#include "literal.h"
#include "memory.h"

#include <stdio.h>
#include <string.h>

static void stdoutWrapper(const char* output) {
	fprintf(stdout, output);
}

void printLiteral(Literal literal) {
	printLiteralCustom(literal, stdoutWrapper);
}

void printLiteralCustom(Literal literal, void (printFn)(const char*)) {
	switch(literal.type) {
		case LITERAL_NULL:
			printFn("null");
		break;

		case LITERAL_BOOLEAN:
			printFn(AS_BOOLEAN(literal) ? "true" : "false");
		break;

		case LITERAL_INTEGER: {
			char buffer[256];
			snprintf(buffer, 256, "%d", AS_INTEGER(literal));
			printFn(buffer);
		}
		break;

		case LITERAL_FLOAT: {
			char buffer[256];
			snprintf(buffer, 256, "%g", AS_FLOAT(literal));
			printFn(buffer);
		}
		break;

		case LITERAL_STRING: {
			char buffer[256];
			snprintf(buffer, 256, "%.*s", STRLEN(literal), AS_STRING(literal));
			printFn(buffer);
		}
		break;

		case LITERAL_IDENTIFIER: {
			char buffer[256];
			snprintf(buffer, 256, "%.*s", STRLEN_I(literal), AS_IDENTIFIER(literal));
			printFn(buffer);
		}
		break;

		default:
			//should never bee seen
			fprintf(stderr, "[Internal] Unrecognized literal type in print: %d\n", literal.type);
	}
}

void freeLiteral(Literal literal) {
	if (IS_STRING(literal)) {
		FREE(char, AS_STRING(literal));
		return;
	}
}

bool _isTruthy(Literal x) {
	return (IS_NULL(x) || (IS_BOOLEAN(x) && AS_BOOLEAN(x)) || (IS_INTEGER(x) && AS_INTEGER(x) != 0) || (IS_FLOAT(x) && AS_FLOAT(x) != 0));
}

Literal _toStringLiteral(char* str) {
	return ((Literal){LITERAL_STRING, {.string.ptr = (char*)str, .string.length = strlen((char*)str)}});
}

Literal _toIdentifierLiteral(char* str) {
	return ((Literal){LITERAL_IDENTIFIER,{.identifier.ptr = (char*)str,.identifier.length = strlen((char*)str)}});
}

char* copyString(char* original, int length) {
	char* buffer = ALLOCATE(char, length + 1);
	strncpy(buffer, original, length);
	buffer[length] = '\0';
	return buffer;
}

bool literalsAreEqual(Literal lhs, Literal rhs) {
	if (lhs.type != rhs.type) {
		// ints and floats are compatible
		if ((IS_INTEGER(lhs) || IS_FLOAT(lhs)) && (IS_INTEGER(rhs) || IS_FLOAT(rhs))) {
			if (IS_INTEGER(lhs)) {
				return AS_INTEGER(lhs) + AS_FLOAT(rhs);
			}
			else {
				return AS_FLOAT(lhs) + AS_INTEGER(rhs);
			}
		}

		return false;
	}

	switch(lhs.type) {
		case LITERAL_BOOLEAN:
			return AS_BOOLEAN(lhs) == AS_BOOLEAN(rhs);

		case LITERAL_INTEGER:
			return AS_INTEGER(lhs) == AS_INTEGER(rhs);

		case LITERAL_FLOAT:
			return AS_FLOAT(lhs) == AS_FLOAT(rhs);

		case LITERAL_STRING:
			if (STRLEN(lhs) != STRLEN(rhs)) {
				return false;
			}
			return !strncmp(AS_STRING(lhs), AS_STRING(rhs), STRLEN(lhs));

		case LITERAL_IDENTIFIER:
			if (STRLEN_I(lhs) != STRLEN_I(rhs)) {
				return false;
			}
			return !strncmp(AS_IDENTIFIER(lhs), AS_IDENTIFIER(rhs), STRLEN_I(lhs));

		default:
			//should never bee seen
			fprintf(stderr, "[internal] Unrecognized literal type: %d\n", lhs.type);
			return false;
	}
}

//hash functions
static unsigned int hashString(const char* string, int length) {
	unsigned int hash = 2166136261u;

	for (int i = 0; i < length; i++) {
		hash *= string[i];
		hash *= 16777619;
	}

	return hash;
}

static unsigned int hash(unsigned int x) {
    x = ((x >> 16) ^ x) * 0x45d9f3b;
    x = ((x >> 16) ^ x) * 0x45d9f3b;
    x = (x >> 16) ^ x;
    return x;
}

int hashLiteral(Literal lit) {
	switch(lit.type) {
		case LITERAL_NULL:
			return 0;

		case LITERAL_BOOLEAN:
			return AS_BOOLEAN(lit) ? 1 : 0;

		case LITERAL_INTEGER:
			return hash((unsigned int)AS_INTEGER(lit));

		case LITERAL_FLOAT:
			return hash(*(unsigned int*)(&AS_FLOAT(lit)));

		case LITERAL_STRING:
			return hashString(AS_STRING(lit), STRLEN(lit));

		case LITERAL_IDENTIFIER:
			return hashString(AS_IDENTIFIER(lit), STRLEN_I(lit));

		default:
			//should never bee seen
			fprintf(stderr, "[Internal] Unrecognized literal type in hash: %d\n", lit.type);
			return 0;
	}
}