Function WriteGlobalConfig

internal/sshconfig/global.go:32–88

WriteGlobalConfig writes or updates the Host * configuration Creates the block at the END of config file if it doesn't exist

(cfg *HostConfig)

// WriteGlobalConfig writes or updates the Host * configuration
// Creates the block at the END of config file if it doesn't exist
func WriteGlobalConfig(cfg *HostConfig) error {
	// Mark as global
	cfg.Name = "*"
	cfg.IsGlobal = true

	// Validate configuration (allows missing Hostname)
	if err := ValidateHostConfig(cfg); err != nil {
		return fmt.Errorf("invalid global config: %w", err)
	}

	// Create backup
	backupPath, err := backupSSHConfig()
	if err != nil {
		return fmt.Errorf("backup failed: %w", err)
	}

	// Read current config
	lines, err := readSSHConfigLines()
	if err != nil {
		return err
	}

	// Find existing Host * block
	start, end, found := findHostBlock(lines, "*")

	// Render new Host * block
	newBlock := renderHostBlock(cfg)
	newBlockLines := strings.Split(strings.TrimRight(newBlock, "\n"), "\n")

	// Construct updated config
	var result []string
	if found {
		// Replace existing block IN PLACE
		result = append(result, lines[:start]...)
		result = append(result, newBlockLines...)
		result = append(result, lines[end:]...)
	} else {
		// Append to end of file (SSH best practice: Host * at the end)
		result = append(result, lines...)
		if len(result) > 0 && result[len(result)-1] != "" {
			result = append(result, "") // Blank line before Host *
		}
		result = append(result, newBlockLines...)
	}

	// Write updated config
	if err := writeSSHConfigLines(result); err != nil {
		// Restore backup on failure
		if backupPath != "" {
			configPath := sshConfigPath()
			_ = copyFile(backupPath, configPath)
		}
		return err
	}

	return nil
}