#!/usr/bin/env bash
# サーバー側で root として実行し、各ユーザーの Claude Code systemd user service を同期する
set -euo pipefail

APP_DIR="$(cd "$(dirname "$0")/.." && pwd)"
TEMPLATE_SRC="$APP_DIR/systemd/user/claude-code@.service"
SESSIONS_FILE="$APP_DIR/claude-code-sessions.txt"

# sessions.txt をパースして user -> repos のマップを構築
declare -A user_repos

while IFS= read -r line; do
    [[ "$line" =~ ^#.*$ || -z "$line" ]] && continue
    user="${line%%:*}"
    repo="${line#*:}"
    user_repos["$user"]+=" $repo"
done < "$SESSIONS_FILE"

for user in "${!user_repos[@]}"; do
    uid=$(id -u "$user" 2>/dev/null) || { echo "WARNING: user $user not found, skipping"; continue; }
    runtime_dir="/run/user/$uid"
    systemd_dir="/home/$user/.config/systemd/user"

    mkdir -p "$systemd_dir"
    chown "$user:$user" "$systemd_dir"

    # テンプレートを更新（差分があれば）
    if ! diff -q "$TEMPLATE_SRC" "$systemd_dir/claude-code@.service" >/dev/null 2>&1; then
        echo "[$user] Updating claude-code@.service template"
        cp "$TEMPLATE_SRC" "$systemd_dir/claude-code@.service"
        chown "$user:$user" "$systemd_dir/claude-code@.service"
        runuser -u "$user" -- env XDG_RUNTIME_DIR="$runtime_dir" DBUS_SESSION_BUS_ADDRESS="unix:path=$runtime_dir/bus" \
            systemctl --user daemon-reload
    fi

    # sessions.txt で指定されたリポジトリを enable & start
    desired=()
    for repo in ${user_repos[$user]}; do
        [[ -z "$repo" ]] && continue
        desired+=("$repo")
        repo_path="/home/$user/workspaces/repos/$repo"
        if [[ ! -d "$repo_path" ]]; then
            echo "[$user] WARNING: $repo_path not found, skipping $repo"
            continue
        fi
        runuser -u "$user" -- env XDG_RUNTIME_DIR="$runtime_dir" DBUS_SESSION_BUS_ADDRESS="unix:path=$runtime_dir/bus" \
            systemctl --user enable "claude-code@${repo}.service" 2>/dev/null || true
        if ! runuser -u "$user" -- env XDG_RUNTIME_DIR="$runtime_dir" DBUS_SESSION_BUS_ADDRESS="unix:path=$runtime_dir/bus" \
            systemctl --user is-active "claude-code@${repo}.service" >/dev/null 2>&1; then
            echo "[$user] Starting claude-code@${repo}.service"
            runuser -u "$user" -- env XDG_RUNTIME_DIR="$runtime_dir" DBUS_SESSION_BUS_ADDRESS="unix:path=$runtime_dir/bus" \
                systemctl --user start "claude-code@${repo}.service" || true
        fi
    done

    # sessions.txt にないが enabled になっているインスタンスを無効化
    while IFS= read -r unit; do
        instance="${unit#claude-code@}"
        instance="${instance%.service}"
        if ! printf '%s\n' "${desired[@]}" | grep -qx "$instance"; then
            echo "[$user] Disabling claude-code@${instance}.service (not in sessions.txt)"
            runuser -u "$user" -- env XDG_RUNTIME_DIR="$runtime_dir" DBUS_SESSION_BUS_ADDRESS="unix:path=$runtime_dir/bus" \
                systemctl --user disable --now "claude-code@${instance}.service" || true
        fi
    done < <(runuser -u "$user" -- env XDG_RUNTIME_DIR="$runtime_dir" DBUS_SESSION_BUS_ADDRESS="unix:path=$runtime_dir/bus" \
        systemctl --user list-unit-files --plain --no-legend 'claude-code@*.service' 2>/dev/null \
        | awk '$2 == "enabled" {print $1}')
done

echo "Claude Code session sync complete."