# $Id: import_cell.tcl 930 2009-12-04 23:14:35Z toby $

#-------------------------------------------------
# define info used in addcmds.tcl
set description "PowderCell .CEL file"
set extensions .cel
set procname ReadPowderCellFile
#-------------------------------------------------

proc ReadPowderCellFile {filename} {
    set fp [open $filename r]
    set cell {}
    set atomlist {}
    set spg {}
    set shift {}
    set sgnum {}
    set setting {}
    set warnlist {
	3 4 5 6 7 8 10 11 12 13 14 16 17 18 19 20 21 22 23 24 25 27 32 34 35
	37 42 43 44 45 47 48 49 50 55 56 58 59 65 66 68 69 70 71 72
    }

    while {[gets $fp line] >= 0} {
	set token [lindex $line 0] 
	switch [string toupper $token] {
	    CELL {
		set cell [lrange $line 1 end]
	    }
	    RGNR {
		set sgnum [lindex $line 1]
		set setting [lindex $line 2]
		if {$setting == ""} {set setting 1}
		# note that RGNR comes at the end of the file; ignore 
		# anything beyond here
		close $fp
		global expgui
		set fp [open [file join $expgui(scriptdir) spacegrp.ref] r]
		while {[gets $fp line] >= 0} {
		    if {$sgnum == [lindex $line 1] && \
			    $setting == [lindex $line 2]} {
			set spg [lindex $line 8]
			set shift [lindex $line 9]
			break
		    }
		}
		close $fp
		break
	    }
	    default {
		set lbl [lindex $line 0]
		set type [lindex $line 1]
		# if the type is a number, convert it to an element symbol
		catch {set type [lindex {
		    dummy-entry
		    H HE LI BE B C N O F NE NA MG AL SI P S CL AR K CA SC TI V CR MN FE CO
		    NI CU ZN GA GE AS SE BR KR RB SR Y ZR NB MO TC RU RH PD AG CD IN SN SB
		    TE I XE CS BA LA CE PR ND PM SM EU GD TB DY HO ER TM YB LU HF TA W RE
		    OS IR PT AU HG TL PB BI PO AT RN FR RA AC TH PA U NP PU AM CM BK CF 
		} $type]}
		# convert  F-, K+ and  Al3+ to F, K and Al
		regsub {[1-9]*\+} $type {} type    
		regsub {[1-9]*-} $type {} type    
		lappend typelist $type
		lappend lbllist $lbl
		lappend xyzlist [lrange $line 2 4]
	    }
	}
    }
    # create the atomlist
    foreach type $typelist lbl $lbllist xyz $xyzlist {
	if {$shift == ""} {
	    set l "$lbl $xyz $type"
	} else {
	    set l $lbl
	    foreach x $xyz offset $shift {
		lappend l [expr $x + $offset]
	    }
	    lappend l $type
	}
	lappend atomlist $l
    }
    # exact spacegroup was not found
    if {$spg == ""} {
	# how did this happen
	MyMessageBox -parent . -type ok -icon error \
		-message "Error: The space group number ($sgnum) and setting ($setting) in file $filename is invalid!"
    } elseif {$shift != ""} {
	# don't have the correct setting
	MyMessageBox -parent . -type ok -icon warning \
		-message "Note: an origin shift ($shift) has been added to the coordinates to convert them to the Origin Choice 2 setting (-1 at 000)"
    }
    return "[list $spg] [list $cell] [list $atomlist]"
}