#!/usr/bin/env bash
# =============================================================================
# Airflow DAG Monitor - Offline Build Script
#
# Собирает автономный ZIP-архив со всеми зависимостями (wheel-пакеты),
# исходным кодом и скриптами установки. Архив можно перенести в закрытый
# контур без доступа в интернет и развернуть через install.sh.
#
# Использование:
#   ./build.sh
# =============================================================================
set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
VERSION=$(python3 -c "
import re, pathlib
text = pathlib.Path('$SCRIPT_DIR/airflow_monitor/__init__.py').read_text()
m = re.search(r'__version__\s*=\s*[\\x22\\x27]([^\\x22\\x27]+)', text)
print(m.group(1) if m else '0.0.0')
")
BUILD_DIR="$SCRIPT_DIR/build"
DIST_DIR="$SCRIPT_DIR/dist"
WHEELS_DIR="$BUILD_DIR/wheels"
STAGE_DIR="$BUILD_DIR/airflow-monitor-${VERSION}"

echo "=== Airflow DAG Monitor — Offline Build ==="
echo "Version:   ${VERSION}"
echo "Build dir: ${BUILD_DIR}"
echo ""

# --- Cleanup previous build ---
rm -rf "$BUILD_DIR"
mkdir -p "$WHEELS_DIR" "$STAGE_DIR" "$DIST_DIR"

# --- Step 1: Download wheel packages ---
echo "[1/4] Downloading dependencies as wheel packages..."

# Download wheels for multiple Python versions to support different servers
PYTHON_VERSIONS="39 310 311 312 313 314"
echo "  Downloading for Python versions: ${PYTHON_VERSIONS}"

for pyver in $PYTHON_VERSIONS; do
    python3 -m pip download \
        -r "$SCRIPT_DIR/requirements.txt" \
        --dest "$WHEELS_DIR" \
        --python-version "$pyver" \
        --only-binary=:all: \
        --quiet 2>/dev/null || true
done

# Also download pure-python wheels (no version constraint)
python3 -m pip download \
    -r "$SCRIPT_DIR/requirements.txt" \
    --dest "$WHEELS_DIR" \
    --quiet 2>/dev/null || true

# Deduplicate (same file may be downloaded multiple times)
WHEEL_COUNT=$(find "$WHEELS_DIR" -type f | wc -l)
echo "  Downloaded $WHEEL_COUNT packages:"
find "$WHEELS_DIR" -type f -printf "    %f\n" | sort

# --- Step 2: Stage project files ---
echo "[2/4] Staging project files..."

# Application code
cp -r "$SCRIPT_DIR/airflow_monitor" "$STAGE_DIR/airflow_monitor"
# Remove __pycache__
find "$STAGE_DIR/airflow_monitor" -type d -name __pycache__ -exec rm -rf {} + 2>/dev/null || true

# Configuration and docs
cp "$SCRIPT_DIR/config.yaml"               "$STAGE_DIR/"
cp "$SCRIPT_DIR/requirements.txt"          "$STAGE_DIR/"
cp "$SCRIPT_DIR/airflow-monitor.service"   "$STAGE_DIR/"
cp "$SCRIPT_DIR/README.md"                 "$STAGE_DIR/"

# Zabbix agent config
cp -r "$SCRIPT_DIR/zabbix" "$STAGE_DIR/zabbix"

# Wheels directory
cp -r "$WHEELS_DIR" "$STAGE_DIR/wheels"

echo "  Staged files:"
find "$STAGE_DIR" -type f -printf "    %P\n" | head -30

# --- Step 3: Generate offline install script ---
echo "[3/4] Generating install.sh..."

cat > "$STAGE_DIR/install.sh" << 'INSTALL_SCRIPT'
#!/usr/bin/env bash
# =============================================================================
# Airflow DAG Monitor - Offline Installer
#
# Устанавливает сервис из автономного архива без доступа в интернет.
# Все зависимости включены в каталог wheels/.
#
# Использование:
#   ./install.sh                          # установка в /opt/airflow-monitor
#   ./install.sh --prefix /srv/monitor    # установка в указанный каталог
# =============================================================================
set -euo pipefail

# --- Check Python version ---
PYTHON_VERSION=$(python3 -c 'import sys; print(f"{sys.version_info.major}.{sys.version_info.minor}")' 2>/dev/null || echo "0.0")
PYTHON_MAJOR=$(echo "$PYTHON_VERSION" | cut -d. -f1)
PYTHON_MINOR=$(echo "$PYTHON_VERSION" | cut -d. -f2)

if [ "$PYTHON_MAJOR" -lt 3 ] || { [ "$PYTHON_MAJOR" -eq 3 ] && [ "$PYTHON_MINOR" -lt 10 ]; }; then
    echo "ERROR: Python 3.10+ required, found Python ${PYTHON_VERSION}" >&2
    echo "" >&2
    echo "Install Python 3.10+:" >&2
    echo "  RHEL/CentOS: yum install python3.11" >&2
    echo "  ALT Linux:   apt-get install python3" >&2
    echo "  Debian:      apt install python3.11" >&2
    exit 1
fi
echo "Python version: ${PYTHON_VERSION} (OK)"

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
INSTALL_DIR="/opt/airflow-monitor"
SERVICE_USER="$(whoami)"
SERVICE_NAME="airflow-monitor"

# --- Parse arguments ---
while [[ $# -gt 0 ]]; do
    case "$1" in
        --prefix)
            INSTALL_DIR="$2"
            shift 2
            ;;
        --user)
            SERVICE_USER="$2"
            shift 2
            ;;
        -h|--help)
            echo "Usage: $0 [--prefix INSTALL_DIR] [--user SERVICE_USER]"
            echo ""
            echo "Options:"
            echo "  --prefix   Installation directory (default: /opt/airflow-monitor)"
            echo "  --user     User to run the service as (default: current user)"
            exit 0
            ;;
        *)
            echo "Unknown option: $1" >&2
            exit 1
            ;;
    esac
done

VENV_DIR="$INSTALL_DIR/venv"

echo "=== Airflow DAG Monitor — Offline Install ==="
echo "Source:      $SCRIPT_DIR"
echo "Install dir: $INSTALL_DIR"
echo "Service user: $SERVICE_USER"
echo ""

# --- Step 1: Copy files if installing to a different directory ---
if [ "$INSTALL_DIR" != "$SCRIPT_DIR" ]; then
    echo "[1/5] Copying files to $INSTALL_DIR..."
    mkdir -p "$INSTALL_DIR"
    cp -r "$SCRIPT_DIR/airflow_monitor"          "$INSTALL_DIR/"
    cp -r "$SCRIPT_DIR/wheels"                    "$INSTALL_DIR/"
    cp -r "$SCRIPT_DIR/zabbix"                    "$INSTALL_DIR/"
    cp    "$SCRIPT_DIR/config.yaml"               "$INSTALL_DIR/"
    cp    "$SCRIPT_DIR/requirements.txt"          "$INSTALL_DIR/"
    cp    "$SCRIPT_DIR/airflow-monitor.service"   "$INSTALL_DIR/"
    cp    "$SCRIPT_DIR/README.md"                 "$INSTALL_DIR/"
    echo "  Done"
else
    echo "[1/5] Installing in place, skipping copy"
fi

# --- Step 2: Create virtual environment ---
echo "[2/5] Creating Python virtual environment..."
if [ -d "$VENV_DIR" ]; then
    rm -rf "$VENV_DIR"
fi
python3 -m venv "$VENV_DIR"
echo "  Created: $VENV_DIR"

# --- Step 3: Install dependencies from local wheels ---
echo "[3/5] Installing dependencies from local wheels (offline)..."
"$VENV_DIR/bin/pip" install \
    --no-index \
    --find-links "$INSTALL_DIR/wheels" \
    -r "$INSTALL_DIR/requirements.txt" \
    --quiet
echo "  Installed packages:"
"$VENV_DIR/bin/pip" list --format=columns 2>/dev/null | grep -vE '^(Package|---)'
echo ""

# --- Step 4: Create required directories ---
echo "[4/5] Creating directories..."

STATE_DIR="/var/lib/airflow-monitor"
LOG_DIR="/var/log/airflow-monitor"

for dir in "$STATE_DIR" "$LOG_DIR"; do
    if [ ! -d "$dir" ]; then
        sudo mkdir -p "$dir"
        sudo chown "${SERVICE_USER}:$(id -gn "$SERVICE_USER")" "$dir"
        echo "  Created: $dir"
    else
        echo "  Exists:  $dir"
    fi
done

# --- Step 5: Install systemd service ---
echo "[5/5] Installing systemd service..."

# Patch service file with actual paths and user
SERVICE_FILE="$INSTALL_DIR/airflow-monitor.service"
if [ -f "$SERVICE_FILE" ]; then
    TEMP_SERVICE=$(mktemp)
    sed \
        -e "s|User=.*|User=${SERVICE_USER}|" \
        -e "s|Group=.*|Group=$(id -gn "$SERVICE_USER")|" \
        -e "s|WorkingDirectory=.*|WorkingDirectory=${INSTALL_DIR}|" \
        -e "s|ExecStart=.*|ExecStart=${VENV_DIR}/bin/python -m airflow_monitor --config ${INSTALL_DIR}/config.yaml|" \
        "$SERVICE_FILE" > "$TEMP_SERVICE"

    sudo cp "$TEMP_SERVICE" /etc/systemd/system/${SERVICE_NAME}.service
    rm -f "$TEMP_SERVICE"
    sudo systemctl daemon-reload
    echo "  Installed: /etc/systemd/system/${SERVICE_NAME}.service"
else
    echo "  WARNING: service file not found, skipping"
fi

# --- Step 6: Install Zabbix agent config ---
echo "[6/6] Installing Zabbix agent config..."
ZABBIX_CONF_SRC="$INSTALL_DIR/zabbix/airflow-monitor.conf"
ZABBIX_CONF_DST="/etc/zabbix/zabbix_agentd.conf.d/airflow-monitor.conf"

if [ -f "$ZABBIX_CONF_SRC" ]; then
    if [ -d "/etc/zabbix/zabbix_agentd.conf.d" ]; then
        sudo cp "$ZABBIX_CONF_SRC" "$ZABBIX_CONF_DST"
        sudo chmod 644 "$ZABBIX_CONF_DST"
        echo "  Installed: $ZABBIX_CONF_DST"
        if systemctl is-active zabbix-agent >/dev/null 2>&1; then
            sudo systemctl restart zabbix-agent
            echo "  Restarted: zabbix-agent"
        elif systemctl is-active zabbix-agent2 >/dev/null 2>&1; then
            sudo systemctl restart zabbix-agent2
            echo "  Restarted: zabbix-agent2"
        else
            echo "  WARNING: zabbix-agent not running, restart manually"
        fi
    else
        echo "  WARNING: /etc/zabbix/zabbix_agentd.conf.d/ not found"
        echo "  Copy manually: sudo cp $ZABBIX_CONF_SRC $ZABBIX_CONF_DST"
    fi
else
    echo "  WARNING: zabbix config not found"
fi

# Ensure data dir is readable by zabbix agent
sudo chmod 755 /var/lib/airflow-monitor 2>/dev/null || true

echo ""
echo "=== Install Complete ==="
echo ""
echo "Next steps:"
echo "  1. Edit config.yaml:"
echo "     vim $INSTALL_DIR/config.yaml"
echo ""
echo "  2. Test manually:"
echo "     $VENV_DIR/bin/python -m airflow_monitor --discover -c $INSTALL_DIR/config.yaml"
echo ""
echo "  3. Enable and start:"
echo "     sudo systemctl enable --now $SERVICE_NAME"
echo ""
echo "  4. Check logs:"
echo "     journalctl -u $SERVICE_NAME -f"
echo ""
echo "  5. Verify Zabbix agent reads data:"
echo "     zabbix_agentd -t airflow.monitor.heartbeat"
echo "     zabbix_agentd -t airflow.dag.problems.count"
INSTALL_SCRIPT

chmod +x "$STAGE_DIR/install.sh"
echo "  Generated: install.sh"

# --- Step 4: Create archive ---
echo "[4/4] Creating tar.gz archive..."

ARCHIVE_NAME="airflow-monitor-${VERSION}.tar.gz"
ARCHIVE_PATH="$DIST_DIR/$ARCHIVE_NAME"

(cd "$BUILD_DIR" && tar czf "$ARCHIVE_PATH" "airflow-monitor-${VERSION}")

ARCHIVE_SIZE=$(du -h "$ARCHIVE_PATH" | cut -f1)

echo "  Archive: $ARCHIVE_PATH"
echo "  Size:    $ARCHIVE_SIZE"

# --- Cleanup build directory ---
rm -rf "$BUILD_DIR"

echo ""
echo "=== Build Complete ==="
echo ""
echo "Архив для переноса в закрытый контур:"
echo "  $ARCHIVE_PATH"
echo ""
echo "Развёртывание на целевом сервере:"
echo "  1. Скопировать: scp $ARCHIVE_PATH user@target:/tmp/"
echo "  2. Распаковать: tar xzf /tmp/$ARCHIVE_NAME -C /tmp/"
echo "  3. Установить:  cd /tmp/airflow-monitor-${VERSION} && ./install.sh"
echo ""
echo "По умолчанию устанавливается в /opt/airflow-monitor."
echo "Для смены каталога или пользователя:"
echo "  ./install.sh --prefix /srv/airflow-monitor --user airflow"