#!/bin/bash
# plymouth.sh — Plymouth boot splash installer
#
# Installs the M-Archy Plymouth theme: the magenta skull-monitor logo centred
# on a dark background, with the latest 3 boot-log lines polled underneath it
# as plain text (no spinner).
#
# SVG NOTE: Plymouth's image loader (ply-image) is PNG-only — it links against
# libpng and has no SVG or gdk-pixbuf dependency.  The ply-image.h header is
# even commented "png file loader".  bg-skull.svg must be converted to PNG with
# rsvg-convert (higher fidelity than ImageMagick for SVG) before deployment.
#
# Logo resolution order:
#   1. $PLYMOUTH_LOGO_SRC env var — caller-supplied custom image (PNG or SVG)
#   2. $DOTFILES_DIR/resources/bg-skull.svg  — repo copy, always present
#   3. /root/installer/resources/bg-skull.svg — archiso embedded copy
#
# PNG inputs are used directly; SVG inputs are converted via rsvg-convert.
#
# Steps:
#   1. Install plymouth (extra repo)
#   2. Install librsvg (rsvg-convert) if logo is SVG
#   3. Produce logo.png (600 px wide) from the resolved source
#   4. Write the m-archy theme (.plymouth descriptor + .script animation)
#   5. Register with plymouth-set-default-theme
#   6. Inject plymouth / sd-plymouth hook into /etc/mkinitcpio.conf
#   7. Add 'quiet splash' to GRUB_CMDLINE_LINUX_DEFAULT
#   8. Regenerate GRUB config and initramfs

set -euo pipefail
source "$(dirname "${BASH_SOURCE[0]}")/../../lib/logging.sh"

THEME_DIR="/usr/share/plymouth/themes/m-archy"
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
# apps/ → optional-Modules → modules → setup → repo root (four levels up).
DOTFILES_DIR="$(cd "$SCRIPT_DIR/../../../.." && pwd)"

# Resolve logo source — env var takes priority, then bundled SVG
LOGO_SRC="${PLYMOUTH_LOGO_SRC:-}"
if [[ -z "$LOGO_SRC" ]]; then
    for _candidate in \
        "$DOTFILES_DIR/resources/bg-skull.svg" \
        "/root/installer/resources/bg-skull.svg"
    do
        if [[ -f "$_candidate" ]]; then
            LOGO_SRC="$_candidate"
            break
        fi
    done
fi

# ── Install Plymouth ──────────────────────────────────────────────────────────
log "Installing Plymouth..."
sudo pacman -S --noconfirm --needed plymouth

# ── Produce logo.png ──────────────────────────────────────────────────────────
TMP_LOGO="$(mktemp /tmp/plymouth-logo.XXXXXX.png)"
trap 'rm -f "$TMP_LOGO"' EXIT

if [[ -z "$LOGO_SRC" ]]; then
    warn "No logo source found — using transparent placeholder."
    if ! command -v convert &>/dev/null; then
        log "Installing imagemagick (placeholder generation)..."
        sudo pacman -S --noconfirm --needed imagemagick
    fi
    convert -size 600x600 xc:transparent "$TMP_LOGO"
elif [[ "${LOGO_SRC,,}" == *.png ]]; then
    log "Using PNG directly: $LOGO_SRC"
    cp "$LOGO_SRC" "$TMP_LOGO"
else
    # SVG (or unknown) — convert via rsvg-convert for best fidelity
    if ! command -v rsvg-convert &>/dev/null; then
        log "Installing librsvg (rsvg-convert) for SVG→PNG conversion..."
        sudo pacman -S --noconfirm --needed librsvg
    fi
    # Render at 600 px wide — the skull is centred (not full-screen), and the
    # Plymouth script scales it down to a fraction of the display height, so we
    # only need enough resolution to stay crisp on high-DPI panels.
    log "Converting $LOGO_SRC → PNG (600 px wide)..."
    rsvg-convert -w 600 "$LOGO_SRC" -o "$TMP_LOGO"
fi

# ── Install theme files ───────────────────────────────────────────────────────
log "Installing M-Archy Plymouth theme..."
sudo mkdir -p "$THEME_DIR"
sudo cp "$TMP_LOGO" "$THEME_DIR/logo.png"

sudo tee "$THEME_DIR/m-archy.plymouth" > /dev/null <<'EOF'
[Plymouth Theme]
Name=M-Archy
Description=M-Archy boot splash — centred skull logo with a boot-log tail
ModuleName=script

[script]
ImageDir=/usr/share/plymouth/themes/m-archy
ScriptFile=/usr/share/plymouth/themes/m-archy/m-archy.script
EOF

sudo tee "$THEME_DIR/m-archy.script" > /dev/null <<'EOF'
# M-Archy Plymouth splash — centred skull logo + latest 3 boot-log lines.

Window.SetBackgroundTopColor    (0.10, 0.10, 0.10);
Window.SetBackgroundBottomColor (0.07, 0.07, 0.07);

screen_width  = Window.GetWidth ();
screen_height = Window.GetHeight ();

# ── Skull logo, centred ───────────────────────────────────────────────────────
# logo.png is the tight skull-monitor artwork (roughly square). Scale it to a
# fraction of the screen height, preserving aspect ratio, then centre it and
# nudge it up a little so the log lines below have room to breathe.
logo.image = Image ("logo.png");
target_h   = screen_height * 0.42;
scale      = target_h / logo.image.GetHeight ();
scaled     = logo.image.Scale (logo.image.GetWidth () * scale, target_h);

logo.sprite = Sprite (scaled);
logo.sprite.SetX ((screen_width  - scaled.GetWidth ())  / 2);
logo.sprite.SetY ((screen_height - scaled.GetHeight ()) / 2 - screen_height * 0.08);
logo.sprite.SetZ (10);

# ── Boot-log tail — latest 3 lines ────────────────────────────────────────────
# A rolling buffer of the three most recent status/message strings Plymouth
# hands us, drawn as centred text beneath the logo. The newest line is the
# brightest; older lines fade back.
num_lines = 3;
line_gap  = 26;                                # px between successive baselines
text_top  = Math.Int (screen_height * 0.72);   # y of the oldest (top) line

for (i = 0; i < num_lines; i++) {
    log_line[i]   = "";
    log_sprite[i] = Sprite ();
    log_sprite[i].SetZ (20);
}

fun draw_lines () {
    for (i = 0; i < num_lines; i++) {
        # Empty slots (before the buffer fills) stay hidden — Image.Text ("")
        # is unreliable across Plymouth versions, so never render it.
        if (log_line[i] == "") {
            log_sprite[i].SetOpacity (0);
        } else {
            shade = 0.40 + 0.25 * i;           # 0.40, 0.65, 0.90 top→bottom
            image = Image.Text (log_line[i], shade, shade, shade);
            log_sprite[i].SetImage (image);
            log_sprite[i].SetX ((screen_width - image.GetWidth ()) / 2);
            log_sprite[i].SetY (text_top + i * line_gap);
            log_sprite[i].SetOpacity (1);
        }
    }
}

fun push_line (text) {
    # Scroll the buffer up by one line and append the newcomer at the bottom.
    for (i = 0; i < num_lines - 1; i++) {
        log_line[i] = log_line[i + 1];
    }
    log_line[num_lines - 1] = text;
    draw_lines ();
}

# Both callbacks feed the same tail: systemd unit progress arrives via the
# status function, explicit `plymouth display-message` strings via the message
# function.
Plymouth.SetUpdateStatusFunction   (fun (status) { push_line (status); });
Plymouth.SetDisplayMessageFunction (fun (text)   { push_line (text);   });
EOF

# ── Register theme ────────────────────────────────────────────────────────────
log "Registering m-archy as default Plymouth theme..."
sudo plymouth-set-default-theme m-archy

# ── mkinitcpio: inject Plymouth hook ─────────────────────────────────────────
log "Adding Plymouth hook to /etc/mkinitcpio.conf..."
if grep -q '\bplymouth\b\|sd-plymouth' /etc/mkinitcpio.conf; then
    skip "Plymouth hook already present in mkinitcpio.conf"
else
    # systemd hook → sd-plymouth goes after systemd
    # traditional udev hook → plymouth goes after udev
    if grep -qE 'HOOKS=\([^)]*\bsystemd\b' /etc/mkinitcpio.conf; then
        sudo sed -Ei 's/(\bsystemd\b)( |\))/\1 sd-plymouth\2/' /etc/mkinitcpio.conf
        log "Injected sd-plymouth hook after systemd"
    else
        sudo sed -Ei 's/(\budev\b)( |\))/\1 plymouth\2/' /etc/mkinitcpio.conf
        log "Injected plymouth hook after udev"
    fi

    if ! grep -q '\bplymouth\b\|sd-plymouth' /etc/mkinitcpio.conf; then
        warn "Could not auto-inject Plymouth hook."
        warn "Manually add 'plymouth' after 'udev' in /etc/mkinitcpio.conf."
    fi
fi

# ── GRUB: add quiet splash ────────────────────────────────────────────────────
GRUB_CONF="/etc/default/grub"
if [[ -f "$GRUB_CONF" ]]; then
    if grep -q '\bsplash\b' "$GRUB_CONF"; then
        skip "'splash' already present in $GRUB_CONF"
    else
        log "Adding 'quiet splash' to GRUB_CMDLINE_LINUX_DEFAULT..."
        sudo sed -i 's/^GRUB_CMDLINE_LINUX_DEFAULT="\(.*\)"/GRUB_CMDLINE_LINUX_DEFAULT="\1 quiet splash"/' "$GRUB_CONF"
        sudo sed -i 's/quiet quiet/quiet/g' "$GRUB_CONF"
    fi
    log "Regenerating GRUB config..."
    sudo grub-mkconfig -o /boot/grub/grub.cfg
else
    warn "/etc/default/grub not found."
    warn "If using systemd-boot, add 'quiet splash' to your loader entry manually."
fi

# ── Rebuild initramfs ─────────────────────────────────────────────────────────
log "Rebuilding initramfs (this bakes the theme into the initrd)..."
sudo mkinitcpio -P

log "Plymouth m-archy theme installed. Reboot to see the splash screen."