*------------------------------------------------------------------------
*     RECON  standard HMS reconstruction  
*    -=====-
*
*     HMS reconstruction (ignoreing the target magnetic field and vertical
*     beam offsets)
*     - reads the data from a PAW/hbook ntuple written by hms.f
*     - writtes the results to a new PAW/hbook ntuple file
*     
*     written by Markus Muehlbauer
*------------------------------------------------------------------------
      IMPLICIT NONE
      
      INTEGER   nwpawc,icycle,istat
      PARAMETER (nwpawc = 1000000)
      REAL      paw(nwpawc)
      COMMON    /pawc/paw 

      CHARACTER*8 tags(17)  
      REAL        event(17)
      CHARACTER   name*80,filename1*80,filename2*80
       
      DATA tags/'x0','dx0dz','y0','dy0dz','z0','delta0', 
     +          'x', 'dxdz', 'y', 'dydz', 'z',  
     +          'x1','dx1dz','y1','dy1dz','z1','delta1'/
      
      ! other variables
      INTEGER   i,j,cnt
       
 10   FORMAT (X,A,$)
 20   FORMAT (A)

      PRINT *,'RECON - struct simulated Gen data'
      PRINT *,'====='    
      PRINT *
      
      PRINT *
      PRINT 10,'Enter the name of the event file:            '
      READ (5,20) filename1
      PRINT 10,'Enter the name of the reconstruction matrix: '
      READ (5,20) filename2
      PRINT *  
 
      ! read the matrix
      name = filename2(:INDEX(filename2,' ')-1)//'.map'
      print *, 'Reading the reconstruction matrix '//
     >         name(:index(name,' '))
      CALL hmsInitRecon (name)
            
      ! init HBOOK
      CALL hlimit(nwpawc)
 
      ! open the data ntuple file  
      name = filename1(:INDEX(filename1,' ')-1)//'.hbook'
      print *, 'Reading the event data '//name(:index(name,' '))
      CALL hropen(20,'Input',name,' ',4096,istat)
      CALL hcdir ('//Input',' ')
      CALL hrin  (0,999999,0)
      CALL hgnpar(20,'MAIN')
      CALL hnoent(20,cnt)
       
     
      ! open the reconstructed data ntuple file
      name = filename1(:INDEX(filename1,' ')-1)//'_'//
     >       filename2(:INDEX(filename2,' ')-1)//'.hbook'
      print *, 'Writing the reconstructed data '
     >          //name(:index(name,' '))
      CALL hropen(21,'Output',name,'NX',4096,istat)
      CALL hcdir ('//Output',' ')
     
      CALL hbookn(30,'Reconstructed Events',17,'//Output',4096,tags)
      
      DO i=1,cnt
        CALL hcdir ('//Input',' ')
        CALL hgnf  (20,i,event,j)
         
        CALL hmsReconInPlane (event(7),event(12))

        CALL hcdir ('//Output',' ')
        CALL hfn   (30,event)
      ENDDO
       
      CALL hdelet(10)
      CALL hdelet(20)
      CALL hrout(0,ICYCLE,' ')
      CALL hrend('Output')
      CALL hrend('Input')         
      
      STOP
      END