#!/bin/bash
# services/authelia.sh — Authelia SSO + 2FA portal (forward-auth for Caddy).
# Ported from the authelia-setup repo / the monolith's working block.
# Part of the modular post-install system (sourced by setup.sh).

register_service authelia homelab "SSO + 2FA auth portal (Authelia)" 9091

install_authelia() {
    require_docker || return 1
    local AUTHELIA_DIR="$DOCKER_DIR/authelia"

    if [ "$DRY_RUN" = true ]; then
        echo "[DRY-RUN] Would set up Authelia:"
        echo "  • Create $AUTHELIA_DIR (config/secrets, data)"
        echo "  • Generate jwt/session/storage secrets + admin password hash"
        echo "  • Write docker-compose.yml, configuration.yml, users.yml, README.md"
        echo "  • Create the caddy_net network and add the forward-auth snippet to the Caddyfile"
        return 0
    fi

    # Don't clobber an existing install (it would regenerate secrets and break sessions).
    if [ -f "$AUTHELIA_DIR/docker-compose.yml" ]; then
        local RECONF=""
        echo "  ⚠ Authelia already exists at $AUTHELIA_DIR (secrets/users would be regenerated)."
        prompt_yn "  Reconfigure from scratch? (y/n):" "n" RECONF
        if [ "$RECONF" != "y" ] && [ "$RECONF" != "Y" ]; then
            echo "  Keeping existing Authelia. (Edit config/users.yml then: cd $AUTHELIA_DIR && docker compose restart authelia)"
            return 0
        fi
    fi

    log_info "Installing Authelia..."
    mkdir -p "$AUTHELIA_DIR/config/secrets" "$AUTHELIA_DIR/data"

    # ── Collect configuration ────────────────────────────────────────────────
    echo ""
    echo "  Authelia needs a few details to configure."
    echo ""
    local CADDY_NET="${SITE_CADDY_NET:-caddy_net}"
    local AUTHELIA_DOMAIN AUTHELIA_ADMIN_USER AUTHELIA_ADMIN_DISPLAY AUTHELIA_ADMIN_EMAIL
    local AUTHELIA_SMTP_HOST AUTHELIA_SMTP_PORT AUTHELIA_SMTP_USER AUTHELIA_SMTP_PASS AUTHELIA_TZ
    prompt_text "  Your domain (e.g., example.com):" "${SITE_DOMAIN:-example.com}" AUTHELIA_DOMAIN
    prompt_text "  Admin username:" "admin" AUTHELIA_ADMIN_USER
    prompt_text "  Admin display name:" "Administrator" AUTHELIA_ADMIN_DISPLAY
    prompt_text "  Admin email:" "admin@${AUTHELIA_DOMAIN}" AUTHELIA_ADMIN_EMAIL
    prompt_text "  SMTP server (e.g., smtp.migadu.com):" "smtp.migadu.com" AUTHELIA_SMTP_HOST
    prompt_text "  SMTP port:" "587" AUTHELIA_SMTP_PORT
    prompt_text "  SMTP username (full email):" "authelia@${AUTHELIA_DOMAIN}" AUTHELIA_SMTP_USER
    prompt_text "  SMTP password:" "" AUTHELIA_SMTP_PASS
    prompt_text "  Timezone (e.g., America/New_York):" "${SITE_TZ:-America/New_York}" AUTHELIA_TZ

    # ── Secrets ──────────────────────────────────────────────────────────────
    echo ""
    echo "  Generating secrets..."
    echo "$(openssl rand -hex 32)" > "$AUTHELIA_DIR/config/secrets/jwt_secret"
    echo "$(openssl rand -hex 32)" > "$AUTHELIA_DIR/config/secrets/session_secret"
    echo "$(openssl rand -hex 32)" > "$AUTHELIA_DIR/config/secrets/storage_secret"
    echo "$AUTHELIA_SMTP_PASS"     > "$AUTHELIA_DIR/config/secrets/smtp_password"
    chmod 600 "$AUTHELIA_DIR/config/secrets/"*
    echo "  ✓ Secrets generated"

    # ── Admin password hash ──────────────────────────────────────────────────
    echo ""
    local AUTHELIA_TEMP_PASS AUTHELIA_HASH
    prompt_text "  Temporary password for admin (users reset via email):" "TempPass2026!" AUTHELIA_TEMP_PASS
    echo "  Generating password hash..."
    AUTHELIA_HASH=$(docker run --rm authelia/authelia:4.39.20 \
        authelia crypto hash generate argon2 --password "$AUTHELIA_TEMP_PASS" 2>/dev/null \
        | grep -oP '(?<=Digest: ).*' || echo "REPLACE_WITH_HASH")
    if [ "$AUTHELIA_HASH" = "REPLACE_WITH_HASH" ]; then
        log_warning "Could not generate hash automatically. After install run:"
        echo "    docker run --rm authelia/authelia:4.39.20 authelia crypto hash generate argon2 --password 'yourpassword'"
        echo "    then update $AUTHELIA_DIR/config/users.yml"
    else
        echo "  ✓ Password hash generated"
    fi

    ensure_docker_dir_ownership "$AUTHELIA_DIR"
    cd "$AUTHELIA_DIR" || return 1

    # ── .env ─────────────────────────────────────────────────────────────────
    cat > .env << AUTHELIA_ENV
MY_DOMAIN=${AUTHELIA_DOMAIN}
SMTP_USER=${AUTHELIA_SMTP_USER}
DOCKER_MY_NETWORK=${CADDY_NET}
TZ=${AUTHELIA_TZ}
AUTHELIA_ENV

    # ── docker-compose.yml (quoted heredoc: ${SMTP_USER} resolved by compose/.env) ──
    cat > docker-compose.yml << 'AUTHELIA_COMPOSE'
name: authelia

services:
  authelia:
    image: authelia/authelia:4.39.20
    pull_policy: missing
    container_name: authelia
    user: "1000:1000"
    volumes:
      - ./config:/config
      - ./data:/data
    environment:
      - AUTHELIA_IDENTITY_VALIDATION_RESET_PASSWORD_JWT_SECRET_FILE=/config/secrets/jwt_secret
      - AUTHELIA_SESSION_SECRET_FILE=/config/secrets/session_secret
      - AUTHELIA_STORAGE_ENCRYPTION_KEY_FILE=/config/secrets/storage_secret
      - AUTHELIA_NOTIFIER_SMTP_PASSWORD_FILE=/config/secrets/smtp_password
      - AUTHELIA_NOTIFIER_SMTP_USERNAME=${SMTP_USER}
      - AUTHELIA_NOTIFIER_SMTP_SENDER=Authelia <${SMTP_USER}>
    expose:
      - 9091
    restart: unless-stopped
    networks:
      - caddy_net

networks:
  caddy_net:
    external: true
AUTHELIA_COMPOSE
    [ "$CADDY_NET" != "caddy_net" ] && sed -i "s/caddy_net/${CADDY_NET}/g" docker-compose.yml

    # ── configuration.yml ────────────────────────────────────────────────────
    cat > config/configuration.yml << AUTHELIA_CONFIG
---
# Authelia configuration. Secrets injected via AUTHELIA_* env vars in compose.
theme: dark

server:
  address: tcp://0.0.0.0:9091

log:
  level: info
  file_path: /data/authelia.log

totp:
  period: 30
  skew: 1

authentication_backend:
  file:
    path: /config/users.yml
    password:
      algorithm: argon2
      argon2:
        variant: argon2id
        iterations: 3
        memory: 65536
        parallelism: 4
        key_length: 32
        salt_length: 16

access_control:
  default_policy: deny
  rules:
    - domain: "*.${AUTHELIA_DOMAIN}"
      policy: two_factor

session:
  name: authelia_session
  expiration: 12h
  inactivity: 2h
  remember_me: 7d
  cookies:
    - domain: ${AUTHELIA_DOMAIN}
      authelia_url: https://auth.${AUTHELIA_DOMAIN}
      default_redirection_url: https://${AUTHELIA_DOMAIN}

storage:
  local:
    path: /data/db.sqlite3

notifier:
  disable_startup_check: false
  smtp:
    address: smtp://${AUTHELIA_SMTP_HOST}:${AUTHELIA_SMTP_PORT}
    timeout: 10s
    identifier: localhost
    subject: "[Authelia] {title}"
    startup_check_address: ${AUTHELIA_SMTP_USER}
    disable_require_tls: false
    disable_starttls: false
AUTHELIA_CONFIG

    # ── users.yml ────────────────────────────────────────────────────────────
    cat > config/users.yml << AUTHELIA_USERS
---
# Authelia users database
# Add users: copy a block, change username/email/displayname, restart authelia.
# Generate a hash: docker run --rm authelia/authelia:4.39.20 authelia crypto hash generate argon2 --password 'thepassword'
# Login with username (not email). Use "Forgot Password" to set a real password.

users:
  ${AUTHELIA_ADMIN_USER}:
    displayname: "${AUTHELIA_ADMIN_DISPLAY}"
    email: ${AUTHELIA_ADMIN_EMAIL}
    password: "${AUTHELIA_HASH}"
    groups:
      - admins
      - users
AUTHELIA_USERS

    chown -R 1000:1000 "$AUTHELIA_DIR/config" "$AUTHELIA_DIR/data"
    log_success "Authelia configured at $AUTHELIA_DIR"

    # ── Docker network ────────────────────────────────────────────────────────
    if ! docker network ls --format '{{.Name}}' | grep -q "^${CADDY_NET}$"; then
        docker network create "$CADDY_NET" >/dev/null 2>&1 && echo "  ✓ Created docker network ${CADDY_NET}" \
            || echo "  ⚠ Failed to create ${CADDY_NET}"
    else
        echo "  ✓ Docker network ${CADDY_NET} already exists"
    fi

    # ── Caddyfile forward-auth snippet + portal block ────────────────────────
    local CADDY_FILE="$DOCKER_DIR/caddy/Caddyfile"
    if [ -f "$CADDY_FILE" ]; then
        echo "  Configuring Caddy for Authelia..."
        if ! grep -q "(authelia)" "$CADDY_FILE"; then
            cp "$CADDY_FILE" "$CADDY_FILE.backup.$(date +%Y%m%d-%H%M%S)"
            { cat << 'SNIPPET_EOF'
# ── Authelia forward auth snippet ─────────────────────────────────────────────
(authelia) {
    forward_auth authelia:9091 {
        uri /api/authz/forward-auth
        copy_headers Remote-User Remote-Groups Remote-Name Remote-Email
    }
}

SNIPPET_EOF
              cat "$CADDY_FILE"; } > "$CADDY_FILE.tmp" && mv "$CADDY_FILE.tmp" "$CADDY_FILE"
            echo "  ✓ Authelia snippet added to Caddyfile"
        fi
        if ! grep -q "auth.${AUTHELIA_DOMAIN}" "$CADDY_FILE"; then
            cat >> "$CADDY_FILE" << CADDY_AUTH_BLOCK

# ── Authelia login portal ──────────────────────────────────────────────────────
auth.${AUTHELIA_DOMAIN} {
    reverse_proxy authelia:9091
    log {
        output file /var/log/caddy/auth.log
    }
}
CADDY_AUTH_BLOCK
            echo "  ✓ Authelia portal block added for auth.${AUTHELIA_DOMAIN}"
        fi
        docker ps --format '{{.Names}}' | grep -q "^caddy$" && \
            { docker exec -w /etc/caddy caddy caddy reload 2>/dev/null && echo "  ✓ Caddy reloaded" || echo "  ⚠ Reload manually after checking the Caddyfile"; }
    else
        echo "  ℹ Caddy not installed yet — add the (authelia) snippet + auth.${AUTHELIA_DOMAIN} block to your Caddyfile later (see README)."
    fi

    # ── README for the service folder ────────────────────────────────────────
    write_readme "$AUTHELIA_DIR" << README_MD
# Authelia — SSO + 2FA portal

Single login (with TOTP two-factor) that protects any Caddy subdomain via
forward-auth. Portal: **https://auth.${AUTHELIA_DOMAIN}**

## Layout
\`\`\`
$AUTHELIA_DIR/
├── docker-compose.yml
├── .env
├── config/
│   ├── configuration.yml
│   ├── users.yml
│   └── secrets/        # jwt/session/storage/smtp — never commit
└── data/               # sqlite db + log
\`\`\`

## Protect a service with Authelia
In that service's Caddy site block, add \`import authelia\`:
\`\`\`
myservice.${AUTHELIA_DOMAIN} {
    import authelia
    reverse_proxy localhost:PORT
}
\`\`\`
The \`(authelia)\` snippet and the \`auth.${AUTHELIA_DOMAIN}\` portal block were
added to \`$DOCKER_DIR/caddy/Caddyfile\` automatically.

## Manage
\`\`\`
cd $AUTHELIA_DIR
docker compose up -d        # start
docker compose restart authelia
docker compose logs -f authelia
docker compose down         # stop
\`\`\`

## Users
- Login with the **username** (not email). Admin user: \`${AUTHELIA_ADMIN_USER}\`.
- Tell users to click **Forgot Password** on first login to set their own
  password (Authelia emails a reset link via SMTP).
- Add a user: copy a block in \`config/users.yml\`, change username/email/
  displayname, generate a hash, then \`docker compose restart authelia\`:
\`\`\`
docker run --rm authelia/authelia:4.39.20 authelia crypto hash generate argon2 --password 'thepassword'
\`\`\`

## Notes
- Authelia listens on 9091 **internally only** (no published port) and is
  reached through Caddy on the shared \`caddy_net\` docker network.
- Two-factor is **required** (\`default_policy: deny\`, rule \`two_factor\` for
  \`*.${AUTHELIA_DOMAIN}\`).
README_MD

    local START_AUTHELIA=""
    prompt_yn "Start Authelia now? (y/n):" "y" START_AUTHELIA
    if [ "$START_AUTHELIA" = "y" ] || [ "$START_AUTHELIA" = "Y" ]; then
        docker compose up -d 2>/dev/null && log_success "Authelia started" || log_warning "Failed to start Authelia"
    fi

    echo ""
    echo "  Auth portal:  https://auth.${AUTHELIA_DOMAIN}"
    echo "  Admin login:  ${AUTHELIA_ADMIN_USER}  (use Forgot Password to set a real password)"
    echo "  README:       $AUTHELIA_DIR/README.md"
    echo ""
}