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

#include "Emu/Cell/ErrorCodes.h"
#include "Emu/Cell/PPUThread.h"
#include "sys_ppu_thread.h"
#include "sys_event.h"
#include "sys_mmapper.h"

LOG_CHANNEL(sys_ppu_thread);

void _sys_ppu_thread_exit(ppu_thread& ppu, u64 errorcode)
{
	vm::temporary_unlock(ppu);

	sys_ppu_thread.trace("_sys_ppu_thread_exit(errorcode=0x%llx)", errorcode);

	ppu.state += cpu_flag::exit;

	// Get joiner ID
	const u32 jid = ppu.joiner.fetch_op([](u32& value)
	{
		if (value == 0)
		{
			// Joinable, not joined
			value = -3;
		}
		else if (value != -1)
		{
			// Joinable, joined
			value = -2;
		}

		// Detached otherwise
	});

	if (jid == -1)
	{
		// Detach detached thread, id will be removed on cleanup
		static_cast<named_thread<ppu_thread>&>(ppu) = thread_state::detached;
	}
	else if (jid != 0)
	{
		std::lock_guard lock(id_manager::g_mutex);

		// Schedule joiner and unqueue
		lv2_obj::awake(*idm::check_unlocked<named_thread<ppu_thread>>(jid), -2);
	}

	// Unqueue
	lv2_obj::sleep(ppu);

	// Remove suspend state (TODO)
	ppu.state -= cpu_flag::suspend;
}

void sys_ppu_thread_yield(ppu_thread& ppu)
{
	sys_ppu_thread.trace("sys_ppu_thread_yield()");

	lv2_obj::awake(ppu, -4);
}

error_code sys_ppu_thread_join(ppu_thread& ppu, u32 thread_id, vm::ptr<u64> vptr)
{
	vm::temporary_unlock(ppu);

	sys_ppu_thread.trace("sys_ppu_thread_join(thread_id=0x%x, vptr=*0x%x)", thread_id, vptr);

	const auto thread = idm::get<named_thread<ppu_thread>>(thread_id, [&](ppu_thread& thread) -> CellError
	{
		CellError result = thread.joiner.atomic_op([&](u32& value) -> CellError
		{
			if (value == -3)
			{
				value = -2;
				return CELL_EBUSY;
			}

			if (value == -2)
			{
				return CELL_ESRCH;
			}

			if (value)
			{
				return CELL_EINVAL;
			}

			// TODO: check precedence?
			if (&ppu == &thread)
			{
				return CELL_EDEADLK;
			}

			value = ppu.id;
			return {};
		});

		if (!result)
		{
			lv2_obj::sleep(ppu);
		}

		return result;
	});

	if (!thread)
	{
		return CELL_ESRCH;
	}

	if (thread.ret && thread.ret != CELL_EBUSY)
	{
		return thread.ret;
	}

	// Wait for cleanup
	(*thread.ptr)();

	// Get the exit status from the register
	if (vptr)
	{
		if (ppu.test_stopped())
		{
			return 0;
		}

		*vptr = thread->gpr[3];
	}

	// Cleanup
	idm::remove<named_thread<ppu_thread>>(thread->id);
	return CELL_OK;
}

error_code sys_ppu_thread_detach(u32 thread_id)
{
	sys_ppu_thread.trace("sys_ppu_thread_detach(thread_id=0x%x)", thread_id);

	const auto thread = idm::check<named_thread<ppu_thread>>(thread_id, [&](ppu_thread& thread) -> CellError
	{
		return thread.joiner.atomic_op([&](u32& value) -> CellError
		{
			if (value == -3)
			{
				value = -2;
				return CELL_EAGAIN;
			}

			if (value == -2)
			{
				return CELL_ESRCH;
			}

			if (value == -1)
			{
				return CELL_EINVAL;
			}

			if (value)
			{
				return CELL_EBUSY;
			}

			value = -1;
			return {};
		});
	});

	if (!thread)
	{
		return CELL_ESRCH;
	}

	if (thread.ret && thread.ret != CELL_EAGAIN)
	{
		return thread.ret;
	}

	if (thread.ret == CELL_EAGAIN)
	{
		idm::remove<named_thread<ppu_thread>>(thread_id);
	}

	return CELL_OK;
}

void sys_ppu_thread_get_join_state(ppu_thread& ppu, vm::ptr<s32> isjoinable)
{
	sys_ppu_thread.trace("sys_ppu_thread_get_join_state(isjoinable=*0x%x)", isjoinable);

	*isjoinable = ppu.joiner != -1;
}

error_code sys_ppu_thread_set_priority(ppu_thread& ppu, u32 thread_id, s32 prio)
{
	sys_ppu_thread.trace("sys_ppu_thread_set_priority(thread_id=0x%x, prio=%d)", thread_id, prio);

	if (prio < 0 || prio > 3071)
	{
		return CELL_EINVAL;
	}

	const auto thread = idm::check<named_thread<ppu_thread>>(thread_id, [&](ppu_thread& thread)
	{
		if (thread.prio != prio && thread.prio.exchange(prio) != prio)
		{
			lv2_obj::awake(thread, prio);
		}
	});

	if (!thread)
	{
		return CELL_ESRCH;
	}

	return CELL_OK;
}

error_code sys_ppu_thread_get_priority(u32 thread_id, vm::ptr<s32> priop)
{
	sys_ppu_thread.trace("sys_ppu_thread_get_priority(thread_id=0x%x, priop=*0x%x)", thread_id, priop);

	const auto thread = idm::check<named_thread<ppu_thread>>(thread_id, [&](ppu_thread& thread)
	{
		*priop = thread.prio;
	});

	if (!thread)
	{
		return CELL_ESRCH;
	}

	return CELL_OK;
}

error_code sys_ppu_thread_get_stack_information(ppu_thread& ppu, vm::ptr<sys_ppu_thread_stack_t> sp)
{
	sys_ppu_thread.trace("sys_ppu_thread_get_stack_information(sp=*0x%x)", sp);

	sp->pst_addr = ppu.stack_addr;
	sp->pst_size = ppu.stack_size;

	return CELL_OK;
}

error_code sys_ppu_thread_stop(u32 thread_id)
{
	sys_ppu_thread.todo("sys_ppu_thread_stop(thread_id=0x%x)", thread_id);

	const auto thread = idm::get<named_thread<ppu_thread>>(thread_id);

	if (!thread)
	{
		return CELL_ESRCH;
	}

	return CELL_OK;
}

error_code sys_ppu_thread_restart(u32 thread_id)
{
	sys_ppu_thread.todo("sys_ppu_thread_restart(thread_id=0x%x)", thread_id);

	const auto thread = idm::get<named_thread<ppu_thread>>(thread_id);

	if (!thread)
	{
		return CELL_ESRCH;
	}

	return CELL_OK;
}

error_code _sys_ppu_thread_create(vm::ptr<u64> thread_id, vm::ptr<ppu_thread_param_t> param, u64 arg, u64 unk, s32 prio, u32 _stacksz, u64 flags, vm::cptr<char> threadname)
{
	sys_ppu_thread.warning("_sys_ppu_thread_create(thread_id=*0x%x, param=*0x%x, arg=0x%llx, unk=0x%llx, prio=%d, stacksize=0x%x, flags=0x%llx, threadname=%s)",
		thread_id, param, arg, unk, prio, _stacksz, flags, threadname);

	if (prio < 0 || prio > 3071)
	{
		return CELL_EINVAL;
	}

	if ((flags & 3) == 3) // Check two flags: joinable + interrupt not allowed
	{
		return CELL_EPERM;
	}

	// Compute actual stack size and allocate
	const u32 stack_size = _stacksz >= 4096 ? ::align(std::min<u32>(_stacksz, 0x100000), 4096) : 0x4000;

	const vm::addr_t stack_base{vm::alloc(_stacksz, vm::stack, 4096)};

	if (!stack_base)
	{
		return CELL_ENOMEM;
	}

	const u32 tid = idm::import<named_thread<ppu_thread>>([&]()
	{
		const u32 tid = idm::last_id();

		std::string ppu_name;
		std::string full_name = fmt::format("PPU[0x%x] Thread", tid);

		if (threadname)
		{
			ppu_name = threadname.get_ptr();
			fmt::append(full_name, " (%s)", ppu_name);
		}

		ppu_thread_params p;
		p.stack_addr = stack_base;
		p.stack_size = stack_size;
		p.tls_addr = param->tls;
		p.entry = param->entry;
		p.arg0 = arg;
		p.arg1 = unk;

		return std::make_shared<named_thread<ppu_thread>>(full_name, p, ppu_name, prio, 1 - static_cast<int>(flags & 3));
	});

	if (!tid)
	{
		return CELL_EAGAIN;
	}

	*thread_id = tid;
	return CELL_OK;
}

error_code sys_ppu_thread_start(ppu_thread& ppu, u32 thread_id)
{
	sys_ppu_thread.trace("sys_ppu_thread_start(thread_id=0x%x)", thread_id);

	const auto thread = idm::get<named_thread<ppu_thread>>(thread_id, [&](ppu_thread& thread)
	{
		lv2_obj::awake(thread, -2);
	});

	if (!thread)
	{
		return CELL_ESRCH;
	}

	if (!thread->state.test_and_reset(cpu_flag::stop))
	{
		// TODO: what happens there?
		return CELL_EPERM;
	}
	else
	{
		thread_ctrl::notify(*thread);

		// Dirty hack for sound: confirm the creation of _mxr000 event queue
		if (thread->ppu_name.get() == "_cellsurMixerMain"sv)
		{
			lv2_obj::sleep(ppu);

			while (!idm::select<lv2_obj, lv2_event_queue>([](u32, lv2_event_queue& eq)
			{
				//some games do not set event queue name, though key seems constant for them
				return (eq.name == "_mxr000\0"_u64) || (eq.key == 0x8000cafe02460300);
			}))
			{
				if (ppu.is_stopped())
				{
					return 0;
				}

				thread_ctrl::wait_for(50000);
			}

			if (ppu.test_stopped())
			{
				return 0;
			}
		}
	}

	return CELL_OK;
}

error_code sys_ppu_thread_rename(u32 thread_id, vm::cptr<char> name)
{
	sys_ppu_thread.warning("sys_ppu_thread_rename(thread_id=0x%x, name=%s)", thread_id, name);

	const auto thread = idm::get<named_thread<ppu_thread>>(thread_id);

	if (!thread)
	{
		return CELL_ESRCH;
	}

	// thread_ctrl name is not changed (TODO)
	thread->ppu_name.assign(name.get_ptr());
	return CELL_OK;
}

error_code sys_ppu_thread_recover_page_fault(u32 thread_id)
{
	sys_ppu_thread.warning("sys_ppu_thread_recover_page_fault(thread_id=0x%x)", thread_id);

	const auto thread = idm::get<named_thread<ppu_thread>>(thread_id);

	if (!thread)
	{
		return CELL_ESRCH;
	}

	// We can only wake a thread if it is being suspended for a page fault.
	auto pf_events = fxm::get_always<page_fault_event_entries>();
	auto pf_event_ind = pf_events->events.begin();

	for (auto event_ind = pf_events->events.begin(); event_ind != pf_events->events.end(); ++event_ind)
	{
		if (event_ind->thread_id == thread_id)
		{
			pf_event_ind = event_ind;
			break;
		}
	}

	if (pf_event_ind == pf_events->events.end())
	{ // if not found...
		return CELL_EINVAL;
	}

	pf_events->events.erase(pf_event_ind);

	lv2_obj::awake(*thread);
	return CELL_OK;
}

error_code sys_ppu_thread_get_page_fault_context(u32 thread_id, vm::ptr<sys_ppu_thread_icontext_t> ctxt)
{
	sys_ppu_thread.todo("sys_ppu_thread_get_page_fault_context(thread_id=0x%x, ctxt=*0x%x)", thread_id, ctxt);

	const auto thread = idm::get<named_thread<ppu_thread>>(thread_id);

	if (!thread)
	{
		return CELL_ESRCH;
	}

	// We can only get a context if the thread is being suspended for a page fault.
	auto pf_events = fxm::get_always<page_fault_event_entries>();

	bool found = false;
	for (const auto& ev : pf_events->events)
	{
		if (ev.thread_id == thread_id)
		{
			found = true;
			break;
		}
	}
	if (!found)
	{
		return CELL_EINVAL;
	}

	// TODO: Fill ctxt with proper information.

	return CELL_OK;
}