!* -*- Teco -*- Library created and maintained by KMP@MC	!

!* Notes on bugs, misfeatures, etc...				!
!*								!
!*	This doesn't seem to interact very well with		!
!*	TWENEX logical devices because it does only		!
!*	textual resolution of device names			!
!*	If you use M-X Define System, you should use		!
!*	fully expanded pathnames, not logical devices, or	!
!*	you may accidentally get two copies of the same file	!
!*	in buffer. Note this is really a bug in how Teco ET	!
!*	is handled on Twenex, and is non-trivial to fix		!
!*								!
!*	Currently this is set up to handle Lisp histories. I	!
!*	haven't really figured out yet what it would take to	!
!*	make it be more general.				!

!~Filename~:! !Library to keep track of file edit histories!
HISTORY

!& Setup HISTORY Library:! !& Set up for using history editor!
m.mEdit_System_Historyu...~	    !* C-M-~ edits history !


!Edit System History:! !S Edit a system's history!
  m(m.m &_Get_File_Property)Systemf"n[7'
  "#w :i*NAS	File_has_no_associated_systemfserr '
  qMode[4			    !* q4 gets current file mode!
  f[dfile			    !* Bind default file info	!
  [5				    !* Bind q5 !
  qBuffer_Filenamesf"nu5 et5w !* Make buffer filenames be Teco defaults!
      fsdfileu5'
  "# 0u5'
  1:<erec>"e fsifileu5 '	    !* Get file truename in q5 !
  0fo..QSystem_7_History_Filef"n[8'
  "#w
    fsosteco"e !<! et 7_HISTRY'
             "#     et 7-HISTORY.TXT'
!* Experimenting for now with this not being an error... --kmp 		    !
!*    e?"n								    !
!*     :i*NHF	System_7_has_no_associated_history_filefserr '  !
    fsdfile[8'
  m(m.m &_Get_File_Property)Module[9
!* Experimenting with q5 for now ... -kmp	!
!*  qBuffer_Filenames[6 			!
  0fo..QWindow 2 Size"e	    !* If not two windows, ...	!
     fn @m(m.m^R_One_Window)    !*    make this temporary	!
     2m(m.m^R_Two_Windows)'	    !*    & enter 2-window-mode	!
  "# fn @m(m.m^R_Other_Window)  !* Else set up to return	!
     2m(m.m^R_Other_Window)'	    !*    and go to other window!
  qBuffer_Name[1		    !* Remember this buffer     !
  [Previous_Buffer		    !* good thing to bind 	!
  fn m(m.mSelect_Buffer)1 w !* Come back here 	!
  et8
  fsdfilem(m.m&_Find_File)f"nm(m.mSelect_Buffer)'
  "#w m(m.mSelect_Buffer)*History*
      fsmodified,m(m.mVisit_File)8'
  z"e				    !* If new file, ... !
   i;;;_-*-_Mode:4;_-*-
    ;;;_History_file_for_System_7.
    ;;;_Created_by_ g(fsxuname:f6) i,_ fsdatefsfdconvw iî 
   f~Mode4"n m(m.m4_Mode)'  !* Maybe set the mode	!
   m(m.m^R_Save_File)'		    !* Save out this much	!
  q..O[2			    !* Remember this buffer	!
  fn q2-q..O"e 
        fsxmodified"n 
          :i*Cfsechodisplay
          @ftReverting_history_file...
          1:<1,m(m.mRevert_File)>"e
            :i*Cfsechodisplay
            @ftHistory_file_reverted.î '
          "# @ft_(failed)'
          0fsechoactive''
     "# !"! :i*C fsechodisplay
        @ftDon't_forget_to_save_history_file_8!î  
        0fsechoactive '  
  zj fsmodified"n m(m.m^R_Save_File)'
  0,0a-"n iî '
  iî ###_ fsdatefsfdconv i_by_  g(fsxuname:f6)
  i,_re:_
  q5"n q5 fsdfile
       fsosteco"e g(fsdsname:f6) i; g(fsdfn1:f6) i_ g(fsdfn2:f6)'
       "# fsosteco-1"e i< g(fsdsname) i> g(fsdfn1)
                        i. g(fsdfn2) i. g(fsdversion) '
          "# g(fsdfile)''
       :l q9"n i_(in_module_ g9 i) ''
  "# q9"n imodule_ g9 '"# i_??_''
  i_###î 
  0fsmodified
  :i*(Editing_System_7_History)__8_[..J
  1fsmodech			    !* Say new mode line	!
  				    !* Allow editing		!
  q2-q..O"e
   fsmodified"n m(m.m^R_Save_File)''
  				    !* Return !


!& Get File Property:! !& Get property from file property list !
				    !* WARNING: Explicit qreg popping	!
qmode[0			    !* Get mode in q0			!
1,m.m&_0_Get_File_Propertyu0	    !* Get mode hook maybe		!
q0"n :m(q0(]0)) '		    !* Run mode hook or default accessor!
  "# ]0w :m(m.m&_Default_Get_File_Property) '


!& SCHEME Get File Property:! !& Scheme Hook for file properties !

:i*[2[1			    !* Get string arg in q2, bind q1	!
.:\u1 fn1j			    !* Save the cursor			!
f[vb f[vz 0,(fsz) fsbound	    !* Bind virtual buffers open	!
j :s(:"l    oPunt'		    !* Find first form			!
6 f~HERALD"n oPunt'		    !* Assure this is a HERALD		!
6c 0,1a:"b     oPunt'		    !* ditto				!
1:< .,( 0l fll r .)fsbound	    !* Bind buffer bounds narrow	!
  >"n          oPunt'		    !* ditto				!
j :< !Top!			    !* Loop over properties		!
   :@fll			    !* Find start of next expression	!
   0,1a-;"e l oTop '		    !* Ignore comments			!
   0,1a-("n @fll '		    !* Ignore atoms			!
   c @flf~2"e oWin'		    !* Check for success		!
   r fll			    !* Skip s-exp			!
 >
f~2MODULE"e 
j 1:< :@fll
      0,1a-("n 0,1a-;"n 0,1a"n 
      @flx*''' >'
0				    !* No such property found		!
!Punt!
m(m.m&_Default_Get_File_Property)2    !* Try default handler	!
!Win!
1:< 2:@fll @flx* >"n 0'	    !* Return found expression		!


!& Default Get File Property:! !& Default way to get value of file property 
String arg is the property name. The return value is a string if such
a property was found, or 0 if no such property found. !

:i*[2[1			    !* Get string arg in q2, bind q1	!
.:\u1 fn1j			    !* Save the cursor			!
f[vb f[vz 0,(fsz) fsbound	    !* Bind virtual buffers open	!
j 1:fb-*-:"l 0'		    !* Exit if no file property list	!
.,(1:fb-*-:"l 0'fkc.)fsboundwj  !* Narrow bounds to prop list	!
:s2::"l 0'		    !* Find property name if there	!
.,(:s;:"l zj'"# r' -s_ c .)x* !* Return property value as string	!


!Define System:! !S Define a system for the Edit System History macro
String args are system name and system history file!

1,fSystem:_(			    !* Get system in q1 !
5,fFilename[2)[1		    !* Get system file in q2 !
q2 m.vSystem_1_History_File	    !* Make the variable !
0				    !* Return !