#include "threadpool/atomic_list.h"
#include "common/UnitTest.h"
#include "common/Utilities.h"
#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <string>
#include <vector>
#include <thread>
#include <chrono>
#include <functional>
#include <atomic>
#include <algorithm>



static void modify_list( AtomicList<int,1024>& list )
{
    const int N_count = 50000;
    for (int i=0; i<N_count; i++) {
        auto v1 = list.remove_first( );
        auto v2 = list.remove( [](int) { return true; } );
        auto v3 = list.remove( [](int v) { return v>=(rand()/8); } );
        auto v4 = list.remove( [](int v) { return v>=(rand()/4); } );
        auto v5 = list.remove( [](int v) { return v>=(rand()/2); } );
        if ( v1 !=-1 ) { list.insert( v1 ); }
        if ( v2 !=-1 ) { list.insert( v2 ); }
        if ( v3 !=-1 ) { list.insert( v3 ); }
        if ( v4 !=-1 ) { list.insert( v4 ); }
        if ( v5 !=-1 ) { list.insert( v5 ); }
    }
}


static bool check_list( const std::vector<int>& x, AtomicList<int,1024>& list )
{
    bool pass = list.check();
    pass = pass && (int) x.size() == list.size();
    if ( pass ) {
        for (size_t i=0; i<x.size(); i++)
            pass = pass && x[i] == list.remove( [](int) { return true; } );
    }
    // Restore the list
    for (int i=0; i<list.size(); i++)
        list.remove_first();
    for (size_t i=0; i<x.size(); i++)
        list.insert( x[i] );
    return pass;
}


static inline void clear_list(AtomicList<int,1024>& list )
{
    for (int i=0; i<list.size(); i++)
        list.remove_first();
}



/******************************************************************
* The main program                                                *
******************************************************************/
int main( int, char *[] )
{
    UnitTest ut;

    int N_threads = 8;      // Number of threads

    // Create the list
    AtomicList<int,1024> list(-1);
    if ( list.size()==0 && list.check() )
        ut.passes( "Initialize" );
    else
        ut.failure( "Initialize" );

    // Initialize the list with some empty values
    for (int i=0; i<80; i++)
        list.insert( rand() );
    list.insert( 2 );
    list.insert( 1 );
    list.insert( rand() );

    // Try to pull off a couple of values
    int v1 = list.remove( [](int a) { return a==1; } );    // Find the entry with 1
    int v2 = list.remove( [](int) { return true; } );      // Get the first entry
    int v3 = list.remove( [](int) { return false; } );     // Fail to get an entry
    if ( v1==1 && v2==2 && v3==-1 && list.size()==81 && list.check() )
        ut.passes( "Basic sanity test" );
    else
        ut.failure( "Basic sanity test" );

    // Clear the list
    while ( list.remove( [](int) { return true; } ) != -1 ) {}

    // Create a list of known values
    //std::vector<int> data0(512);
    std::vector<int> data0(5*N_threads);
    for (size_t i=0; i<data0.size(); i++)
        data0[i] = rand();
    auto data = data0;
    std::sort( data.begin(), data.end() );

    // Test the cost to insert
    int N_it = 20;
    for (int i=0; i<list.size(); i++)
        list.remove( [](int) { return true; } );
    std::chrono::duration<double> time;
    std::chrono::time_point<std::chrono::high_resolution_clock> start, stop;
    time = time.zero();
    for (int it=0; it<N_it; it++ ) {
        clear_list( list );
        start = std::chrono::high_resolution_clock::now();
        for (size_t i=0; i<data0.size(); i++)
            list.insert( data0[i] );
        stop = std::chrono::high_resolution_clock::now();
        time += ( stop - start );
    }
    printf("insert time/item = %0.0f ns\n",1e9*time.count()/(N_it*data0.size()));

    // Test the cost to remove (first)
    time = time.zero();
    for (int it=0; it<N_it; it++ ) {
        check_list( data, list );
        start = std::chrono::high_resolution_clock::now();
        for (size_t i=0; i<data0.size(); i++)
            list.remove_first( );
        stop = std::chrono::high_resolution_clock::now();
        time += ( stop - start );
    }
    printf("remove (first) time/item = %0.0f ns\n",1e9*time.count()/(N_it*data0.size()));

    // Test the cost to remove (in order)
    time = time.zero();
    for (int it=0; it<N_it; it++ ) {
        check_list( data, list );
        start = std::chrono::high_resolution_clock::now();
        for (size_t i=0; i<data0.size(); i++)
            list.remove( [](int) { return true; } );
        stop = std::chrono::high_resolution_clock::now();
        time += ( stop - start );
    }
    printf("remove (ordered) time/item = %0.0f ns\n",1e9*time.count()/(N_it*data0.size()));

    // Test the cost to remove (out order)
    time = time.zero();
    for (int it=0; it<N_it; it++ ) {
        check_list( data, list );
        start = std::chrono::high_resolution_clock::now();
        for (size_t i=0; i<data0.size(); i++) {
            int tmp = data0[i];
            list.remove( [tmp](int v) { return v==tmp; } );
        }
        stop = std::chrono::high_resolution_clock::now();
        time += ( stop - start );
    }
    printf("remove (unordered) time/item = %0.0f ns\n",1e9*time.count()/(N_it*data0.size()));

    // Read/write to the list and check the results
    int64_t N0 = list.N_remove();
    check_list( data, list );
    start = std::chrono::high_resolution_clock::now();
    modify_list( list );
    stop = std::chrono::high_resolution_clock::now();
    double time_serial = std::chrono::duration<double>(stop-start).count();
    int64_t N1 = list.N_remove();
    bool pass = check_list( data, list );
    if ( pass )
        ut.passes( "Serial get/insert" );
    else
        ut.failure( "Serial get/insert" );
    printf("serial time = %0.5f s\n",time_serial);
    printf("serial time/item = %0.0f ns\n",1e9*time_serial/(N1-N0));

    // Have multiple threads reading/writing to the list simultaneously
    std::vector<std::thread> threads( N_threads );
    start = std::chrono::high_resolution_clock::now();
    for ( int i = 0; i < N_threads; i++ )
        threads[i] = std::thread( modify_list, std::ref(list) );
    for ( int i = 0; i < N_threads; i++ )
        threads[i].join();
    stop = std::chrono::high_resolution_clock::now();
    double time_parallel = std::chrono::duration<double>(stop-start).count();
    int64_t N2 = list.N_remove();
    pass = check_list( data, list );
    if ( pass )
        ut.passes( "Parallel get/insert" );
    else
        ut.failure( "Parallel get/insert" );
    printf("parallel time = %0.5f s\n",time_parallel);
    printf("parallel time/item = %0.0f ns\n",1e9*time_parallel/(N2-N1));

    // Try to over-fill the list
    while ( !list.empty() )
        list.remove_first();
    for (int i=1; i<=list.capacity(); i++)
        list.insert( i );
    try {
        list.insert( list.capacity()+1 );
        ut.failure( "List overflow" );
    } catch (const std::exception& e) {
        ut.passes( "List overflow" );
    } catch(...) {
        ut.failure( "List overflow (unknown exception)" );
    }

    // Finished
    ut.report();
    int N_errors = static_cast<int>( ut.NumFailGlobal() );
    return N_errors;
}