Ben / Nujel

/* Nujel - Copyright (C) 2020-2022 - Benjamin Vincent Schulenburg
 * This project uses the MIT license, a copy should be included under /LICENSE */
#include "nujel.h"

#include "printer.h"
#include "allocation/symbol.h"
#include "reader.h"
#include "type/closure.h"
#include "type/val.h"
#include "vm/eval.h"

#include <setjmp.h>
#include <stdlib.h>

extern u8 stdlib_no_data[];

jmp_buf exceptionTarget;
lVal *exceptionValue;
int exceptionTargetDepth = 0;

bool lVerbose    = false;

/* Initialize the allocator and symbol table, needs to be called before as
 * soon as possible, since most procedures depend on it.*/
void lInit(){
	lSymbolInit();
}

/* Cause an exception, passing V directly to the closest exception handler */
NORETURN void lExceptionThrowRaw(lVal *v){
	if(exceptionTargetDepth <= 0){
		fpf(stderr,"%V",v);
		exit(201);
	}
	exceptionValue = v;
	longjmp(exceptionTarget, 1);
	while(1){}
}

/* Cause an exception, passing a list of SYMBOL, ERROR and V to the exception handler */
NORETURN void lExceptionThrowValClo(const char *symbol, const char *error, lVal *v, lClosure *c){
	lVal *l = lCons(lValLambda(c), NULL);
	l = lCons(v,l);
	l = lCons(lValString(error),l);
	l = lCons(lValKeyword(symbol),l);
	lExceptionThrowRaw(l);
}

/* Evaluate the Nujel Lambda expression and return the results */
lVal *lLambda(lClosure *c, lVal *args, lVal *lambda){
	const int SP = lRootsGet();
	lClosure *tmpc = lClosureNewFunCall(c, args, lambda);
	lVal *ret = lBytecodeEval(tmpc, lambda->vClosure->text, false);
	lRootsRet(SP);
	return ret;
}

/* Run fun with args, evaluating args if necessary  */
lVal *lApply(lClosure *c, lVal *args, lVal *fun){
	switch(fun ? fun->type : ltNoAlloc){
	case ltObject:
		if(args && args->type == ltBytecodeArr){
			return lBytecodeEval(fun->vClosure, args->vBytecodeArr, false);
		} /* fall-through */
	default:           lExceptionThrowValClo("type-error", "Can't apply to following val", fun, c);
	case ltLambda:     return lLambda(c,args,fun);
	case ltNativeFunc: return fun->vNFunc->fp(c,args);
	}
}

/* Add all the platform specific constants to C */
static void lAddPlatformVars(lClosure *c){
	lVal *valOS, *valArch;
	#if defined(__HAIKU__)
	valOS = lValSym("Haiku");
	#elif defined(__APPLE__)
	valOS =  lValSym("MacOS");
	#elif defined(__EMSCRIPTEN__)
	valOS =  lValSym("Emscripten");
	#elif defined(__MINGW32__)
	valOS =  lValSym("Windows");
	#elif defined(__MSYS__)
	valOS = lValSym("Legacy Windows");
	#elif defined(__MINIX__) || defined(__MINIX3__)
	valOS = lValSym("Minix");
	#elif defined(__linux__)
		#if defined(__UCLIBC__)
		valOS = lValSym("uClibc/Linux");
		#elif defined(__GLIBC__)
		valOS = lValSym("GNU/Linux");
		#elif defined(__BIONIC__)
		valOS = lValSym("Android");
		#else
		valOS = lValSym("musl?/Linux");
		#endif
	#elif defined(__FreeBSD__)
	valOS = lValSym("FreeBSD");
	#elif defined(__OpenBSD__)
	valOS = lValSym("OpenBSD");
	#elif defined(__NetBSD__)
	valOS = lValSym("NetBSD");
	#elif defined(__DragonFly__)
	valOS = lValSym("DragonFlyBSD");
	#elif defined(__WATCOMC__)
	valOS = lValSym("DOS");
	#else
	valOS = lValSym("Unknown");
	#endif
	lDefineVal(c, "System/OS", valOS);

	#if defined(__arm__)
	valArch = lValSym("armv7l");
	#elif defined(__aarch64__)
	valArch = lValSym("aarch64");
	#elif defined(__x86_64__) || defined(__amd64__)
	valArch = lValSym("x86_64");
	#elif defined(__i386__)
	valArch = lValSym("x86");
	#elif defined(__EMSCRIPTEN__)
	valArch = lValSym("wasm");
	#elif defined(__powerpc__)
	valArch = lValSym("powerpc");
	#elif defined(__WATCOMC__)
	valArch = lValSym("x86");
	#else
	valArch = lValSym("unknown");
	#endif
	lDefineVal(c, "System/Architecture", valArch);
}

/* Reads EXPR which should contain bytecode arrays and then evaluate them in C.
 * Mainly used for bootstrapping the stdlib and compiler out of precompiled .no
 * files. */
lClosure *lLoad(lClosure *c, const char *expr){
	lVal *v = lRead(expr);
	for(lVal *n=v; n && n->type == ltPair; n = n->vList.cdr){
		const int RSP = lRootsGet();
		lRootsValPush(n);
		lVal *car = n->vList.car;
		if((car == NULL) || (car->type != ltBytecodeArr)){
			lExceptionThrowValClo("load-error", "Can only load values of type :bytecode-arr", car, c);
		}
		lBytecodeEval(c, car->vBytecodeArr, false);
		lRootsRet(RSP);
	}
	return c;
}

/* These add all the core NFuncs, since they are only ever used within
 | lNewRoot() there is no need to export these declearations
 */
void lOperationsArithmetic (lClosure *c);
void lOperationsArray      (lClosure *c);
void lOperationsBytecode   (lClosure *c);
void lOperationsCore       (lClosure *c);
void lOperationsMath       (lClosure *c);
void lOperationsSpecial    (lClosure *c);
void lOperationsString     (lClosure *c);
void lOperationsTree       (lClosure *c);
void lOperationsVector     (lClosure *c);

/* Create a new root closure with the stdlib */
lClosure *lNewRoot(){
	lClosure *c = lClosureAlloc();
	c->parent = NULL;
	c->type = closureLet;

	lOperationsArithmetic(c);
	lOperationsMath(c);
	lOperationsArray(c);
	lOperationsBytecode(c);
	lOperationsCore(c);
	lOperationsSpecial(c);
	lOperationsString(c);
	lOperationsTree(c);
	lOperationsVector(c);

	lAddPlatformVars(c);
	return lLoad(c, (const char *)stdlib_no_data);
}

/* Return the length of the list V */
int lListLength(lVal *v){
	int i = 0;
	for(lVal *n = v;(n != NULL) && (lCar(n) != NULL); n = lCdr(n)){i++;}
	return i;
}

lVal *lCons(lVal *car, lVal *cdr){
	lVal *v = lValAlloc(ltPair);
	v->vList.car = car;
	v->vList.cdr = cdr;
	return v;
}