# Copyright 2024 Max Planck Institute for Software Systems, and
# National University of Singapore
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
# CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

from __future__ import annotations

import math
import asyncio
import simbricks.orchestration.simulation.base as sim_base
import simbricks.orchestration.system as system
from simbricks.orchestration.instantiation import base as inst_base
from simbricks.orchestration.system import host as sys_host
from simbricks.orchestration.system import pcie as sys_pcie
from simbricks.orchestration.system import mem as sys_mem
from simbricks.orchestration.utils import base as utils_base


class HostSim(sim_base.Simulator):

    def __init__(self, simulation: sim_base.Simulation, executable: str, name=""):
        super().__init__(simulation=simulation, executable=executable, name=name)

    def full_name(self) -> str:
        return "host." + self.name

    def add(self, host: sys_host.Host):
        super().add(host)

    def config_str(self) -> str:
        return []

    def supported_image_formats(self) -> list[str]:
        raise Exception("implement me")

    def supported_socket_types(
        self, interface: system.Interface
    ) -> set[inst_base.SockType]:
        return [inst_base.SockType.CONNECT]


class Gem5Sim(HostSim):

    def __init__(self, simulation: sim_base.Simulation):
        super().__init__(
            simulation=simulation, executable="sims/external/gem5/build/X86/gem5"
        )
        self.name = f"Gem5Sim-{self._id}"
        self.cpu_type_cp = "X86KvmCPU"
        self.cpu_type = "TimingSimpleCPU"
        self.extra_main_args: list[str] = []
        self.extra_config_args: list[str] = []
        self._variant: str = "fast"
        self._sys_clock: str = "1GHz"  # TODO: move to system module

    def supports_checkpointing(self) -> bool:
        return True

    def resreq_cores(self) -> int:
        return 1

    def resreq_mem(self) -> int:
        return 4096

    def supported_image_formats(self) -> list[str]:
        return ["raw"]

    async def prepare(self, inst: inst_base.Instantiation) -> None:
        await super().prepare(inst=inst)

        prep_cmds = [f"mkdir -p {inst.cpdir_subdir(sim=self)}"]
        task = asyncio.create_task(
            inst.executor.run_cmdlist(label="prepare", cmds=prep_cmds, verbose=True)
        )
        await task

    def checkpoint_commands(self) -> list[str]:
        return ["m5 checkpoint"]

    def cleanup_commands(self) -> list[str]:
        return ["m5 exit"]

    def run_cmd(self, inst: inst_base.Instantiation) -> str:
        cpu_type = self.cpu_type
        if inst.create_checkpoint:
            cpu_type = self.cpu_type_cp

        full_sys_hosts = self.filter_components_by_type(ty=sys_host.BaseLinuxHost)
        if len(full_sys_hosts) != 1:
            raise Exception("Gem5Sim only supports simulating 1 FullSystemHost")
        host_spec = full_sys_hosts[0]

        cmd = f"{inst.join_repo_base(f'{self._executable}.{self._variant}')} --outdir={inst.get_simmulator_output_dir(sim=self)} "
        cmd += " ".join(self.extra_main_args)
        cmd += (
            f" {inst.join_repo_base('sims/external/gem5/configs/simbricks/simbricks.py')} --caches --l2cache "
            "--l1d_size=32kB --l1i_size=32kB --l2_size=32MB "
            "--l1d_assoc=8 --l1i_assoc=8 --l2_assoc=16 "
            f"--cacheline_size=64 --cpu-clock={host_spec.cpu_freq}"
            f" --sys-clock={self._sys_clock} "
            f"--checkpoint-dir={inst.cpdir_subdir(sim=self)} "
            f"--kernel={inst.join_repo_base('images/vmlinux')} "
        )
        for disk in host_spec.disks:
            cmd += f"--disk-image={disk.path(inst=inst, format='raw')} "
        cmd += (
            f"--cpu-type={cpu_type} --mem-size={host_spec.memory}MB "
            f"--num-cpus={host_spec.cores} "
            "--mem-type=DDR4_2400_16x4 "
        )

        if host_spec.kcmd_append is not None:
            cmd += f'--command-line-append="{host_spec.kcmd_append}" '

        if inst.create_checkpoint:
            cmd += "--max-checkpoints=1 "

        if inst.restore_checkpoint:
            cmd += "-r 1 "

        latency, sync_period, run_sync = (
            sim_base.Simulator.get_unique_latency_period_sync(
                channels=self.get_channels()
            )
        )

        fsh_interfaces = host_spec.interfaces()

        pci_interfaces = system.Interface.filter_by_type(
            interfaces=fsh_interfaces, ty=sys_pcie.PCIeHostInterface
        )
        for inf in pci_interfaces:
            socket = inst.get_socket(interface=inf)
            if socket is None:
                continue
            assert socket._type == inst_base.SockType.CONNECT
            cmd += (
                f"--simbricks-pci=connect:{socket._path}"
                f":latency={latency}ns"
                f":sync_interval={sync_period}ns"
            )
            if run_sync and not inst.create_checkpoint:
                cmd += ":sync"
            cmd += " "

        mem_interfaces = system.Interface.filter_by_type(
            interfaces=fsh_interfaces, ty=sys_mem.MemHostInterface
        )
        for inf in mem_interfaces:
            socket = inst.get_socket(interface=inf)
            if socket is None:
                continue
            assert socket._type == inst_base.SockType.CONNECT
            utils_base.has_expected_type(inf.component, sys_mem.MemSimpleDevice)
            dev: sys_mem.MemSimpleDevice = inf.component
            cmd += (
                f"--simbricks-mem={dev._size}@{dev._addr}@{dev._as_id}@"
                f"connect:{socket._path}"
                f":latency={latency}ns"
                f":sync_interval={sync_period}ns"
            )
            if run_sync and not inst.create_checkpoint:
                cmd += ":sync"
            cmd += " "

        # TODO: FIXME
        # for net in self.net_directs:
        #     cmd += (
        #         '--simbricks-eth-e1000=listen'
        #         f':{env.net2host_eth_path(net, self)}'
        #         f':{env.net2host_shm_path(net, self)}'
        #         f':latency={net.eth_latency}ns'
        #         f':sync_interval={net.sync_period}ns'
        #     )
        #     if cpu_type == 'TimingSimpleCPU':
        #         cmd += ':sync'
        #     cmd += ' '

        cmd += " ".join(self.extra_config_args)

        return cmd


class QemuSim(HostSim):

    def __init__(self, simulation: sim_base.Simulation) -> None:
        super().__init__(
            simulation=simulation,
            executable="sims/external/qemu/build/x86_64-softmmu/qemu-system-x86_64",
        )
        self.name = f"QemuSim-{self._id}"
        self._disks: list[tuple[str, str]] = []  # [(path, format)]

    def resreq_cores(self) -> int:
        return 1

    def resreq_mem(self) -> int:
        return 8192

    def supported_image_formats(self) -> list[str]:
        return ["raw", "qcow"]

    async def prepare(self, inst: inst_base.Instantiation) -> None:
        await super().prepare(inst=inst)

        full_sys_hosts = self.filter_components_by_type(ty=sys_host.FullSystemHost)
        if len(full_sys_hosts) != 1:
            raise Exception("QEMU only supports simulating 1 FullSystemHost")

        d = []
        for disk in full_sys_hosts[0].disks:
            format = (
                "qcow2"
                if not isinstance(disk, sys_host.LinuxConfigDiskImage)
                else "raw"
            )
            copy_path = await disk.make_qcow_copy(
                inst=inst,
                format=format,
            )
            assert copy_path is not None
            d.append((copy_path, format))
        self._disks = d

    def checkpoint_commands(self) -> list[str]:
        return []

    def cleanup_commands(self) -> list[str]:
        return ["poweroff -f"]

    def run_cmd(self, inst: inst_base.Instantiation) -> str:

        latency, period, sync = sim_base.Simulator.get_unique_latency_period_sync(
            channels=self.get_channels()
        )
        accel = ",accel=kvm:tcg" if not sync else ""

        cmd = (
            f"{inst.join_repo_base(relative_path=self._executable)} -machine q35{accel} -serial mon:stdio "
            "-cpu Skylake-Server -display none -nic none "
            f"-kernel {inst.join_repo_base('images/bzImage')} "
        )

        full_sys_hosts = self.filter_components_by_type(ty=sys_host.BaseLinuxHost)
        if len(full_sys_hosts) != 1:
            raise Exception("QEMU only supports simulating 1 FullSystemHost")
        host_spec = full_sys_hosts[0]

        kcmd_append = ""
        if host_spec.kcmd_append is not None:
            kcmd_append = " " + host_spec.kcmd_append

        for index, disk in enumerate(self._disks):
            cmd += f"-drive file={disk[0]},if=ide,index={index},media=disk,driver={disk[1]} "
        cmd += (
            '-append "earlyprintk=ttyS0 console=ttyS0 root=/dev/sda1 '
            f'init=/home/ubuntu/guestinit.sh rw{kcmd_append}" '
            f"-m {host_spec.memory} -smp {host_spec.cores} "
        )

        if sync:
            unit = host_spec.cpu_freq[-3:]
            if unit.lower() == "ghz":
                base = 0
            elif unit.lower() == "mhz":
                base = 3
            else:
                raise ValueError("cpu frequency specified in unsupported unit")
            num = float(host_spec.cpu_freq[:-3])
            shift = base - int(math.ceil(math.log(num, 2)))

            cmd += f" -icount shift={shift},sleep=off "

        fsh_interfaces = host_spec.interfaces()
        pci_interfaces = system.Interface.filter_by_type(
            interfaces=fsh_interfaces, ty=sys_pcie.PCIeHostInterface
        )
        for inf in pci_interfaces:
            socket = inst.get_socket(interface=inf)
            if socket is None:
                continue
            assert socket._type is inst_base.SockType.CONNECT
            cmd += f"-device simbricks-pci,socket={socket._path}"
            if sync:
                cmd += ",sync=on"
                cmd += f",pci-latency={latency}"
                cmd += f",sync-period={period}"
            else:
                cmd += ",sync=off"
            cmd += " "

        return cmd
