#!/bin/sh
# Build a Docker image locally.
#
# Usage (interactive — prompts for missing values):
#   ./ops/build-image.sh
#
# Usage (non-interactive — all values as positional args):
#   ./ops/build-image.sh <tag> <image>
#
# Example:
#   ./ops/build-image.sh v1.0 registry.example.com/myorg/myapp

set -eu

ROOT_DIR=$(CDPATH= cd -- "$(dirname "$0")/.." && pwd)

command -v docker >/dev/null 2>&1 || { echo "error: docker not found in PATH" >&2; exit 1; }

DEFAULT_TAG=$(git -C "${ROOT_DIR}" rev-parse --short HEAD 2>/dev/null || echo dev)

ask() {
    if [ -n "$3" ]; then
        printf "%s [%s]: " "$2" "$3" >&2
    else
        printf "%s: " "$2" >&2
    fi
    read -r _val
    eval "$1=\"\${_val:-$3}\""
}

if [ $# -ge 2 ]; then
    IMAGE_TAG="$1"
    IMAGE="$2"
elif [ $# -ge 1 ]; then
    IMAGE_TAG="$1"
    ask IMAGE "Image" ""
else
    ask IMAGE_TAG "Tag"   "${DEFAULT_TAG}"
    ask IMAGE     "Image" ""
fi

echo "building ${IMAGE}:${IMAGE_TAG}"
docker build \
    -f "${ROOT_DIR}/Dockerfile" \
    -t "${IMAGE}:${IMAGE_TAG}" \
    -t "${IMAGE}:latest" \
    "${ROOT_DIR}"