// Copyright (c) 2026, Pim van Pelt <pim@ipng.ch>

package main

import "strings"

const (
	ansiBlue  = "\x1b[34m"
	ansiRed   = "\x1b[31m"
	ansiReset = "\x1b[0m"
)

// colorEnabled is set by the -color flag in main.
var colorEnabled bool

// label wraps s in dark-blue ANSI when color output is enabled.
//
// Tabwriter caveat: tabwriter.Writer counts *bytes* per cell, not
// rendered columns. ANSI escape codes (`\x1b[34m…\x1b[0m`, 11 bytes)
// inflate a cell's apparent width without affecting what the terminal
// draws. Two things follow:
//
//  1. Key-value layouts where column 1 is *always* labelled and
//     column 2 is *always* plain (e.g. `show vpp info`) stay aligned,
//     because every row adds the same 11 bytes to column 1.
//  2. Multi-column tables where only the *header* row is labelled
//     drift: the header cells each carry 11 extra bytes that the data
//     rows don't, so data cells get over-padded. In those tables,
//     leave the header plain (see runShowVPPLBCounters) and only use
//     label() for labels that appear uniformly column-wise.
func label(s string) string {
	if !colorEnabled {
		return s
	}
	return ansiBlue + s + ansiReset
}

// formatError returns a user-friendly error string. gRPC status errors are
// unwrapped to show only the server's message (no "rpc error: code = ..."
// boilerplate). The result is wrapped in red ANSI when color is enabled.
func formatError(err error) string {
	msg := err.Error()
	// google.golang.org/grpc/status errors format as:
	//   rpc error: code = <Code> desc = <message>
	if i := strings.Index(msg, " desc = "); i >= 0 {
		msg = msg[i+len(" desc = "):]
	}
	if colorEnabled {
		return ansiRed + msg + ansiReset
	}
	return msg
}