// The Ekklesia Classroom desktop.
//
// Plasma runs this once, when a session has no panel yet, and again on
// demand — `plasma-apply-lookandfeel -a org.ekklesia.classroom.desktop
// --resetLayout` rebuilds the whole desktop from this file. That is the
// classroom's recovery path for a damaged shell, and it is Plasma's own
// mechanism rather than something written here.
//
// One full-width bar along the bottom. Left is auxiliary, the middle is
// applications, the right is the small amount of status a teacher needs.
// Nothing else is on the screen.

// WHICH APPLICATIONS THIS DEVICE OFFERS.
//
// classroom-desktop-layout rewrites the lines between the markers to
// match device.conf and this machine's hardware, and nothing else in
// this file. Each application is its own line because each is its own
// setting: a laptop taking children's church needs Wonder Ink and a tower
// used for Bible study does not, so the shape of the machine is never
// allowed to decide what it is for.
//
// The first three are true here, which is what an existing classroom must
// come up as. PRESENTATIONS is false, which is what an existing classroom
// must come up as too: no room has ever had it, and an upgrade may not
// put a button on a bar nobody asked for.
/* CLASSROOM-FEATURES-BEGIN */
var WONDERINK = true;
var DVD = true;
var PARENT_CALL = true;
var PRESENTATIONS = false;
/* CLASSROOM-FEATURES-END */

var WALLPAPER = "/usr/share/backgrounds/ekklesia/classroom-calm.png";

// Matches the 76px strip the classroom has always used, so muscle memory
// and the room's viewing distance both carry over.
var PANEL_HEIGHT = 76;

// The idle desktop: the wallpaper, and nothing on it.
var screens = desktops();
for (var i = 0; i < screens.length; i++) {
    var desktop = screens[i];
    desktop.wallpaperPlugin = "org.kde.image";
    desktop.currentConfigGroup = ["Wallpaper", "org.kde.image", "General"];
    desktop.writeConfig("Image", "file://" + WALLPAPER);
    desktop.writeConfig("SlidePaths", "");
    // 2 is "scaled and cropped": the landscape fills the display at any
    // aspect ratio without being stretched out of shape.
    desktop.writeConfig("FillMode", 2);
    desktop.reloadConfig();
}

var panel = new Panel();
panel.location = "bottom";
panel.height = PANEL_HEIGHT;
panel.hiding = "none";
panel.floating = false;
panel.lengthMode = "fill";
panel.alignment = "center";
panel.opacity = "adaptive";

// LEFT — auxiliary. Parent Call is not one of the room's applications and
// is deliberately not in the row with them.
// Quick Launch: a launcher, and only a launcher.
//
// Two other widgets were tried on a real panel. The Icon widget copies
// the desktop entry into the user's home and uses the copy, so an update
// could never change the icon or the command — it kept showing a bell out
// of a package that no longer contained one. A task manager reads
// /usr/share/applications live, which fixes that, but a task manager also
// shows every running window, so the auxiliary corner filled up with the
// lesson's tasks.
//
// Quick Launch reads the entry live and shows nothing but the button.
if (PARENT_CALL) {
    var parentCall = panel.addWidget("org.kde.plasma.quicklaunch");
    parentCall.currentConfigGroup = ["General"];
    // A file URL, not applications:. Quick Launch resolves the entry
    // itself and does not copy it, so the path is a live reference to
    // what the package installs.
    parentCall.writeConfig(
        "launcherUrls",
        "file:///usr/share/applications/ekklesia-parent-call.desktop"
    );
    parentCall.writeConfig("showLauncherNames", false);
    parentCall.writeConfig("enablePopup", false);
    parentCall.writeConfig("maxSectionCount", 1);
}

// HELP, beside Parent Call and not in the row with the applications.
//
// Every room gets it: the manual is the one thing that is never optional,
// because a teacher who needs it is by definition a teacher who does not
// know where to look. It shows only the pages for the features THIS
// device has — see classroom-manual — so the button means the same thing
// in every room while what it opens does not.
//
// On the left, with Parent Call, for the same reason Parent Call is
// there: it is not one of the room's applications, and putting it in the
// middle row would move buttons teachers reach for without looking.
var help = panel.addWidget("org.kde.plasma.quicklaunch");
help.currentConfigGroup = ["General"];
help.writeConfig(
    "launcherUrls",
    "file:///usr/share/applications/ekklesia-manual.desktop"
);
help.writeConfig("showLauncherNames", false);
help.writeConfig("enablePopup", false);
help.writeConfig("maxSectionCount", 1);

var leftGap = panel.addWidget("org.kde.plasma.panelspacer");
leftGap.currentConfigGroup = ["General"];
leftGap.writeConfig("expanding", true);

// CENTRE — the applications, and the whole of the running/minimised/active
// story. This applet is the reason the classroom stops writing a dock.
var tasks = panel.addWidget("org.kde.plasma.icontasks");
tasks.currentConfigGroup = ["General"];
// THE LAUNCHERS, IN ONE FIXED ORDER.
//
// The order is written here and nowhere else, so the same set of enabled
// applications produces the same bar on every machine in the church.
// Anything switched off is left out of the list rather than blanked, so
// the remaining launchers close up and there is never a gap where a
// disabled application used to be.
//
// The browser is always present. Wonder Ink and the disc player are
// answered above.
var launchers = [];

if (WONDERINK) {
    launchers.push("applications:ekklesia-wonderink.desktop");
}

launchers.push("applications:google-chrome.desktop");

if (DVD) {
    launchers.push("applications:ekklesia-dvd.desktop");
}

// LAST, AND THAT IS THE WHOLE REASON IT IS HERE.
//
// Every existing room has Wonder Ink, the browser and the disc player in
// that order, and teachers have been pressing them in that order for
// months. Appending keeps all three exactly where they are on every
// machine that upgrades; putting Presentations anywhere else in the row
// would move a button somebody reaches for without looking.
if (PRESENTATIONS) {
    launchers.push("applications:ekklesia-presentations.desktop");
}

tasks.writeConfig("launchers", launchers.join(","));

// THE ORDER STAYS PUT WHEN AN APPLICATION OPENS.
//
// 1 is "manually", and it has to be 1. This is not a preference; it is
// the only value at which the Icons-Only Task Manager keeps a running
// application in its pinned position.
//
// 0.2.4 set this to 0 to stop teachers dragging the launchers about, and
// that worked — and broke the order instead, which is the bug this
// replaces. Two lines of the stock applet explain the whole thing:
//
//   main.qml:153  hideActivatedLaunchers: tasks.iconsOnly || ...
//   main.qml:155  launchInPlace: tasks.iconsOnly && sortingStrategy === 1
//
// For an icons-only bar the first is ALWAYS true: the moment an
// application starts, its launcher is hidden. The second is what puts the
// running window back in the launcher's place — and only at 1. At 0 the
// launcher vanished and the window was appended after the others, so
// opening the browser moved it behind the disc player. Reproduced in the
// lab with a real Chrome window, and fixed by this line; both measured.
//
// The cost is that manual sorting is also the only mode in which
// MouseHandler.qml accepts a reordering drop, so a teacher can drag the
// launchers again within a session. There is no value that gives both,
// and no Kiosk key that separates them. classroom-desktop-reset rebuilds
// this bar from the package at every login, so a drag never outlives the
// session, and docs/testing.md records the trade rather than hiding it.
tasks.writeConfig("sortingStrategy", 1);
// Launchers stay together at the start of the row and running windows
// appear after them, so opening or closing an application cannot move a
// pinned icon. This is Plasma's default; it is written down because the
// classroom depends on it.
tasks.writeConfig("separateLaunchers", true);
// Every window gets its own button. Teachers should never have to open a
// group to find out that a second window exists.
tasks.writeConfig("groupingStrategy", 0);
tasks.writeConfig("showOnlyCurrentDesktop", false);
tasks.writeConfig("showOnlyCurrentActivity", false);
tasks.writeConfig("showOnlyCurrentScreen", false);
// Clicking a button always means "show me this", and never "hide it".
//
// This was measured before it was decided. Plasma 6.3 draws a minimised
// task and a task that is merely behind another window identically: no
// indicator for closed, a grey indicator for running, a teal one for
// active — three marks for four states. Rather than write a task manager
// that draws a fourth, the classroom removes the state. There is nothing
// on the idle desktop for a teacher to want to see, so minimising an
// application in this room has no purpose and only ever loses it.
//
// A window minimised some other way is still shown as running and comes
// back with one click, so it can never be lost even then.
tasks.writeConfig("minimizeActiveTaskOnClick", false);
tasks.writeConfig("fill", false);
tasks.writeConfig("maxStripes", 1);
tasks.writeConfig("indicateAudioStreams", false);
tasks.writeConfig("wheelEnabled", false);
tasks.writeConfig("middleClickAction", "NewInstance");
tasks.writeConfig("showToolTips", true);
tasks.writeConfig("iconSpacing", 2);

var rightGap = panel.addWidget("org.kde.plasma.panelspacer");
rightGap.currentConfigGroup = ["General"];
rightGap.writeConfig("expanding", true);

// RIGHT — status.
//
// Three ordinary applets straight on the bar, and no system tray around
// them. A tray is a container that discovers whatever is installed and
// then hides most of it behind an arrow; measured in the lab it collected
// battery, brightness, clipboard, keyboard layout, camera, vaults and
// screen management on a machine that has none of those to say anything
// about. Naming the four the classroom actually uses is both smaller and
// deterministic, and it leaves nothing for a teacher to expand.
panel.addWidget("org.kde.plasma.networkmanagement");

var volume = panel.addWidget("org.kde.plasma.volume");
volume.currentConfigGroup = ["General"];
// No chime when the volume changes. A classroom is often listening to
// something when somebody adjusts it, and a beep over a lesson is worse
// than no feedback at all — the on-screen display is the feedback, and it
// is in the look and feel package where a television can read it.
//
// Plasma 6 moved this setting out of the applet and into a global one,
// and the applet migrates a false written here into it on first run. So
// this is both the setting and the instruction to carry it across.
volume.writeConfig("volumeFeedback", false);
volume.writeConfig("volumeOsd", true);
volume.writeConfig("muteOsd", true);
volume.writeConfig("outputChangeOsd", true);
// A teacher pressing the volume key expects a step they can hear.
volume.writeConfig("volumeStep", 5);

panel.addWidget("org.kde.plasma.notifications");

var clock = panel.addWidget("org.kde.plasma.digitalclock");
clock.currentConfigGroup = ["Appearance"];
clock.writeConfig("showDate", true);
clock.writeConfig("dateFormat", "custom");
clock.writeConfig("customDateFormat", "ddd d MMM");
clock.writeConfig("showSeconds", 0);
clock.writeConfig("dateDisplayFormat", "BelowTime");
// Sized by the bar, not by a number written here.
//
// It used to be pinned at 15 points to stop it becoming the largest text
// in the room. On a 4K television that was a clock a teacher could not
// read from the back of the room, and it was the one thing in the
// classroom that did not follow UI_SCALE, because a point size written
// into a layout is the same point size at every scale. Plasma's own
// sizing follows the bar, and the bar follows the scale.
clock.writeConfig("autoFontAndSize", true);
clock.writeConfig("fontWeight", 500);