#include <stdlib.h>
#include <stdio.h>
#include <gsos.h>
#include "driver.h"
#include "driverwrapper.h"
#include "version.h"

struct DIB dibs[NDIBS] = {0};
struct DIBList dibList = {NDIBS};

struct GSOSDP *gsosDP = (void*)0x00BD00;  /* GS/OS direct page ptr */


void InitDIBs(void) {
    for (unsigned i = 0; i < NDIBS; i++) {
        dibs[i].linkPtr = (i < NDIBS-1) ? &dibs[i+1] : NULL;
        dibs[i].entryPtr = DriverWrapper;
            /* speed-independent, block device, read allowed, removable */
        dibs[i].characteristics = 0x03A4;
        dibs[i].blockCount = 0;
        
        int nameLen = sprintf(dibs[i].devName + 1, "NETDISK%u", i+1);
        dibs[i].devName[0] = nameLen;
        for (unsigned j = nameLen + 1; j < sizeof(dibs[i].devName); j++) {
            dibs[i].devName[j] = ' ';
        }
        
        dibs[i].slotNum = 0x8003;
        dibs[i].unitNum = i+1;
        dibs[i].version = DRIVER_VERSION;
        dibs[i].deviceID = DEVICE_GENERIC_FLOPPY_DRIVE;
        
        dibList.dibPointers[i] = &dibs[i];
    }

}


#pragma databank 1
Word DriverDispatch(Word callNum, struct GSOSDP *dp) {
    Word retVal = 0;

    switch (callNum) {
    case Driver_Startup:
        gsosDP = dp;
        break;
    
    case Driver_Open:
    case Driver_Close:
        /* Only applicable to character devices, but no error for block devs */
        break;
        
    case Driver_Read:
        //TODO
        break;
        
    case Driver_Write:
        //TODO Maybe do disk-switched logic and/or block size validation?
        retVal = drvrWrtProt;
        dp->transferCount = 0;
        break;
        
    case Driver_Status:
        switch (dp->statusCode) {
        case Get_Device_Status:
            if (dp->requestCount < 2) {
                dp->transferCount = 0;
                retVal = drvrBadParm;
                break;
            }
            //TODO handle actual disk, and disk-switched logic
            /* no disk in drive, ... */
            ((DeviceStatusRec*)dp->statusListPtr)->statusWord = 0;
            if (dp->requestCount < 6) {
                dp->transferCount = 2;
                break;
            }
            ((DeviceStatusRec*)dp->statusListPtr)->numBlocks = 0;
            dp->requestCount = 6;
            break;
            
        case Get_Config_Parameters:
            if (dp->requestCount < 2) {
                dp->transferCount = 0;
                retVal = drvrBadParm;
                break;
            }
            /* config list has length 0 */
            *(Word*)dp->statusListPtr = 0;
            dp->transferCount = 2;
            break;
            
        case Get_Wait_Status:
            if (dp->requestCount != 2) {
                dp->transferCount = 0;
                retVal = drvrBadParm;
                break;
            }
            /* always in wait mode */
            *(Word*)dp->statusListPtr = 0;
            dp->transferCount = 2;
            break;
            
        case Get_Format_Options:
            /* no format options */
            dp->transferCount = 0;
            break;
            
        case Get_Partition_Map:
            /* no partition map */
            dp->transferCount = 0;
            break;
        
        default:
            dp->transferCount = 0;
            retVal = drvrBadCode;
            break;
        }
        break;
        
    case Driver_Control:
        switch (dp->controlCode) {
        case eject:
            //TODO
            break;
            
        case setConfigParameters:
            dp->transferCount = 0;
            if (dp->requestCount < 2) {
                retVal = drvrBadParm;
                break;
            }
            /* config list should be empty (zero length) */
            if (*(Word*)dp->controlListPtr != 0) {
                retVal = drvrBadParm;
                break;
            }
            break;
            
        case setWaitStatus:
            dp->transferCount = 0;
            if (dp->requestCount != 2) {
                retVal = drvrBadParm;
                break;
            }
            /* only wait mode is valid */
            if (*(Word*)dp->controlListPtr != 0) {
                retVal = drvrBadParm;
                break;
            }
            break;
            
        case resetDevice:
        case formatDevice:
        case setFormatOptions:
        case assignPartitionOwner:
        case armSignal:
        case disarmSignal:
        case setPartitionMap:
            /* do nothing, and return no error */
            dp->transferCount = 0;
            break;
            
        default:
            dp->transferCount = 0;
            retVal = drvrBadCode;
            break;
        }
        break;
        
    case Driver_Flush:
        /* Only applicable to character devices; error for block devices */
        retVal = drvrBadReq;
        break;
    
    case Driver_Shutdown:
        //TODO
        break;
    
    default:
        retVal = drvrBadReq;
        break;
    }

    return retVal;
}
#pragma databank 0