// huffware script: fade prim, by fred huffhines
//
// makes an object fade in and out of visibility.
//
// 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.
//

// constants...

float OPACITY_MIN = 0.4;  // the lowest value to allow the transparency to reach.
float OPACITY_MAX = 1.0;  // the highest value to allow the transparent
  // if you set this above the max of 1.0, it keeps the object solid for longer.

float TIMER_INTERVAL = 1.5;  // how often do we adjust our appearance?

// variables...

float current_opacity = 0.42;  // what is our current opacity?
float current_adjustment = 0.2;  // amount added/removed each time.

//////////////
// 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 an unusual channel for chat if it's not intended for general public.
//    llSay(108, llGetScriptName() + "[" + (string)debug_num + "] " + to_say);
    // say this on open chat that anyone can hear.  we take off the bling for this one.
//    llSay(0, to_say);
}
//
//////////////

//////////////
// huffware script: auto-retire, by fred huffhines, version 2.4.
// distributed under BSD-like license.
//   partly based on the self-upgrading scripts from markov brodsky and jippen faddoul.
// the function auto_retire() should be added *inside* a version numbered script that
// you wish to give the capability of self-upgrading.
//   this script supports a notation for versions embedded in script names where a 'v'
// is followed by a number in the form "major.minor", e.g. "grunkle script by ted v8.2".
// when the containing script is dropped into an object with a different version, the
// most recent version eats any existing ones.
//   keep in mind that this code must be *copied* into your script you wish to add
// auto-retirement capability to.
// example usage of the auto-retirement script:
//     default {
//         state_entry() {
//            auto_retire();  // make sure newest addition is only version of script.
//        }
//     }
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--) {
//log_it("invpo=" + (string)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.
//log_it("pos=" + (string)space_v_posn);
    }
    if (space_v_posn < 2) return [];  // no space found.
//log_it("space v@" + (string)space_v_posn);
    // 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--) {
//log_it("indy=" + (string)space_v_posn);
        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);
//log_it("saw case of previously redundant item, aieee.  flattened: " + to_chop_up);
        }
    }
    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 [];
}
//
//////////////

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();
        llSetTimerEvent(TIMER_INTERVAL);
    }

    timer() {
        llSetTimerEvent(0);
        llSetLinkAlpha(LINK_SET, current_opacity, ALL_SIDES);
        current_opacity += current_adjustment;
        if (current_opacity < OPACITY_MIN) { current_opacity = OPACITY_MIN; current_adjustment *= -1.0; }
        if (current_opacity > OPACITY_MAX) { current_opacity = OPACITY_MAX; current_adjustment *= -1.0; }
        llSetTimerEvent(TIMER_INTERVAL);
    }
}