/*
    HS_DollyCam - Marker helper (separate script to save Controller memory)
    - Receives link_message MC_CMD:
        "SHOW|N"  -> rez markers for first N presets found
        "HIDE"    -> cleanup markers
    - Listens MARKER_CH for HELLO/CLICK
    - On CLICK sends MC_EVT_CLICK with payload idx to Controller
*/

integer MC_CMD = 5100;
integer MC_EVT_CLICK = 5101;

string  MARKER_OBJECT = "HS_CamMarker";
integer MARKER_CH = -880088;

key gOwner;
integer gShowToken = 0;

// [key objKey, integer idx, vector pos, rotation rot] repeating
list gMarkers;

string PRE_KEY(integer idx) { return "P" + (string)idx; }

vector   gTmpPos;
vector   gTmpFoc;
rotation gTmpRot;

say(string s) { llOwnerSay(s); }

integer isValidIdx(integer idx) { return (idx > 0); }

integer loadPreset(integer idx)
{
    string data = llLinksetDataRead(PRE_KEY(idx));
    if (data == "") return FALSE;

    list p = llParseString2List(data, ["|"], []);
    if (llGetListLength(p) < 10) return FALSE;

    gTmpPos = <(float)llList2String(p,0),(float)llList2String(p,1),(float)llList2String(p,2)>;
    gTmpFoc = <(float)llList2String(p,3),(float)llList2String(p,4),(float)llList2String(p,5)>;
    gTmpRot = <(float)llList2String(p,6),(float)llList2String(p,7),(float)llList2String(p,8),(float)llList2String(p,9)>;
    return TRUE;
}

rotation markerRotFromPosFocus(vector pos, vector focus)
{
    vector fwd = llVecNorm(focus - pos);
    vector up = <0,0,1>;
    vector left = up % fwd;
    if (llVecMag(left) < 0.0001) left = <1,0,0>;
    else left = llVecNorm(left);
    vector up2 = llVecNorm(fwd % left);
    return llAxes2Rot(left, up2, fwd);
}

markersClearLocal()
{
    gMarkers = [];
}

integer markersFind(key obj)
{
    integer i;
    for (i = 0; i < llGetListLength(gMarkers); i += 4) {
        if (llList2Key(gMarkers, i) == obj) return i;
    }
    return -1;
}

markersHide()
{
    integer i;
    for (i = 0; i < llGetListLength(gMarkers); i += 4) {
        key obj = llList2Key(gMarkers, i);
        if (obj != NULL_KEY)
            llRegionSayTo(obj, MARKER_CH, "DIE|" + (string)gShowToken);
    }
    markersClearLocal();
    say("Markers cleaned up.");
}

showCams(integer want)
{
    if (llGetInventoryType(MARKER_OBJECT) != INVENTORY_OBJECT) {
        say("Missing marker object in HUD contents: " + MARKER_OBJECT);
        return;
    }

    markersHide();
    gShowToken = (integer)llFrand(2147483647.0);

    vector aPos = llList2Vector(llGetObjectDetails(gOwner, [OBJECT_POS]), 0);
    vector rezPos = aPos + <0,0,1>;

    integer found = 0;
    integer idx;
    for (idx = 1; idx <= 999 && found < want; ++idx) {
        if (!loadPreset(idx)) jump cont;
        vector pos = gTmpPos;
        vector foc = gTmpFoc;
        rotation mrot = markerRotFromPosFocus(pos, foc);

        llRezObject(MARKER_OBJECT, rezPos, ZERO_VECTOR, ZERO_ROTATION, idx);

        gMarkers += [NULL_KEY, idx, pos, mrot];
        found++;
@cont;
    }

    say("Showing cams: " + (string)found + " (token " + (string)gShowToken + ")");
}

default
{
    state_entry()
    {
        gOwner = llGetOwner();
        llListen(MARKER_CH, "", "", "");
    }

    attach(key id)
    {
        if (id == NULL_KEY) {
            markersHide();
        } else {
            gOwner = llGetOwner();
        }
    }

    link_message(integer sender, integer num, string str, key id)
    {
        if (num != MC_CMD) return;
        if (id != gOwner) return;

        str = llStringTrim(str, STRING_TRIM);
        if (str == "") return;

        list p = llParseString2List(str, ["|"], []);
        string cmd = llToUpper(llList2String(p, 0));

        if (cmd == "HIDE") {
            markersHide();
            return;
        }
        if (cmd == "SHOW") {
            integer want = 12;
            if (llGetListLength(p) >= 2) want = (integer)llList2String(p, 1);
            if (want < 1) want = 1;
            if (want > 30) want = 30;
            showCams(want);
            return;
        }
    }

    object_rez(key id)
    {
        integer i;
        for (i = 0; i < llGetListLength(gMarkers); i += 4) {
            if (llList2Key(gMarkers, i) == NULL_KEY) {
                integer idx = llList2Integer(gMarkers, i+1);
                vector pos = llList2Vector(gMarkers, i+2);
                rotation rot = llList2Rot(gMarkers, i+3);

                gMarkers = llListReplaceList(gMarkers, [id], i, i);

                llRegionSayTo(id, MARKER_CH,
                    "SET|" + (string)gShowToken + "|" + (string)idx + "|" + (string)pos + "|" + (string)rot
                );
                return;
            }
        }
    }

    listen(integer channel, string name, key id, string msg)
    {
        if (channel != MARKER_CH) return;

        list p = llParseString2List(msg, ["|"], []);
        if (llGetListLength(p) < 2) return;

        string typ = llToUpper(llList2String(p,0));
        integer tok = (integer)llList2String(p,1);
        if (tok != gShowToken) return;

        if (typ == "HELLO") {
            integer at = markersFind(id);
            if (at >= 0) {
                integer idx = llList2Integer(gMarkers, at+1);
                vector pos = llList2Vector(gMarkers, at+2);
                rotation rot = llList2Rot(gMarkers, at+3);

                llRegionSayTo(id, MARKER_CH,
                    "SET|" + (string)gShowToken + "|" + (string)idx + "|" + (string)pos + "|" + (string)rot
                );
            }
            return;
        }

        if (typ == "CLICK" && llGetListLength(p) >= 3) {
            integer idx2 = (integer)llList2String(p,2);
            if (!isValidIdx(idx2)) return;

            // Inform Controller (it will stop playlist + move camera)
            llMessageLinked(LINK_SET, MC_EVT_CLICK, (string)idx2, gOwner);
            return;
        }
    }
}