package common

import (
	"path"
	"regexp"
	"strings"
)

// ParseSubprojectChangesFromDiff parses a diff string and returns a slice of package names that have changed.
// It identifies subproject changes by looking for "Subproject commit" lines within diff chunks.
func ParseSubprojectChangesFromDiff(diff string) []string {
	var changedPackages []string

	// This regex finds diff chunks for subprojects.
	// It looks for a `diff --git` line, followed by lines indicating a subproject commit change.
	re := regexp.MustCompile(`diff --git a\/(.+) b\/(.+)\n`)

	matches := re.FindAllStringSubmatch(diff, -1)

	for _, match := range matches {
		if len(match) > 1 {
			// The package path is in the first capturing group.
			// We use path.Base to get just the package name from the path (e.g., "rpms/iptraf-ng" -> "iptraf-ng").
			pkgPath := strings.TrimSpace(match[1])
			basePath := path.Base(pkgPath)
			// TODO: parse _manifest files to get real package names
			if basePath != ".gitmodules" && basePath != "_config" && basePath != "" {
				changedPackages = append(changedPackages, basePath)
			}
		}
	}

	return changedPackages
}