//go:build linux || freebsd
// +build linux freebsd

package cli

import (
	_ "embed"
	"fmt"
	"io"
	"os"
	"strings"
)

//go:embed help.txt
var helpText string

// ANSI color codes
const (
	ColorReset   = "\033[0m"
	ColorGreen   = "\033[32m"
	ColorCyan    = "\033[36m"
	ColorYellow  = "\033[33m"
	ColorBlue    = "\033[34m"
	ColorRed     = "\033[31m"
	ColorBold    = "\033[1m"
	ColorMagenta = "\033[35m"
)

// isColorTerminal checks if writer supports ANSI colors
func isColorTerminal(w io.Writer) bool {
	if os.Getenv("NO_COLOR") != "" {
		return false
	}
	if _, ok := w.(*os.File); ok {
		return os.Getenv("TERM") != "dumb"
	}
	return false
}

// PrintUsage prints formatted help from embedded help.txt
func PrintUsage(w io.Writer) {
	useColors := isColorTerminal(w)

	if useColors {
		bold := ColorBold
		reset := ColorReset
		green := ColorGreen
		yellow := ColorYellow
		magenta := ColorMagenta
		_ = bold
		_ = reset
		_ = green
		_ = yellow
		_ = magenta

		// Print help text with ANSI colors for section headers
		for _, line := range strings.Split(helpText, "\n") {
			if strings.HasPrefix(line, "NAME") || strings.HasPrefix(line, "SYNOPSIS") ||
				strings.HasPrefix(line, "DESCRIPTION") || strings.HasSuffix(strings.TrimRight(line, " "), ":") {
				fmt.Fprintf(w, "%s%s%s\n", ColorBold, line, ColorReset)
			} else {
				fmt.Fprintln(w, line)
			}
		}
	} else {
		fmt.Fprint(w, helpText)
	}
}

// PrintCategoryHelp prints help filtered by category.
// Categories: all, target, network, auth, mirror, recursive, verify, queue, metalink, upload, pgp, extraction, config
func PrintCategoryHelp(w io.Writer, category string) {
	if category == "" || category == "all" {
		PrintUsage(w)
		return
	}

	categories := map[string]string{
		"target":     "TARGETS",
		"network":    "NETWORK",
		"auth":       "AUTHENTICATION",
		"mirror":     "MIRROR MODE",
		"recursive":  "RECURSIVE DOWNLOAD",
		"verify":     "VERIFICATION",
		"queue":      "DOWNLOAD QUEUE",
		"metalink":   "METALINK",
		"upload":     "BASIC OPTIONS",
		"pgp":        "PGP/GPG",
		"extraction": "EXTRACTION",
		"config":     "CONFIGURATION",
	}

	title, ok := categories[strings.ToLower(category)]
	if !ok {
		fmt.Fprintf(w, "Unknown category: %s\nAvailable: %s\n", category,
			"target, network, auth, mirror, recursive, verify, queue, metalink, upload, pgp, extraction, config, all")
		return
	}
	fmt.Fprintf(w, "Showing category: %s\nUse --help for full help.\n\n", title)
	PrintUsage(w) // For now, print full help — future: filter
}