Syntax highlighting editor

;
;Demo of a simple syntax highlighting editor!
;
;Auto-capitalizes words and sets some funky colors for numbers,
;strings and comments.
;
;Formatting is performed 'per-line', and changes in linecount are
;tracked to determine how many lines to reformat.
;
;Note: the color and formatting logic is a little convoluted in
;the interests of minimizing textarea modifications for SPEED.
;

window=CreateWindow( "Simple syntax highlighting text editor",0,0,640,480 )

textarea=CreateTextArea( 0,0,ClientWidth(window),ClientHeight(window)-96,window )
SetGadgetLayout textarea, 1,1,1,1

font=LoadFont( "lucida",20 )
SetTextAreaFont textarea,font
SetTextAreaColor textarea,0,0,0,True
SetTextAreaColor textarea,255,255,255

ActivateGadget textarea

Global output=CreateTextArea( 0,ClientHeight(window)-96,ClientWidth(window),96,window )
DisableGadget output
SetGadgetLayout output,1,1,0,1

SetTextAreaColor output,0,0,0
SetTextAreaColor output,192,192,192,True

bp$=GetEnv$("blitzpath")
tmp$=bp$+"/tmp/tmp.bb"
bcc$=bp$+"/bin/blitzcc"

Info( "Output window active!" )
Info( "blitzpath="+bp$ )

main_menu=WindowMenu( window )
file_menu=CreateMenu( "File",0,main_menu )
edit_menu=CreateMenu( "Edit",0,main_menu )
prog_menu=CreateMenu( "Program",0,main_menu )
go_menu=CreateMenu( "Go!",301,prog_menu )

UpdateWindowMenu window

HotKeyEvent 63,0,$1001,301			;F5=program->go menu item
HotKeyEvent 1,0,$803,0,0,0,0,window	;ESC=close window!

n_lines=TextAreaLen( textarea,2 )

While WaitEvent()<>$803

	Select EventID()
	Case $103	;key hit
		Notify "Bam!"
	Case $1001	;menu action
		Select EventData()
		Case 301
			t_file=WriteFile( tmp$ )
			If t_file
				WriteLine t_file,TextAreaText$( textarea )
				CloseFile t_file
				proc=CreateProcess( bcc$+" "+tmp$ )
				If proc
					While Not Eof(proc)
						ln$=ReadLine$(proc)
						If Len(ln$) Info( ln$ )
					Wend
				Else
					Info( "Error creating blitzcc process",True )
				EndIf
			Else
				Info( "Error writing tmp file",True )
			EndIf
		End Select
	Case $401	;gadget action
		Select EventSource()
		Case textarea
			;calc row and column
			row=TextAreaCursor( textarea,2 )
			col=TextAreaCursor( textarea,1 )-TextAreaChar( textarea,row )
			t_lines=0
			If EventData()=1	;modified?
			
				;work how many lines added/removed
				n=TextAreaLen( textarea,2 )
				t_lines=n-n_lines
				n_lines=n
				If t_lines<0 t_lines=0
				
				;lock textareas before big changes
				LockTextArea textarea
				
				;format the lines!!!!!
				For n=row-t_lines To row
				
					FormatLine( textarea,n )
				
				Next
				
				;unlock textarea
				UnlockTextArea textarea
				
			EndIf
			SetStatusText window,"row="+(row+1)+" col="+(col+1)+" lines="+n_lines+" chars="+TextAreaLen(textarea)+" formated="+(t_lines+1)
		End Select
	End Select
Wend

End

Function info( t$,err=False )
	If err t$="Error! - "+t$
	AddTextAreaText output,t$+Chr$(10)
End Function

;return true for digits
Function IsDigit( i$ )
	t=Asc(i$)
	Return t>=48 And t<58
End Function

;return true for alphabetic characters
Function IsAlpha( i$ )
	t=Asc(i$)
	Return (t>=65 And t<65+26) Or (t>=97 And t<97+26)
End Function

Function FormatLine( textarea,n )
	
	;line we're formatting
	ln$=TextAreaText( textarea,n,1,2 )
	
	;start-of-line character index
	sol=TextAreaChar( textarea,n )
	
	;color and format info
	fmt_ch=0:fmt_r=0:fmt_g=0:fmt_b=0:fmt_f=-1
	
	;next char to process
	ch=1
		
	While ch<=Len(ln$)

		;save char index and get next char
		t_ch=ch
		i$=Mid$(ln$,ch,1)
		
		;turn off formating flags (bold etc) by default
		f=0
		
		If IsDigit(i$)
			;Format a numeric value
			Repeat
				ch=ch+1
				If ch>Len(ln$) Exit
				i$=Mid$(ln$,ch,1)
			Until Not IsDigit(i$)
			r=255:g=0:b=192		;barf red
		Else If IsAlpha(i$)
			;Format an identifier
			z$=i$
			q$=Upper$(i$)
			Repeat
				ch=ch+1
				If ch>Len(ln$) Exit
				i$=Mid$(ln$,ch,1)
				z$=z$+i$
				q$=q$+Lower$(i$)
			Until Not IsAlpha(i$)
			If q$<>z$
				SetTextAreaText textarea,q$,sol+t_ch-1,Len(q$)
			EndIf
			r=255:g=255:b=0:f=1	;yellow, bold
		Else If i$=Chr$(34)
			;Format a string
			Repeat
				ch=ch+1
				If ch>Len(ln$) Exit
				i$=Mid$(ln$,ch,1)
			Until i$=Chr$(34)
			If i$=Chr$(34) ch=ch+1
			r=0:g=255:b=0
		Else If i$=";"
			;Format a comment
			ch=Len(ln$)+1
			r=0:g=128:b=255:f=3	;blue, bold-italic
		Else
			;Default formatting
			ch=ch+1
			r=255:g=255:b=255	;white
		EndIf
		
		;if format changed, apply previous
		If r<>fmt_r Or g<>fmt_g Or b<>fmt_b Or f<>fmt_f
			If fmt_ch
				FormatTextAreaText textarea,fmt_r,fmt_g,fmt_b,fmt_f,sol+fmt_ch-1,t_ch-fmt_ch
			EndIf
			fmt_ch=t_ch:fmt_r=r:fmt_g=g:fmt_b=b:fmt_f=f
		EndIf
	
	Wend
	
	;format to EOL
	If fmt_ch
		FormatTextAreaText textarea,fmt_r,fmt_g,fmt_b,fmt_f,sol+fmt_ch-1,ch-fmt_ch
	EndIf
	
End Function