MODE_DIGEST) )
	    break;
	if (ch > 0 && ch <= onekey_size) {
	    int (*func)() = rcmdlist[ch - 1].func;
	    if(rcmdlist[ch - 1].needitem && locmem->crs_ln == 0)
		break;
	    if (func != NULL){
		num  = locmem->crs_ln - bottom_line;
                   
		if(!rcmdlist[ch - 1].needitem)
		    mode = (*func)();
		else if( num > 0 ){
		    char    direct[60];
                    sprintf(direct,"%s.bottom", currdirect);
		    mode= (*func)(num, &headers[locmem->crs_ln-locmem->top_ln],
				  direct, locmem->crs_ln - locmem->top_ln);
		}
		else
                    mode = (*func)(locmem->crs_ln, 
				   &headers[locmem->crs_ln - locmem->top_ln],
				   currdirect, locmem->crs_ln - locmem->top_ln);
		if(mode == READ_SKIP)
                    mode = lastmode;

		// 以下這幾種 mode 要再處理游標
                if(mode == READ_PREV || mode == READ_NEXT || 
                   mode == RELATE_PREV || mode == RELATE_FIRST || 
                   mode == AUTHOR_NEXT || mode ==  AUTHOR_PREV ||
                   mode == RELATE_NEXT){
		    lastmode = mode;

		    switch(mode){
                    case READ_PREV:
                        new_ln =  locmem->crs_ln - 1;
                        break;
                    case READ_NEXT:
                        new_ln =  locmem->crs_ln + 1;
                        break;
	            case RELATE_PREV:
                        new_ln = thread(locmem, RELATE_PREV);
			break;
                    case RELATE_NEXT:
                        new_ln = thread(locmem, RELATE_NEXT);
			/* XXX: 讀到最後一篇要跳出來 */
			if( new_ln == locmem->crs_ln ){
			    default_ch = 0;
			    return FULLUPDATE;
			}
		        break;
                    case RELATE_FIRST:
                        new_ln = thread(locmem, RELATE_FIRST);
		        break;
                    case AUTHOR_PREV:
                        new_ln = thread(locmem, AUTHOR_PREV);
		        break;
                    case AUTHOR_NEXT:
                        new_ln = thread(locmem, AUTHOR_NEXT);
		        break;
		    }
		    mode = DONOTHING; default_ch = 'r';
                }
		else {
		    default_ch = 0;
		    lastmode = DONOTHING;
		}
	    } //end if (func != NULL)
	} // ch > 0 && ch <= onekey_size 
    	break;
	} // end switch
    } while (mode == DONOTHING);
    return mode;
}

// recbase:	顯示位置的開頭
// headers_size:要顯示幾行
// last_line:	全板 .DIR + 置底 的有效數目
// bottom_line:	全板 .DIR (無置底) 的有效數目

// XXX never return -1!

static int
get_records_and_bottom(char *direct,  fileheader_t* headers,
                     int recbase, int headers_size, int last_line, int bottom_line)
{
    // n: 置底除外的可顯示數目
    int     n = bottom_line - recbase + 1, rv = 0;

    if( last_line < 1)	// 完全沒東西
	return 0;

    // 不顯示置底的情形
    if( n >= headers_size || (currmode & (MODE_SELECT | MODE_DIGEST)) )
    {
	rv = get_records(direct, headers, sizeof(fileheader_t), 
		recbase, headers_size);
	return rv > 0 ? rv : 0;
    }

    //////// 顯示本文+置底: ////////

    // 讀取 .DIR 本文
    if (n > 0)
    {
	n = get_records(direct, headers, sizeof(fileheader_t), recbase, n);
	if (n < 0) n = 0;
	rv += n; // rv 為有效本文數

	recbase = 1;
    } else {
	// n <= 0
	recbase = 1 + (-n);
    }

    // 讀取置底 (注意 recbase 可能超過 bottom_line, 也就是以置底第 n 個開始)
    n = last_line - bottom_line +1 - (recbase-1);
    if (rv + n > headers_size)
	n = headers_size - rv;

    if (n > 0) {
	char    directbottom[PATHLEN];
	snprintf(directbottom, sizeof(directbottom), "%s.bottom", direct);
	n = get_records(directbottom, headers+rv, sizeof(fileheader_t), recbase, n);
	if (n < 0) n = 0;
	rv += n;
    }

    return rv;
}

void
i_read(int cmdmode, const char *direct, void (*dotitle) (),
       void (*doentry) (), const onekey_t * rcmdlist, int bidcache)
{
    keeploc_t      *locmem = NULL;
    int             recbase = 0, mode;
    int             entries = 0;
    char            currdirect0[PATHLEN];
    int             last_line0 = last_line;
    int             bottom_line = 0;
    fileheader_t   *headers0 = headers;
    int             headers_size0 = headers_size;
    time4_t	    enter_time = now;

    strlcpy(currdirect0, currdirect, sizeof(currdirect0));
#define FHSZ    sizeof(fileheader_t)
    /* Ptt: 這邊 headers 可以針對看板的最後 60 篇做 cache */
    headers_size = p_lines;
    headers = (fileheader_t *) calloc(headers_size, FHSZ);
    assert(headers != NULL);
    strlcpy(currdirect, direct, sizeof(currdirect));
    mode = NEWDIRECT;

    do {
	/* 檢查權限是否已改 */
	if (currbid > 0 && getbcache(currbid)->perm_reload > enter_time)
	{
	    boardheader_t *bp = getbcache(currbid);
	    if(!HasBoardPerm(bp))
		break;
	    enter_time = bp->perm_reload;
	}

	/* 依據 mode 顯示 fileheader */
	setutmpmode(cmdmode);
	switch (mode) {
	case DONOTHING:
	    break;

	case NEWDIRECT:	/* 第一次載入此目錄 */
	case DIRCHANGED:
	    if (bidcache > 0 && !(currmode & (MODE_SELECT | MODE_DIGEST))){
		if( (last_line = getbtotal(currbid)) == 0 ){
		    setbtotal(currbid);
                    setbottomtotal(currbid);
		    last_line = getbtotal(currbid);
		}
                bottom_line = last_line;
                last_line += getbottomtotal(currbid); 
	    }
	    else
		bottom_line = last_line = get_num_records(currdirect, FHSZ);

	    if (mode == NEWDIRECT) {
		int num;
		num = last_line - p_lines + 1;
		locmem = getkeep(currdirect, num < 1 ? 1 : num, 
			bottom_line ? bottom_line : last_line);
		if(newdirect_new_ln >= 0)
		{
		  locmem->crs_ln = newdirect_new_ln + 1;
		  newdirect_new_ln = -1;
		}
	    }
	    recbase = -1;
	    /* no break */

	default: // for any unknown keys
	case FULLUPDATE:
	    (*dotitle) ();
	    /* no break */

	case PARTUPDATE:
	    if (headers_size != p_lines) {
		headers_size = p_lines;
		headers = (fileheader_t *) realloc(headers, headers_size*FHSZ);
		assert(headers);
	    }

	    /* In general, records won't be reloaded in PARTUPDATE state.
	     * But since a board is often changed and cached, it is always
	     * reloaded here. */
	    if (bidcache > 0 && !(currmode & (MODE_SELECT | MODE_DIGEST))) {
		int rec_num;
		bottom_line = getbtotal(currbid);
		rec_num = bottom_line + getbottomtotal(currbid);
		if (last_line != rec_num) {
		    last_line = rec_num;
		    recbase = -1;
		}
	    }

	    if (recbase != locmem->top_ln) { //headers reload
		recbase = locmem->top_ln;
		if (recbase > last_line) {
		    recbase = last_line - headers_size + 1;
		    if (recbase < 1)
			recbase = 1;
		    locmem->top_ln = recbase;
		}
		/* XXX if entries return -1 or black-hole */
                entries = get_records_and_bottom(currdirect,
                           headers, recbase, headers_size, last_line, bottom_line);
	    }
	    if (locmem->crs_ln > last_line)
		locmem->crs_ln = last_line;
	    move(3, 0);
	    clrtobot();
	    /* no break */
	case PART_REDRAW:
	    move(3, 0);
            if( last_line == 0 )
                  outs("    沒有文章...");
            else {
		int i;
		for( i = 0; i < entries ; i++ )
		    (*doentry) (locmem->top_ln + i, &headers[i]);
	    }
	    /* no break */
	case READ_REDRAW:
	    if (curredit & EDIT_MAIL)
		vs_footer(" 鴻雁往返 ",
		       	" (R)回信 (x)站內轉寄 (y)回群組信  (d/D)刪信 (m)保留標記\t(←/q)離開");
	    else
		vs_footer(" 文章選讀 ",
		    " (y)回應(X)推文(x)轉錄 (=[]<>)相關主題(/?a)搜尋標題/作者 (b)進板畫面");
	    break;

	case TITLE_REDRAW:
	    (*dotitle) ();
            break;
        
        case HEADERS_RELOAD:
	    if (recbase != locmem->top_ln) {
		recbase = locmem->top_ln;
		if (recbase > last_line) {
		    recbase = last_line - p_lines + 1;
		    if (recbase < 1)
			recbase = 1;
		    locmem->top_ln = recbase;
		}
		if(headers_size != p_lines) {
		    headers_size = p_lines;
		    headers = (fileheader_t *) realloc(headers, headers_size*FHSZ);
		    assert(headers);
		}
		/* XXX if entries return -1 */
                entries = 
		    get_records_and_bottom(currdirect, headers, recbase,
					   headers_size, last_line, bottom_line);
	    }
            break;
	} //end switch
	mode = i_read_key(rcmdlist, locmem, currbid, bottom_line);
    } while (mode != DOQUIT);
#undef  FHSZ

    free(headers);
    last_line = last_line0;
    headers = headers0;
    headers_size = headers_size0;
    strlcpy(currdirect, currdirect0, sizeof(currdirect));
    return;
}