#include <catch2/catch_test_macros.hpp>
#include "lexer.h"
#include <vector>
#include <string>

using namespace camellya;

TEST_CASE("UTF-8 string support", "[lexer][utf8]") {
    std::string source = "string s = \"你好, world\";";
    Lexer lexer(source);
    auto tokens = lexer.tokenize();

    // Expected tokens: 
    // 1. string (keyword)
    // 2. s (identifier)
    // 3. = (equal)
    // 4. "你好, world" (string literal)
    // 5. ; (semicolon)
    // 6. EOF

    REQUIRE(tokens.size() == 6);
    REQUIRE(tokens[0].type == TokenType::STRING);
    REQUIRE(tokens[1].type == TokenType::IDENTIFIER);
    REQUIRE(tokens[1].lexeme == "s");
    REQUIRE(tokens[3].type == TokenType::STRING_LITERAL);
    
    // Check value
    auto literal = std::get<std::string>(tokens[3].literal);
    REQUIRE(literal == "你好, world");

    REQUIRE(tokens[3].line == 1);
    REQUIRE(tokens[3].column == 12);
    
    REQUIRE(tokens[4].type == TokenType::SEMICOLON);
    REQUIRE(tokens[4].column == 23);
}

TEST_CASE("UTF-8 identifier support", "[lexer][utf8]") {
    std::string source = "var 变量 = 10;";
    Lexer lexer(source);
    auto tokens = lexer.tokenize();

    REQUIRE(tokens.size() == 6);
    REQUIRE(tokens[1].type == TokenType::IDENTIFIER);
    REQUIRE(tokens[1].lexeme == "变量");
    REQUIRE(tokens[1].column == 5);

    REQUIRE(tokens[2].type == TokenType::EQUAL);
    // "var " (4) + "变量" (2) + " " (1) = 7. "=" should be at column 8.
    REQUIRE(tokens[2].column == 8);
}

TEST_CASE("Unicode escape sequence support", "[lexer][utf8]") {
    std::string source = "string s = \"\\u4e2d\\u6587\";"; // "中文"
    Lexer lexer(source);
    auto tokens = lexer.tokenize();

    REQUIRE(tokens.size() == 6);
    REQUIRE(tokens[3].type == TokenType::STRING_LITERAL);
    auto literal = std::get<std::string>(tokens[3].literal);
    REQUIRE(literal == "中文");
}