FieldData.swift

//
//  FieldData.swift
//
//
//  Created by chen on 2023/11/11.
//

import Foundation

extension FieldData {
#if canImport(CoreFoundation.CFString) && canImport(CoreFoundation.CFStringEncodingExt)
    public static var big5Encoding: String.Encoding {
        let _encoding = CFStringEncoding(CFStringEncodings.big5.rawValue)
        let encoding = CFStringConvertEncodingToNSStringEncoding(_encoding)
        return .init(rawValue: encoding)
    }
#endif
}

/// The ^FD command defines the data string for a field.
/// The field data can be any printable character except those used as command prefixes (^ and ~).
///
/// # Field Data
///
/// In RFID printers, it can also be used to specify passwords to write to tags.
public struct FieldData: ZPLCommandConvertible {
    /// Data to be printed (all printers), or a password to be written to a RFID tag (rfid printers)
    ///
    /// Values: any data string up to 3072 bytes
    ///
    /// Default: none—a string of characters must be entered
    public var text: String
    public var command: String {
        "^FD\(text)"
    }
    
    /// Field Data.
    /// - Parameters:
    ///   - text:
    ///     Data to be printed (all printers), or a password to be written to a RFID tag (rfid printers).
    ///     * Any data string up to 3072 bytes
    public init(text: String) {
        self.text = text
    }
    
    public init(text: String, encoding: String.Encoding, indicator: Character) {
        self.text = text.data(using: encoding)?
            .map {
                String(format:"\(indicator)%02X", $0)
            }
            .joined() ?? ""
    }
}