/* This file is part of
 * ======================================================
 * 
 *          LyX, The Document Processor
 * 	 
 *          Copyright 1995 Matthias Ettrich
 *          Copyright 1995-1999 The LyX Team.
 *
 * ======================================================*/

#include <config.h>
#include <cstring>
#include <cstdio>
#include "support/lstrings.h"
#include "gettext.h"

#ifdef __GNUG__
#pragma implementation
#endif

#include "kbmap.h"
#include "debug.h"

// The only modifiers that we handle. We want to throw away things
// like NumLock. 
enum { ModsMask = ShiftMask | ControlMask | Mod1Mask};


// === static functions ===================================================


/* ---F+------------------------------------------------------------------ *\
   Function  : printKeysym
   Called by : kb_sequence::print and printKeyMap. RVDK_PATCH_5
   Purpose   : prints a keysym, including modifiers.
   Parameters: key    - keysym
               mod    - modifiers
               buf    - string where the result goes
	       maxlen - length of string (including '\0')
   Returns   : length of printed string if ok, 0 otherwise.
\* ---F------------------------------------------------------------------- */

static
int printKeysym( KeySym key, unsigned int mod, char *buf, int maxlen )
{
	int len;
	char *s;
	
	mod &= ModsMask;

	// calc required length;
	len = 0;
	if ( mod & ShiftMask )   len += 2;
	if ( mod & ControlMask ) len += 2;
	if ( mod & Mod1Mask )    len += 2;
	
	s = XKeysymToString( key );
	if ( s ) len += strlen( s );
	if ( len < maxlen ) {
		if ( mod & ShiftMask ) {
			*buf++ = 'S'; *buf++ = '-'; }
		if ( mod & ControlMask ) {
			*buf++ = 'C'; *buf++ = '-'; }
		if ( mod & Mod1Mask ) {
			*buf++ = 'M'; *buf++ = '-'; }
		if ( s ) strcpy( buf, s );
		return len;
	} else 
		return 0;
}


/* ---F+------------------------------------------------------------------ *\
   Function  : printKeyTab
   Called by : kb_keymap::print
   Purpose   : print the keysyms found in the given key table. RVDK_PATCH_5
   Parameters: tabPt  - keytable pointer
               buf    - string where the result goes
               maxLen - length of string (including '\0')
   Returns   : length of printed string.
\* ---F------------------------------------------------------------------- */

static
int printKeyTab( kb_key *tabPt, char *buf, int maxLen )
{
	int len, doneLen = 0;
	unsigned int ksym, mod;
	
	/* -------> Print each of the slots into buf. */
	for( ; (tabPt->code & 0xffff) != NoSymbol; tabPt++) {
		if ( maxLen <= 0 ) break;
		
		ksym =  tabPt->code;
		mod  =  tabPt->mod & 0xffff;
		
		len = printKeysym( ksym, mod, buf, maxLen );
		if ( len <= 0 ) break;
		buf     += len;
		maxLen  -= len;
		doneLen += len;
		
		/* -------> Add space when possible. */
		if ( maxLen > 0 ) {
			*buf++ = ' ';
			*buf = '\0';
			maxLen--;
			doneLen++;
		}
	}
	return doneLen;
}



// === kb_sequence methods ================================================



/* ---F+------------------------------------------------------------------ *\
    Function  : kb_sequence::addkey
    Called by : [user]
    Purpose   : add a key to the sequence, look up in map and return action
    Parameters: key  - keysym of key
                mod  - modifier mask
                nmod - modifier veto mask (unused now)
    Returns   : action or -1 if error (no map defined or key not found)
\* ---F------------------------------------------------------------------- */

int kb_sequence::addkey(KeySym key, unsigned int mod, unsigned int nmod /*=0*/)
{
	if(length<0) length=0;

	if(length+1 >= size) {
		unsigned int *nseq = new unsigned int[size+KB_PREALLOC];
		size += KB_PREALLOC;
		memcpy(nseq, sequence, length*sizeof(unsigned int));
		if(sequence != staticseq) delete sequence;
		sequence = nseq;
		nseq = new unsigned int[size];
		memcpy(nseq, modifiers, length*sizeof(unsigned int));
		if(modifiers != staticmod) delete modifiers;
		modifiers = nseq;
	}

	modifiers[length]  = mod + (nmod<<16);
	sequence[length++] = key;
   
	if(curmap)
		return curmap->lookup(key, mod, this);
	
	return -1;
}


/* ---F+------------------------------------------------------------------ *\
    Function  : kb_sequence::parse
    Called by : [user]
    Purpose   : parse a string that holds a key sequence and add the keys
    Parameters: s - string holding the key sequence
    Returns   : 0 - if ok, error pos if error
    Note      : Keys must be separated with whitespace;
                Use the keysym names used by XStringToKeysym
                Prefixes are S-, C-, M- for shift, control, meta
\* ---F------------------------------------------------------------------- */

int kb_sequence::parse(char const*s)
{
	int i = 0;
	unsigned int mod = 0, nmod = 0;
	KeySym key = 0;
	char tbuf[100];
	
	if(!s[0]) return 1;
	
	while(s[i]) {
		if(s[i] && (s[i]) <= ' ') i++;
		if(!s[i]) break;
		
		if(s[i+1]=='-')	{ // is implicit that s[i]==true
			switch(s[i]) {
			case 's': case 'S':
				mod |= ShiftMask;
				i+=2;
				continue;
			case 'c': case 'C':
				mod |= ControlMask;
				i+=2;
				continue;
			case 'm': case 'M':
				mod |= Mod1Mask;
				i+=2;
				continue;
			default:
				return i+1;
			}
		} else if(s[i]=='~' && s[i+1] && s[i+2]=='-') {
			switch(s[i+1]) {
			case 's': case 'S':
				nmod |= ShiftMask;
				i+=3;
				continue;
			case 'c': case 'C':
				nmod |= ControlMask;
				i+=3;
				continue;
			case 'm': case 'M':
				nmod |= Mod1Mask;
				i+=3;
				continue;
			default:
				return i+2;
			}
		} else {
			int j = 0;
			for(j = i; s[j] && (s[j])>' '; j++)
				tbuf[j-i] = s[j];    // (!!!check bounds :-)
			
			tbuf[j-i] = '\0';
         
			key = XStringToKeysym(tbuf);
			if(key == NoSymbol) {
				lyxerr[Debug::KBMAP]
					<< "kbmap.C: No such keysym: "
					<< tbuf << endl;
				return j;
			}
			i = j;
			
			addkey(key, mod, nmod);
			mod = 0;
			nmod = 0;
		}
	}
	return 0;
}


/* ---F+------------------------------------------------------------------ *\
    Function  : kb_sequence::print
    Called by : [user]
    Purpose   : print the currently defined sequence into a string
    Parameters: buf           - string where the result goes
                maxlen        - length of string (including '\0')
                when_defined  - only  print when sequence is real: length > 0.
    Returns   : 0, if ok, -1 if string too long
\* ---F------------------------------------------------------------------- */

int kb_sequence::print(char *buf, int maxlen, bool when_defined) const
{
	KeySym key;
	unsigned int mod;
	int len;
	int l = length;
	if ( l<0 && !when_defined ) l = -l;
	
	for(int i = 0; i < l; i++) {
		key = sequence[i];
		mod = modifiers[i] & 0xffff;

		len = printKeysym( key, mod, buf, maxlen );  // RVDK_PATCH_5
		buf += len;
		maxlen -= len;
		
		if ( len == 0 ) {
			*buf = '\0';
			return -1;
		}

		if(i+1<l && maxlen>1) {  // append a blank
			*buf++ = ' ';
			maxlen--;
		}
	}
	*buf = '\0';
	return 0;
}


/* ---F+------------------------------------------------------------------ *\
    Function  : kb_sequence::printOptions
    Called by : [user]
    Purpose   : print the available key options from the current state in the
                sequence. RVDK_PATCH_5
    Parameters: buf    - string where the result goes
                maxlen - length of string (including '\0')
    Returns   : 0, if ok, -1 if string too long
\* ---F------------------------------------------------------------------- */

int kb_sequence::printOptions(char *buf, int maxlen) const
{
	int len;

	print( buf, maxlen, true );
	len = strlen( buf );
	maxlen -= len;
	buf    += len;
	
	if ( maxlen < 20 || !curmap ) return -1;
#ifdef WITH_WARNINGS
#warning reimplement kb_sequence using string
#endif
	char s[20];
	strcpy(s,_("   options: "));
	strcpy( buf, s);
	buf += strlen(s);
	maxlen -= strlen(s);

	curmap->print(buf, maxlen);
	return 0;
}


/* ---F+------------------------------------------------------------------ *\
    Function  : kb_sequence::delseq
    Called by : [user]
    Purpose   : mark the sequence as deleted
    Parameters: none
    Returns   : nothing
\* ---F------------------------------------------------------------------- */

void kb_sequence::delseq()
{
	// negative length marks sequence as deleted, but we can still
	// print() it or retrieve the last char using getiso()
	length = -length;
}


/* ---F+------------------------------------------------------------------ *\
   Function  : kb_sequence::getsym
   Called by : [user], getiso
   Purpose   : get the keysym of the last key in sequence
   Parameters: none
   Returns   : keysym
\* ---F------------------------------------------------------------------- */

KeySym kb_sequence::getsym()
{
	int l = length;
	if(l==0) return NoSymbol;
	if(l<0) l = -l;
	return sequence[l-1];
}


/* ---F+------------------------------------------------------------------ *\
    Function  : kb_sequence::getiso
    Called by : [user]
    Purpose   : return iso character code of last key, if any
    Parameters: none
    Returns   : iso code or 0 if none
\* ---F------------------------------------------------------------------- */

char kb_sequence::getiso()
{
	int c = getsym();
	
	if(c > 0xff)
		return '\0';
	return (char)c;
}


/* ---F+------------------------------------------------------------------ *\
    Function  : kb_sequence::reset
    Called by : [user]
    Purpose   : reset sequence to initial state. RVDK_PATCH_5
    Parameters: none
    Returns   : void
\* ---F------------------------------------------------------------------- */

void kb_sequence::reset()
{
	delseq();
	curmap = stdmap;
	if ( length > 0 ) length = -length;
}


// === kb_keymap methods ==================================================

// This binds a key to an action
int kb_keymap::bind(char const *seq, int action)
{
	kb_sequence k;

	int res = k.parse(seq);
	if (!res) {
		defkey(&k, action);
	} else
		lyxerr[Debug::KBMAP] << "Parse error at position " << res
				     << " in key sequence '" << seq << "'."
				     << endl;
	return res;
}


/* ---F+------------------------------------------------------------------ *\
    Function  : kb_keymap::lookup
    Called by : [user], kb_sequence::add()
    Purpose   : look up a key press in a given keymap
    Parameters: key - the keysym of the key press
                mod - the modifier mask of the keypress
                seq - the key-sequence retrieved so far
    Returns   : user defined action; 0 for prefix key, -1 if key not found
\* ---F------------------------------------------------------------------- */

int kb_keymap::lookup(KeySym key, unsigned int mod, kb_sequence *seq)
{
	unsigned int hashval, ksym, msk1, msk0;
	kb_key *tab;

	//suppress modifier bits we do not handle
	mod &= ModsMask;

	if(!table) {
		// error - no keymap defined:
		seq->curmap = seq->stdmap;
		seq->delseq();
		return -1;
	}

	if(size < 0) {               // --- if hash table ---
		hashval = ((key&0xff) ^ ((key>>8)&0xff)) % KB_HASHSIZE;
		tab = htable[hashval];
		if(!tab) {
			seq->curmap = seq->stdmap;
			seq->delseq();
			return -1;
		}
	} else                       // --- else: linear list ---
		tab = table;

	// --- now search the list of keys ---

	for( ; (tab->code & 0xffff) != NoSymbol; tab++) {
		ksym =  tab->code;
		msk1 =  tab->mod      & 0xffff;
		msk0 = (tab->mod>>16) & 0xffff;

		if(ksym == key && (mod&~msk0) == msk1) {
			// match found:
			if(tab->table) {
				 // this is a prefix key - set new map
				seq->curmap = tab->table;
				return 0;
			} else {
				  // final key - reset map
				seq->curmap = seq->stdmap;
				seq->delseq();
				return tab->action; // ... and return action
			}
		}
	}
	
	// error - key not found:
	seq->curmap = seq->stdmap;
	seq->delseq();
	return -1;
}


/* ---F+------------------------------------------------------------------ *\
    Function  : kb_keymap::print
    Called by : [user]
    Purpose   : Prints all the available keysyms. RVDK_PATCH_5
    Parameters: buf    - string where output goes.
               maxLen - available length in string, including `\0'.
    Returns   : updated maxLen.
\* ---F------------------------------------------------------------------- */

int kb_keymap::print(char *buf, int maxLen) const
{
	int                    len;
	
 /* -----> Return when running out of string space or when keymap has no table.
     Else, place a terminating newline in case no other output is generated. */

	if ( maxLen <= 3 || !buf ) return maxLen;
	if ( !table ) return maxLen;
	*buf   = '\0';
   
 /* -------> Hash table. Process each of its slots recursively and return. */
	if ( size < 0 ) {   
		for ( int ix = 0; (ix < KB_HASHSIZE) && (maxLen > 1); ix++ ) {
			if ( htable[ix] ) {
				len = printKeyTab( htable[ix], buf, maxLen );
				maxLen -= len;
				buf    += len;
			}
		}
	} else {
		/* -------> Normal table. */
		len = printKeyTab( table, buf, maxLen ); 
		maxLen -= len;
		buf    += len;
	}
	return maxLen;
}


/* ---F+------------------------------------------------------------------ *\
    Function  : kb_keymap::defkey
    Called by : [user]
    Purpose   : define an action for a key sequence
    Parameters: seq    - the key sequence
                action - the action to be defined
                idx    - recursion depth
    Returns   : 0 if ok.
\* ---F------------------------------------------------------------------- */

int kb_keymap::defkey(kb_sequence *seq, int action, int idx /*=0*/)
{
	int      tsize;
	unsigned int code, modmsk;
	kb_key  *tab, **ptab;

	code = seq->sequence[idx];
	modmsk = seq->modifiers[idx];
	if(code == NoSymbol) return -1;

	// --- get list------------------------------------------------------
	if(!table) {
		// If we don't have any yet, make an empty one
		table = new kb_key[KB_PREALLOC];
		table[0].code = NoSymbol;
		tab   =  table;
		ptab  = &table;
		size  = KB_PREALLOC;
	} else if(size<0) {
		// Hash table.
		int hashval = (code&0xffff);
		hashval = ((hashval&0xff) ^ ((hashval>>8)&0xff)) % KB_HASHSIZE;
		tab  = htable[hashval];
		ptab = htable+hashval;
		if(!tab) {
			tab = new kb_key[KB_PREALLOC];
			tab[0].code = NoSymbol;
			*ptab = tab;
		}
	} else {
		tab  =  table;
		ptab = &table;
	}

	// --- check if key is already there --------------------------------

	kb_key *t;
	for(t = tab, tsize=1; t->code != NoSymbol; t++, tsize++) {
		if(code == t->code && modmsk == t->mod) { // -- overwrite binding ---
			if(idx+1 == seq->length) {
				char buf[20]; buf[0] = 0;
				seq->print(buf, 20, true);
				lyxerr[Debug::KEY]
					<< "Warning: New binding for '"
					<< buf 
					<< "' is overriding old binding..."
					<< endl;

				if(t->table) {
					delete t->table;
					t->table = 0;
				}
				t->action = action;
				return 0;
			} else if (!t->table) {
				char buf[20]; buf[0] = 0;
				seq->print(buf, 20, true);
				lyxerr << "Error: New binding for '" << buf
				       << "' is overriding old binding..."
				       << endl;
				return -1;
			} else
				return t->table->defkey(seq, action, idx+1);
		}
	}

	// --- extend list if necessary -------------------------------------

	if(tsize % KB_PREALLOC == 0) {
		kb_key *nt = new kb_key[tsize+KB_PREALLOC];
		// Set to 0 as table is used uninitialised later (thornley)
		nt[tsize].table = 0;
		memcpy(nt, tab, tsize*sizeof(kb_key));
		*ptab = nt;
		delete[] tab;
		tab = nt;
		if(size>=0) size = tsize+KB_PREALLOC;
	}

	// --- add action ---------------------------------------------------

	tab[tsize--].code = NoSymbol;
	tab[tsize].code = code;
	tab[tsize].mod  = modmsk;
	kb_key *newone = &tab[tsize];
	
	// --- convert list to hash table if necessary ----------------------

	if(size>=0 && tsize>=32) {
		kb_key *oldtab = tab;
		kb_key **nht = new kb_key*[KB_HASHSIZE];
		for(int i = 0; i < KB_HASHSIZE; i++)
			nht[i] = 0;
		htable = nht;
		size   = -KB_HASHSIZE;
		
		// --- copy old keys to new hash table ---
		int hashval;
		for(kb_key *tu = oldtab; tu->code != NoSymbol; tu++){
			// copy values from oldtab to htable
			hashval = (tu->code&0xffff);
			hashval = ((hashval&0xff) ^ ((hashval>>8)&0xff)) % KB_HASHSIZE;
			tab  = htable[hashval];
			
			if(!tab){
				htable[hashval] = tab = new kb_key[KB_PREALLOC];
				tab->code = NoSymbol;
			}
			int ts = 1;
			for(kb_key *tt = tab; tt->code != NoSymbol; tt++)
				ts++;
			if(ts % KB_PREALLOC == 0){
				// extend table
				kb_key *nt = new kb_key[ts+KB_PREALLOC];
				memcpy(nt, tab, ts*sizeof(kb_key));
				htable[hashval] = nt;
				delete[] tab;
				tab = nt;
			}
			tab[ts--].code = NoSymbol;
			tab[ts].code   = tu->code;
			tab[ts].mod    = tu->mod;
			tab[ts].action = tu->action;
			tab[ts].table  = tu->table;
			
			if(tu == newone)
				newone = &tab[ts];
		}
		delete[] oldtab;
	}
	
	// --- define rest of sequence --------------------------------------

	if(idx+1 == seq->length) {
		newone->action = action;
		newone->table  = 0;
		return 0;
	} else {
		newone->table = new kb_keymap;
		int res = newone->table->defkey(seq, action, idx+1);
		return res;
	}
}


/* ---F+------------------------------------------------------------------ *\
    Function  : kb_keymap::~kb_keymap
    Called by : [destructor]
    Purpose   : free keymap and its descendents
    Parameters: none
    Returns   : nothing
\* ---F------------------------------------------------------------------- */

kb_keymap::~kb_keymap()
{
	if(!table) return;
	if(size<0) {
		for(int i=0; i < KB_HASHSIZE; i++) {
			if(htable[i]) {
				for(kb_key *t = htable[i]; t->code != NoSymbol; t++)
					if(t->table)
						delete t->table;
				delete htable[i];
			}
		}
		delete htable;
	} else {
		for(kb_key *t = table; t->code != NoSymbol; t++)
			if(t->table)
				delete t->table;
		delete table;
	}
}

string keyname(kb_key k) {
	char buf[100];
	printKeysym(k.code, k.mod, buf, 100);
	return buf;
}

// Finds a key for a keyaction, if possible
string kb_keymap::findbinding(int act) const {
	string res;
	if (!table)
		return res;

	if (size<0) {
		for(int i=0; i < KB_HASHSIZE; i++) {
			if(htable[i]) {
				for(kb_key *t = htable[i]; t->code != NoSymbol; t++) {
					if(t->table) {
						string suffix = t->table->findbinding(act);
						suffix = strip(suffix, ' ');
						suffix = strip(suffix, ']');
						suffix = frontStrip(suffix, '[');
						if (!suffix.empty()) {
							res += "[" + keyname(*t) + " " + suffix + "] ";
						}
					} else if (t->action == act) {
						res += "[" + keyname(*t) + "] ";
					}
				}
			}
		}
	} else {
		for(kb_key *t = table; t->code != NoSymbol; t++) {
			if(t->table) {
				string suffix = t->table->findbinding(act);
				suffix = strip(suffix, ' ');
				suffix = strip(suffix, ']');
				suffix = frontStrip(suffix, '[');
				if (!suffix.empty()) {
					res += "[" + keyname(*t) + " " + suffix + "] ";
				}
			} else if (t->action == act) {
				res += "[" + keyname(*t) + "] ";
			}
		}
	}
	return res;
}


/* === End of File: kbmap.C ============================================== */