#include "test.h"
#include "token.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

/* Helper to create a test file with content */
static void write_test_file(const char* filename, const char* content) {
	FILE* f = fopen(filename, "w");
	if (f) {
		fputs(content, f);
		fclose(f);
	}
}

static void test_tokenstream_open_fail(void) {
	Buffer* buf = buffer_open_file("v0/does_not_exist.c2");
	if (buf != NULL) fail("expected NULL for non-existent file");
	
	TokenStream* ts = tokenstream_open(buf);
	if (ts != NULL) fail("expected NULL for NULL buffer");
}

static void test_tokenstream_simple_keyword(void) {
	write_test_file("v0/test_token_tmp.c2", "module");
	Buffer* buf = buffer_open_file("v0/test_token_tmp.c2");
	if (buf == NULL) fail("could not open file");

	TokenStream* ts = tokenstream_open(buf);
	if (ts == NULL) fail("could not create tokenstream");

	Token t = tokenstream_next(ts);
	if (t != TOKEN_MODULE) fail("expected TOKEN_MODULE");

	Token eof = tokenstream_next(ts);
	if (eof != -1) fail("expected EOF");

	tokenstream_close(ts);
}

static void test_tokenstream_keywords_and_symbols(void) {
	write_test_file("v0/test_token_tmp.c2", "module main; import stdio;");
	Buffer* buf = buffer_open_file("v0/test_token_tmp.c2");
	if (buf == NULL) fail("could not open file");

	TokenStream* ts = tokenstream_open(buf);
	if (ts == NULL) fail("could not create tokenstream");

	if (tokenstream_next(ts) != TOKEN_MODULE) fail("expected TOKEN_MODULE");
	if (tokenstream_next(ts) != TOKEN_IDENTIFIER) fail("expected TOKEN_IDENTIFIER (main)");
	if (tokenstream_next(ts) != TOKEN_SEMICOLON) fail("expected TOKEN_SEMICOLON");
	if (tokenstream_next(ts) != TOKEN_IMPORT) fail("expected TOKEN_IMPORT");
	if (tokenstream_next(ts) != TOKEN_IDENTIFIER) fail("expected TOKEN_IDENTIFIER (stdio)");
	if (tokenstream_next(ts) != TOKEN_SEMICOLON) fail("expected TOKEN_SEMICOLON");
	if (tokenstream_next(ts) != -1) fail("expected EOF");

	tokenstream_close(ts);
}

static void test_tokenstream_parentheses_and_brackets(void) {
	write_test_file("v0/test_token_tmp.c2", "()[]");
	Buffer* buf = buffer_open_file("v0/test_token_tmp.c2");
	if (buf == NULL) fail("could not open file");

	TokenStream* ts = tokenstream_open(buf);
	if (ts == NULL) fail("could not create tokenstream");

	if (tokenstream_next(ts) != TOKEN_PARENT_OPEN) fail("expected TOKEN_PARENT_OPEN");
	if (tokenstream_next(ts) != TOKEN_PARENT_CLOSE) fail("expected TOKEN_PARENT_CLOSE");
	if (tokenstream_next(ts) != TOKEN_BRACKET_OPEN) fail("expected TOKEN_BRACKET_OPEN");
	if (tokenstream_next(ts) != TOKEN_BRACKET_CLOSE) fail("expected TOKEN_BRACKET_CLOSE");
	if (tokenstream_next(ts) != -1) fail("expected EOF");

	tokenstream_close(ts);
}

static void test_tokenstream_comma(void) {
	write_test_file("v0/test_token_tmp.c2", "a,b,c");
	Buffer* buf = buffer_open_file("v0/test_token_tmp.c2");
	if (buf == NULL) fail("could not open file");

	TokenStream* ts = tokenstream_open(buf);
	if (ts == NULL) fail("could not create tokenstream");

	if (tokenstream_next(ts) != TOKEN_IDENTIFIER) fail("expected a");
	if (tokenstream_next(ts) != TOKEN_COMMA) fail("expected comma");
	if (tokenstream_next(ts) != TOKEN_IDENTIFIER) fail("expected b");
	if (tokenstream_next(ts) != TOKEN_COMMA) fail("expected comma");
	if (tokenstream_next(ts) != TOKEN_IDENTIFIER) fail("expected c");
	if (tokenstream_next(ts) != -1) fail("expected EOF");

	tokenstream_close(ts);
}

static void test_tokenstream_whitespace_ignored(void) {
	write_test_file("v0/test_token_tmp.c2", "  module  \n\t import  ;  ");
	Buffer* buf = buffer_open_file("v0/test_token_tmp.c2");
	if (buf == NULL) fail("could not open file");

	TokenStream* ts = tokenstream_open(buf);
	if (ts == NULL) fail("could not create tokenstream");

	if (tokenstream_next(ts) != TOKEN_MODULE) fail("expected TOKEN_MODULE");
	if (tokenstream_next(ts) != TOKEN_IMPORT) fail("expected TOKEN_IMPORT");
	if (tokenstream_next(ts) != TOKEN_SEMICOLON) fail("expected TOKEN_SEMICOLON");
	if (tokenstream_next(ts) != -1) fail("expected EOF");

	tokenstream_close(ts);
}

static void test_tokenstream_void_function_signature(void) {
	write_test_file("v0/test_token_tmp.c2", "void main()");
	Buffer* buf = buffer_open_file("v0/test_token_tmp.c2");
	if (buf == NULL) fail("could not open file");

	TokenStream* ts = tokenstream_open(buf);
	if (ts == NULL) fail("could not create tokenstream");

	if (tokenstream_next(ts) != TOKEN_VOID) fail("expected TOKEN_VOID");
	if (tokenstream_next(ts) != TOKEN_IDENTIFIER) fail("expected TOKEN_IDENTIFIER");
	if (tokenstream_next(ts) != TOKEN_PARENT_OPEN) fail("expected TOKEN_PARENT_OPEN");
	if (tokenstream_next(ts) != TOKEN_PARENT_CLOSE) fail("expected TOKEN_PARENT_CLOSE");
	if (tokenstream_next(ts) != -1) fail("expected EOF");

	tokenstream_close(ts);
}