package scanner

import (
	"path/filepath"
	"strings"
)

// detectLanguage returns a best-effort language label based on the
// file extension. Empty string for unknown — the caller treats those
// as opaque and may still scan them for patterns.
func detectLanguage(filename string) string {
	switch strings.ToLower(filepath.Ext(filename)) {
	case ".go":
		return "Go"
	case ".rs":
		return "Rust"
	case ".ts", ".tsx":
		return "TypeScript"
	case ".js", ".jsx", ".mjs", ".cjs":
		return "JavaScript"
	case ".py":
		return "Python"
	case ".java":
		return "Java"
	case ".kt":
		return "Kotlin"
	case ".rb":
		return "Ruby"
	case ".php":
		return "PHP"
	case ".swift":
		return "Swift"
	case ".c", ".h":
		return "C"
	case ".cpp", ".cc", ".cxx", ".hpp":
		return "C++"
	case ".cs":
		return "C#"
	case ".sh", ".bash":
		return "Shell"
	case ".sql":
		return "SQL"
	case ".yaml", ".yml":
		return "YAML"
	case ".toml":
		return "TOML"
	case ".json":
		return "JSON"
	case ".md", ".markdown":
		return "Markdown"
	case ".html", ".htm":
		return "HTML"
	case ".css", ".scss", ".sass", ".less":
		return "CSS"
	}
	// Special filenames without extensions
	switch strings.ToLower(filename) {
	case "dockerfile", "containerfile":
		return "Docker"
	case "makefile", "gnumakefile":
		return "Make"
	case "justfile":
		return "Justfile"
	}
	return ""
}