package main

import (
	"fmt"
	"strings"
)

// serviceVersion runs git describe in the service directory and returns
// the version string. If strict is true, it rejects versions that are
// dirty or not exactly on a tag.
func serviceVersion(svcPath string, strict bool) (string, error) {
	version, err := runOutput(svcPath, "git", "describe", "--tags", "--always", "--dirty")
	if err != nil {
		return "", fmt.Errorf("git describe in %s: %w", svcPath, err)
	}

	if strict {
		if strings.HasSuffix(version, "-dirty") {
			return "", fmt.Errorf("--strict: working tree is dirty (%s); commit or stash changes before building", version)
		}
		// git describe produces "v1.0.0-3-gabcdef" when HEAD is 3 commits past a tag.
		// A clean tag has no hyphen after the version (except pre-release like v1.0.0-rc1,
		// which we allow). Detect the "-N-gHASH" suffix.
		if parts := strings.Split(version, "-"); len(parts) >= 3 {
			// Check if second-to-last part is a number (commit count).
			secondToLast := parts[len(parts)-2]
			if len(secondToLast) > 0 && secondToLast[0] >= '0' && secondToLast[0] <= '9' {
				last := parts[len(parts)-1]
				if strings.HasPrefix(last, "g") {
					return "", fmt.Errorf("--strict: HEAD is not on a tag (%s); create a tag before building", version)
				}
			}
		}
	}

	return version, nil
}