#include "noom.h"
#include "compiler.h"
#include "helper.h"

// COMPILATION!!!!!!!!!!!!!!!!!!!
// ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣀⣴⢲⣞⣭⣟⣿⣻⣷⢶⢦⣄⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⠀⠀⠀⠀⠀⣤⣞⣵⢯⣿⣞⣷⣿⣷⣿⣿⣿⣿⣜⣦⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⠀⠀⠀⣤⣶⢿⣾⣽⣿⣿⣾⣿⣿⣿⣿⣿⣿⣿⣿⣯⣇⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⠀⡤⢿⣿⣿⣿⣿⣯⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣷⢫⡀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⢆⣴⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣯⡗⡇⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⢠⣼⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣻⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⢰⣾⣿⣿⠿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡑⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠋⠉⠀⠀⠀⠀⠘⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡷⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⠀⠀⠀⠀⠻⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⠆⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⠀⠀⠀⠀⠀⠈⠛⠻⠿⢿⣿⠟⠛⠛⠻⣿⣿⣿⣿⡿⠂⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠸⣿⣇⠀⠀⠀⠉⢿⡟⠛⠁⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢸⣿⣿⠀⠀⠀⠀⣼⣧⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣿⡇⠀⠀⠀⠀⣿⣿⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣿⠁⠀⠀⠀⢨⣿⡷⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢸⣿⠀⠀⠀⠀⠀⣿⠿⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⡀⠀⢀⠀⠀⠀⠀⠀⠀⠀⠀⢼⣿⣧⡴⢤⣶⡴⢻⡏⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠘⠛⠿⠻⠷⠾⠶⠷⠾⠶⡷⣿⣿⣀⠀⠀⠀⠀⢸⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⠀⠀⠀⠀⠀⣀⠴⠮⠃⠉⠛⢷⣦⣠⡄⠀⣸⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⠀⠀⠀⣠⠶⠘⠁⠀⠀⠀⠀⠀⠙⢮⡿⣧⢾⡟⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⠀⣤⠓⠈⠀⠀⠀⠀⠀⠀⠀⠀⠀⢀⣈⣽⡿⢿⣤⣀⡀⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⠀⠀⠀⠀⠀⠀⢀⢀⣠⣠⣴⣮⠾⠟⠋⠉⢹⠌⠈⠙⠻⢷⣶⣤⣤⣀⡀⠀⠀⠀
// ⠀⠀⠀⠀⠀⠀⠀⠀⠙⠛⠛⠉⠁⠀⠀⠀⠀⠀⠀⡘⠂⠀⠀⠀⠀⠈⠉⠛⠛⠻⠿⠷⠦
// ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣸⠁⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
// ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡘⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀ 

void noomC_compiler_init(noomC_Compiler *compiler) {
	compiler->parent = 0; // who is bro 😂✌️🥀
	
	compiler->localc = 0;
	compiler->localcap = 0;
	compiler->locals = 0;
	
	compiler->constidx = 0;
	compiler->constc = 0;
	compiler->constcap = 0;
}

noomV_String *noomV_String_alloc(noom_LuaVM *vm, const char *str, const noom_uint_t len) {
	noomV_String *s = (noomV_String*)noomV_allocObj(vm, NOOMV_OSTR, sizeof(noomV_String) + len + 1);
	if (s == 0) return 0;
	noom_memcpy(s->data, str, len);
	s->data[len] = '\0';
	return s;
}

noomV_Function *noomV_Function_alloc(noom_LuaVM *vm, const char *str, const noom_uint_t len) {
	noomV_Function *f = (noomV_Function*)noomV_allocObj(vm, NOOMV_OFUNC, sizeof(noomV_Function));
	if (f == 0) return 0;
	f->chunkname = noomV_String_alloc(vm, str, len);
	if (f->chunkname == 0) return 0;
	f->code = 0;
	f->consts = 0;
	f->protos = 0;
	f->upvals = 0;
	f->locals = 0;
	f->codesize = 0;
	f->linedefined = 0;
	f->lastlinedefined = 0;
	f->argc = 0;
	f->flags = 0;
	f->constsize = 0;
	f->protosize = 0;
	f->upvalsize = 0;
	f->localsize = 0;
	return f;
}

noomV_Table *noomV_Table_alloc(noom_LuaVM *vm) {
	noomV_Table *t = (noomV_Table *)noomV_allocObj(vm, NOOMV_OTABLE, sizeof(noomV_Table));
	if (t == 0) return 0;
	t->meta = 0;
	t->entries = 0;
	t->used = 0;
	t->len = 0;
	t->entrydata = 0;
	return t;
}

static noom_Exit noomC_emit(noomV_Function *func, const noomV_Inst inst) {
	func->code = noom_realloc(func->code, sizeof(noomV_Inst) * (func->codesize + 1));
	if (func->code == 0) return NOOM_ENOMEM;
	func->code[func->codesize++] = inst;
	return NOOM_OK;
}

static noom_Exit noomC_emit_Aus(noomV_Function *func, const noomV_Opcode op, const unsigned char a, const unsigned short us) {
	return noomC_emit(func, (noomV_Inst){.op = op, .a = a, .us = us});
}

static noom_Exit noomC_addconst(noomV_Function *func, const noomV_Value val) {
	if (func->constsize == NOOM_USHORT_MAX) return NOOM_PLEASEHELPMEIAMSCARED;
	func->consts = noom_realloc(func->consts, sizeof(noomV_Value) * (func->constsize + 1));
	if (func->consts == 0) return NOOM_ENOMEM;
	func->consts[func->constsize++] = val;
	return NOOM_OK;
}

static noom_Exit noomC_addconst_nil(noomV_Function *func) {
	return noomC_addconst(func, (noomV_Value){.tag = NOOMV_VNIL, .autoclose = 0, .isptr = 0});
}

static noom_Exit noomC_addconst_bool(noomV_Function *func, const noom_bool_t b) {
	return noomC_addconst(func, (noomV_Value){.tag = NOOMV_VBOOL, .autoclose = 0, .isptr = 0, .boolean =  b});
}

static noomL_Token noomC_token_at(const noomP_Parser *parser, noom_uint_t offset) {
	noomL_Token token;
	noomL_lex(parser->code, offset, &token, parser->version);
	return token;
}

static noom_Exit noomC_compile_expr(noom_LuaVM *vm, const noomC_Compiler *compiler, const noomP_Parser *parser, noomV_Function *func, const noomP_Node *node) {
	if (node->type == NOOMP_NODE_NILLITERAL) {
		noom_Exit result = noomC_addconst_nil(func);
		if (result != NOOM_OK) return result;
		result = noomC_emit_Aus(func, NOOMV_INSTR_LOADC, compiler->curstack, func->constsize - 1);
		if (result != NOOM_OK) return result;
		return NOOM_OK;
	}
	if (node->type == NOOMP_NODE_BOOLEANLITERAL) {
		noomL_Token bool_token = noomC_token_at(parser, node->source_offset);
		noom_bool_t val = noom_memeq(parser->code + bool_token.offset, bool_token.length, "true", 4);
		noom_Exit result = noomC_addconst_bool(func, val);
		if (result != NOOM_OK) return result;
		result = noomC_emit_Aus(func, NOOMV_INSTR_LOADC, compiler->curstack, func->constsize - 1);
		if (result != NOOM_OK) return result;
		return NOOM_OK;
	}
	if (node->type == NOOMP_NODE_NUMBERLITERAL) {
		return NOOM_PLEASEHELPMEIAMSCARED; // 😭😭😭😭😭😭😭😭
	}
	if (node->type == NOOMP_NODE_STRINGLITERAL) {
		return NOOM_IAMNOTSCAREDJUSTLAZYTHISTIME;
	}
	return NOOM_EINTERNAL; // Idk what else I forgot
}

static noom_Exit noomC_add_stuff_to_function(noom_LuaVM *vm, noomC_Compiler *compiler, const noomP_Parser *parser, noomV_Function *func, const noomP_Node *node);

static noom_Exit noomC_compile_block(noom_LuaVM *vm, noomC_Compiler *compiler, const noomP_Parser *parser, noomV_Function *func, const noomP_Node *node) {
	noom_Exit r = NOOM_OK;
	for (noom_uint_t i = 0; i < node->subnodec; i++) {
		r = noomC_add_stuff_to_function(vm, compiler, parser, func, node->subnodes[i]);
		if (r != NOOM_OK) break;
	}
	return r;
}

// They say you use only 10% of your brain
// Keep it
// If you think too much you will get headaches

// I remember atom said there is a memory leak somewhere but I don't rememeememember where uhhhhhhhhhhhhhhhhh
static noom_Exit noomC_add_stuff_to_function(noom_LuaVM *vm, noomC_Compiler *compiler, const noomP_Parser *parser, noomV_Function *func, const noomP_Node *node) {
	// local name <attr> = expression i think
	if (node->type == NOOMP_NODE_LOCALDECLARATION) {
		if (node->subnodec != 1 && node->subnodec != 2) return NOOM_EINTERNAL;

		const noomP_Node *varname_node = node->subnodes[0];
		if (varname_node->type != NOOMP_NODE_ASSIGNPLACE) return NOOM_EINTERNAL;

		noomC_Local local;
		local.startpc = func->codesize;
		local.endpc = 0;
		local.dropped = 0; // FIXME?
		local.close = 0;
		local.constant = 0;
		local.name = noom_strndup(parser->code + varname_node->source_offset, varname_node->source_offset);

		for (noom_uint_t i = 0; i < varname_node->subnodec; i++) {
			if (varname_node->subnodes[i]->type != NOOMP_NODE_ATTRIBUTE) return NOOM_EINTERNAL;
			
			noomL_Token attr_token = noomC_token_at(parser, varname_node->subnodes[i]->source_offset);
			const char *ap = parser->code + attr_token.offset;
			noom_uint_t al = attr_token.length;
			if (noom_memeq(ap, al, "close", 5)) {
				if (local.close) return NOOM_EINTERNAL;
				local.close = 1;
			}
			else if (noom_memeq(ap, al, "const", 5)) {
				if (local.constant) return NOOM_EINTERNAL;
				local.constant = 1;
			}
			else {
				return NOOM_EINTERNAL;
			}
		}

		const unsigned destination = compiler->curstack;
		if (compiler->curstack++ == NOOM_MAXSTACK) return NOOM_ENOSTACK;

		if (node->subnodec == 1) {
			// according to atom this should be nil
			const unsigned short constptr = func->constsize;
			const noom_Exit result = noomC_addconst_nil(func);
			if (result != NOOM_OK) return result;
			if (noomC_emit_Aus(func, NOOMV_INSTR_LOADC, destination, constptr) < 0) return NOOM_ENOMEM;
		}
		else {
			const noomP_Node *value_node = node->subnodes[1];
			const unsigned saved = compiler->curstack;
			compiler->curstack = destination;
			const noom_Exit r = noomC_compile_expr(vm, compiler, parser, func, value_node);
			if (r != NOOM_OK) return r;
			compiler->curstack = saved;
		}

		compiler->locals = noom_realloc(compiler->locals, sizeof(noomC_Local) * (compiler->localc + 1));
		if (compiler->locals == 0) return NOOM_ENOMEM;
		compiler->locals[compiler->localc++] = local;
		// I guess???????
		if (compiler->localc > compiler->localcap) compiler->localcap = compiler->localc;

		return NOOM_OK;
	}

	// local function name(...) ... end
	if (node->type == NOOMP_NODE_LOCALFUNCTIONDECLARATION) {
		if (node->subnodec != 3) return NOOM_EINTERNAL;
		// Funny staircase huh
		const noomP_Node *varname_node = node->subnodes[0];
		const noomP_Node *params_node = node->subnodes[1];
		const noomP_Node *block_node = node->subnodes[2];
		if (varname_node->type     != NOOMP_NODE_VARNAME) return NOOM_EINTERNAL;
		if (params_node->type     != NOOMP_NODE_FUNCTIONPARAMETERS) return NOOM_EINTERNAL;
		if (block_node->type     != NOOMP_NODE_BLOCK) return NOOM_EINTERNAL;

		const noomL_Token name_token = noomC_token_at(parser, varname_node->source_offset);
		noomV_Function *proto = noomV_Function_alloc(vm, parser->code + name_token.offset, name_token.length);
		if (proto == 0) return NOOM_ENOMEM;

		proto->argc = (unsigned char)params_node->subnodec;

		noomC_Compiler child;
		noomC_compiler_init(&child);
		child.parent = compiler; // Is this correct????? Is this correct????????????????? It probably is
		child.curstack = proto->argc;

		const noom_Exit result = noomC_compile_block(vm, &child, parser, proto, block_node);
		if (result != NOOM_OK) return result;

		func->protos = noom_realloc(func->protos, sizeof(noomV_Function *) * (func->protosize + 1));
		if (func->protos == 0) return NOOM_ENOMEM;
		func->protos[func->protosize++] = proto;

		// I think something should be here but idfk what
		// TODO
		noomC_emit_Aus(func, NOOMV_INSTR_NOP, 0, 0);
		
		return NOOM_OK;
	}

	// TODO
	if (node->type == NOOMP_NODE_RETURN) {
		noomC_emit_Aus(func, NOOMV_INSTR_NOP, 0, 0);
		return NOOM_OK;
	}

	if (node->type == NOOMP_NODE_DOBLOCK || node->type == NOOMP_NODE_BLOCK) {
		return noomC_compile_block(vm, compiler, parser, func, node);
	}

	return NOOM_EINTERNAL;
}

noom_Exit noomC_compile(noom_LuaVM *vm, const noomP_Parser *parser, const noomP_Node *node) {
	if (node->type != NOOMP_NODE_PROGRAM) return NOOM_EINTERNAL;
	
	noomV_Function* program = noomV_Function_alloc(vm, "main", 4);
	
	noomC_Compiler compiler;
	noomC_compiler_init(&compiler);
	
	return noomC_compile_block(vm, &compiler, parser, program, node);
}