#ifndef BSTEST_H
#define BSTEST_H

#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#include <functional>
#include <stdexcept>
#include "BSProtocol.h"

#if defined(ARDUINO)
#include "BSArduino.h"
#else
#include "BSStdio.h"
#endif

#ifndef BS_LINE_BUF_SIZE
#define BS_LINE_BUF_SIZE 80
#endif

namespace bs
{
typedef void(*test_case_func_t)();

class TestCase
{
public:
    TestCase(TestCase* prev, test_case_func_t func, const char* file, size_t line, const char* name, const char* desc)
        : m_func(func), m_file(file), m_line(line), m_name(name), m_desc(desc)
    {
        if (prev) {
            prev->m_next = this;
        }
    }

    void run() const
    {
        (*m_func)();
    }

    TestCase* next() const
    {
        return m_next;
    }

    const char* file() const
    {
        return m_file;
    }

    size_t line() const
    {
        return m_line;
    }

    const char* name() const
    {
        return m_name;
    }

    const char* desc() const
    {
        return (m_desc)?m_desc:"";
    }

protected:
    TestCase* m_next = nullptr;
    test_case_func_t m_func;
    const char* m_file;
    size_t m_line;
    const char* m_name;
    const char* m_desc;
};

struct Registry {
    void add(test_case_func_t func, const char* file, size_t line, const char* name, const char* desc)
    {
        TestCase* tc = new TestCase(m_last, func, file, line, name, desc);
        if (!m_first) {
            m_first = tc;
        }
        m_last = tc;
    }
    TestCase* m_first = nullptr;
    TestCase* m_last = nullptr;
};

struct Env {
    std::function<void(void)> m_check_pass;
    std::function<void(size_t)> m_check_fail;
    std::function<void(size_t)> m_fail;
    Registry m_registry;
};

extern Env g_env;

template<typename IO>
class Runner
{
    typedef Runner<IO> Tself;
public:
    Runner(IO& io) : m_io(io)
    {
        g_env.m_check_pass = std::bind(&Tself::check_pass, this);
        g_env.m_check_fail = std::bind(&Tself::check_fail, this, std::placeholders::_1);
        g_env.m_fail = std::bind(&Tself::fail, this, std::placeholders::_1);
    }

    ~Runner()
    {
        g_env.m_check_pass = 0;
        g_env.m_check_fail = 0;
        g_env.m_fail = 0;
    }

    void run()
    {
        do {
        } while(do_menu());
    }

    void check_pass()
    {
        ++m_check_pass_count;
    }

    void check_fail(size_t line)
    {
        ++m_check_fail_count;
        protocol::output_check_failure(m_io, line);
    }

    void fail(size_t line)
    {
        protocol::output_test_end(m_io, false, m_check_pass_count + m_check_fail_count, m_check_fail_count, line);
        bs::fatal();
    }

protected:
    bool do_menu()
    {
        protocol::output_menu_begin(m_io);
        int id = 1;
        for (TestCase* tc = g_env.m_registry.m_first; tc; tc = tc->next(), ++id) {
            protocol::output_menu_item(m_io, id, tc->name(), tc->desc());
        }
        protocol::output_menu_end(m_io);
        while(true) {
            int id;
            char line_buf[BS_LINE_BUF_SIZE];
            if (!protocol::input_handle(m_io, line_buf, sizeof(line_buf), id)) {
                continue;
            }
            if (id < 0) {
                return true;
            }
            TestCase* tc = g_env.m_registry.m_first;
            for (int i = 0; i != id - 1 && tc; ++i, tc = tc->next());
            if (!tc) {
                bs::fatal();
            }
            m_check_pass_count = 0;
            m_check_fail_count = 0;
            protocol::output_test_start(m_io, tc->file(), tc->line(), tc->name(), tc->desc());
            tc->run();
            bool success = m_check_fail_count == 0;
            protocol::output_test_end(m_io, success, m_check_pass_count + m_check_fail_count, m_check_fail_count);
        }
    }

protected:
    IO& m_io;
    size_t m_check_pass_count;
    size_t m_check_fail_count;
};

class AutoReg
{
public:
    AutoReg(test_case_func_t func, const char* file, size_t line, const char* name, const char* desc = nullptr)
    {
        g_env.m_registry.add(func, file, line, name, desc);
    }
};

inline void check(bool condition, size_t line)
{
    if (!condition) {
        g_env.m_check_fail(line);
    } else {
        g_env.m_check_pass();
    }
}

inline void require(bool condition, size_t line)
{
    if (!condition) {
        g_env.m_check_fail(line);
        g_env.m_fail(line);
    } else {
        g_env.m_check_pass();
    }
}

} // ::bs

#define BS_NAME_LINE2( name, line ) name##line
#define BS_NAME_LINE( name, line ) BS_NAME_LINE2( name, line )
#define BS_UNIQUE_NAME( name ) BS_NAME_LINE( name, __LINE__ )

#define TEST_CASE( ... ) \
    static void BS_UNIQUE_NAME( TEST_FUNC__ )(); \
    namespace{ bs::AutoReg BS_UNIQUE_NAME( test_autoreg__ )( &BS_UNIQUE_NAME( TEST_FUNC__ ), __FILE__, __LINE__, __VA_ARGS__ ); }\
    static void BS_UNIQUE_NAME(  TEST_FUNC__ )()

#define CHECK(condition) bs::check((condition), __LINE__)
#define REQUIRE(condition) bs::require((condition), __LINE__)
#define FAIL() bs::g_env.m_fail(__LINE__)

#define BS_ENV_DECLARE() namespace bs { Env g_env; }
#define BS_RUN(...) do { bs::IOHelper helper = bs::IOHelper(__VA_ARGS__); bs::Runner<bs::IOHelper> runner(helper); runner.run(); } while(0);

#endif //BSTEST_H