#include <gtest/gtest.h>
#include <iostream>
#include <sstream>
#include <string>
#include <vector>
#include "adapter.hpp"

class StdoutCapture {
public:
    StdoutCapture() {
        old_buf_ = std::cout.rdbuf();
        std::cout.rdbuf(buffer_.rdbuf());
    }
    ~StdoutCapture() { std::cout.rdbuf(old_buf_); }
    std::string GetOutput() const { return buffer_.str(); }
private:
    std::ostringstream buffer_;
    std::streambuf* old_buf_;
};

class CommandLineAdapterTest : public ::testing::Test {
protected:
    std::vector<char*> CreateArgv(const std::vector<std::string>& args) {
        std::vector<char*> argv;
        for (const auto& arg : args) {
            argv.push_back(const_cast<char*>(arg.c_str()));
        }
        return argv;
    }
};

TEST_F(CommandLineAdapterTest, testCommandLineAdapterNormalInput) {
    std::vector<std::string> args = {"app", "--help"};
    auto argv = CreateArgv(args);
    CommandLineAdapter adapter(static_cast<int>(args.size()), argv.data());
    CommandLineArgs result = adapter.parse();
    EXPECT_TRUE(result.show_help);
    EXPECT_FALSE(result.has_errors);
}

TEST_F(CommandLineAdapterTest, testParseConfigMissingValueException) {
    std::vector<std::string> args = {"app", "--config"};
    auto argv = CreateArgv(args);
    CommandLineAdapter adapter(static_cast<int>(args.size()), argv.data());
    CommandLineArgs result = adapter.parse();
    EXPECT_TRUE(result.has_errors);
    EXPECT_EQ(result.error_msg, "Missing value for --config");
}

TEST_F(CommandLineAdapterTest, testParseUnknownArgumentException) {
    std::vector<std::string> args = {"app", "--unknown"};
    auto argv = CreateArgv(args);
    CommandLineAdapter adapter(static_cast<int>(args.size()), argv.data());
    CommandLineArgs result = adapter.parse();
    EXPECT_TRUE(result.has_errors);
    EXPECT_EQ(result.error_msg, "Unknown argument: --unknown");
}

TEST_F(CommandLineAdapterTest, testParseMultipleFlagsNormal) {
    std::vector<std::string> args = {"app", "--config", "cfg.ini", "--version"};
    auto argv = CreateArgv(args);
    CommandLineAdapter adapter(static_cast<int>(args.size()), argv.data());
    CommandLineArgs result = adapter.parse();
    EXPECT_EQ(result.config_path, "cfg.ini");
    EXPECT_TRUE(result.show_version);
    EXPECT_FALSE(result.has_errors);
}

TEST_F(CommandLineAdapterTest, testPrintHelpSpecialScenario) {
    StdoutCapture capture;
    std::vector<std::string> args = {"app"};
    auto argv = CreateArgv(args);
    CommandLineAdapter adapter(static_cast<int>(args.size()), argv.data());
    adapter.printHelp();
    std::string output = capture.GetOutput();
    EXPECT_NE(output.find("ModularApp v1.0.0"), std::string::npos);
    EXPECT_NE(output.find("--config"), std::string::npos);
    EXPECT_NE(output.find("--help"), std::string::npos);
}

TEST_F(CommandLineAdapterTest, testPrintVersionSpecialScenario) {
    StdoutCapture capture;
    std::vector<std::string> args = {"app"};
    auto argv = CreateArgv(args);
    CommandLineAdapter adapter(static_cast<int>(args.size()), argv.data());
    adapter.printVersion();
    std::string output = capture.GetOutput();
    EXPECT_EQ(output, "ModularApp version 1.0.0\n");
}