-- BasicControl.mesa
-- edited by Brotz and Hilton, September 22, 1982 4:24 PM
-- edited by Taft, May 6, 1983 4:25 PM

DIRECTORY
BasicImpDefs,
BasicOps,
ImageDefs,
IODefs,
LaurelExecDefs,
Real,
SegmentDefs USING [memConfig],
TimeDefs,
vmD: FROM "VirtualMgrDefs";

BasicControl: PROGRAM
IMPORTS BasicImpDefs, ImageDefs, IODefs, LaurelExecDefs, Real, SegmentDefs,
TimeDefs, vmD
EXPORTS BasicImpDefs =

BEGIN
OPEN BasicImpDefs;

isProgramLine: PUBLIC BOOLEAN;

WriteHerald: PROCEDURE =
BEGIN
time: STRING ← [25];
TimeDefs.AppendDayTime[time, TimeDefs.UnpackDT[ImageDefs.BcdVersion[].time]];
IODefs.WriteLine[""L];
IODefs.WriteString["Laurel Basic of "L];
IODefs.WriteLine[time];
IODefs.WriteLine["(CTRL DEL interrupts execution. Type HELP for information.)"L];
IODefs.WriteLine[""];
END; -- of WriteHerald --

CheckConfig: PROCEDURE RETURNS [ok: BOOLEAN ← FALSE] =
BEGIN OPEN SegmentDefs, IODefs;
sorry: STRING = "Sorry, your machine is incapable of running Basic, because "L;
IF ~memConfig.useXM THEN
{WriteString[sorry]; WriteLine["there isn’t enough memory."L]; RETURN};
IF memConfig.AltoType IN [AltoI..AltoIIXM] AND memConfig.mesaMicrocodeVersion < 41 THEN
{WriteString[sorry]; WriteLine["the wrong microcode is installed."L]; RETURN};
ok ← TRUE;
END; -- CheckConfig --

-- M A I N E X E C U T I O N

IF ~CheckConfig[] THEN STOP;

START BasicScanner;
START BasicProgram;
START BasicVariable;
START BasicCommand;
START BasicInterpA;
START BasicInterpB;
START BasicParser;


LaurelExecDefs.MakeMenuCommandCallable[newMail];
LaurelExecDefs.MakeMenuCommandCallable[user];
LaurelExecDefs.MakeMenuCommandCallable[mailFile];
LaurelExecDefs.MakeMenuCommandCallable[display];
LaurelExecDefs.MakeMenuCommandCallable[delete];
LaurelExecDefs.MakeMenuCommandCallable[undelete];
LaurelExecDefs.MakeMenuCommandCallable[moveTo];
LaurelExecDefs.MakeMenuCommandCallable[copy];

WriteHerald[];

Real.InitReals[];
InitCharTable[];
InitBuiltInFunctionRegistry[];
DO
savedIndex,
programLineNumber: CARDINAL;
IF autoOn THEN OutputAutoLineNumber[];
IODefs.ReadLine[inputLine ! IODefs.Rubout => {IODefs.WriteLine[" XXX"L]; LOOP}];
inputLineIndex ← 0;
IF GetToken[] THEN
BEGIN
savedIndex ← inputLineIndex;
[isProgramLine, programLineNumber] ← TokenIsLineNumber[];
vmD.InitComposedMessage[lineCodeCm, ""L];
IF isProgramLine THEN [] ← GetToken[] ELSE savedIndex ← 0;
ParseStatement[savedIndex ! ParseErrorSignal => LOOP];
AppendByte[lineCodeCm, BasicOps.Done];
IF isProgramLine THEN
BEGIN
AllocateAndInsert[programLineNumber, savedIndex];
autoStart ← programLineNumber;
END
ELSE BEGIN
autoOn ← FALSE;
InterpretCode[lineCodeCm, 0
! QuitSignal => EXIT;
RunTimeErrorSignal, ParseErrorSignal => LOOP];
END;
END;
ENDLOOP;

VariableCleanUp[];
CommandCleanUp[];
ProgramCleanUp[];

END. -- of BasicControl --