/* ==================================================================

    FILE: "/home/joze/src/tclreadline/tclreadline.c"
    LAST MODIFICATION: "Tue Sep 14 00:57:33 1999 (joze)"
    (C) 1998, 1999 by Johannes Zellner, <johannes@zellner.org>
    $Id$
    ---

    tclreadline -- gnu readline for tcl
    Copyright (C) 1999  Johannes Zellner

/*
 * forward declarations.
 */
char* stripleft(char* in);
char* stripright(char* in);
char* stripwhite(char* in);
int TclReadlineLineComplete(void);
void TclReadlineTerminate(int state);
char* TclReadlineQuote(char* text, char* quotechars);
int TclReadlineCmd(ClientData clientData, Tcl_Interp* interp,
    int argc, char** argv);
void TclReadlineReadHandler(ClientData clientData, int mask);
void TclReadlineLineCompleteHandler(char* ptr);
int Tclreadline_SafeInit(Tcl_Interp* interp);
int Tclreadline_Init(Tcl_Interp* interp);
int TclReadlineInitialize(Tcl_Interp* interp, char* historyfile);
int blank_line(char* str);
char** TclReadlineCompletion(char* text, int start, int end);
char* TclReadline0generator(char* text, int state);
char* TclReadlineKnownCommands(char* text, int state, int mode);
int TclReadlineParse(char** args, int maxargs, char* buf);

enum { 
    LINE_PENDING = -1,
    LINE_EOF = (1 << 8),
    LINE_COMPLETE = (1 << 9)
};

/**
 * global variables
 */

static int tclrl_state = TCL_OK;
static char* tclrl_eof_string = (char*) NULL;

static char* tclrl_custom_completer = (char*) NULL;
static char* tclrl_last_line = (char*) NULL;
static int tclrl_use_builtin_completer = 1;
static int tclrl_history_length = -1;
Tcl_Interp* tclrl_interp = (Tcl_Interp*) NULL;


char*
stripleft(char* in)

char*
stripwhite(char* in)
{
    stripleft(in);
    stripright(in);
    return in;
}

int
TclReadlineLineComplete(void)
{
    return !(tclrl_state == LINE_PENDING);
}

void
TclReadlineTerminate(int state)
{
    tclrl_state = state;
    rl_callback_handler_remove();
}

char*
TclReadlineQuote(char* text, char* quotechars)
{
    char* ptr;
    char* result_c;
    int i, len = strlen(quotechars);

    }
    result_c = strdup(Tcl_DStringValue(&result));
    return result_c;
}

int
TclReadlineCmd(
    ClientData  clientData,
    Tcl_Interp* interp,     /* Current interpreter */
    int         argc,       /* Number of arguments */
    char**      argv        /* Argument strings    */
)
{
    int i, obj_idx, status;
    Tcl_Obj** objv = (Tcl_Obj**) MALLOC((argc + 1) * sizeof(Tcl_Obj *));

    static char *subCmds[] = {
        "read", "initialize", "write", "add", "complete",
        "customcompleter", "builtincompleter", "eofchar",
        (char *) NULL
    };
    enum SubCmdIdx {
        TCLRL_READ, TCLRL_INITIALIZE, TCLRL_WRITE, TCLRL_ADD, TCLRL_COMPLETE,
        TCLRL_CUSTOMCOMPLETER, TCLRL_BUILTINCOMPLETER, TCLRL_EOFCHAR
    };


    Tcl_ResetResult(interp); /* clear the result space */

    for (i = 0;  i < argc;  i++) {
        Tcl_Obj* objPtr = Tcl_NewStringObj(argv[i], -1);
        Tcl_IncrRefCount(objPtr);
        objv[i] = objPtr;
    }
    objv[argc] = 0; /* terminate */

    if (argc < 2) {
        Tcl_WrongNumArgs(interp, 1, objv, "option ?arg arg ...?");
        return TCL_ERROR;
    }
    
    status = Tcl_GetIndexFromObj
        (interp, objv[1], subCmds, "option", 0, (int *) &obj_idx);


    if (status != TCL_OK) {
        FREE(objv)
        return status;
    }

    switch (obj_idx) {

        case TCLRL_READ:

            rl_callback_handler_install(argc == 3 ? argv[2] : "%",
                TclReadlineLineCompleteHandler);

            Tcl_CreateFileHandler(0, TCL_READABLE,
                TclReadlineReadHandler, (ClientData) NULL);

            /**
             * Main Loop.
             * XXX each modification of the global variables
             *     which terminates the main loop must call
             *     rl_callback_handler_remove() to leave
             *     readline in a defined state.          XXX
             */
            tclrl_state = LINE_PENDING;

            while (!TclReadlineLineComplete()) {
#ifdef EXECUTING_MACRO_HACK
                /**
                 * check first, if more characters are
                 * available from _rl_executing_macro,
                 * because Tcl_DoOneEvent() will (naturally)
                 * not detect this `event'.
                 */
                if (_rl_executing_macro)
                    TclReadlineReadHandler((ClientData) NULL, TCL_READABLE);
                else
#endif
                    Tcl_DoOneEvent(TCL_ALL_EVENTS);
            }

            Tcl_DeleteFileHandler(0);

            switch (tclrl_state) {


                case LINE_COMPLETE:

                    return TCL_OK;
                    /* NOTREACHED */
                    break;

                case LINE_EOF:


                    if (tclrl_eof_string)




                        return Tcl_Eval(interp, tclrl_eof_string);
                    else

                        return TCL_OK;
                    /* NOTREACHED */
                    break;




                default:
                    return tclrl_state;
                    /* NOTREACHED */
                    break;
            }



            break;




        case TCLRL_INITIALIZE:




            if (3 != argc) {

                Tcl_WrongNumArgs(interp, 2, objv, "historyfile");
                return TCL_ERROR;
            } else {
                return TclReadlineInitialize(interp, argv[2]);
            }
            break;

        case TCLRL_WRITE:
            if (3 != argc) {

                Tcl_WrongNumArgs(interp, 2, objv, "historyfile");
                return TCL_ERROR;
            }  else if (write_history(argv[2])) {
                Tcl_AppendResult(interp, "unable to write history to `",
                    argv[2], "'\n", (char*) NULL);
                return TCL_ERROR;
            }
            if (tclrl_history_length >= 0) {
                history_truncate_file(argv[2], tclrl_history_length);
            }
            return TCL_OK;
            break;

        case TCLRL_ADD:
            if (3 != argc) {

                Tcl_WrongNumArgs(interp, 2, objv, "completerLine");
                return TCL_ERROR;
            } else if (TclReadlineKnownCommands(argv[2], (int) 0, _CMD_SET)) {
                Tcl_AppendResult(interp, "unable to add command \"",
                    argv[2], "\"\n", (char*) NULL);
            }
            break;

        case TCLRL_COMPLETE:
            if (3 != argc) {

                Tcl_WrongNumArgs(interp, 2, objv, "line");
                return TCL_ERROR;
            } else if (Tcl_CommandComplete(argv[2])) {
                Tcl_AppendResult(interp, "1", (char*) NULL);
            } else {
                Tcl_AppendResult(interp, "0", (char*) NULL);
            }
            break;

        case TCLRL_CUSTOMCOMPLETER:
            if (argc > 3) {

                Tcl_WrongNumArgs(interp, 2, objv, "?scriptCompleter?");
                return TCL_ERROR;
            } else if (3 == argc) {
                if (tclrl_custom_completer)
                    FREE(tclrl_custom_completer);
                if (!blank_line(argv[2]))
                    tclrl_custom_completer = stripwhite(strdup(argv[2]));
            }
            Tcl_AppendResult(interp, tclrl_custom_completer, (char*) NULL);
            break;

        case TCLRL_BUILTINCOMPLETER:
            if (argc > 3) {

                Tcl_WrongNumArgs(interp, 2, objv, "?boolean?");
                return TCL_ERROR;
            } else if (3 == argc) {
                int bool = tclrl_use_builtin_completer;
                if (TCL_OK != Tcl_GetBoolean(interp, argv[2], &bool)) {
                    Tcl_AppendResult(interp,
                        "wrong # args: should be a boolean value.",
                        (char*) NULL);
                    return TCL_ERROR;
                } else {
                    tclrl_use_builtin_completer = bool;
                }
            }
            Tcl_AppendResult(interp, tclrl_use_builtin_completer ? "1" : "0",
                (char*) NULL);
            break;

        case TCLRL_EOFCHAR:
            if (argc > 3) {

                Tcl_WrongNumArgs(interp, 2, objv, "?script?");
                return TCL_ERROR;
            } else if (3 == argc) {
                if (tclrl_eof_string)
                    FREE(tclrl_eof_string);
                if (!blank_line(argv[2]))
                    tclrl_eof_string = stripwhite(strdup(argv[2]));
            }
            Tcl_AppendResult(interp, tclrl_eof_string, (char*) NULL);
            break;

        default:
            goto BAD_COMMAND;
            /* NOTREACHED */
            break;
    }

    return TCL_OK;

BAD_COMMAND:
    Tcl_AppendResult(interp,
        "wrong # args: should be \"readline option ?arg ...?\"",
        (char*) NULL);
    return TCL_ERROR;

}

void
TclReadlineReadHandler(ClientData clientData, int mask)
{
    if (mask & TCL_READABLE) {
#ifdef EXECUTING_MACRO_HACK
        do {
#endif
            rl_callback_read_char();
#ifdef EXECUTING_MACRO_HACK
            /**
             * check, if we're inside a macro and
             * if so, read all macro characters
             * until the next eol.
             */
        } while (_rl_executing_macro && !TclReadlineLineComplete());


#endif
    }
}

void
TclReadlineLineCompleteHandler(char* ptr)
{

    if (!ptr) { /* <c-d> */

        TclReadlineTerminate(LINE_EOF);

    } else {

        /**
         * From version 0.9.3 upwards, all lines are
         * returned, even empty lines. (Only non-empty
         * lines are stuffed in readline's history.)
         * The calling script is responsible for handling
         * empty strings.
         */

        char* expansion = (char*) NULL;
        int status = history_expand(ptr, &expansion);

        if (status >= 1) {
#if 0
            Tcl_Channel channel = Tcl_MakeFileChannel(stdout, TCL_WRITABLE);
            /* Tcl_RegisterChannel(interp, channel); */
            (void) Tcl_WriteChars(channel, expansion, -1);
            Tcl_Flush(channel);
            Tcl_Close(interp, channel);
#else
            /* TODO: make this a valid tcl output */
            printf("%s\n", expansion);
#endif
        } else if (-1 == status) {
            Tcl_AppendResult
                (tclrl_interp, "error in history expansion\n", (char*) NULL);
            TclReadlineTerminate(TCL_ERROR);
        }
        /**
         * TODO: status == 2 ...
         */

        Tcl_AppendResult(tclrl_interp, expansion, (char*) NULL);

#ifdef EXECUTING_MACRO_HACK
        /**
         * don't stuff macro lines
         * into readline's history.
         */
        if(!_rl_executing_macro) {
#endif
            /**
             * don't stuff empty lines
             * into readline's history.
             * don't stuff twice the same
             * line into readline's history.
             */
            if (expansion && *expansion && (!tclrl_last_line ||
                strcmp(tclrl_last_line, expansion))) {
                add_history(expansion);
            }
            if (tclrl_last_line)
                free(tclrl_last_line);
            tclrl_last_line = strdup(expansion);
#ifdef EXECUTING_MACRO_HACK
        }
#endif
        /**
         * tell the calling routines to terminate.
         */
        TclReadlineTerminate(LINE_COMPLETE);
        FREE(ptr);
        FREE(expansion);
    }
}

int
Tclreadline_SafeInit(Tcl_Interp *interp)
{
    return Tclreadline_Init(interp);
}

    return Tcl_PkgProvide(interp, "tclreadline", TCLRL_VERSION);
}

int
TclReadlineInitialize(Tcl_Interp* interp, char* historyfile)
{
    rl_readline_name = "tclreadline";
    /*    rl_special_prefixes = "${\"["; */
    rl_special_prefixes = "$";
    /**
     * default is " \t\n\"\\'`@$><=;|&{("
     * removed "(" <-- arrays
     * removed "{" <-- `${' variables 
     * removed "<" <-- completion lists with < ... >
     * added "[]"
     * added "}"
     */
    /* 11.Sep rl_basic_word_break_characters = " \t\n\"\\@$}=;|&[]"; */
    /* besser (11. Sept) 2. (removed \") */
    /* rl_basic_word_break_characters = " \t\n\\@$}=;|&[]"; */
    /* besser (11. Sept) 3. (removed }) */
    rl_basic_word_break_characters = " \t\n\\@$=;|&[]";
#if 0
    rl_basic_quote_characters = "\"{"; /* XXX ??? XXX */
    rl_completer_quote_characters = "\"";
#endif
    /*
    rl_filename_quote_characters
    = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";

    rl_filename_quoting_function

    }

    if (tclrl_custom_completer) {
        char start_s[BUFSIZ], end_s[BUFSIZ];
        Tcl_Obj* obj;
        Tcl_Obj** objv;
        int objc;
        int state;
        char* quoted_text = TclReadlineQuote(text, "$[]{}\"");
        char* quoted_rl_line_buffer
            = TclReadlineQuote(rl_line_buffer, "$[]{}\"");
        sprintf(start_s, "%d", start);
        sprintf(end_s, "%d", end);
        Tcl_ResetResult(tclrl_interp); /* clear result space */
        state = Tcl_VarEval(tclrl_interp, tclrl_custom_completer,
            " \"", quoted_text, "\" ", start_s, " ", end_s,
            " \"", quoted_rl_line_buffer, "\"", (char*) NULL);
        FREE(quoted_text);
        FREE(quoted_rl_line_buffer);
        if (TCL_OK != state) {

            Tcl_AppendResult (tclrl_interp, " `", tclrl_custom_completer,
                " \"", quoted_text, "\" ", start_s, " ", end_s,
                " \"", quoted_rl_line_buffer, "\"' failed.", (char*) NULL);
            TclReadlineTerminate(state);
            return matches;
        }
        obj = Tcl_GetObjResult(tclrl_interp);
        status = Tcl_ListObjGetElements(tclrl_interp, obj, &objc, &objv);
        if (TCL_OK != status)
            return matches;