#!/usr/bin/env bash
# MTGA Assistant installer for Linux.
#
#   ./install.sh              install or update (run it again after pulling a newer version)
#   ./install.sh --yes        same, answering "yes" to every question
#   ./install.sh --uninstall  remove the app, launcher and icons (history and settings are kept)
#
# It installs the app into its own Python environment (no root needed), adds a launcher
# (.desktop file) and icons, optionally starts it at login, and launches it.

set -euo pipefail

APP_ID="mtga-assistant"
APP_NAME="MTGA Assistant"
MIN_PY_MINOR=12   # Python 3.12+

PROJECT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
DATA_HOME="${XDG_DATA_HOME:-$HOME/.local/share}"
CONFIG_HOME="${XDG_CONFIG_HOME:-$HOME/.config}"
APP_DIR="$DATA_HOME/$APP_ID/app"          # the app's Python environment
BIN="$APP_DIR/bin/$APP_ID"
DESKTOP_FILE="$DATA_HOME/applications/$APP_ID.desktop"
ICON_THEME_DIR="$DATA_HOME/icons/hicolor"
ICON_SIZES=(32 48 64 128 256)
AUTOSTART_FILE="$CONFIG_HOME/autostart/$APP_ID.desktop"

ASSUME_YES=0
UNINSTALL=0
for arg in "$@"; do
    case "$arg" in
        -y|--yes) ASSUME_YES=1 ;;
        --uninstall) UNINSTALL=1 ;;
        -h|--help) sed -n '2,9p' "$0" | sed 's/^# \{0,1\}//'; exit 0 ;;
        *) echo "Unknown option: $arg (see --help)" >&2; exit 2 ;;
    esac
done

if [[ -t 1 ]]; then BOLD=$'\e[1m'; CYAN=$'\e[36m'; GREEN=$'\e[32m'; RED=$'\e[31m'; RESET=$'\e[0m'
else BOLD=""; CYAN=""; GREEN=""; RED=""; RESET=""; fi
step() { printf '\n%s==> %s%s\n' "$CYAN$BOLD" "$1" "$RESET"; }
info() { printf '    %s\n' "$1"; }
fail() { printf '\n%sERROR:%s %s\n' "$RED$BOLD" "$RESET" "$1" >&2; exit 1; }

ask() {  # ask "Question?" [default y|n] -> exit status 0 for yes
    local default="${2:-y}" hint answer
    [[ $default == y ]] && hint="[Y/n]" || hint="[y/N]"
    if (( ASSUME_YES )); then return 0; fi
    if [[ ! -t 0 ]]; then [[ $default == y ]]; return; fi
    read -r -p "    $1 $hint " answer || true
    answer="${answer:-$default}"
    [[ ${answer,,} == y* ]]
}

app_running() { pgrep -u "$(id -u)" -f "(bin/$APP_ID|-m mtga_assistant)( |$)" >/dev/null 2>&1; }

refresh_desktop_caches() {
    command -v update-desktop-database >/dev/null && update-desktop-database -q "$DATA_HOME/applications" || true
    command -v gtk-update-icon-cache >/dev/null && gtk-update-icon-cache -q -t "$ICON_THEME_DIR" 2>/dev/null || true
}

# --- uninstall ------------------------------------------------------------------------------------

if (( UNINSTALL )); then
    step "Uninstalling $APP_NAME"
    if app_running && ask "$APP_NAME is running. Quit it?"; then
        pkill -u "$(id -u)" -f "(bin/$APP_ID|-m mtga_assistant)( |$)" || true
    fi
    rm -rf "$APP_DIR"
    rm -f "$DESKTOP_FILE" "$AUTOSTART_FILE"
    for size in "${ICON_SIZES[@]}"; do rm -f "$ICON_THEME_DIR/${size}x${size}/apps/$APP_ID.png"; done
    refresh_desktop_caches
    info "Removed the app, its launcher, icons and login item."
    info "Your game history and settings are still in $DATA_HOME/$APP_ID and $CONFIG_HOME/$APP_ID;"
    info "delete those folders too to remove everything."
    exit 0
fi

printf '%s%s installer%s\n' "$GREEN$BOLD" "$APP_NAME" "$RESET"
info "Project folder: $PROJECT_DIR"

# --- 1. Python --------------------------------------------------------------------------------------

python_ok() {  # python_ok CMD -> prints version and succeeds if CMD is Python >= 3.MIN_PY_MINOR
    "$1" -c "import sys; assert sys.version_info >= (3, $MIN_PY_MINOR); print('%d.%d' % sys.version_info[:2])" 2>/dev/null
}

find_python() {
    local cmd
    for cmd in python3 python3.14 python3.13 python3.12 python; do
        if command -v "$cmd" >/dev/null && python_ok "$cmd" >/dev/null; then
            command -v "$cmd"; return 0
        fi
    done
    return 1
}

distro_install_hint() {  # prints a package-manager command for $1 (a space-separated package list per family)
    local id_like=""
    if [[ -r /etc/os-release ]]; then
        # shellcheck disable=SC1091
        id_like="$(. /etc/os-release; echo "${ID:-} ${ID_LIKE:-}")"
    fi
    case " $id_like " in
        *" arch "*)                    echo "sudo pacman -S --needed $1" ;;
        *" debian "*|*" ubuntu "*)     echo "sudo apt install $2" ;;
        *" fedora "*|*" rhel "*)       echo "sudo dnf install $3" ;;
        *" suse "*|*" opensuse "*)     echo "sudo zypper install $4" ;;
        *)                             echo "" ;;
    esac
}

step "Checking for Python 3.$MIN_PY_MINOR or newer"
if ! PYTHON="$(find_python)"; then
    cmd="$(distro_install_hint "python" "python3 python3-venv" "python3" "python3")"
    info "Python 3.$MIN_PY_MINOR+ was not found."
    if [[ -n $cmd ]] && ask "Install it now with: $cmd ?"; then
        $cmd
        PYTHON="$(find_python)" || fail "Python still isn't available after installing."
    else
        fail "Install Python 3.$MIN_PY_MINOR or newer${cmd:+ (e.g. $cmd)}, then run this script again."
    fi
fi
info "Using Python $(python_ok "$PYTHON") ($PYTHON)"

# --- 2. App environment and dependencies -------------------------------------------------------------

step "Installing $APP_NAME and its dependencies (first run downloads ~100 MB)"
if [[ ! -x $APP_DIR/bin/python ]]; then
    mkdir -p "$(dirname "$APP_DIR")"
    if ! "$PYTHON" -m venv "$APP_DIR" 2>/dev/null; then
        rm -rf "$APP_DIR"
        cmd="$(distro_install_hint "python" "python3-venv" "python3" "python3")"
        fail "Couldn't create a Python environment (the 'venv' module is missing).${cmd:+ Install it with: $cmd}"
    fi
fi
"$APP_DIR/bin/python" -m pip install --disable-pip-version-check --quiet --upgrade pip
"$APP_DIR/bin/python" -m pip install --disable-pip-version-check --quiet --upgrade "$PROJECT_DIR" \
    || fail "Installing the app failed (see the messages above)."
# The version number doesn't change between updates, so make sure the new code replaces the old.
"$APP_DIR/bin/python" -m pip install --disable-pip-version-check --quiet --force-reinstall --no-deps "$PROJECT_DIR" \
    || fail "Updating the app failed (see the messages above)."
info "Installed into $APP_DIR"

# --- 3. Qt system libraries ---------------------------------------------------------------------------

step "Checking that Qt can start"
if ! qt_error="$(QT_QPA_PLATFORM=offscreen "$APP_DIR/bin/python" -c \
        'from PySide6.QtWidgets import QApplication; QApplication([])' 2>&1)"; then
    info "Qt failed to load:"
    printf '%s\n' "$qt_error" | tail -n 3 | sed 's/^/      /'
    cmd="$(distro_install_hint "libxkbcommon libglvnd fontconfig wayland xcb-util-cursor" \
        "libegl1 libgl1 libxkbcommon0 libfontconfig1 libwayland-client0 libxcb-cursor0" \
        "libglvnd-egl libxkbcommon fontconfig libwayland-client xcb-util-cursor" \
        "libEGL1 libxkbcommon0 fontconfig libwayland-client0 libxcb-cursor0")"
    fail "Some system libraries Qt needs are missing.${cmd:+ Try: $cmd}"
fi
info "Qt loads fine."

# --- 4. Icons and launcher ------------------------------------------------------------------------------

step "Installing icons and the launcher"
QT_QPA_PLATFORM=offscreen "$APP_DIR/bin/python" - "$PROJECT_DIR/images/mtga-assistant-icon.png" \
    "$ICON_THEME_DIR" "$APP_ID" "${ICON_SIZES[@]}" <<'PY'
import sys
from pathlib import Path
from PySide6.QtCore import Qt
from PySide6.QtGui import QGuiApplication, QImage

src, theme_dir, app_id, *sizes = sys.argv[1:]
app = QGuiApplication([])
img = QImage(src)
if img.isNull():
    sys.exit(f"can't read {src}")
for size in map(int, sizes):
    out = Path(theme_dir) / f"{size}x{size}" / "apps" / f"{app_id}.png"
    out.parent.mkdir(parents=True, exist_ok=True)
    img.scaled(size, size, Qt.AspectRatioMode.KeepAspectRatio,
               Qt.TransformationMode.SmoothTransformation).save(str(out))
PY

mkdir -p "$(dirname "$DESKTOP_FILE")"
cat > "$DESKTOP_FILE" <<EOF
[Desktop Entry]
Type=Application
Name=$APP_NAME
GenericName=MTG Arena Tracker
Comment=Deck and game tracker for Magic: The Gathering Arena
Exec="$BIN" --background
Icon=$APP_ID
Terminal=false
Categories=Game;
Keywords=magic;mtg;arena;mtga;tracker;deck;
StartupWMClass=$APP_ID
EOF
if command -v desktop-file-validate >/dev/null && ! desktop-file-validate "$DESKTOP_FILE"; then
    fail "The generated launcher failed validation: $DESKTOP_FILE"
fi
refresh_desktop_caches
info "Launcher: $DESKTOP_FILE"
info "Icons:    $ICON_THEME_DIR/<size>/apps/$APP_ID.png"

# --- 5. Start at login, launch ---------------------------------------------------------------------------

step "Start at login"
info "Running in the background lets it record every game and pop up when MTGA starts."
if ask "Start $APP_NAME hidden when you log in?"; then
    "$APP_DIR/bin/python" -c "from mtga_assistant.background import set_autostart; set_autostart(True)"
    info "Added $AUTOSTART_FILE (change it later in the app: menu -> Start at login)."
else
    "$APP_DIR/bin/python" -c "from mtga_assistant.background import set_autostart; set_autostart(False)"
    info "Skipped."
fi

printf '\n%s%s is installed.%s\n' "$GREEN$BOLD" "$APP_NAME" "$RESET"
info "Remember to enable MTGA's detailed logs: Options -> Account -> Detailed Logs (Plugin Support)."
info "To update, run ./install.sh again; to remove, ./install.sh --uninstall"

if app_running; then
    info "$APP_NAME is already running; restart it (tray icon -> Quit, then start it again) to use this version."
elif ask "Start $APP_NAME now?"; then
    nohup "$BIN" >/dev/null 2>&1 &
    disown || true
fi