/************************************************

  tkutil.c -

  $Author$
  $Date$
  created at: Fri Nov  3 00:47:54 JST 1995

************************************************/

#include "ruby.h"
#include "st.h"

static VALUE cMethod;

static VALUE cTclTkLib;

static VALUE cTkObject;
static VALUE cTkCallbackEntry;

static VALUE TK_None;

static VALUE cCB_SUBST;
static VALUE cSUBST_INFO;

static ID ID_split_tklist;
static ID ID_toUTF8;
static ID ID_fromUTF8;
static ID ID_path;
static ID ID_at_path;
static ID ID_to_eval;
static ID ID_to_s;
static ID ID_install_cmd;
static ID ID_merge_tklist;
static ID ID_call;

static ID ID_SUBST_INFO;

static VALUE CALLBACK_TABLE;
static unsigned long CALLBACK_ID_NUM = 0;

/*************************************/

static VALUE
tk_s_new(argc, argv, klass)
    int argc;
    VALUE *argv;
    VALUE klass;
{
    VALUE obj = rb_class_new_instance(argc, argv, klass);

    if (rb_block_given_p()) rb_obj_instance_eval(0, 0, obj);
    return obj;
}

/*************************************/

static VALUE
tkNone_to_s(self)
    VALUE self;
{
    return rb_str_new2("None");
}

/*************************************/

static VALUE
tk_eval_cmd(argc, argv, self)
    int argc;
    VALUE argv[];
    VALUE self;
{
    volatile VALUE cmd, rest, arg;
    volatile VALUE ret;
    int status;

    rb_scan_args(argc, argv, "1*", &cmd, &rest);
    return rb_eval_cmd(cmd, rest, 0);
}

static VALUE
tk_do_callback(argc, argv, self)
    int   argc;
    VALUE *argv;
    VALUE self;
{
#if 0
    volatile VALUE id;
    volatile VALUE rest;

    rb_scan_args(argc, argv, "1*", &id, &rest);
    return rb_apply(rb_hash_aref(CALLBACK_TABLE, id), ID_call, rest);
#endif
    return rb_funcall2(rb_hash_aref(CALLBACK_TABLE, argv[0]), 
		       ID_call, argc - 1, argv + 1);
}

static char *cmd_id_head = "ruby_cmd TkUtil callback ";
static char *cmd_id_prefix = "cmd";

static VALUE
tk_install_cmd_core(cmd)
    VALUE cmd;
{
    volatile VALUE id_num;

    id_num = ULONG2NUM(CALLBACK_ID_NUM++);
    id_num = rb_funcall(id_num, ID_to_s, 0, 0);
    id_num = rb_str_append(rb_str_new2(cmd_id_prefix), id_num);
    rb_hash_aset(CALLBACK_TABLE, id_num, cmd);
    return rb_str_append(rb_str_new2(cmd_id_head), id_num);
}

static VALUE
tk_install_cmd(argc, argv, self)
    int   argc;
    VALUE *argv;
    VALUE self;
{
    volatile VALUE cmd;

#if 0
    if (rb_scan_args(argc, argv, "01", &cmd) == 0) {
	cmd = rb_block_proc();
    }
    return tk_install_cmd_core(cmd);
#endif
    if (argc == 0) {
	cmd = rb_block_proc();
    } else {
	cmd = argv[0];
    }
    return tk_install_cmd_core(cmd);
}

static VALUE
tk_uninstall_cmd(self, cmd_id)
    VALUE self;
    VALUE cmd_id;
{
    int head_len = strlen(cmd_id_head);
    int prefix_len = strlen(cmd_id_prefix);

    StringValue(cmd_id);
    if (strncmp(cmd_id_head, RSTRING(cmd_id)->ptr, head_len) != 0) {
	return Qnil;
    }
    if (strncmp(cmd_id_prefix, 
		RSTRING(cmd_id)->ptr + head_len, prefix_len) != 0) {
	return Qnil;
    }

    return rb_hash_delete(CALLBACK_TABLE, 
			  rb_str_new2(RSTRING(cmd_id)->ptr + head_len));
}

static VALUE
tk_toUTF8(argc, argv, self)
    int   argc;
    VALUE *argv;
    VALUE self;
{
    return rb_funcall2(cTclTkLib, ID_toUTF8, argc, argv);
}

static VALUE
tk_fromUTF8(argc, argv, self)
    int   argc;
    VALUE *argv;
    VALUE self;
{
    return rb_funcall2(cTclTkLib, ID_fromUTF8, argc, argv);
}

static VALUE
fromDefaultEnc_toUTF8(str, self)
    VALUE str;
    VALUE self;
{
    VALUE argv[1];

    argv[0] = str;
    return tk_toUTF8(1, argv, self);
}

static VALUE
fromUTF8_toDefaultEnc(str, self)
    VALUE str;
    VALUE self;
{
    VALUE argv[1];

    argv[0] = str;
    return tk_fromUTF8(1, argv, self);
}


static int
to_strkey(key, value, hash)
    VALUE key;
    VALUE value;
    VALUE hash;
{
    if (key == Qundef) return ST_CONTINUE;
    rb_hash_aset(hash, rb_funcall(key, ID_to_s, 0, 0), value);
    return ST_CONTINUE;
}

static VALUE
tk_symbolkey2str(self, keys)
    VALUE self;
    VALUE keys;
{
    volatile VALUE new_keys = rb_hash_new();

    st_foreach(RHASH(keys)->tbl, to_strkey, new_keys);
    return new_keys;
}

static VALUE get_eval_string_core _((VALUE, VALUE, VALUE));
static VALUE ary2list _((VALUE, VALUE));
static VALUE hash2list _((VALUE, VALUE));

static VALUE
ary2list(ary, self)
    VALUE ary;
    VALUE self;
{
    int idx, size;
    volatile VALUE val;
    volatile VALUE dst;

    size = RARRAY(ary)->len;
    dst = rb_ary_new2(size);
    RARRAY(dst)->len = 0;
    for(idx = 0; idx < size; idx++) {
	val = RARRAY(ary)->ptr[idx];
	switch(TYPE(val)) {
	case T_ARRAY:
	    RARRAY(dst)->ptr[RARRAY(dst)->len++] = ary2list(val, self);
	    break;

	case T_HASH:
	    RARRAY(dst)->ptr[RARRAY(dst)->len++] = hash2list(val, self);
	    break;

	default:
	    if (val != TK_None) {
		RARRAY(dst)->ptr[RARRAY(dst)->len++] 
		    = get_eval_string_core(val, Qnil, self);
	    }
	}
    }
    return rb_apply(cTclTkLib, ID_merge_tklist, dst);
}

static VALUE
key2keyname(key)
    VALUE key;
{
    return rb_str_append(rb_str_new2("-"), rb_funcall(key, ID_to_s, 0, 0));
}

static VALUE
assoc2kv(assoc, ary, self)
    VALUE assoc;
    VALUE ary;
    VALUE self;
{
    int i, j, len;
    volatile VALUE pair;
    volatile VALUE val;
    volatile VALUE dst = rb_ary_new2(2 * RARRAY(assoc)->len);

    len = RARRAY(assoc)->len;

    for(i = 0; i < len; i++) {
	pair = RARRAY(assoc)->ptr[i];
	if (TYPE(pair) != T_ARRAY) {
	    RARRAY(dst)->ptr[RARRAY(dst)->len++] = key2keyname(pair);
	    continue;
	}
	switch(RARRAY(assoc)->len) {
	case 2:
	    RARRAY(dst)->ptr[RARRAY(dst)->len++] = RARRAY(pair)->ptr[2];

	case 1:
	    RARRAY(dst)->ptr[RARRAY(dst)->len++] 
		= key2keyname(RARRAY(pair)->ptr[0]);

	case 0:
	    continue;

	default:
	    RARRAY(dst)->ptr[RARRAY(dst)->len++] 
		= key2keyname(RARRAY(pair)->ptr[0]);

	    val = rb_ary_new2(RARRAY(pair)->len - 1);
	    RARRAY(val)->len = 0;
	    for(j = 1; j < RARRAY(pair)->len; j++) {
		RARRAY(val)->ptr[RARRAY(val)->len++] = RARRAY(pair)->ptr[j];
	    }

	    RARRAY(dst)->ptr[RARRAY(dst)->len++] = val;
	}
    }

    if (NIL_P(ary)) {
	return dst;
    } else {
	return rb_ary_plus(ary, dst);
    }
}

static VALUE
assoc2kv_enc(assoc, ary, self)
    VALUE assoc;
    VALUE ary;
    VALUE self;
{
    int i, j, len;
    volatile VALUE pair;
    volatile VALUE val;
    volatile VALUE dst = rb_ary_new2(2 * RARRAY(assoc)->len);

    len = RARRAY(assoc)->len;

    for(i = 0; i < len; i++) {
	pair = RARRAY(assoc)->ptr[i];
	if (TYPE(pair) != T_ARRAY) {
	    RARRAY(dst)->ptr[RARRAY(dst)->len++] = key2keyname(pair);
	    continue;
	}
	switch(RARRAY(assoc)->len) {
	case 2:
	    RARRAY(dst)->ptr[RARRAY(dst)->len++] 
		= get_eval_string_core(RARRAY(pair)->ptr[2], Qtrue, self);

	case 1:
	    RARRAY(dst)->ptr[RARRAY(dst)->len++] 
		= key2keyname(RARRAY(pair)->ptr[0]);

	case 0:
	    continue;

	default:
	    RARRAY(dst)->ptr[RARRAY(dst)->len++] 
		= key2keyname(RARRAY(pair)->ptr[0]);

	    val = rb_ary_new2(RARRAY(pair)->len - 1);
	    RARRAY(val)->len = 0;
	    for(j = 1; j < RARRAY(pair)->len; j++) {
		RARRAY(val)->ptr[RARRAY(val)->len++] = RARRAY(pair)->ptr[j];
	    }

	    RARRAY(dst)->ptr[RARRAY(dst)->len++] 
		= get_eval_string_core(val, Qtrue, self);
	}
    }

    if (NIL_P(ary)) {
	return dst;
    } else {
	return rb_ary_plus(ary, dst);
    }
}

static int
push_kv(key, val, ary)
    VALUE key;
    VALUE val;
    VALUE ary;
{
    if (key == Qundef) return ST_CONTINUE;
#if 0
    rb_ary_push(ary, key2keyname(key));
    if (val != TK_None) rb_ary_push(ary, val);
#endif
    RARRAY(ary)->ptr[RARRAY(ary)->len++] = key2keyname(key);
    if (val != TK_None) RARRAY(ary)->ptr[RARRAY(ary)->len++] = val;

    return ST_CONTINUE;
}

static VALUE
hash2kv(hash, ary, self)
    VALUE hash;
    VALUE ary;
    VALUE self;
{
    volatile VALUE dst = rb_ary_new2(2 * RHASH(hash)->tbl->num_entries);

    RARRAY(dst)->len = 0;

    st_foreach(RHASH(hash)->tbl, push_kv, dst);

    if (NIL_P(ary)) {
	return dst;
    } else {
	return rb_ary_plus(ary, dst);
    }
}

static int
push_kv_enc(key, val, args)
    VALUE key;
    VALUE val;
    VALUE args;
{
    volatile VALUE ary = RARRAY(args)->ptr[0];

    if (key == Qundef) return ST_CONTINUE;
#if 0
    rb_ary_push(ary, key2keyname(key));
    if (val != TK_None) {
	rb_ary_push(ary, get_eval_string_core(val, Qtrue, 
					      RARRAY(args)->ptr[1]));
    }
#endif
    RARRAY(ary)->ptr[RARRAY(ary)->len++] = key2keyname(key);

    if (val == TK_None) return ST_CONTINUE;

    RARRAY(ary)->ptr[RARRAY(ary)->len++] 
	= get_eval_string_core(val, Qtrue, RARRAY(args)->ptr[1]);

    return ST_CONTINUE;
}

static VALUE
hash2kv_enc(hash, ary, self)
    VALUE hash;
    VALUE ary;
    VALUE self;
{
    volatile VALUE args = rb_ary_new2(2);
    volatile VALUE dst = rb_ary_new2(2 * RHASH(hash)->tbl->num_entries);

    RARRAY(dst)->len = 0;

    RARRAY(args)->ptr[0] = dst;
    RARRAY(args)->ptr[1] = self;
    RARRAY(args)->len = 2;
    st_foreach(RHASH(hash)->tbl, push_kv_enc, args);

    if (NIL_P(ary)) {
	return dst;
    } else {
	return rb_ary_plus(ary, dst);
    }
}

static VALUE
hash2list(hash, self)
    VALUE hash;
    VALUE self;
{
    return ary2list(hash2kv(hash, Qnil, self), self);
}


static VALUE
hash2list_enc(hash, self)
    VALUE hash;
    VALUE self;
{
    return ary2list(hash2kv_enc(hash, Qnil, self), self);
}

static VALUE
tk_hash_kv(argc, argv, self)
    int   argc;
    VALUE *argv;
    VALUE self;
{
    volatile VALUE hash, enc_flag, ary;

    ary = Qnil;
    enc_flag = Qnil;
    switch(argc) {
    case 3:
	ary = argv[2];
    case 2:
	enc_flag = argv[1];
    case 1:
	hash = argv[0];
	break;
    case 0:
	rb_raise(rb_eArgError, "too few arguments");
    default: /* >= 3 */
	rb_raise(rb_eArgError, "too many arguments");
    }

    switch(TYPE(hash)) {
    case T_ARRAY:
	if (RTEST(enc_flag)) {
	    return assoc2kv_enc(hash, ary, self);
	} else {
	    return assoc2kv(hash, ary, self);
	}

    case T_HASH:
	if (RTEST(enc_flag)) {
	    return hash2kv_enc(hash, ary, self);
	} else {
	    return hash2kv(hash, ary, self);
	}

    case T_NIL:
	if (NIL_P(ary)) {
	    return rb_ary_new();
	} else {
	    return ary;
	}

    default:
	if (hash == TK_None) {
	    if (NIL_P(ary)) {
		return rb_ary_new();
	    } else {
		return ary;
	    }
	}
	rb_raise(rb_eArgError, "Hash is expected for 1st argument");
    }
}

static VALUE
get_eval_string_core(obj, enc_flag, self)
    VALUE obj;
    VALUE enc_flag;
    VALUE self;
{
    switch(TYPE(obj)) {
    case T_FLOAT:
    case T_FIXNUM:
    case T_BIGNUM:
	return rb_funcall(obj, ID_to_s, 0, 0);

    case T_STRING:
	if (RTEST(enc_flag)) {
	    if (rb_respond_to(self, ID_toUTF8)) {
		return rb_funcall(self, ID_toUTF8, 1, obj);
	    } else {
		return fromDefaultEnc_toUTF8(obj, self);
	    }
	} else {
	    return obj;
	}

    case T_SYMBOL:
	if (RTEST(enc_flag)) {
	    if (rb_respond_to(self, ID_toUTF8)) {
		return rb_funcall(self, ID_toUTF8, 1, 
				  rb_str_new2(rb_id2name(SYM2ID(obj))));
	    } else {
		return fromDefaultEnc_toUTF8(rb_str_new2(rb_id2name(SYM2ID(obj))), self);
	    }
	} else {
	    return rb_str_new2(rb_id2name(SYM2ID(obj)));
	}

    case T_HASH:
	if (RTEST(enc_flag)) {
	    return hash2list_enc(obj, self);
	} else {
	    return hash2list(obj, self);
	}

    case T_ARRAY:
	if (RTEST(enc_flag)) {
	    return fromDefaultEnc_toUTF8(ary2list(obj, self), self);
	} else {
	    return ary2list(obj, self);
	}

    case T_FALSE:
	return rb_str_new2("0");

    case T_TRUE:
	return rb_str_new2("1");

    case T_NIL:
	return rb_str_new2("");

    default:
	if (rb_obj_is_kind_of(obj, cTkObject)) {
	    /* return rb_str_new3(rb_funcall(obj, ID_path, 0, 0)); */
	    return get_eval_string_core(rb_funcall(obj, ID_path, 0, 0), 
					enc_flag, self);
	}

	if (rb_obj_is_kind_of(obj, rb_cProc)
	    || rb_obj_is_kind_of(obj, cMethod)
	    || rb_obj_is_kind_of(obj, cTkCallbackEntry)) {
	    if (rb_respond_to(self, ID_install_cmd)) {
		return rb_funcall(self, ID_install_cmd, 1, obj);
	    } else {
		return tk_install_cmd_core(obj);
	    }
	}

	if (obj == TK_None)  return Qnil;

	if (rb_respond_to(obj, ID_to_eval)) {
	    /* return rb_funcall(obj, ID_to_eval, 0, 0); */
	    return get_eval_string_core(rb_funcall(obj, ID_to_eval, 0, 0), 
					enc_flag, self);
	} else if (rb_respond_to(obj, ID_path)) {
	    /* return rb_funcall(obj, ID_path, 0, 0); */
	    return get_eval_string_core(rb_funcall(obj, ID_path, 0, 0), 
					enc_flag, self);
	} else if (rb_respond_to(obj, ID_to_s)) {
	    return rb_funcall(obj, ID_to_s, 0, 0);
	}
    }

    rb_warning("fail to convert '%s' to string for Tk", 
	       RSTRING(rb_funcall(obj, rb_intern("inspect"), 0, 0))->ptr);

    return obj;
}

static VALUE
tk_get_eval_string(argc, argv, self)
    int   argc;
    VALUE *argv;
    VALUE self;
{
    volatile VALUE obj, enc_flag;

    if (rb_scan_args(argc, argv, "11", &obj, &enc_flag) == 1) {
	enc_flag = Qnil;
    }

    return get_eval_string_core(obj, enc_flag, self);
}

static VALUE
tk_get_eval_enc_str(self, obj)
    VALUE self;
    VALUE obj;
{
    if (obj == TK_None) {
	return obj;
    } else {
	return get_eval_string_core(obj, Qtrue, self);
    }
}

static VALUE
tk_conv_args(argc, argv, self)
    int   argc;
    VALUE *argv;
    VALUE self;
{
    int idx;
    volatile VALUE dst;
    volatile VALUE head, enc_flag, rest;

    if (argc < 2) {
      rb_raise(rb_eArgError, "too few arguments");
    }
    dst = rb_ary_new2(argc - 2);
    RARRAY(dst)->len = 0;
    for(idx = 2; idx < argc; idx++) {
	if (argv[idx] != TK_None) {
	    RARRAY(dst)->ptr[RARRAY(dst)->len++] 
		= get_eval_string_core(argv[idx], argv[1], self);
	}
    }

    return rb_ary_plus(argv[0], dst);
}


/*************************************/

static VALUE
tcl2rb_bool(self, value)
    VALUE self;
    VALUE value;
{
    if (TYPE(value) == T_FIXNUM) {
	if (NUM2INT(value) == 0) {
	    return Qfalse;
	} else {
	    return Qtrue;
	}
    }

    rb_check_type(value, T_STRING);

    if (RSTRING(value)->ptr[0] == '\0'
	|| strcmp(RSTRING(value)->ptr, "0") == 0
	|| strcmp(RSTRING(value)->ptr, "no") == 0
	|| strcmp(RSTRING(value)->ptr, "false") == 0) {
	return Qfalse;
    } else {
	return Qtrue;
    }
}

static VALUE
tkstr_to_dec(value)
    VALUE value;
{
    return rb_cstr_to_inum(RSTRING(value)->ptr, 10, 1);
}

static VALUE
tkstr_to_int(value)
    VALUE value;
{
    return rb_cstr_to_inum(RSTRING(value)->ptr, 0, 1);
}

static VALUE
tkstr_to_float(value)
    VALUE value;
{
    return rb_float_new(rb_cstr_to_dbl(RSTRING(value)->ptr, 1));
}

static VALUE
tkstr_invalid_numstr(value)
    VALUE value;
{
    rb_raise(rb_eArgError, 
	     "invalid value for Number: '%s'", RSTRING(value)->ptr);
    return Qnil; /*dummy*/
}

static VALUE
tkstr_rescue_float(value)
    VALUE value;
{
    return rb_rescue2(tkstr_to_float, value, 
		      tkstr_invalid_numstr, value, 
		      rb_eArgError, 0);
}

static VALUE
tkstr_to_number(value)
    VALUE value;
{
    rb_check_type(value, T_STRING);

    return rb_rescue2(tkstr_to_int, value, 
		      tkstr_rescue_float, value, 
		      rb_eArgError, 0);
}

static VALUE
tcl2rb_number(self, value)
    VALUE self;
    VALUE value;
{
    return tkstr_to_number(value);
}

static VALUE
tkstr_to_str(value)
    VALUE value;
{
    char * ptr;
    int len;

    ptr = RSTRING(value)->ptr;
    len = RSTRING(value)->len;

    if (len > 1 && *ptr == '{' && *(ptr + len - 1) == '}') {
	return rb_str_new(ptr + 1, len - 2);
    }
    return value;
}

static VALUE
tcl2rb_string(self, value)
    VALUE self;
    VALUE value;
{
    rb_check_type(value, T_STRING);

    return tkstr_to_str(value);
}

static VALUE
tcl2rb_num_or_str(self, value)
    VALUE self;
    VALUE value;
{
    rb_check_type(value, T_STRING);

    return rb_rescue2(tkstr_to_number, value, 
		      tkstr_to_str, value, 
		      rb_eArgError, 0);
}


/*************************************/

struct cbsubst_info {
    int   size;
    char  *key;
    char  *type;
    ID    *ivar;
    VALUE proc;
};

static void
subst_mark(ptr)
    struct cbsubst_info *ptr;
{
    rb_gc_mark(ptr->proc);
}

static void
subst_free(ptr)
    struct cbsubst_info *ptr;
{
    if (ptr) {
	if (ptr->key != (char*)NULL) free(ptr->key);
	if (ptr->type != (char*)NULL) free(ptr->type);
	if (ptr->ivar != (ID*)NULL) free(ptr->ivar);
	free(ptr);
    }
}

static void
cbsubst_init()
{
    struct cbsubst_info *inf;
    ID *ivar;
    volatile VALUE proc;

    inf = ALLOC(struct cbsubst_info);

    inf->size = 0;

    inf->key = ALLOC_N(char, 1);
    inf->key = ALLOC_N(char, 1);
    inf->key[0] = '\0';

    inf->type = ALLOC_N(char, 1);
    inf->type[0] = '\0';

    ivar = ALLOC_N(ID, 1);
    inf->ivar = ivar;

    proc = rb_hash_new();
    inf->proc = proc;

    rb_const_set(cCB_SUBST, ID_SUBST_INFO, 
		 Data_Wrap_Struct(cSUBST_INFO, subst_mark, subst_free, inf));
}

static VALUE
cbsubst_initialize(argc, argv, self)
    int   argc;
    VALUE *argv;
    VALUE self;
{
    struct cbsubst_info *inf;
    volatile VALUE proc;
    int idx;

    Data_Get_Struct(rb_const_get(rb_obj_class(self), ID_SUBST_INFO), 
		    struct cbsubst_info, inf);

    for(idx = 0; idx < argc; idx++) {
	rb_ivar_set(self, inf->ivar[idx], argv[idx]);
    }

    return self;
}

static VALUE
cbsubst_get_subst_key(self, str)
    VALUE self;
    VALUE str;
{
    volatile VALUE list;
    volatile VALUE ret;
    int i, len;
    char *buf, *ptr;

    list = rb_funcall(cTclTkLib, ID_split_tklist, 1, str);

    len = RARRAY(list)->len;
    buf = ALLOC_N(char, len + 1);

    for(i = 0; i < len; i++) {
	ptr = RSTRING(RARRAY(list)->ptr[i])->ptr;
	if (*ptr == '%' && *(ptr + 2) == '\0') {
	    *(buf + i) = *(ptr + 1);
	} else {
	    *(buf + i) = ' ';
	}
    }
    *(buf + len) = '\0';

    ret = rb_str_new2(buf);
    free(buf);
    return ret;
}

static VALUE
cbsubst_get_all_subst_keys(self)
    VALUE self;
{
    struct cbsubst_info *inf;
    char *buf, *ptr;
    int i, len;
    volatile VALUE ret;

    Data_Get_Struct(rb_const_get(self, ID_SUBST_INFO), 
		    struct cbsubst_info, inf);

    len = strlen(inf->key);
    buf = ALLOC_N(char, 3*len);
    ptr = buf;
    for(i = 0; i < len; i++) {
	*(ptr++) = '%';
	*(ptr++) = *(inf->key + i);
	*(ptr++) = ' ';
    }
    *(buf + 3*len) = '\0';

    ret = rb_ary_new3(2, rb_str_new2(inf->key), rb_str_new2(buf));

    free(buf);

    return ret;
}

static VALUE
cbsubst_table_setup(self, key_inf, proc_inf)
    VALUE self;
    VALUE key_inf;
    VALUE proc_inf;
{
    struct cbsubst_info *subst_inf;
    int idx;
    int len = RARRAY(key_inf)->len;
    char *key = ALLOC_N(char, len + 1);
    char *type = ALLOC_N(char, len + 1);
    ID *ivar = ALLOC_N(ID, len + 1);
    volatile VALUE proc = rb_hash_new();
    volatile VALUE inf;

    /* init */
    subst_inf = ALLOC(struct cbsubst_info);
    subst_inf->size = len;
    subst_inf->key  = key;
    subst_inf->type = type;
    subst_inf->ivar = ivar;
    subst_inf->proc = proc;

    /*
     * keys : array of [subst, type, ivar]
     *         subst ==> char code 
     *         type  ==> char code 
     *         ivar  ==> symbol
     */
    for(idx = 0; idx < len; idx++) {
	inf = RARRAY(key_inf)->ptr[idx];
	if (TYPE(inf) != T_ARRAY) continue;
	*(key  + idx) = (char)NUM2INT(RARRAY(inf)->ptr[0]);
	*(type + idx) = (char)NUM2INT(RARRAY(inf)->ptr[1]);

	*(ivar + idx) 
	    = rb_intern(
		RSTRING(
		  rb_str_cat2(rb_str_new2("@"), 
			      rb_id2name(SYM2ID(RARRAY(inf)->ptr[2])))
		)->ptr
	      );

	rb_attr(self, SYM2ID(RARRAY(inf)->ptr[2]), 1, 0, Qtrue);
    }
    *(key + len) = '\0';
    *(type + len) = '\0';

    /*
     * procs : array of [type, proc]
     *         type  ==> char code 
     *         proc  ==> proc/method/obj (must respond to 'call')
     */
    len = RARRAY(proc_inf)->len;
    for(idx = 0; idx < len; idx++) {
	inf = RARRAY(proc_inf)->ptr[idx];
	if (TYPE(inf) != T_ARRAY) continue;
	rb_hash_aset(proc, RARRAY(inf)->ptr[0], RARRAY(inf)->ptr[1]);
    }

    rb_const_set(self, ID_SUBST_INFO, 
		 Data_Wrap_Struct(cSUBST_INFO, subst_mark, 
				  subst_free, subst_inf));

    return self;
}

static VALUE
cbsubst_scan_args(self, arg_key, val_ary)
    VALUE self;
    VALUE arg_key;
    VALUE val_ary;
{
    struct cbsubst_info *inf;
    int idx;
    int len = RARRAY(val_ary)->len;
    char c;
    char *ptr;
    volatile VALUE dst = rb_ary_new2(len);
    volatile VALUE proc;

    Data_Get_Struct(rb_const_get(self, ID_SUBST_INFO), 
		    struct cbsubst_info, inf);

    RARRAY(dst)->len = 0;
    for(idx = 0; idx < len; idx++) {
	if (idx >= RSTRING(arg_key)->len) {
	    proc = Qnil;
	} else if (*(RSTRING(arg_key)->ptr + idx) == ' ') {
	    proc = Qnil;
	} else {
	  ptr = strchr(inf->key, *(RSTRING(arg_key)->ptr + idx));
	  if (ptr == (char*)NULL) {
	    proc = Qnil;
	  } else {
	    c = *(inf->type + (ptr - inf->key));
	    proc = rb_hash_aref(inf->proc, INT2FIX(c));
	  }
	}

	if (NIL_P(proc)) {
	    RARRAY(dst)->ptr[RARRAY(dst)->len++] = RARRAY(val_ary)->ptr[idx];
	} else {
	    RARRAY(dst)->ptr[RARRAY(dst)->len++] 
		= rb_funcall(proc, ID_call, 1, RARRAY(val_ary)->ptr[idx]);
	}
    }

    return dst;
}

static VALUE
cbsubst_inspect(self)
    VALUE self;
{
    return rb_str_new2("CallbackSubst");
}

static VALUE
substinfo_inspect(self)
    VALUE self;
{
    return rb_str_new2("SubstInfo");
}

/*************************************/

static VALUE
tk_cbe_inspect(self)
    VALUE self;
{
    return rb_str_new2("TkCallbackEntry");
}

/*************************************/

static VALUE
tkobj_path(self)
    VALUE self;
{
    return rb_ivar_get(self, ID_at_path);
}

/*************************************/

void
Init_tkutil()
{
    volatile VALUE tmp;

    VALUE cTK = rb_define_class("TkKernel", rb_cObject);
    VALUE mTK = rb_define_module("TkUtil");

    /* --------------------- */
    rb_global_variable(&cMethod);
    cMethod = rb_const_get(rb_cObject, rb_intern("Method"));

    ID_path = rb_intern("path");
    ID_at_path = rb_intern("@path");
    ID_to_eval = rb_intern("to_eval");
    ID_to_s = rb_intern("to_s");
    ID_install_cmd = rb_intern("install_cmd");
    ID_merge_tklist = rb_intern("_merge_tklist");
    ID_call = rb_intern("call");

    /* --------------------- */
    cCB_SUBST = rb_define_class_under(mTK, "CallbackSubst", rb_cObject);
    rb_define_singleton_method(cCB_SUBST, "inspect", cbsubst_inspect, 0);

    cSUBST_INFO = rb_define_class_under(cCB_SUBST, "Info", rb_cObject);
    rb_define_singleton_method(cSUBST_INFO, "inspect", substinfo_inspect, 0);

    ID_SUBST_INFO = rb_intern("SUBST_INFO");
    rb_define_singleton_method(cCB_SUBST, "scan_args", cbsubst_scan_args, 2);
    rb_define_singleton_method(cCB_SUBST, "_get_subst_key", 
			       cbsubst_get_subst_key,  1);
    rb_define_singleton_method(cCB_SUBST, "_get_all_subst_keys", 
			       cbsubst_get_all_subst_keys,  0);
    rb_define_singleton_method(cCB_SUBST, "_setup_subst_table", 
			       cbsubst_table_setup, 2);

    rb_define_method(cCB_SUBST, "initialize", cbsubst_initialize, -1);

    cbsubst_init();

    /* --------------------- */
    rb_global_variable(&cTkCallbackEntry);
    cTkCallbackEntry = rb_define_class("TkCallbackEntry", cTK);
    rb_define_singleton_method(cTkCallbackEntry, "inspect", tk_cbe_inspect, 0);

    /* --------------------- */
    rb_global_variable(&cTkObject);
    cTkObject = rb_define_class("TkObject", cTK);
    rb_define_method(cTkObject, "path", tkobj_path, 0);

    /* --------------------- */
    rb_require("tcltklib");
    rb_global_variable(&cTclTkLib);
    cTclTkLib = rb_const_get(rb_cObject, rb_intern("TclTkLib"));
    ID_split_tklist = rb_intern("_split_tklist");
    ID_toUTF8 = rb_intern("_toUTF8");
    ID_fromUTF8 = rb_intern("_fromUTF8");

    /* --------------------- */
    rb_define_singleton_method(cTK, "new", tk_s_new, -1);

    /* --------------------- */
    rb_global_variable(&TK_None);
    TK_None = rb_obj_alloc(rb_cObject);
    rb_define_const(mTK, "None", TK_None);
    rb_define_singleton_method(TK_None, "to_s", tkNone_to_s, 0);
    rb_define_singleton_method(TK_None, "inspect", tkNone_to_s, 0);
    OBJ_FREEZE(TK_None);

    /* --------------------- */
    rb_global_variable(&CALLBACK_TABLE);
    CALLBACK_TABLE = rb_hash_new();

    /* --------------------- */
    rb_define_singleton_method(mTK, "eval_cmd", tk_eval_cmd, -1);
    rb_define_singleton_method(mTK, "callback", tk_do_callback, -1);
    rb_define_singleton_method(mTK, "install_cmd", tk_install_cmd, -1);
    rb_define_singleton_method(mTK, "uninstall_cmd", tk_uninstall_cmd, 1);
    rb_define_singleton_method(mTK, "_symbolkey2str", tk_symbolkey2str, 1);
    rb_define_singleton_method(mTK, "hash_kv", tk_hash_kv, -1);
    rb_define_singleton_method(mTK, "_get_eval_string", 
			       tk_get_eval_string, -1);
    rb_define_singleton_method(mTK, "_get_eval_enc_str", 
			       tk_get_eval_enc_str, 1);

    rb_define_singleton_method(mTK, "bool", tcl2rb_bool, 1);
    rb_define_singleton_method(mTK, "number", tcl2rb_number, 1);
    rb_define_singleton_method(mTK, "string", tcl2rb_string, 1);
    rb_define_singleton_method(mTK, "num_or_str", tcl2rb_num_or_str, 1);

    rb_define_method(mTK, "_toUTF8", tk_toUTF8, -1);
    rb_define_method(mTK, "_fromUTF8", tk_fromUTF8, -1);
    rb_define_method(mTK, "_symbolkey2str", tk_symbolkey2str, 1);
    rb_define_method(mTK, "hash_kv", tk_hash_kv, -1);
    rb_define_method(mTK, "_get_eval_string", tk_get_eval_string, -1);
    rb_define_method(mTK, "_get_eval_enc_str", tk_get_eval_enc_str, 1);
    rb_define_method(mTK, "_conv_args", tk_conv_args, -1);

    rb_define_method(mTK, "bool", tcl2rb_bool, 1);
    rb_define_method(mTK, "number", tcl2rb_number, 1);
    rb_define_method(mTK, "string", tcl2rb_string, 1);
    rb_define_method(mTK, "num_or_str", tcl2rb_num_or_str, 1);

    /* --------------------- */
}