#![feature(zero_one)]
#![feature(num_bits_bytes)]

extern crate rand;

extern crate alchemy;
extern crate sigils;



use std::thread::{Builder, JoinHandle};



const EXHAUSTIVE_RUNS: u64 = 10000u64;



macro_rules! create_thread
{
   ($thread_name: expr, $func_name: ident) =>
   {
      {
         let builder: Builder;

         builder = Builder::new().name($thread_name.to_string());
         match builder.spawn($func_name)
         {
            Ok(handle) =>
            {
               handle
            }

            Err(_) =>
            {
               panic!("Error spawning thread:  {}.", $thread_name);
            }
         }
      }
   }
}

///
macro_rules! full_check_impl
{
   ($T: ident, $read_func: ident, $write_func: ident, $numBytes: expr) =>
   {
      {
         use rand::ThreadRng;
         use rand::distributions::{IndependentSample, Range};
         use alchemy::{BigEndian, LittleEndian, Transmutable};

         let range: Range<$T>;
         let mut rng: ThreadRng;

         rng = rand::thread_rng();
         range = Range::new(std::$T::MIN, std::$T::MAX);
         for _ in 0..EXHAUSTIVE_RUNS
         {
            let val: $T;
            let final_big_val: $T;
            let final_little_val: $T;
            let mut buffer: [u8; $numBytes];

            buffer = [0u8; $numBytes];
            val = range.ind_sample(&mut rng);

            BigEndian::$write_func(&mut buffer, val);
            final_big_val = BigEndian::$read_func(&buffer);
            if final_big_val != val
            {
               panic!(false);
            }

            LittleEndian::$write_func(&mut buffer, val);
            final_little_val = LittleEndian::$read_func(&buffer);
            if final_little_val != val
            {
               panic!(false);
            }
         }

         true
      }
   }
}

///
macro_rules! full_check
{
   ($func_name: ident, $T: ident, $read_func: ident, $write_func: ident) =>
   {
      fn $func_name() -> bool
      {
         use std::$T;
         full_check_impl!($T, $read_func, $write_func, $T::BYTES)
      }
   };

   ($func_name: ident, $T: ident,
    $read_func: ident, $write_func: ident, $numBytes: expr) =>
   {
      fn $func_name() -> bool
      {
         full_check_impl!($T, $read_func, $write_func, $numBytes)
      }
   };
}

/// This should only be called by the macro below.
macro_rules! overflow_impl
{
   ($numBytes: expr, $T: ident,
    $read_func: ident, $write_func: ident) =>
   {
      use std::num::Zero;

      use alchemy::{BigEndian, LittleEndian, Transmutable};



      #[test]
      #[should_panic]
      fn read_big_endian()
      {
         let buffer: [u8; $numBytes - 1];

         buffer = [0u8; $numBytes - 1];
         BigEndian::$read_func(&buffer);
      }

      #[test]
      #[should_panic]
      fn read_little_endian()
      {
         let buffer: [u8; $numBytes - 1];

         buffer = [0u8; $numBytes - 1];
         LittleEndian::$read_func(&buffer);
      }


      #[test]
      #[should_panic]
      fn write_big_endian()
      {
         let mut buffer: [u8; $numBytes - 1];

         buffer = [0u8; $numBytes - 1];
         BigEndian::$write_func(&mut buffer, $T::zero());
      }

      #[test]
      #[should_panic]
      fn write_little_endian()
      {
         let mut buffer: [u8; $numBytes - 1];

         buffer = [0u8; $numBytes - 1];
         LittleEndian::$write_func(&mut buffer, $T::zero());
      }
   };
}

/// This macro tries to test for buffer overflow happening.
macro_rules! test_buffer_overflow
{
   ($mod_name: ident, $T: ident,
    $read_func: ident, $write_func: ident) =>
   {
      mod $mod_name
      {
         use std::$T;
         overflow_impl!($T::BYTES, $T, $read_func, $write_func);
      }
   };

   ($mod_name: ident, $T: ident,
    $read_func: ident, $write_func: ident, $numBytes: expr) =>
   {
      mod $mod_name
      {
         overflow_impl!($numBytes, $T, $read_func, $write_func);
      }
   };
}



// Test the different data types for buffer overflow.
test_buffer_overflow!(overflow_u16, u16, bytes_to_u16, u16_to_bytes);
test_buffer_overflow!(overflow_u32, u32, bytes_to_u32, u32_to_bytes);
test_buffer_overflow!(overflow_u64, u64, bytes_to_u64, u64_to_bytes);
test_buffer_overflow!(overflow_usize, usize,
                      bytes_to_usize, usize_to_bytes, 1);

test_buffer_overflow!(overflow_i16, i16, bytes_to_i16, i16_to_bytes);
test_buffer_overflow!(overflow_i32, i32, bytes_to_i32, i32_to_bytes);
test_buffer_overflow!(overflow_i64, i64, bytes_to_i64, i64_to_bytes);
test_buffer_overflow!(overflow_isize, isize,
                      bytes_to_isize, isize_to_bytes, 1);

test_buffer_overflow!(overflow_f32, f32, bytes_to_f32, f32_to_bytes, 4);
test_buffer_overflow!(overflow_f64, f64, bytes_to_f64, f64_to_bytes, 8);

// Create the exhaustive check functions for the integer types.
full_check!(check_u16, u16, bytes_to_u16, u16_to_bytes);
full_check!(check_u32, u32, bytes_to_u32, u32_to_bytes);
full_check!(check_u64, u64, bytes_to_u64, u64_to_bytes);
full_check!(check_usize, usize, bytes_to_usize, usize_to_bytes);

full_check!(check_i16, i16, bytes_to_i16, i16_to_bytes);
full_check!(check_i32, i32, bytes_to_i32, i32_to_bytes);
full_check!(check_i64, i64, bytes_to_i64, i64_to_bytes);
full_check!(check_isize, isize, bytes_to_isize, isize_to_bytes);

full_check!(check_f32, f32, bytes_to_f32, f32_to_bytes, 4);
full_check!(check_f64, f64, bytes_to_f64, f64_to_bytes, 8);


#[test]
fn exhaustive_check()
{
   let mut threads: Vec<JoinHandle<bool>>;

   threads = Vec::new();
   threads.push(create_thread!("u16", check_u16));
   threads.push(create_thread!("u32", check_u32));
   threads.push(create_thread!("u64", check_u64));
   threads.push(create_thread!("usize", check_usize));
   threads.push(create_thread!("i16", check_i16));
   threads.push(create_thread!("i32", check_i32));
   threads.push(create_thread!("i64", check_i64));
   threads.push(create_thread!("isize", check_isize));
   threads.push(create_thread!("f32", check_f32));
   threads.push(create_thread!("f64", check_f64));

   for handle in threads
   {
      let mut name: String;

      name = String::new();
      name.push_str(handle.thread().name().unwrap());
      match handle.join()
      {
         Ok(result) =>
         {
            println!("{}:  {}", name, result);
         }

         Err(_) =>
         {
            panic!("{}", name);
         }
      }
   }
}