// huffware script: menutini library, by fred huffhines.
//
// this is a library script for menuing that provides a way to remote control the
// menu, somewhat.  another script can zing link messages at this script and a menu
// will be shown based on the specified description and buttons.  when the user
// selects an answer, that result is sent back in a link message reply.
//
// this script is licensed by the GPL v3 which is documented at: http://www.gnu.org/licenses/gpl.html
// do not use it in objects without fully realizing you are implicitly accepting that license.
//

// useful constants you might want to change:

integer TIMEOUT_FOR_MENU = 42;
    // timeout for the menu in seconds.
//hmmm: may want this to be selectable from menu request.
//      or may even want to never time out!
//      if we managed a list of ongoing menus, that would work.
//      currently it cannot.

integer DEBUGGING = FALSE;
    // if this is true, then extra info will be printed when handling a menu.

string NEXT_MENU_TEXT = "Next >>";
    // what the next item will say for showing next menu page.

// menutini link message API...
//////////////
// do not redefine these constants.
integer MENUTINI_HUFFWARE_ID = 10009;
    // the unique id within the huffware system for the jaunt script to
    // accept commands on.  this is used in llMessageLinked as the num parameter.
string HUFFWARE_PARM_SEPARATOR = "{~~~}";
    // this pattern is an uncommon thing to see in text, so we use it to separate
    // our commands in link messages.
string HUFFWARE_ITEM_SEPARATOR = "{|||}";
    // used to separate lists of items from each other when stored inside a parameter.
    // this allows lists to be passed as single string parameters if needed.
integer REPLY_DISTANCE = 100008;  // offset added to service's huffware id in reply IDs.
string SHOW_MENU_COMMAND = "#menu#";
    // the command that tells menutini to show a menu defined by parameters
    // that are passed along.  these must be: the menu name, the menu's title
    // (which is really the info to show as content in the main box of the menu),
    // the wrapped list of commands to show as menu buttons, the menu system
    // channel's for listening, and the key to listen to.
    // the reply will include: the menu name, the choice made and the key for
    // the avatar.
//
//////////////
// joins a list of sub-items using the item sentinel for the library.
string wrap_item_list(list to_wrap)
{ return llDumpList2String(to_wrap, HUFFWARE_ITEM_SEPARATOR); }
//
//////////////

// global variables...

list _private_global_buttons;  // holds onto the active set of menu options.
string _private_global_av_key;  // the key for the avatar who clicks the menu.
string _private_global_title;  // holds onto current title text.

integer _menu_base_start = 0;  // position in the items of the current menu.

integer listening_id = 0;
    // the current id of our listening for the menu.  it's an id returned by LSL
    // that we need to track so we can cancel the listen.

integer menu_system_channel = 0;
    // messages come back to us from this channel when user clicks the dialog.
    // this is set later and the default is meaningless.

string global_menu_name = "";
    // hangs onto the current menu's name.

//hmmm: note; to manage multiple concurrent menus on different channels,
//      we must make these into lists.  then the timeouts should apply
//      individually to these instead of overall (if we even do timeouts;
//      it's nicer if menus never stop being active).


// displays the menu requested.  it's "menu_name" is an internal name that is
// not displayed to the user.  the "title" is the content shown in the main area
// of the menu.  "commands_in" is the list of menu items to show as buttons.
// the "menu_channel" is where the user's clicked response will be sent.  the
// "listen_to" key is the avatar expected to click the menu, which is needed to
// listen to his response.
show_menu(string menu_name, string title, list buttons,
    integer menu_channel, key listen_to)
{
    // save our new parms.
    global_menu_name = menu_name;
    _private_global_title = title;
    _private_global_buttons = buttons;
    menu_system_channel = menu_channel;
    _private_global_av_key = listen_to;
//log_it("showing menu to " + llKey2Name(listen_to) + " with key " + (string)listen_to);
    if (DEBUGGING) {
        log_it("menu name: " + global_menu_name);
        log_it("title: " + _private_global_title);
        log_it("buttons: " + (string)buttons);
        log_it("channel: " + (string)menu_system_channel);
        log_it("listen key: " + (string)listen_to);
    }

    integer add_next = FALSE;  // true if we should add a next menu item.

    // the math here incorporates current button position.
    integer current = _menu_base_start;
    integer max_buttons = llGetListLength(buttons) - current;

    if (max_buttons > 12) {
        // limitation of SL: menus have a max of 12 buttons.
        max_buttons = 12;
        add_next = TRUE;
    } else if (llGetListLength(buttons) > 12) {
        // we already have been adding next.  let's make sure this gets
        // a wrap-around next button.
        add_next = TRUE;
    }
    // chop out what we can use in a menu.
    list trunc_buttons = llList2List(buttons, current, current + max_buttons - 1);
    if (add_next) {
        // we were asked to add a menu item for the next screen.
        trunc_buttons = llList2List(trunc_buttons, 0, 10) + NEXT_MENU_TEXT;
    }

    listening_id = llListen(menu_channel, "", listen_to, "");
    list commands;
    integer i;
    // take only the prefix of the string, to avoid getting a length complaint.
    for (i = 0; i < llGetListLength(trunc_buttons); i++) {
        string curr = llList2String(trunc_buttons, i);
        integer last_pos = 23;  // default maximum, highest possible is 24.
        if (llStringLength(curr) - 1 < last_pos) last_pos = llStringLength(curr) - 1;
        curr = llGetSubString(curr, 0, last_pos);
        commands += curr;
    }
    llDialog(listen_to, title, commands, menu_channel);
    llSetTimerEvent(TIMEOUT_FOR_MENU);
}

// shuts down any connection we might have had with any active menu.  we will not
// send any responses after this point (although we might already have responded when
// the user clicked the menu).
clear_menu()
{
    llListenRemove(listening_id);
    llSetTimerEvent(0.0);
}

// a simple version of a reply for a command that has been executed.  the parameters
// might contain an outcome or result of the operation that was requested.
// ours do differ from normal in that we send back the channel as the number parameter
// instead of enforcing that being MENU_HUFFWARE_ID.
send_reply(integer destination, integer channel, list parms, string command)
{
    llMessageLinked(destination, channel, command,
        llDumpList2String(parms, HUFFWARE_PARM_SEPARATOR));
}

// processes the menu requests.
handle_link_message(integer sender, integer huff_id, string msg, key id)
{
    if (huff_id != MENUTINI_HUFFWARE_ID) return;  // not for us.

    if (msg == SHOW_MENU_COMMAND) {
        _menu_base_start = 0;  // reset the position in the menus.
        // separate the list out.
//log_it("id showing: " + (string)id);
        list parms = llParseStringKeepNulls(id, [HUFFWARE_PARM_SEPARATOR], []);
//log_it("parm len " + (string)llGetListLength(parms) + ", parms are: " + (string)parms);
        // toss any existing menu info.
        clear_menu();
//log_it("key here early: " + llList2String(parms, 4));
        show_menu(llList2String(parms, 0), llList2String(parms, 1),
            llParseStringKeepNulls(llList2String(parms, 2),
                [HUFFWARE_ITEM_SEPARATOR], []),
            (integer)llList2String(parms, 3),
            (key)llList2String(parms, 4));
    }
}

// process the response when the user chooses a menu item.  this causes our
// caller to be told what was selected.
process_menu_response(integer channel, string name, key id, string message)
{
    if (channel != menu_system_channel) return;  // not for us.

    if (message == NEXT_MENU_TEXT) {
        // this is the special choice, so we need to go to the next page.
        _menu_base_start += 11;
        if (_menu_base_start > llGetListLength(_private_global_buttons)) {
            // we have wrapped around the list.  go to the start again.
            _menu_base_start = 0;
        }
        show_menu(global_menu_name, _private_global_title,
            _private_global_buttons, menu_system_channel,
            _private_global_av_key);
        return;  // handled by opening a new menu.
    }
    
    string calculated_name;
    integer indy;
    // first try for an exact match.
    for (indy = 0; indy < llGetListLength(_private_global_buttons); indy++) {
        string curr = llList2String(_private_global_buttons, indy);
        if (curr == message) {
            // correct the answer based on the full button string.
            calculated_name = curr;
        }
    }
    if (calculated_name == "") {
        // try an imprecise match if the exact matching didn't work.
        for (indy = 0; indy < llGetListLength(_private_global_buttons); indy++) {
            string curr = llList2String(_private_global_buttons, indy);
            if (is_prefix(curr, message)) {
                // correct the answer based on the full button string.
                calculated_name = curr;
            }
        }
    }
    if (calculated_name != "") {
        // only send a response if that menu choice made sense to us.
        send_reply(LINK_THIS, MENUTINI_HUFFWARE_ID + REPLY_DISTANCE,
            [ global_menu_name, calculated_name, _private_global_av_key ],
            SHOW_MENU_COMMAND);
    }
}

//////////////
// from hufflets...

integer debug_num = 0;

// a debugging output method.  can be disabled entirely in one place.
log_it(string to_say)
{
    debug_num++;
    // tell this to the owner.    
    llOwnerSay(llGetScriptName() + "[" + (string)debug_num + "] " + to_say);
    // say this on open chat, but use an unusual channel.
//    llSay(108, llGetScriptName() + "[" + (string)debug_num + "] " + to_say);
}

//////////////

// returns TRUE if the "prefix" string is the first part of "compare_with".
integer is_prefix(string compare_with, string prefix)
{ return (llSubStringIndex(compare_with, prefix) == 0); }

//////////////

//////////////
// huffware script: auto-retire, by fred huffhines, version 2.8.
// distributed under BSD-like license.
//   !!  keep in mind that this code must be *copied* into another
//   !!  script that you wish to add auto-retirement capability to.
// when a script has auto_retire in it, it can be dropped into an
// object and the most recent version of the script will destroy
// all older versions.
//
// the version numbers are embedded into the script names themselves.
// the notation for versions uses a letter 'v', followed by two numbers
// in the form "major.minor".
// major and minor versions are implicitly considered as a floating point
// number that increases with each newer version of the script.  thus,
// "hazmap v0.1" might be the first script in the "hazmap" script continuum,
// and "hazmap v3.2" is a more recent version.
//
// example usage of the auto-retirement script:
//     default {
//         state_entry() {
//            auto_retire();  // make sure newest addition is only version of script.
//        }
//     }
// this script is partly based on the self-upgrading scripts from markov brodsky
// and jippen faddoul.
//////////////
auto_retire() {
    string self = llGetScriptName();  // the name of this script.
    list split = compute_basename_and_version(self);
    if (llGetListLength(split) != 2) return;  // nothing to do for this script.
    string basename = llList2String(split, 0);  // script name with no version attached.
    string version_string = llList2String(split, 1);  // the version found.
    integer posn;
    // find any scripts that match the basename.  they are variants of this script.
    for (posn = llGetInventoryNumber(INVENTORY_SCRIPT) - 1; posn >= 0; posn--) {
        string curr_script = llGetInventoryName(INVENTORY_SCRIPT, posn);
        if ( (curr_script != self) && (llSubStringIndex(curr_script, basename) == 0) ) {
            // found a basic match at least.
            list inv_split = compute_basename_and_version(curr_script);
            if (llGetListLength(inv_split) == 2) {
                // see if this script is more ancient.
                string inv_version_string = llList2String(inv_split, 1);  // the version found.
                // must make sure that the retiring script is completely the identical basename;
                // just matching in the front doesn't make it a relative.
                if ( (llList2String(inv_split, 0) == basename)
                    && ((float)inv_version_string < (float)version_string) ) {
                    // remove script with same name from inventory that has inferior version.
                    llRemoveInventory(curr_script);
                }
            }
        }
    }
}
//
// separates the base script name and version number.  used by auto_retire.
list compute_basename_and_version(string to_chop_up)
{
    // minimum script name is 2 characters plus a version.
    integer space_v_posn;
    // find the last useful space and 'v' combo.
    for (space_v_posn = llStringLength(to_chop_up) - 3;
        (space_v_posn >= 2) && (llGetSubString(to_chop_up, space_v_posn, space_v_posn + 1) != " v");
        space_v_posn--) {
        // look for space and v but do nothing else.
    }
    if (space_v_posn < 2) return [];  // no space found.
    // now we zoom through the stuff after our beloved v character and find any evil
    // space characters, which are most likely from SL having found a duplicate item
    // name and not so helpfully renamed it for us.
    integer indy;
    for (indy = llStringLength(to_chop_up) - 1; indy > space_v_posn; indy--) {
        if (llGetSubString(to_chop_up, indy, indy) == " ") {
            // found one; zap it.  since we're going backwards we don't need to
            // adjust the loop at all.
            to_chop_up = llDeleteSubString(to_chop_up, indy, indy);
        }
    }
    string full_suffix = llGetSubString(to_chop_up, space_v_posn, -1);
    // ditch the space character for our numerical check.
    string chop_suffix = llGetSubString(full_suffix, 1, llStringLength(full_suffix) - 1);
    // strip out a 'v' if there is one.
    if (llGetSubString(chop_suffix, 0, 0) == "v")
        chop_suffix = llGetSubString(chop_suffix, 1, llStringLength(chop_suffix) - 1);
    // if valid floating point number and greater than zero, that works for our version.
    string basename = to_chop_up;  // script name with no version attached.
    if ((float)chop_suffix > 0.0) {
        // this is a big success right here.
        basename = llGetSubString(to_chop_up, 0, -llStringLength(full_suffix) - 1);
        return [ basename, chop_suffix ];
    }
    // seems like we found nothing useful.
    return [];
}
//
//////////////

//hmmm: extract this code to a menutini example!

//////////////
// how to invoke a menu (assuming menutini is in same prim as calling script):
//
list buttons;  // holds onto the set of menu options.
//
integer random_channel() { return -(integer)(llFrand(40000) + 20000); }
//
example_invocation()
{
    string menu_name = "grumfazoid";
    string title = "These united colors of ben's futon have unfortunately run.";
    buttons = [ "garp out", "sklonar", "fuzzlenog" ];
    integer menu_channel = random_channel();
    key listen_to = llGetOwner();
    llMessageLinked(LINK_THIS, MENUTINI_HUFFWARE_ID, SHOW_MENU_COMMAND,
        menu_name + HUFFWARE_PARM_SEPARATOR
        + title + HUFFWARE_PARM_SEPARATOR
        + wrap_item_list(buttons) + HUFFWARE_PARM_SEPARATOR
        + (string)menu_channel + HUFFWARE_PARM_SEPARATOR
        + (string)listen_to);
}
//
// how to handle the response message when the user chooses a button.
//
react_to_menu(string menu_name, string which_choice)
{
    // one might use the menu_name when dealing with multiple different menus.

    integer indy = 0;
    // find the specified item and process it.
    while (indy < llGetListLength(buttons)) {
        // see if the current destination matches.
        if (llSubStringIndex(llList2String(buttons, indy), which_choice) == 0) {
            // this is the chosen item.
//            process_menu_item(indy);  // using numerical numbering.
// this function must be implemented in your own code; it is what handles the
// user picking a particular button on the menu.
            return;            
        }
        indy++;
    }
    llSay(0, "did not find menu option");
}

// an example for menu handling.  this gets the response from menutini library
// and calls the menu processing method "react_to_menu".
example_handle_link_message(integer sender, integer num, string msg, key id)
{
    if (num != MENUTINI_HUFFWARE_ID + REPLY_DISTANCE) return;  // not for us.
    if (msg != SHOW_MENU_COMMAND) return;  // also not for us.
    list parms = llParseStringKeepNulls(id, [HUFFWARE_PARM_SEPARATOR], []);
    string menu_name = llList2String(parms, 0);
    string which_choice = llList2String(parms, 1);
    react_to_menu(menu_name, which_choice);
}

// then inside a state, you need an event handler like so:
//
// link_message(integer sender, integer num, string msg, key id)
// { example_handle_link_message(sender, num, msg, id); }

//
// end invocation sample code...
//////////////

default
{
    state_entry() { if (llSubStringIndex(llGetObjectName(),  "huffotronic") < 0) state real_default; }
    on_rez(integer parm) { state rerun; }
}
state rerun { state_entry() { state default; } }

state real_default
{
    state_entry() { auto_retire(); }

    link_message(integer sender, integer huff_id, string msg, key id)
    { handle_link_message(sender, huff_id, msg, id); }

    listen(integer channel, string name, key id, string message)
    { process_menu_response(channel, name, id, message); }
    
    // if the timer goes off, then the user has ignored the menu for longer than the
    // timeout.  we need to turn off our listen and ignore that menu.
    timer() { clear_menu(); }
}