#!/usr/bin/env bash
set -Eeuo pipefail

readonly PROJECT="niri-beyond-glass"
readonly NIRI_TAG="v26.04"
readonly XWS_TAG="v0.8.2"
readonly RUST_TOOLCHAIN="1.85.1"
readonly ARCHIVE_URL="https://git.k1412.top/wuyang/niri-beyond-glass/archive/main.tar.gz"

wallpaper=""
config_only=0
dry_run=0
rebuild=0
source_dir="${NBG_SOURCE_DIR:-}"
tmp_dir=""

usage() {
    cat <<'EOF'
用法：install.sh [选项]

  --wallpaper PATH  使用指定的静态壁纸
  --config-only     只更新配置，不安装/编译软件
  --rebuild         强制重新编译 Niri 和 Xwayland Satellite
  --dry-run         显示将执行的主要步骤，不修改系统
  -h, --help        显示帮助
EOF
}

log() {
    printf '\033[1;36m[Niri]\033[0m %s\n' "$*"
}

die() {
    printf '\033[1;31m错误：\033[0m %s\n' "$*" >&2
    exit 1
}

run() {
    if (( dry_run )); then
        printf '+'
        printf ' %q' "$@"
        printf '\n'
    else
        "$@"
    fi
}

cleanup() {
    [[ -n "$tmp_dir" && -d "$tmp_dir" ]] && rm -rf "$tmp_dir"
}
trap cleanup EXIT

while (($#)); do
    case "$1" in
        --wallpaper)
            (($# >= 2)) || die "--wallpaper 缺少路径"
            wallpaper="$2"
            shift 2
            ;;
        --config-only)
            config_only=1
            shift
            ;;
        --rebuild)
            rebuild=1
            shift
            ;;
        --dry-run)
            dry_run=1
            shift
            ;;
        -h|--help)
            usage
            exit 0
            ;;
        *)
            die "未知参数：$1"
            ;;
    esac
done

[[ ${EUID:-$(id -u)} -ne 0 ]] || die "请用普通用户运行，脚本会在需要时调用 sudo。"
[[ -z "$wallpaper" || -f "$wallpaper" ]] || die "壁纸不存在：$wallpaper"

if [[ -r /etc/os-release ]]; then
    # shellcheck disable=SC1091
    . /etc/os-release
else
    die "无法识别操作系统。"
fi

if [[ "${ID:-}" != "ubuntu" || "${VERSION_ID:-}" != "24.04" ]]; then
    die "只支持 Ubuntu 24.04；当前是 ${PRETTY_NAME:-未知系统}。"
fi

case "$(uname -m)" in
    x86_64|aarch64) ;;
    *) die "目前只支持 x86_64 和 aarch64。" ;;
esac

fetch_source() {
    if [[ -n "$source_dir" ]]; then
        [[ -f "$source_dir/config/niri/config.kdl" ]] || die "NBG_SOURCE_DIR 不是有效源码目录。"
        return
    fi

    tmp_dir="$(mktemp -d)"
    log "下载配置仓库"
    curl -fL --retry 3 "$ARCHIVE_URL" -o "$tmp_dir/source.tar.gz"
    mkdir -p "$tmp_dir/source"
    tar -xzf "$tmp_dir/source.tar.gz" -C "$tmp_dir/source" --strip-components=1
    source_dir="$tmp_dir/source"
}

install_packages() {
    log "安装 Ubuntu 24.04 依赖"
    run sudo apt-get update
    run sudo env DEBIAN_FRONTEND=noninteractive apt-get install -y \
        build-essential clang git curl ca-certificates pkg-config \
        meson ninja-build cmake \
        libudev-dev libgbm-dev libxkbcommon-dev libegl1-mesa-dev \
        libwayland-dev libinput-dev libdbus-1-dev libsystemd-dev \
        libseat-dev libpipewire-0.3-dev libpango1.0-dev \
        libdisplay-info-dev libcairo2-dev libglib2.0-dev \
        libxcb1-dev libxcb-composite0-dev libxcb-randr0-dev \
        libxcb-res0-dev libxcb-xfixes0-dev libxcb-cursor-dev \
        xwayland xdg-desktop-portal-gnome xdg-desktop-portal-gtk \
        alacritty fuzzel waybar swaybg swaylock swayidle mako-notifier \
        nautilus policykit-1-gnome pipewire-pulse wireplumber \
        brightnessctl playerctl grim slurp wl-clipboard wlogout \
        fonts-noto-core fonts-noto-cjk fonts-noto-color-emoji fonts-font-awesome
}

install_rust() {
    export RUSTUP_HOME="${XDG_DATA_HOME:-$HOME/.local/share}/$PROJECT/rustup"
    export CARGO_HOME="${XDG_DATA_HOME:-$HOME/.local/share}/$PROJECT/cargo"
    export PATH="$CARGO_HOME/bin:$PATH"

    if [[ ! -x "$CARGO_HOME/bin/rustup" ]]; then
        log "安装隔离的 Rust $RUST_TOOLCHAIN 工具链"
        if (( dry_run )); then
            printf '+ curl https://sh.rustup.rs | sh -s -- -y --no-modify-path --profile minimal --default-toolchain %q\n' "$RUST_TOOLCHAIN"
            return
        fi
        curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs |
            sh -s -- -y --no-modify-path --profile minimal --default-toolchain "$RUST_TOOLCHAIN"
    else
        run "$CARGO_HOME/bin/rustup" toolchain install "$RUST_TOOLCHAIN" --profile minimal
        run "$CARGO_HOME/bin/rustup" default "$RUST_TOOLCHAIN"
    fi
}

version_ge() {
    [[ "$(printf '%s\n%s\n' "$2" "$1" | sort -V | head -n1)" == "$2" ]]
}

install_libdisplay_info() {
    local installed=""
    installed="$(pkg-config --modversion libdisplay-info 2>/dev/null || true)"
    if [[ -n "$installed" ]] && version_ge "$installed" "0.3.0"; then
        return
    fi

    log "编译 libdisplay-info 0.3.0（Ubuntu 24.04 自带版本较旧）"
    local build_root="${XDG_CACHE_HOME:-$HOME/.cache}/$PROJECT/build"
    local src="$build_root/libdisplay-info"
    run mkdir -p "$build_root"
    if [[ ! -d "$src/.git" ]]; then
        run git clone --depth 1 --branch 0.3.0 \
            https://gitlab.freedesktop.org/emersion/libdisplay-info.git "$src"
    fi
    run meson setup "$src/build" "$src" --prefix=/usr/local --buildtype=release --wipe
    run ninja -C "$src/build"
    run sudo ninja -C "$src/build" install
    run sudo ldconfig
}

install_niri() {
    local current=""
    current="$(niri --version 2>/dev/null || true)"
    if (( ! rebuild )) && [[ "$current" == *"26.4"* || "$current" == *"26.04"* ]]; then
        log "已安装兼容的 $current，跳过编译"
        return
    fi

    log "编译 Niri $NIRI_TAG"
    local build_root="${XDG_CACHE_HOME:-$HOME/.cache}/$PROJECT/build"
    local src="$build_root/niri"
    run mkdir -p "$build_root"
    if [[ ! -d "$src/.git" ]]; then
        run git clone --depth 1 --branch "$NIRI_TAG" https://github.com/niri-wm/niri.git "$src"
    else
        run git -C "$src" fetch --depth 1 origin "refs/tags/$NIRI_TAG:refs/tags/$NIRI_TAG"
        run git -C "$src" checkout -f "$NIRI_TAG"
    fi
    run cargo build --manifest-path "$src/Cargo.toml" --release --locked

    run sudo install -Dm755 "$src/target/release/niri" /usr/local/bin/niri
    run sudo install -Dm755 "$src/resources/niri-session" /usr/local/bin/niri-session
    run sudo install -Dm644 "$src/resources/niri.service" /usr/local/lib/systemd/user/niri.service
    run sudo install -Dm644 "$src/resources/niri-shutdown.target" /usr/local/lib/systemd/user/niri-shutdown.target
    run sudo install -Dm644 "$src/resources/niri.desktop" /usr/local/share/wayland-sessions/niri.desktop
    run sudo install -Dm644 "$src/resources/niri-portals.conf" /usr/local/share/xdg-desktop-portal/niri-portals.conf
}

install_xwayland_satellite() {
    if (( ! rebuild )) && command -v xwayland-satellite >/dev/null 2>&1; then
        return
    fi

    log "编译 Xwayland Satellite $XWS_TAG"
    local build_root="${XDG_CACHE_HOME:-$HOME/.cache}/$PROJECT/build"
    local src="$build_root/xwayland-satellite"
    run mkdir -p "$build_root"
    if [[ ! -d "$src/.git" ]]; then
        run git clone --depth 1 --branch "$XWS_TAG" \
            https://github.com/Supreeeme/xwayland-satellite.git "$src"
    else
        run git -C "$src" fetch --depth 1 origin "refs/tags/$XWS_TAG:refs/tags/$XWS_TAG"
        run git -C "$src" checkout -f "$XWS_TAG"
    fi
    run cargo build --manifest-path "$src/Cargo.toml" --release --locked
    run sudo install -Dm755 "$src/target/release/xwayland-satellite" /usr/local/bin/xwayland-satellite
}

backup_and_install_config() {
    local config_home="${XDG_CONFIG_HOME:-$HOME/.config}"
    local state_home="${XDG_STATE_HOME:-$HOME/.local/state}"
    local stamp
    stamp="$(date +%Y%m%d-%H%M%S)"
    local backup="$state_home/$PROJECT/backups/$stamp/config"
    local names=(niri waybar fuzzel mako swaylock niri-beyond-glass)

    log "备份并安装用户配置"
    run mkdir -p "$backup"
    local name
    for name in "${names[@]}"; do
        if [[ -e "$config_home/$name" ]]; then
            run cp -a "$config_home/$name" "$backup/$name"
        fi
    done

    run mkdir -p \
        "$config_home/niri" \
        "$config_home/waybar" \
        "$config_home/fuzzel" \
        "$config_home/mako" \
        "$config_home/swaylock" \
        "$config_home/niri-beyond-glass" \
        "$HOME/.local/bin" \
        "$HOME/Pictures/Screenshots"

    run install -m644 "$source_dir/config/niri/config.kdl" "$config_home/niri/config.kdl"
    run install -m644 "$source_dir/config/waybar/config.jsonc" "$config_home/waybar/config.jsonc"
    run install -m644 "$source_dir/config/waybar/style.css" "$config_home/waybar/style.css"
    run install -m644 "$source_dir/config/fuzzel/fuzzel.ini" "$config_home/fuzzel/fuzzel.ini"
    run install -m644 "$source_dir/config/mako/config" "$config_home/mako/config"
    run install -m644 "$source_dir/config/swaylock/config" "$config_home/swaylock/config"
    run install -m755 "$source_dir/scripts/niri-beyond-wallpaper" "$HOME/.local/bin/niri-beyond-wallpaper"

    select_wallpaper "$config_home/niri-beyond-glass/wallpaper"
}

select_wallpaper() {
    local state_file="$1"
    local selected="$wallpaper"

    if [[ -z "$selected" ]]; then
        local candidates=(
            /usr/share/backgrounds/warty-final-ubuntu.png
            /usr/share/backgrounds/ubuntu-default-greyscale-wallpaper.png
        )
        local candidate
        for candidate in "${candidates[@]}"; do
            if [[ -f "$candidate" ]]; then
                selected="$candidate"
                break
            fi
        done
    fi

    if [[ -z "$selected" ]]; then
        selected="$(find /usr/share/backgrounds -maxdepth 2 -type f \
            \( -iname '*.jpg' -o -iname '*.jpeg' -o -iname '*.png' \) \
            -print -quit 2>/dev/null || true)"
    fi

    if (( dry_run )); then
        printf '+ write wallpaper path %q to %q\n' "$selected" "$state_file"
    else
        printf '%s\n' "$selected" > "$state_file"
    fi
}

validate_config() {
    if (( dry_run )); then
        printf '+ niri validate -c %q\n' "${XDG_CONFIG_HOME:-$HOME/.config}/niri/config.kdl"
        return
    fi
    command -v niri >/dev/null 2>&1 || die "找不到 niri，无法验证配置。"
    niri validate -c "${XDG_CONFIG_HOME:-$HOME/.config}/niri/config.kdl"
}

main() {
    fetch_source

    if (( ! config_only )); then
        install_packages
        install_rust
        install_libdisplay_info
        install_niri
        install_xwayland_satellite
    fi

    backup_and_install_config
    validate_config

    log "安装完成"
    printf '\n请注销，在 GDM 会话菜单中选择“Niri”后登录。\n'
    printf 'GNOME 和 GDM 均未被修改；快捷键说明：Super+Shift+/。\n'
}

main