#!/bin/bash
# services/calibre-web.sh — Ebook library web UI with metadata editing (Calibre-Web).
# Part of the modular post-install system (sourced by setup.sh).
#
# Can also be run standalone on any machine:
#   sudo bash calibre-web.sh
# (Docker must already be installed when run standalone)

# ── Standalone bootstrap ──────────────────────────────────────────────────────
if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
    [[ "$(id -u)" == "0" ]] || { echo "Run with sudo: sudo bash $0"; exit 1; }

    _SELF_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
    _COMMON="$_SELF_DIR/../lib/common.sh"

    if [[ -f "$_COMMON" ]]; then
        source "$_COMMON"
    else
        log_info()    { echo -e "\033[0;34m[INFO]\033[0m $*"; }
        log_success() { echo -e "\033[0;32m[OK]\033[0m $*"; }
        log_warning() { echo -e "\033[1;33m[WARN]\033[0m $*"; }
        log_error()   { echo -e "\033[0;31m[ERROR]\033[0m $*" >&2; }

        require_docker() {
            command -v docker &>/dev/null || {
                log_error "Docker not found. Install it first:"
                log_error "  curl -fsSL https://get.docker.com | sudo sh"
                return 1
            }
            docker compose version &>/dev/null || {
                log_error "Docker Compose plugin missing:"
                log_error "  sudo apt-get install -y docker-compose-plugin"
                return 1
            }
        }

        ensure_docker_dir_ownership() {
            chown -R "$ACTUAL_USER:$ACTUAL_USER" "$@" 2>/dev/null || true
        }

        port_in_use() {
            local _port="$1" _proto="${2:-tcp}"
            local _flag="-tlnH"
            [ "$_proto" = "udp" ] && _flag="-ulnH"
            ss "$_flag" "sport = :${_port}" 2>/dev/null | grep -q .
        }

        find_free_port() {
            local _varname="$1" _port="$2" _proto="${3:-tcp}"
            while port_in_use "$_port" "$_proto"; do
                _port=$((_port + 1))
            done
            eval "$_varname='$_port'"
        }

        prompt_text() {
            local _q="$1" _def="$2" _var="$3" _r
            [[ "${UNATTENDED:-false}" == "true" ]] && { eval "$_var='$_def'"; return; }
            read -r -p "  $_q " _r
            eval "$_var='${_r:-$_def}'"
        }

        prompt_yn() {
            local _q="$1" _def="$2" _var="$3" _r
            [[ "${UNATTENDED:-false}" == "true" ]] && { eval "$_var='$_def'"; return; }
            read -r -p "  $_q " _r
            eval "$_var='${_r:-$_def}'"
        }

        configure_caddy_for_service() {
            local _name="$1" _upstream="$2" _subdomain="$3" _extra="${4:-}"
            local _caddy_dir="$DOCKER_DIR/caddy"
            local _caddyfile="$_caddy_dir/Caddyfile"
            local _display_port="${_upstream##*:}"

            # Determine mode: local Caddy, remote Caddy, or none
            local _mode="none"
            [[ -d "$_caddy_dir" ]] && _mode="local"
            [[ -n "${CADDY_REMOTE_HOST:-}" ]] && [[ "$_mode" != "local" ]] && _mode="remote"
            [[ "$_mode" == "none" ]] && {
                log_info "Access $_name directly on port $_display_port."
                return 0
            }

            echo ""
            local _do_caddy=""
            if [[ "$_mode" == "remote" ]]; then
                log_info "Remote Caddy configured (${CADDY_REMOTE_HOST})."
                log_info "A snippet file will be saved to ~/docker/caddy-snippets/."
            fi
            read -r -p "  Configure Caddy reverse proxy for $_name? [y/N]: " _do_caddy
            [[ "${_do_caddy,,}" == "y" ]] || {
                log_info "Skipping — access at: http://localhost:$_display_port"
                return 0
            }

            # Domain prompt — pre-fill from SITE_DOMAIN when available
            local _default_domain=""
            if [[ -n "${SITE_DOMAIN:-}" ]] && [[ "$SITE_DOMAIN" != "example.com" ]]; then
                _default_domain="${_subdomain}.${SITE_DOMAIN}"
                log_info "Default: $_default_domain"
            fi
            local _domain=""
            read -r -p "  Domain [${_default_domain:-required}]: " _domain
            _domain="${_domain:-$_default_domain}"
            [[ -n "$_domain" ]] || { log_warning "No domain entered — skipping Caddy."; return 0; }

            # Build upstream — remote Caddy uses host IP:port, not container name
            local _block_upstream="$_upstream"
            if [[ "$_mode" == "remote" ]]; then
                _block_upstream="${CADDY_REMOTE_HOST}:${_display_port}"
            fi

            local _site_block
            _site_block="$(cat << CBLOCK

# $_name
${_domain} {
    reverse_proxy ${_block_upstream}

    header {
        Strict-Transport-Security "max-age=31536000; includeSubDomains; preload"
        X-Content-Type-Options "nosniff"
        X-Frame-Options "SAMEORIGIN"
        Referrer-Policy "strict-origin-when-cross-origin"
    }

    log {
        output file /var/log/caddy/${_domain}.log
        format json
    }
${_extra}
}
CBLOCK
)"

            if [[ "$_mode" == "local" ]]; then
                if [[ -f "$_caddyfile" ]]; then
                    local _bk="$_caddy_dir/Caddyfile.backup.$(date +%Y%m%d-%H%M%S)"
                    cp "$_caddyfile" "$_bk"
                    log_info "Backed up Caddyfile to $(basename "$_bk")"
                else
                    touch "$_caddyfile"
                fi

                if grep -q "^${_domain}" "$_caddyfile" 2>/dev/null; then
                    log_warning "$_domain already in Caddyfile"
                    local _ow=""
                    read -r -p "  Overwrite? [y/N]: " _ow
                    [[ "${_ow,,}" == "y" ]] || { log_info "Keeping existing entry."; return 0; }
                    sed -i "/^${_domain}/,/^}/d" "$_caddyfile"
                fi

                printf '%s\n' "$_site_block" >> "$_caddyfile"
                log_success "Added $_domain to Caddyfile"
                docker exec caddy caddy fmt --overwrite /etc/caddy/Caddyfile 2>/dev/null || true
                if docker exec caddy caddy reload --config /etc/caddy/Caddyfile 2>/dev/null; then
                    log_success "$_name accessible at: https://$_domain"
                else
                    log_warning "Reload failed — check: docker logs caddy"
                    log_info "Manual reload: docker exec caddy caddy reload --config /etc/caddy/Caddyfile"
                fi
            else
                local _snippet_dir="$DOCKER_DIR/caddy-snippets"
                local _snippet_file="$_snippet_dir/${_subdomain}.caddy"
                mkdir -p "$_snippet_dir"
                printf '%s\n' "$_site_block" > "$_snippet_file"
                chown "$ACTUAL_USER:$ACTUAL_USER" "$_snippet_file" 2>/dev/null || true
                log_success "Snippet saved: $_snippet_file"
                log_info "Copy to Caddy machine:"
                log_info "  scp $_snippet_file caddy-host:~/caddy-snippets/"
                log_info "  rsync -av $_snippet_dir/ caddy-host:~/caddy-snippets/  (all at once)"
            fi
        }
        write_readme() {
            local _dir="$1"; shift
            mkdir -p "$_dir"
            cat > "$_dir/README.md"
        }
    fi

    ACTUAL_USER="${ACTUAL_USER:-${SUDO_USER:-$USER}}"
    ACTUAL_HOME="$(getent passwd "$ACTUAL_USER" 2>/dev/null | cut -d: -f6 || echo "${HOME:-/root}")"
    DOCKER_DIR="${DOCKER_DIR:-$ACTUAL_HOME/docker}"
    DRY_RUN="${DRY_RUN:-false}"
    UNATTENDED="${UNATTENDED:-false}"
    SITE_TZ="${SITE_TZ:-$(cat /etc/timezone 2>/dev/null || echo UTC)}"
    SITE_DOMAIN="${SITE_DOMAIN:-example.com}"
    SITE_CADDY_NET="${SITE_CADDY_NET:-caddy_net}"
    CADDY_REMOTE_HOST="${CADDY_REMOTE_HOST:-}"

    register_service() { :; }
    _RUN_STANDALONE=1
fi
# ─────────────────────────────────────────────────────────────────────────────

register_service calibre-web media "Ebook library web UI with metadata editing (Calibre-Web)" 8083

install_calibre-web() {
    require_docker || return 1
    log_info "Installing Calibre-Web..."

    local CW_DIR="$DOCKER_DIR/calibre-web"
    local WEB_PORT="8083"

    if [ "$DRY_RUN" = true ]; then
        echo "[DRY-RUN] Would create $CW_DIR"
        echo "[DRY-RUN] Would write docker-compose.yml and .env"
        echo "[DRY-RUN] Would auto-scan for a free host port"
        return 0
    fi

    # Scan for a free host port — a plain install shouldn't silently claim a
    # port another already-running service holds. See CLAUDE.md's "Port
    # collision avoidance" section.
    find_free_port WEB_PORT "$WEB_PORT"

    mkdir -p "$CW_DIR/config" "$CW_DIR/books"
    ensure_docker_dir_ownership "$CW_DIR"
    cd "$CW_DIR" || return 1

    # Mirrors configure_caddy_for_service's own mode resolution (lib/common.sh):
    # explicit CADDY_MODE from the site config wins, then a local ~/docker/caddy,
    # then the legacy CADDY_REMOTE_HOST var. Only "local" joins caddy_net — a
    # remote Caddy box can't resolve container names on this host's bridge
    # network anyway; it reaches this service via the host's published port.
    local _CADDY_MODE="${CADDY_MODE:-none}"
    [ "$_CADDY_MODE" = "none" ] && [ -d "$DOCKER_DIR/caddy" ] && _CADDY_MODE="local"
    [ "$_CADDY_MODE" = "none" ] && [ -n "${CADDY_REMOTE_HOST:-}" ] && _CADDY_MODE="remote"

    local _CADDY_NET_BLOCK=""
    local _CADDY_NET_SECTION=""
    if [ "$_CADDY_MODE" = "local" ]; then
        _CADDY_NET_BLOCK="    networks:
      - caddy_net
"
        _CADDY_NET_SECTION="
networks:
  caddy_net:
    external: true
    name: ${SITE_CADDY_NET:-caddy_net}
"
    fi

    cat > docker-compose.yml << CW_COMPOSE
name: calibre-web

services:
  calibre-web:
    image: lscr.io/linuxserver/calibre-web:latest
    container_name: calibre-web
    hostname: calibre-web
    restart: unless-stopped
    environment:
      - PUID=1000
      - PGID=1000
      - TZ=${SITE_TZ:-UTC}
      - DOCKER_MODS=linuxserver/mods:universal-calibre
    volumes:
      - ./config:/config
      - ./books:/books
    ports:
      - "${WEB_PORT}:8083"
${_CADDY_NET_BLOCK}${_CADDY_NET_SECTION}
CW_COMPOSE

    cat > .env << CW_ENV
CADDY_NET=$SITE_CADDY_NET
CW_ENV

    chown -R "$ACTUAL_USER:$ACTUAL_USER" "$CW_DIR"

    echo ""
    log_success "Calibre-Web configured at $CW_DIR"

    configure_caddy_for_service "Calibre-Web" "calibre-web:8083" "books"

    write_readme "$CW_DIR" << MD
# Calibre-Web

Web-based ebook library with metadata editing, reading, and format conversion
powered by Calibre.

## First-run setup
1. Open the UI (http://localhost:${WEB_PORT}) and log in with admin / admin123
2. When prompted for the database location, enter: \`/books\`
   (point this at your existing Calibre library or an empty directory)
3. Change the default password immediately under Admin → Edit User

## Ebook conversion
The \`DOCKER_MODS=linuxserver/mods:universal-calibre\` environment variable
installs the full Calibre binary inside the container, enabling on-the-fly
ebook conversion (e.g. EPUB → MOBI/AZW3).

## Books directory
Place your Calibre library (or individual books) in:
  ~/docker/calibre-web/books/

If you already have a Calibre library elsewhere, mount that path instead by
editing the \`./books:/books\` volume line in docker-compose.yml.

## Manage
\`\`\`bash
docker compose up -d
docker compose down
docker compose logs -f
docker compose pull && docker compose down && docker compose up -d
\`\`\`
MD

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

    echo "  Access at:  http://localhost:8083"
    echo "  Default login: admin / admin123 (change immediately!)"
    echo "  Point the database to /books on first run."
    echo ""
}

# Run immediately when executed directly (deferred until after function definition)
[[ "${_RUN_STANDALONE:-0}" == 1 ]] && install_calibre-web
