/* Copyright (c) 2010-2011 mbed.org, MIT License
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this software
* and associated documentation files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all copies or
* substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
* BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/


#ifndef USBMSD_H
#define USBMSD_H

#include "USB.h"

/* These headers are included for child class. */
#include "USBEndpoints.h"
#include "USBDescriptor.h"
#include "USBDevice_Types.h"

#include "USBDevice.h"

#include "disk.h"

#include "Module.h"

/**
 * USBMSD class: generic class in order to use all kinds of blocks storage chip
 *
 * Introduction
 *
 * The USBMSD implements the MSD protocol. It permits to access a memory chip (flash, sdcard,...)
 * from a computer over USB. But this class doesn't work standalone, you need to subclass this class
 * and define virtual functions which are called in USBMSD.
 *
 * How to use this class with your chip ?
 *
 * You have to inherit and define some pure virtual functions (mandatory step):
 *   - virtual int disk_read(char * data, int block): function to read a block
 *   - virtual int disk_write(const char * data, int block): function to write a block
 *   - virtual int disk_initialize(): function to initialize the memory
 *   - virtual int disk_sectors(): return the number of blocks
 *   - virtual int disk_size(): return the memory size
 *   - virtual int disk_status(): return the status of the storage chip (0: OK, 1: not initialized, 2: no medium in the drive, 4: write protection)
 *
 * All functions names are compatible with the fat filesystem library. So you can imagine using your own class with
 * USBMSD and the fat filesystem library in the same program. Just be careful because there are two different parts which
 * will access the sd card. You can do a master/slave system using the disk_status method.
 *
 * Once these functions defined, you can call connect() (at the end of the constructor of your class for instance)
 * of USBMSD to connect your mass storage device. connect() will first call disk_status() to test the status of the disk.
 * If disk_status() returns 1 (disk not initialized), then disk_initialize() is called. After this step, connect() will collect information
 * such as the number of blocks and the memory size.
 */

class USBMSD: public USB_State_Receiver, public USB_Endpoint_Receiver, public Module {
public:

    /**
    * Constructor
    *
    * @param vendor_id Your vendor_id
    * @param product_id Your product_id
    * @param product_release Your preoduct_release
    */
    USBMSD(USB *, MSD_Disk *);

    /**
    * Connect the USB MSD device. Establish disk initialization before really connect the device.
    *
    * @returns true if successful
    */
    bool connect();

    bool USBEvent_Request(CONTROL_TRANSFER&);
    bool USBEvent_RequestComplete(CONTROL_TRANSFER&, uint8_t *, uint32_t);
    bool USBEvent_EPIn(uint8_t, uint8_t);
    bool USBEvent_EPOut(uint8_t, uint8_t);
    bool USBEvent_busReset(void);
    bool USBEvent_connectStateChanged(bool connected);
    bool USBEvent_suspendStateChanged(bool suspended);

    virtual void on_module_loaded(void);

    // USB descriptors
    usbdesc_interface MSC_Interface;
    usbdesc_endpoint  MSC_BulkOut;
    usbdesc_endpoint  MSC_BulkIn;

    usbdesc_string_l(12) MSC_Description;

    // Bulk-only CBW
    typedef struct __attribute__ ((packed)) {
        uint32_t Signature;
        uint32_t Tag;
        uint32_t DataLength;
        uint8_t  Flags;
        uint8_t  LUN;
        uint8_t  CBLength;
        uint8_t  CB[16];
    } CBW;

    // Bulk-only CSW
    typedef struct __attribute__ ((packed)) {
        uint32_t Signature;
        uint32_t Tag;
        uint32_t DataResidue;
        uint8_t  Status;
    } CSW;

private:
    // parent USB composite device manager
    USB *usb;

    // disk
    MSD_Disk *disk;

    // MSC Bulk-only Stage
    enum Stage {
        READ_CBW,     // wait a CBW
        ERROR,        // error
        PROCESS_CBW,  // process a CBW request
        SEND_CSW,     // send a CSW
        WAIT_CSW,     // wait that a CSW has been effectively sent
    };

    //state of the bulk-only state machine
    Stage stage;

    // current CBW
    CBW cbw;

    // CSW which will be sent
    CSW csw;

    // addr where will be read or written data
//     uint32_t addr;

    // transitioning to block-based logic
    uint32_t lba;
    uint16_t addr_in_block;

    // length of a reading or writing
    uint32_t length;

    // number of blocks to transfer
    uint32_t blocks;

    // memory OK (after a memoryVerify)
    bool memOK;

    // cache in RAM before writing in memory. Useful also to read a block.
    uint8_t * page;

    // USB packet buffer
    uint8_t buffer[MAX_PACKET_SIZE_EPBULK];

    uint32_t BlockSize;
//     uint32_t MemorySize;
    uint32_t BlockCount;

    void CBWDecode(uint8_t * buf, uint16_t size);
    void sendCSW (void);
    bool inquiryRequest (void);
    bool write (uint8_t * buf, uint16_t size);
    bool readFormatCapacity();
    bool readCapacity (void);
    bool infoTransfer (void);
    void memoryRead (void);
    bool modeSense6 (void);
    void testUnitReady (void);
    bool requestSense (void);
    void memoryVerify (uint8_t * buf, uint16_t size);
    void memoryWrite (uint8_t * buf, uint16_t size);
    void reset();
    void fail();
};

#endif