(* Implementation restrictions
       3  too many nodes in graph (>1500)              			     CRG.NewNode
       4  too many sets (ANY-symbols or SYNC symbols)     CRT.NewAnySet, 
                                                         									    CRT.ComputeSyncSet
       6  too many symbols (>300)                 				          CRT.NewSym
       7  too many character classes (>50)          			        CRT.NewClass
       9  too many conditions in generated code (>100)  	    CRX.NewCondSet
       
   Trace output (ddt settings: ${digit})
		0	Prints states of automaton
		1	Prints start symbols and followers of nonterminals (also option /s)
		2	Prints the internal graph
		3	Trace of start symbol set computation
		4	Trace of follow set computation
		5	suppresses FORWARD declarations in parser (for multipass compilers)
		6	Prints the symbol list
		7	Prints a cross reference list  (also option /x)
		8	Write statistics
==========================================================================*)
MODULE Coco;

IMPORT Oberon, Texts, CRS, CRP, CRT;

CONST minErrDist = 8;

VAR w: Texts.Writer; lastErrPos: LONGINT;


PROCEDURE Error (n: INTEGER; pos: LONGINT);
	
	PROCEDURE Msg (s: ARRAY OF CHAR);
	BEGIN Texts.WriteString(w, s)
	END Msg;
	
BEGIN
	INC(CRS.errors);
	IF pos < lastErrPos + minErrDist THEN lastErrPos := pos; RETURN END;
	lastErrPos := pos;
	Texts.WriteInt(w, pos, 3); Texts.WriteString(w, ": ");
	IF n < 200 THEN
		CASE n OF
  |  0: Msg("EOF expected")
  |  1: Msg("ident expected")
  |  2: Msg("string expected")
  |  3: Msg("number expected")
  |  4: Msg("'COMPILER' expected")
  |  5: Msg("'IMPORT' expected")
  |  6: Msg("';' expected")
  |  7: Msg("'PRODUCTIONS' expected")
  |  8: Msg("'=' expected")
  |  9: Msg("'.' expected")
  | 10: Msg("'END' expected")
  | 11: Msg("'CHARACTERS' expected")
  | 12: Msg("'TOKENS' expected")
  | 13: Msg("'PRAGMAS' expected")
  | 14: Msg("'COMMENTS' expected")
  | 15: Msg("'FROM' expected")
  | 16: Msg("'TO' expected")
  | 17: Msg("'NESTED' expected")
  | 18: Msg("'IGNORE' expected")
  | 19: Msg("'CASE' expected")
  | 20: Msg("'+' expected")
  | 21: Msg("'-' expected")
  | 22: Msg("'CHR' expected")
  | 23: Msg("'(' expected")
  | 24: Msg("')' expected")
  | 25: Msg("'ANY' expected")
  | 26: Msg("'|' expected")
  | 27: Msg("'WEAK' expected")
  | 28: Msg("'[' expected")
  | 29: Msg("']' expected")
  | 30: Msg("'{' expected")
  | 31: Msg("'}' expected")
  | 32: Msg("'SYNC' expected")
  | 33: Msg("'CONTEXT' expected")
  | 34: Msg("'<' expected")
  | 35: Msg("'>' expected")
  | 36: Msg("'(.' expected")
  | 37: Msg("'.)' expected")
  | 38: Msg("??? expected")
  | 39: Msg("invalid TokenFactor")
  | 40: Msg("invalid Factor")
  | 41: Msg("invalid Factor")
  | 42: Msg("invalid Term")
  | 43: Msg("invalid Symbol")
  | 44: Msg("invalid SimSet")
  | 45: Msg("this symbol not expected in TokenDecl")
  | 46: Msg("invalid TokenDecl")
  | 47: Msg("invalid Declaration")
  | 48: Msg("invalid Declaration")
  | 49: Msg("invalid Declaration")
  | 50: Msg("this symbol not expected in Coco")
  | 51: Msg("invalid start of the program")
		ELSE Texts.WriteString(w, "error "); Texts.WriteInt(w, n, 0)
		END
	ELSE
		CASE n OF
	  |  201: Msg("unexpected end of file");
	  |  202: Msg("string terminator not on this line");
	  |  203: Msg("a literal must not have attributes");
	  |  204: Msg("this symbol kind not allowed in production");
	  |  205: Msg("symbol declared without attributes");
	  |  206: Msg("symbol declared with attributes");
	  |  207: Msg("name declared twice");
	  |  208: Msg("this type not allowed on left side of production");
	  |  209: Msg("symbol earlier referenced without attributes");
	  | 210: Msg("symbol earlier referenced with attributes");
	  | 211: Msg("missing production for grammar name");
	  | 212: Msg("grammar symbol must not have attributes");
	  | 213: Msg("a literal must not be declared with a structure")
	  | 214: Msg("semantic action not allowed here")
	  | 215: Msg("undefined name")
	  | 216: Msg("attributes not allowed in token declaration")
	  | 217: Msg("name does not match name in heading")
	  | 220: Msg("token may be empty")
	  | 221: Msg("token must not start with an iteration")
	  | 222: Msg("only characters allowed in comment declaration")
	  | 223: Msg("only terminals may be weak")
	  | 224:
	  | 225: Msg("comment delimiter must not exceed 2 characters")
	  | 226: Msg("character set contains more than one character")
		ELSE Texts.WriteString(w, "error "); Texts.WriteInt(w, n, 0)
		END
	END;
Texts.WriteLn(w); Texts.Append(Oberon.Log, w.buf)
END Error;

PROCEDURE Options(VAR s: Texts.Scanner);
	VAR i: INTEGER;
BEGIN
	IF s.nextCh = "/" THEN Texts.Scan(s); Texts.Scan(s);
		IF s.class = Texts.Name THEN i := 0;
			WHILE s.s[i] # 0X DO
				IF CAP(s.s[i]) = "X" THEN CRT.ddt[7] := TRUE
				ELSIF CAP(s.s[i]) = "S" THEN CRT.ddt[1] := TRUE
				END;
				INC(i)
			END
		END
	END;
END Options;


PROCEDURE Compile*;
	VAR s: Texts.Scanner; src, t: Texts.Text;
		pos, beg, end, time: LONGINT; i: INTEGER;
BEGIN
	Texts.OpenScanner(s, Oberon.Par.text, Oberon.Par.pos); Texts.Scan(s);
	src := NIL; pos := 0;
	IF (s.class = Texts.Char) & (s.c = "^") THEN
		Oberon.GetSelection(t, beg, end, time);
		IF time >= 0 THEN Texts.OpenScanner(s, t, beg); Texts.Scan(s) END
	END;
	IF s.class = Texts.Name THEN
		NEW(src); Texts.Open(src, s.s);
	ELSIF (s.class = Texts.Char) & (s.c = "@") THEN
		Oberon.GetSelection(t, beg, end, time);
		IF time >= 0 THEN src := t; pos := beg; s.s := " " END
	END;
	IF src # NIL THEN
		Texts.WriteString(w, "Coco/R - Compiler-Compiler V2.2"); Texts.WriteLn(w); Texts.Append(Oberon.Log, w.buf);
		i := 0; WHILE i < 10 DO CRT.ddt[i] := FALSE; INC(i) END;
		Options(s);
		CRS.Reset(src, pos, Error); lastErrPos := -10;
		CRP.Parse
	ELSE
		INC(CRS.errors);
	END;
	IF CRS.errors # 0 THEN HALT(1) END
END Compile;

BEGIN
	Texts.OpenWriter(w)
END Coco.