! perfiles.f90
! module in which all load from .per file routines are held
! contains: LoadPER etc

module LoadPerFiles

use FileNames

implicit none

contains

!*******************************************************************************
! find out dimensions of arrays to specify for LoadPer

subroutine PreLoadPer (CallFile,YearN)

character (len=80), intent(inout)	:: CallFile	! can be blank
integer, intent(out)			:: YearN

integer :: VariCode,HeaderN
character (len=20) :: LineFormat

CallFile = LoadPath (CallFile,".per")
call LoadPERHeaders (CallFile,VariCode,HeaderN,LineFormat,YearN=YearN)

end subroutine PreLoadPer

!*******************************************************************************
! call PreLoadPer first, alloc arrays, then call this
! load .per file

subroutine LoadPer (CallFile,VariCode,YearAD,Monthly,Seasonal,Annual,Silent)

real, pointer, dimension (:,:)		:: Monthly, Seasonal
real, pointer, dimension (:)		:: Annual

integer, pointer, dimension (:) 	:: YearAD

integer, intent (in), optional		:: Silent

integer, intent (out)			:: VariCode

character (len=80), intent(in)		:: CallFile	! can be blank

real, parameter :: MissVal = -999.0

integer :: ReadStatus, AllocStat
integer :: YearN, MonthN, HeaderN, SeasonN
integer :: XYear, XMonth, XHeader, XSeason
integer :: TimeCode, LineYear

character (len=80) :: LoadFile, Trash
character (len=20) :: LineFormat
character (len= 4) :: Suffix

!***************************************

call LoadPerHeaders (CallFile,VariCode,HeaderN,LineFormat,YearAD=YearAD)

YearN   = size (YearAD)
MonthN  = 12
SeasonN = 4

open (2, file=CallFile, status="old", access="sequential", form="formatted", action="read")

do XHeader = 1, HeaderN  
  read (2,*), Trash
end do
  
do XYear = 1, YearN
  read (2,LineFormat), LineYear, (Monthly(XYear,XMonth), XMonth=1,12), &
  		(Seasonal(XYear,XSeason), XSeason=1,4), Annual(XYear)
end do
  
close (2)

end subroutine LoadPer

!*******************************************************************************
! load headers for .per data files
! call twice, first with YearN, then alloc YearAD, then call again with YearAD

subroutine LoadPerHeaders (FileName,VariCode,HeaderN,LineFormat,YearAD,YearN)

integer,dimension (:),pointer,optional 	:: YearAD	

integer, intent (out) 			:: HeaderN,VariCode		! -1=min, 0=mean, 1=max, 2=sum
integer, intent (out), optional 	:: YearN

character (len=80), intent (in) 	:: FileName
character (len=20), intent (out) 	:: LineFormat

real, parameter :: MissVal = -999.0

integer :: Year0, Year1, AllocStat, XYear

character (len=80) :: LoadName, Trash
character (len=20) :: Gambit
character (len=8)  :: TimePeriod, Variable 

!***************************************

open (1, file=FileName, status="old", action="read")

read (1,"(a20)"), Gambit

if      (Gambit.EQ."Tyndall Centre file ") then
  HeaderN = 4
  read (1,"(a36,a8,a1,a8)"), Trash, TimePeriod, Trash, Variable		! time period and variable
  read (1,"(a9,i4,a1,i4,a36,a20)"), Trash, Year0, Trash, Year1, Trash, LineFormat	
else if (Gambit.EQ."A Tyndall Centre fil") then
  HeaderN = 15
  read (1,"(a36,a8,a1,a8)"), Trash, TimePeriod, Trash, Variable		! time period and variable
  read (1,"(a9,i4,a1,i4,a36,a20)"), Trash, Year0, Trash, Year1, Trash, LineFormat	
else if (Gambit.EQ."Monthly, seasonal, a") then
  HeaderN = 20
  read (1,*), Trash
  read (1,*), Trash
  read (1,"(a9,i4,a1,i4,a36,a20)"), Trash, Year0, Trash, Year1, Trash, LineFormat  	
end if
						
close (1)

if      (trim(Variable).EQ."Min") then
  VariCode = -1
else if (trim(Variable).EQ."Mean") then
  VariCode =  0
else if (trim(Variable).EQ."Max") then
  VariCode =  1
else if (trim(Variable).EQ."Sum") then
  VariCode =  2
else
  VariCode = MissVal
end if

if      (present(YearN))  then
 YearN = Year1 - Year0 + 1
else if (present(YearAD)) then
 do XYear = 1, (Year1 - Year0 + 1)
  YearAD (XYear) = XYear + Year0 - 1
 end do
end if

end subroutine LoadPerHeaders

!*******************************************************************************

end module LoadPerFiles