// =====================================================================
//  Colour Menu
//  skimi3d script library
//  https://grid.skimi3d.com/scripts/colour-menu
//
//  Touch it, pick a colour, and the prim takes it. The wall of a house
//  somebody is buying, a car in a showroom, a dress on a stand, the
//  cushions in a room they are trying out.
//
//  Plain LSL.
// =====================================================================


// ---------------------------------------------------------------------
//  Settings
// ---------------------------------------------------------------------

// The colours offered, as a name and then the colour it stands for.
// The names become the buttons, so keep them to about eleven
// characters, and put them in the order you want them shown.
list COLOURS = [
    "White",  <1.00, 1.00, 1.00>,
    "Bone",   <0.94, 0.90, 0.82>,
    "Sand",   <0.85, 0.74, 0.55>,
    "Rust",   <0.65, 0.28, 0.16>,
    "Moss",   <0.36, 0.45, 0.28>,
    "Slate",  <0.35, 0.39, 0.44>,
    "Ink",    <0.10, 0.11, 0.14>,
    "Rose",   <0.90, 0.60, 0.62>,
    "Sky",    <0.55, 0.72, 0.90>,
    "Gold",   <0.85, 0.68, 0.25>,
    "Plum",   <0.42, 0.24, 0.42>,
    "Sea",    <0.20, 0.52, 0.52>
];

// Which face takes the colour. -1 is every face; a single face number
// paints the cushion and leaves the frame.
integer FACE = -1;

// Colour every prim in the linkset rather than only this one.
integer WHOLE_LINKSET = FALSE;

// The line above the buttons.
string HEADING = "Which colour?";

// Who may change it. 0 = everyone, 1 = only the owner, 2 = same group.
integer WHO_MAY_CHANGE = 0;


// ---------------------------------------------------------------------
//  Everything below here is the machinery
// ---------------------------------------------------------------------

float   PATIENCE = 60.0;    // how long the menu waits for an answer
integer PER_PAGE = 9;       // a dialog holds nine buttons and no more

integer gChannel = 0;
integer gListen  = 0;
integer gPage    = 0;


// Just the names, which are the buttons.
list names()
{
    list out = [];
    integer n = llGetListLength(COLOURS);
    integer i;

    // Two entries make one colour, so the step is two and not one.
    for (i = 0; i < n; i += 2)
    {
        out += [llList2String(COLOURS, i)];
    }

    return out;
}


list page(integer n, list all)
{
    integer total = llGetListLength(all);
    if (total <= PER_PAGE) return all;

    integer room  = PER_PAGE - 2;
    integer pages = (total + room - 1) / room;

    if (n < 0) n = pages - 1;
    if (n >= pages) n = 0;
    gPage = n;

    integer from = n * room;
    integer to   = from + room - 1;
    if (to > total - 1) to = total - 1;

    return llList2List(all, from, to) + ["< Back", "Next >"];
}


integer privateChannel(key who)
{
    return -1 - (integer)("0x" + llGetSubString((string)who, 0, 6));
}


menu(key who, integer n)
{
    if (gListen) llListenRemove(gListen);

    gChannel = privateChannel(who);
    gListen  = llListen(gChannel, "", who, "");

    llDialog(who, HEADING, page(n, names()), gChannel);
    llSetTimerEvent(PATIENCE);
}


shut()
{
    if (gListen) llListenRemove(gListen);
    gListen = 0;
    gPage   = 0;
    llSetTimerEvent(0.0);
}


paint(string name)
{
    integer at = llListFindList(COLOURS, [name]);
    if (at == -1) return;

    // The colour sits directly after its name, which is what the stride
    // of two is for.
    vector c = llList2Vector(COLOURS, at + 1);

    integer link = LINK_THIS;
    if (WHOLE_LINKSET) link = LINK_SET;

    llSetLinkPrimitiveParamsFast(link, [PRIM_COLOR, FACE, c, 1.0]);
}


integer mayChange(key who)
{
    if (WHO_MAY_CHANGE == 1) return who == llGetOwner();
    if (WHO_MAY_CHANGE == 2) return llSameGroup(who);
    return TRUE;
}


default
{
    state_entry()
    {
        shut();
    }

    touch_start(integer total)
    {
        key who = llDetectedKey(0);

        if (!mayChange(who))
        {
            llRegionSayTo(who, 0, "This one is not yours to change.");
            return;
        }

        menu(who, 0);
    }

    listen(integer channel, string name, key who, string message)
    {
        if (message == "Next >")
        {
            menu(who, gPage + 1);
            return;
        }

        if (message == "< Back")
        {
            menu(who, gPage - 1);
            return;
        }

        shut();
        paint(message);
    }

    timer()
    {
        shut();
    }

    on_rez(integer start)
    {
        llResetScript();
    }
}