CLK/Storage/Disk/DiskImage/Formats/WOZ.hpp

//
//  WOZ.hpp
//  Clock Signal
//
//  Created by Thomas Harte on 23/04/2018.
//  Copyright 2018 Thomas Harte. All rights reserved.
//

#ifndef WOZ_hpp
#define WOZ_hpp

#include "../DiskImage.hpp"
#include "../../../FileHolder.hpp"
#include "../../../../Numeric/CRC.hpp"

#include <string>

namespace Storage::Disk {

/*!
	Provides a @c DiskImage containing a WOZ: a bit stream representation of a floppy.
*/
class WOZ: public DiskImage {
	public:
		WOZ(const std::string &file_name);

		// Implemented to satisfy @c DiskImage.
		HeadPosition get_maximum_head_position() final;
		int get_head_count() final;
		std::shared_ptr<Track> get_track_at_position(Track::Address address) final;
		void set_tracks(const std::map<Track::Address, std::shared_ptr<Track>> &tracks) final;
		bool get_is_read_only() final;
		bool tracks_differ(Track::Address, Track::Address) final;

	private:
		Storage::FileHolder file_;
		enum class Type {
			WOZ1, WOZ2
		} type_ = Type::WOZ1;
		bool is_read_only_ = false;
		bool is_3_5_disk_ = false;
		uint8_t track_map_[160];
		long tracks_offset_ = -1;

		std::vector<uint8_t> post_crc_contents_;
		CRC::CRC32 crc_generator;

		/*!
			Gets the in-file offset of a track.

			@returns The offset within the file of the track at @c address or @c NoSuchTrack if
				the track does not exit.
		*/
		long file_offset(Track::Address address);
		constexpr static long NoSuchTrack = 0;	// This is an offset a track definitely can't lie at.
};

}

#endif /* WOZ_hpp */