package cobol

import (
	"os"
	"strings"
	"unicode"

	"go.wit.com/log"
	"golang.org/x/term"
)

var WIDTH int = 120

// getTerminalWidth returns the width of the active terminal.
// If the output is not an interactive terminal (e.g., it's being piped to a file
// or another command), it returns a default width and false.
func getTerminalWidth() (int, bool) {
	// term.IsTerminal checks if the given file descriptor is connected to a terminal.
	// We use os.Stdout.Fd() to check the standard output.
	if term.IsTerminal(int(os.Stdout.Fd())) {
		var err error
		// term.GetSize returns the dimensions of the given terminal.
		WIDTH, _, err = term.GetSize(int(os.Stdout.Fd()))
		if err != nil {
			// If we can't get the size for some reason, fall back to the default.
			log.Printf("could not get terminal size: %v", err)
			return WIDTH, false
		}
		return WIDTH, true
	}

	// If it's not a terminal, return the default width.
	return WIDTH, false
}

// like the perl Chomp but with the terminal width
func TerminalChomp(cut string) string {
	i, _ := getTerminalWidth()
	// log.Info("cobol.TerminalCut() at ", i)

	// TrimRightFunc removes all trailing runes r from the string s that satisfy f(r).
	// unicode.IsSpace reports whether the rune is a space character.
	cut = strings.TrimRightFunc(cut, unicode.IsSpace)

	if i >= len(cut) {
		return cut
	} else {
		return log.Sprintf("%s", cut[0:i])
	}
}