#!/bin/bash
set -e

POSTGRES_VERSION="${POSTGRES_VERSION:-16}"
POSTGRES_DATA_DIR="${POSTGRES_DATA_DIR:-/data/postgres}"
POSTGRES_USER="${POSTGRES_USER:-vibestack}"
POSTGRES_PASSWORD="${POSTGRES_PASSWORD:-vibestack}"
POSTGRES_DB="${POSTGRES_DB:-vibestack}"
POSTGRES_INITDB_ARGS="${POSTGRES_INITDB_ARGS:-}"

# Idempotent PostgreSQL installation
install_postgres() {
    if command -v psql &>/dev/null; then
        echo "PostgreSQL already installed: $(psql --version)"
        return 0
    fi

    echo "Installing PostgreSQL ${POSTGRES_VERSION}..."

    # Install dependencies and add PostgreSQL repo
    apt-get update
    apt-get install -y curl ca-certificates gnupg lsb-release

    # Add PostgreSQL APT repository
    curl -fsSL https://www.postgresql.org/media/keys/ACCC4CF8.asc | gpg --dearmor -o /usr/share/keyrings/postgresql-keyring.gpg
    echo "deb [signed-by=/usr/share/keyrings/postgresql-keyring.gpg] http://apt.postgresql.org/pub/repos/apt $(lsb_release -cs)-pgdg main" > /etc/apt/sources.list.d/pgdg.list

    # Install PostgreSQL
    apt-get update
    apt-get install -y "postgresql-${POSTGRES_VERSION}"

    echo "PostgreSQL installed: $(psql --version)"
}

# Setup directories and permissions
setup_dirs() {
    mkdir -p "$POSTGRES_DATA_DIR"
    chown -R postgres:postgres "$POSTGRES_DATA_DIR"
    chmod 700 "$POSTGRES_DATA_DIR"

    echo "PostgreSQL data directory: $POSTGRES_DATA_DIR"
}

# Initialize database if not exists
init_database() {
    if [ -f "$POSTGRES_DATA_DIR/PG_VERSION" ]; then
        echo "Database already initialized"
        return 0
    fi

    echo "Initializing database..."

    # Initialize with specified args
    su - postgres -c "/usr/lib/postgresql/${POSTGRES_VERSION}/bin/initdb -D '$POSTGRES_DATA_DIR' $POSTGRES_INITDB_ARGS"

    # Configure PostgreSQL
    cat >> "$POSTGRES_DATA_DIR/postgresql.conf" << EOF

# VibeStack configuration
listen_addresses = '*'
port = ${POSTGRES_PORT:-5432}
max_connections = ${POSTGRES_MAX_CONNECTIONS:-100}
EOF

    # Configure authentication
    cat > "$POSTGRES_DATA_DIR/pg_hba.conf" << EOF
# TYPE  DATABASE        USER            ADDRESS                 METHOD
local   all             postgres                                peer
local   all             all                                     md5
host    all             all             127.0.0.1/32            md5
host    all             all             ::1/128                 md5
host    all             all             0.0.0.0/0               md5
EOF

    echo "Database initialized"
}

# Create default user and database
create_user_and_db() {
    local pg_ctl="/usr/lib/postgresql/${POSTGRES_VERSION}/bin/pg_ctl"
    local psql_cmd="/usr/lib/postgresql/${POSTGRES_VERSION}/bin/psql"

    # Start PostgreSQL temporarily
    echo "Starting PostgreSQL for initial setup..."
    su - postgres -c "$pg_ctl -D '$POSTGRES_DATA_DIR' -w start"

    # Create user if not exists
    if ! su - postgres -c "$psql_cmd -tAc \"SELECT 1 FROM pg_roles WHERE rolname='$POSTGRES_USER'\"" | grep -q 1; then
        echo "Creating user: $POSTGRES_USER"
        su - postgres -c "$psql_cmd -c \"CREATE USER $POSTGRES_USER WITH PASSWORD '$POSTGRES_PASSWORD'\""
    fi

    # Create database if not exists
    if ! su - postgres -c "$psql_cmd -tAc \"SELECT 1 FROM pg_database WHERE datname='$POSTGRES_DB'\"" | grep -q 1; then
        echo "Creating database: $POSTGRES_DB"
        su - postgres -c "$psql_cmd -c \"CREATE DATABASE $POSTGRES_DB OWNER $POSTGRES_USER\""
    fi

    # Grant privileges
    su - postgres -c "$psql_cmd -c \"GRANT ALL PRIVILEGES ON DATABASE $POSTGRES_DB TO $POSTGRES_USER\""

    # Run init scripts if present
    local skill_dir="$(dirname "$(dirname "$0")")"
    local initdb_dir="$skill_dir/initdb.d"

    if [ -d "$initdb_dir" ]; then
        echo "Running init scripts..."
        for f in "$initdb_dir"/*.sql; do
            if [ -f "$f" ]; then
                echo "  Running: $(basename "$f")"
                su - postgres -c "PGPASSWORD='$POSTGRES_PASSWORD' $psql_cmd -U $POSTGRES_USER -d $POSTGRES_DB -f '$f'"
            fi
        done
    fi

    # Stop PostgreSQL (run.sh will start it properly)
    echo "Stopping PostgreSQL after setup..."
    su - postgres -c "$pg_ctl -D '$POSTGRES_DATA_DIR' -w stop"

    echo "User and database setup complete"
}

install_postgres
setup_dirs
init_database
create_user_and_db

echo "PostgreSQL setup complete"