#include "stdafx.h"
#include "Emu/Memory/Memory.h"
#include "Emu/System.h"
#include "Emu/IdManager.h"
#include "Emu/SysCalls/SysCalls.h"

#include "Emu/CPU/CPUThreadManager.h"
#include "Emu/Cell/PPUThread.h"
#include "sleep_queue.h"
#include "sys_time.h"
#include "sys_mutex.h"

SysCallBase sys_mutex("sys_mutex");

s32 sys_mutex_create(vm::ptr<u32> mutex_id, vm::ptr<sys_mutex_attribute_t> attr)
{
	sys_mutex.Warning("sys_mutex_create(mutex_id=*0x%x, attr=*0x%x)", mutex_id, attr);

	LV2_LOCK;

	if (!mutex_id || !attr)
	{
		return CELL_EFAULT;
	}

	const u32 protocol = attr->protocol;

	switch (protocol)
	{
	case SYS_SYNC_FIFO: break;
	case SYS_SYNC_PRIORITY: break;
	case SYS_SYNC_PRIORITY_INHERIT: break;
	default: sys_mutex.Error("sys_mutex_create(): unknown protocol (0x%x)", protocol); return CELL_EINVAL;
	}

	const bool recursive = attr->recursive.data() == se32(SYS_SYNC_RECURSIVE);

	if ((!recursive && attr->recursive.data() != se32(SYS_SYNC_NOT_RECURSIVE)) || attr->pshared.data() != se32(0x200) || attr->adaptive.data() != se32(0x2000) || attr->ipc_key.data() || attr->flags.data())
	{
		sys_mutex.Error("sys_mutex_create(): unknown attributes (recursive=0x%x, pshared=0x%x, adaptive=0x%x, ipc_key=0x%llx, flags=0x%x)",
			attr->recursive, attr->pshared, attr->adaptive, attr->ipc_key, attr->flags);

		return CELL_EINVAL;
	}

	std::shared_ptr<mutex_t> mutex(new mutex_t(recursive, protocol, attr->name_u64));

	*mutex_id = Emu.GetIdManager().GetNewID(mutex, TYPE_MUTEX);

	return CELL_OK;
}

s32 sys_mutex_destroy(u32 mutex_id)
{
	sys_mutex.Warning("sys_mutex_destroy(mutex_id=%d)", mutex_id);

	LV2_LOCK;

	std::shared_ptr<mutex_t> mutex;

	if (!Emu.GetIdManager().GetIDData(mutex_id, mutex))
	{
		return CELL_ESRCH;
	}

	if (!mutex->owner.expired())
	{
		return CELL_EBUSY;
	}

	// assuming that the mutex is locked immediately by another waiting thread when unlocked
	if (mutex->waiters)
	{
		return CELL_EBUSY;
	}

	if (mutex->cond_count)
	{
		return CELL_EPERM;
	}

	Emu.GetIdManager().RemoveID<mutex_t>(mutex_id);

	return CELL_OK;
}

s32 sys_mutex_lock(PPUThread& CPU, u32 mutex_id, u64 timeout)
{
	sys_mutex.Log("sys_mutex_lock(mutex_id=%d, timeout=0x%llx)", mutex_id, timeout);

	const u64 start_time = get_system_time();

	LV2_LOCK;

	std::shared_ptr<mutex_t> mutex;

	if (!Emu.GetIdManager().GetIDData(mutex_id, mutex))
	{
		return CELL_ESRCH;
	}

	std::shared_ptr<CPUThread> thread = Emu.GetCPU().GetThread(CPU.GetId(), CPU_THREAD_PPU);

	if (!mutex->owner.owner_before(thread) && !thread.owner_before(mutex->owner)) // check equality
	{
		if (mutex->recursive)
		{
			if (mutex->recursive_count == 0xffffffffu)
			{
				return CELL_EKRESOURCE;
			}

			mutex->recursive_count++;

			return CELL_OK;
		}

		return CELL_EDEADLK;
	}

	// protocol is ignored in current implementation
	mutex->waiters++; assert(mutex->waiters > 0);

	while (!mutex->owner.expired())
	{
		if (timeout && get_system_time() - start_time > timeout)
		{
			mutex->waiters--; assert(mutex->waiters >= 0);
			return CELL_ETIMEDOUT;
		}

		if (Emu.IsStopped())
		{
			sys_mutex.Warning("sys_mutex_lock(id=%d) aborted", mutex_id);
			return CELL_OK;
		}

		mutex->cv.wait_for(lv2_lock, std::chrono::milliseconds(1));
	}

	mutex->owner = thread;
	mutex->waiters--; assert(mutex->waiters >= 0);

	return CELL_OK;
}

s32 sys_mutex_trylock(PPUThread& CPU, u32 mutex_id)
{
	sys_mutex.Log("sys_mutex_trylock(mutex_id=%d)", mutex_id);

	LV2_LOCK;

	std::shared_ptr<mutex_t> mutex;

	if (!Emu.GetIdManager().GetIDData(mutex_id, mutex))
	{
		return CELL_ESRCH;
	}

	std::shared_ptr<CPUThread> thread = Emu.GetCPU().GetThread(CPU.GetId());

	if (!mutex->owner.owner_before(thread) && !thread.owner_before(mutex->owner)) // check equality
	{
		if (mutex->recursive)
		{
			if (mutex->recursive_count == 0xffffffffu)
			{
				return CELL_EKRESOURCE;
			}

			mutex->recursive_count++;

			return CELL_OK;
		}

		return CELL_EDEADLK;
	}

	if (!mutex->owner.expired())
	{
		return CELL_EBUSY;
	}

	mutex->owner = thread;

	return CELL_OK;
}

s32 sys_mutex_unlock(PPUThread& CPU, u32 mutex_id)
{
	sys_mutex.Log("sys_mutex_unlock(mutex_id=%d)", mutex_id);

	LV2_LOCK;

	std::shared_ptr<mutex_t> mutex;

	if (!Emu.GetIdManager().GetIDData(mutex_id, mutex))
	{
		return CELL_ESRCH;
	}

	std::shared_ptr<CPUThread> thread = Emu.GetCPU().GetThread(CPU.GetId());

	if (mutex->owner.owner_before(thread) || thread.owner_before(mutex->owner)) // check equality
	{
		return CELL_EPERM;
	}

	if (mutex->recursive_count)
	{
		if (!mutex->recursive)
		{
			throw __FUNCTION__;
		}
		
		mutex->recursive_count--;
	}
	else
	{
		mutex->owner.reset();
		mutex->cv.notify_one();
	}

	return CELL_OK;
}