/*
Copyright (c) 2018 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.

Author: Leonardo de Moura
*/
#include <utility>
#include <random>
#include <iostream>
#include <vector>
#include "util/test.h"
#include "runtime/serializer.h"
#include "runtime/sstream.h"
#include "util/object_ref.h"
#include "util/init_module.h"
using namespace lean;

#define USED(x) (void)(x)

object * f(object *) {
    std::cout << "executing f...\n";
    return box(10);
}

void tst1() {
    object_ref t(mk_thunk(alloc_closure(f, 1, 0)));
    object * r1 = thunk_get(t.raw());
    object * r2 = thunk_get(t.raw());
    std::cout << "thunk value: " << unbox(r1) << "\n";
    std::cout << "thunk value: " << unbox(r2) << "\n";
}

static unsigned g_g_counter = 0;

object * g(object *) {
    g_g_counter++;
    return box(g_g_counter);
}

void tst2() {
    object * c = alloc_closure(g, 1, 0);
    inc(c);
    object * r1 = apply_1(c, box(0));
    inc(c);
    object * r2 = apply_1(c, box(0));
    lean_assert(unbox(r1) == 1);
    lean_assert(unbox(r2) == 2);
    object_ref t(mk_thunk(c));
    object * r3 = thunk_get(t.raw());
    object * r4 = thunk_get(t.raw());
    lean_assert(unbox(r3) == 3);
    lean_assert(unbox(r4) == 3);
    USED(r1); USED(r2); USED(r3); USED(r4);
}

static unsigned g_h_counter = 0;

object * h(object *) {
    g_h_counter++;
    return box(0);
}

/* Make sure box(0) is not mistaken by cached value has not been initialized yet.

   The thunk implementation relies on the fact that nullptr is not a scalar nor a valid
   Lean object. */
void tst3() {
    object_ref t(mk_thunk(alloc_closure(h, 1, 0)));
    lean_assert(g_h_counter == 0);
    object * r3 = thunk_get(t.raw());
    lean_assert(g_h_counter == 1);
    object * r4 = thunk_get(t.raw());
    lean_assert(g_h_counter == 1);
    lean_assert(unbox(r3) == 0);
    lean_assert(unbox(r4) == 0);
    USED(r3); USED(r4);
}

object * r(object *) {
    return mk_string("hello world");
}

void tst4() {
    object_ref t(mk_thunk(alloc_closure(r, 1, 0)));
    object * r3  = thunk_get(t.raw());
    object * r4  = thunk_get(t.raw());
    lean_assert(string_eq(r3, "hello world"));
    lean_assert(string_eq(r4, "hello world"));
    USED(r3); USED(r4);
}

void tst5() {
    object_ref t(mk_thunk(alloc_closure(r, 1, 0)));
    std::ostringstream out;
    serializer s(out);
    object_ref o(mk_string("bla bla"));
    s.write_object(o.raw());
    s.write_object(t.raw());
    s.write_object(t.raw());
    std::istringstream in(out.str());
    deserializer d(in);
    d.read_object();
    object * r1 = d.read_object();
    object * r2 = d.read_object();
    lean_assert(r1 == r2);
    lean_assert(is_thunk(r1));
    object * str = thunk_get(r1);
    lean_assert(strcmp(string_data(str), "hello world") == 0);
    USED(r2); USED(str);
}

unsigned g_counter = 0;
mutex g_io_mutex;

void show_msg(char const * msg) {
    unique_lock<mutex> lock(g_io_mutex);
    std::cout << msg;
}

object * task1_fn(object *) {
    g_counter++;
    show_msg("task 1 - started\n");
    this_thread::sleep_for(std::chrono::milliseconds(100));
    show_msg("task 1 - executed\n");
    return box(10);
}

object * add_10(object * a) {
    show_msg("task 2 - started\n");
    this_thread::sleep_for(std::chrono::milliseconds(200));
    show_msg("task 2 - executed\n");
    return box(unbox(a) + 10);
}

obj_res task3_fn(obj_arg val, obj_arg) {
    show_msg("task 3 - started\n");
    this_thread::sleep_for(std::chrono::milliseconds(100));
    show_msg("task 3 - executed\n");
    return box(unbox(val)+100);
}

obj_res mk_task3_fn(obj_arg val) {
    object * c     = alloc_closure(reinterpret_cast<lean_cfun>(task3_fn), 2, 1);
    closure_set(c, 0, val);
    return mk_task(c);
}

obj_res mk_task2(b_obj_arg task1) {
    inc(task1);
    return task_map(alloc_closure(add_10, 1, 0), task1);
}

obj_res mk_task3(b_obj_arg task1) {
    inc_ref(task1);
    return task_bind(task1, alloc_closure(mk_task3_fn, 1, 0));
}

void tst6_core(object * task1) {
    object_ref task2(mk_task2(task1));
    object_ref task3(mk_task3(task1));
    std::cout << "tst6 started...\n";
    object * r1 = task_get(task2.raw());
    object * r2 = task_get(task3.raw());
    std::cout << "r1: " << unbox(r1) << "\n";
    std::cout << "r2: " << unbox(r2) << "\n";
    lean_assert(unbox(r1) == 20);
    lean_assert(unbox(r2) == 110);
}

void tst6() {
    {
        scoped_task_manager m(8);
        object_ref task1(mk_task(alloc_closure(task1_fn, 1, 0)));
        tst6_core(task1.raw());
    }
    {
        scoped_task_manager m(8);
        object_ref task1(task_pure(box(10)));
        tst6_core(task1.raw());
    }
    {
        scoped_task_manager m(8);
        object_ref task1(thunk_pure(box(10)));
        lean_assert(unbox(task_get(task1.raw())) == 10);
        lean_assert(io_has_finished_core(task1.raw()));
        tst6_core(task1.raw());
    }
    {
        scoped_task_manager m(8);
        object_ref task1(mk_thunk(alloc_closure(f, 1, 0)));
        lean_assert(io_has_finished_core(task1.raw()));
        tst6_core(task1.raw());
    }
}

obj_res task4_fn(obj_arg) {
    show_msg("task 4 started...\n");
    while (!io_check_interrupt_core()) {
        show_msg("task 4 loop...\n");
        this_thread::sleep_for(std::chrono::milliseconds(10));
    }
    show_msg("task 4 was interrupted...\n");
    return box(1);
}

void tst7() {
    scoped_task_manager m(8);
    std::cout << ">> tst7 started...\n";
    object_ref task4(mk_task(alloc_closure(task4_fn, 1, 0)));
    std::cout << "task4 has finished: " << io_has_finished_core(task4.raw()) << "\n";
    this_thread::sleep_for(std::chrono::milliseconds(100));
    show_msg("request interrupt...\n");
    io_request_interrupt_core(task4.raw());
    object * r = task_get(task4.raw());
    std::cout << "task4 has finished after get: " << io_has_finished_core(task4.raw()) << "\n";
    std::cout << "r: " << unbox(r) << "\n";
}

obj_res task5_fn(obj_arg id, obj_arg) {
    show_msg((sstream() << "task 5[" << unbox(id) << "] started \n").str().c_str());
    this_thread::sleep_for(std::chrono::milliseconds(10));
    show_msg((sstream() << "task 5[" << unbox(id) << "] finished \n").str().c_str());
    return id;
}

obj_res mk_task5(obj_arg id) {
    object * c = alloc_closure(reinterpret_cast<lean_cfun>(task5_fn), 2, 1);
    closure_set(c, 0, id);
    return mk_task(c);
}

void tst8() {
    scoped_task_manager m(8);
    std::cout << ">> tst8 started...\n";
    std::vector<object_ref> tasks;
    for (unsigned i = 0; i < 100; i++) {
        tasks.push_back(object_ref(mk_task5(box(i))));
    }
    unsigned i = 0;
    for (object_ref const & t : tasks) {
        object * r = task_get(t.raw());
        lean_assert(unbox(r) == i);
        i++;
    }
}

obj_res loop_until_interrupt_fn(obj_arg) {
    while (!io_check_interrupt_core()) {
        this_thread::sleep_for(std::chrono::milliseconds(1));
    }
    return box(0);
}

obj_res task6_fn(obj_arg) {
    show_msg("task 6 started...\n");
    this_thread::sleep_for(std::chrono::milliseconds(100));
    show_msg("task 6 done...\n");
    return box(42);
}

obj_res mk_cons(b_obj_arg h, obj_arg t) {
    object * r = alloc_cnstr(1, 2, 0);
    inc(h);
    cnstr_set(r, 0, h);
    cnstr_set(r, 1, t);
    return r;
}

void tst9() {
    scoped_task_manager m(8);
    std::cout << ">> tst9 started...\n";
    object_ref t1(mk_task(alloc_closure(loop_until_interrupt_fn, 1, 0)));
    object_ref t2(mk_task(alloc_closure(loop_until_interrupt_fn, 1, 0)));
    object_ref t3(mk_task(alloc_closure(task6_fn, 1, 0)));
    object_ref ts(mk_cons(t1.raw(), mk_cons(t2.raw(), mk_cons(t3.raw(), box(0)))));
    show_msg("invoke wait_any...\n");
    object * t = io_wait_any_core(ts.raw());
    show_msg("wait_any returned...\n");
    object * v = task_get(t);
    lean_assert(unbox(v) == 42);
    io_request_interrupt_core(t1.raw());
    io_request_interrupt_core(t2.raw());
    task_get(t1.raw());
    task_get(t2.raw());
}

void tst10() {
    scoped_task_manager m(8);
    std::cout << ">> tst10 started...\n";
    object_ref t1(mk_task(alloc_closure(task6_fn, 1, 0)));
    {
        object_ref t2(mk_task2(t1.raw()));
    }
    task_get(t1.raw());
}

void tst11() {
    std::cout << ">> tst11 started...\n";
    {
        scoped_task_manager m(2);
        std::vector<object_ref> tasks;
        for (unsigned i = 0; i < 100; i++) {
            tasks.push_back(object_ref(mk_task(alloc_closure(loop_until_interrupt_fn, 1, 0))));
        }
        this_thread::sleep_for(std::chrono::milliseconds(100));
    }
    std::cout << "tst11 done...\n";
}

static atomic<bool> g_finished;

obj_res loop_until_interrupt_fn2(obj_arg) {
    while (!io_check_interrupt_core()) {
        this_thread::sleep_for(std::chrono::milliseconds(1));
    }
    g_finished = true;
    return box(0);
}


void tst12() {
    std::cout << ">> tst12 started...\n";
    g_finished = false;
    scoped_task_manager m(8);
    {
        object_ref t(mk_task(alloc_closure(loop_until_interrupt_fn2, 1, 0)));
        this_thread::sleep_for(std::chrono::milliseconds(10));
        /* task t must be interrupted automatically */
    }
    while (g_finished) {
        this_thread::sleep_for(std::chrono::milliseconds(1));
    }
    std::cout << "tst12 done...\n";
}


static atomic<unsigned> g_task7_counter(1);

obj_res task7_fn(obj_arg val, obj_arg) {
    if (g_task7_counter % 10 == 0)
        show_msg((sstream() << "task 7[" << g_task7_counter << "]\n").str().c_str());
    g_task7_counter++;
    this_thread::sleep_for(std::chrono::milliseconds(1));
    return box(unbox(val)+1);
}

obj_res mk_task7_fn(obj_arg val) {
    object * c     = alloc_closure(reinterpret_cast<lean_cfun>(task7_fn), 2, 1);
    closure_set(c, 0, val);
    return mk_task(c);
}

obj_res mk_task7(obj_arg t) {
    return task_bind(t, alloc_closure(mk_task7_fn, 1, 0));
}

object * mul2(object * a) {
    return box(unbox(a) * 2);
}

void tst13() {
    scoped_task_manager m(8);
    std::cout << "tst13 started ...\n";
    object * curr = mk_task(alloc_closure(task1_fn, 1, 0));
    std::vector<object *> children;
    for (unsigned i = 0; i < 1000; i++) {
        curr = mk_task7(curr);
        inc(curr);
        children.push_back(task_map(alloc_closure(mul2, 1, 0), curr));
    }
    inc(curr);
    object * it = curr;
    for (unsigned i = 0; i < 10000; i++) {
        it = mk_task7(it);
    }
    dec(it); // it will force the 10000 tasks created above to die...
    object * v = task_get(curr);
    dec(curr);
    show_msg((sstream() << "v: " << unbox(v) << "\n").str().c_str());
    object * vc = task_get(children.back());
    for (object * c : children)
        dec(c);
    lean_assert(unbox(v) == 1010);
    lean_assert(unbox(vc) == 2020);
    std::cout << g_task7_counter << "\n";
}

obj_res mk_parray(unsigned n, b_obj_arg v) {
    object * r = alloc_parray(n);
    for (unsigned i = 0; i < n; i++) {
        inc(v);
        r = parray_push(r, v);
    }
    return r;
}

void tst14() {
    object * a = mk_parray(10, box(0));
    lean_assert(parray_size(a) == 10);
    lean_assert(parray_get(a, 0) == box(0));
    object * b = a;
    inc(b);
    lean_assert(get_rc(a) == 2);
    lean_assert(get_rc(b) == 2);
    a = parray_set(a, 0, box(1));
    lean_assert(a != b);
    lean_assert(get_rc(b) == 1);
    lean_assert(get_rc(a) == 2);
    lean_assert(parray_get(a, 0) == box(1));
    lean_assert(parray_get(a, 1) == box(0));
    lean_assert(parray_get(b, 0) == box(0));
    lean_assert(parray_get(a, 0) == box(1));
    inc(b);
    object * c = b;
    c = parray_push(c, box(20));
    lean_assert(parray_size(c) == 11);
    lean_assert(parray_size(a) == 10);
    lean_assert(parray_size(b) == 10);
    lean_assert(parray_get(c, 0)  == box(0));
    lean_assert(parray_get(c, 10) == box(20));
    lean_assert(parray_get(a, 0)  == box(1));
    lean_assert(parray_get(b, 0)  == box(0));
    dec_ref(a); dec_ref(b);
    lean_assert(get_rc(c) == 1);
    dec_ref(c);
}

obj_res mk_foo(unsigned n) {
    object * r = alloc_cnstr(0, 1, 0);
    cnstr_set(r, 0, box(n));
    return r;
}

unsigned foo_val(b_obj_arg v) {
    return unbox(cnstr_get(v, 0));
}

void tst15() {
    object * v1 = alloc_parray(0);
    v1 = parray_push(v1, mk_foo(2));
    v1 = parray_push(v1, mk_foo(3));
    lean_assert(foo_val(parray_get(v1, 0)) == 2);
    lean_assert(foo_val(parray_get(v1, 1)) == 3);
    object * v2 = v1;
    inc(v2);
    for (unsigned i = 0; i < 10; i++)
        v1 = parray_push(v1, mk_foo(i));
    v1 = parray_set(v1, 0, mk_foo(100));
    v1 = parray_set(v1, 1, mk_foo(100));
    lean_assert(parray_size(v2) == 2);
    lean_assert(foo_val(parray_get(v2, 0)) == 2);
    lean_assert(foo_val(parray_get(v2, 1)) == 3);
    object * v3 = v1;
    inc(v3);
    v1 = parray_pop(v1);
    v1 = parray_pop(v1);
    lean_assert(parray_size(v1) == 10);
    lean_assert(parray_size(v3) == 12);
    dec_ref(v1); dec_ref(v2);
    lean_assert(get_rc(v3) == 1);
    dec_ref(v3);
}

void driver(unsigned max_sz, unsigned max_val, unsigned num_it,
            double push_freq,
            double pop_freq,
            double set_freq,
            double copy_freq) {
    object * v1 = alloc_parray(0);
    std::vector<unsigned> v2;
    std::mt19937   rng;
    rng.seed(static_cast<unsigned int>(time(0)));
    std::uniform_int_distribution<unsigned int> uint_dist;
    std::vector<std::pair<object*, std::vector<unsigned>>> copies;
    lean_assert(get_rc(v1) == 1);
    size_t acc_sz = 0;
    for (unsigned i = 0; i < num_it; i++) {
        acc_sz += parray_size(v1);
        double f = static_cast<double>(uint_dist(rng) % 10000) / 10000.0;
        if (f < copy_freq) {
            inc_ref(v1);
            copies.emplace_back(v1, v2);
        }
        f = static_cast<double>(uint_dist(rng) % 10000) / 10000.0;
        if (f < push_freq) {
            if (parray_size(v1) < max_sz) {
                unsigned a = uint_dist(rng) % max_val;
                v1 = parray_push(v1, box(a));
                v2.push_back(a);
            }
        }
        if (parray_size(v1) > 0) {
            f = static_cast<double>(uint_dist(rng) % 10000) / 10000.0;
            if (f < pop_freq) {
                v1 = parray_pop(v1);
                v2.pop_back();
            }
        }
        if (parray_size(v1) > 0) {
            f = static_cast<double>(uint_dist(rng) % 10000) / 10000.0;
            if (f < set_freq) {
                unsigned idx = uint_dist(rng) % parray_size(v1);
                unsigned a   = uint_dist(rng) % max_val;
                v1 = parray_set(v1, idx, box(a));
                v2[idx] = a;
            }
        }
        f = static_cast<double>(uint_dist(rng) % 10000) / 10000.0;
        lean_assert(parray_size(v1) == v2.size());
        for (unsigned i = 0; i < v2.size(); i++) {
            lean_assert(unbox(parray_get(v1, i)) == v2[i]);
        }
    }
    for (std::pair<object *, std::vector<unsigned>> const & p : copies) {
        lean_assert(parray_size(p.first) == p.second.size());
        for (unsigned i = 0; i < p.second.size(); i++) {
            lean_assert(unbox(parray_get(p.first, i)) == p.second[i]);
        }
        dec_ref(p.first);
    }
    std::cout << "\n";
    std::cout << "Copies created:  " << copies.size() << "\n";
    std::cout << "Average size:    " << static_cast<double>(acc_sz) / static_cast<double>(num_it) << "\n";
    lean_assert(get_rc(v1) == 1);
    dec_ref(v1);
}

static void tst16() {
    driver(4,  32, 10000, 0.5, 0.1, 0.5, 0.1);
    driver(4,  32, 10000, 0.5, 0.1, 0.5, 0.1);
    driver(4,  32, 10000, 0.5, 0.1, 0.5, 0.5);
    driver(16, 16, 100000, 0.5, 0.5, 0.5, 0.01);
    driver(16, 16, 100000, 0.5, 0.1, 0.5, 0.01);
    driver(16, 16, 100000, 0.5, 0.6, 0.5, 0.01);
    driver(16, 16, 10000, 0.5, 0.1, 0.5, 0.0);
}

int main() {
    save_stack_info();
    initialize_util_module();
    tst1();
    tst2();
    tst3();
    tst4();
    tst5();
    tst6();
    tst7();
    tst8();
    tst9();
    tst10();
    tst11();
    tst12();
    tst13();
    tst14();
    tst15();
    tst16();
    finalize_util_module();
    return has_violations() ? 1 : 0;
}