#    Copyright 2018 ARM Limited
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
# pylint: disable=protected-access

import os
from copy import copy

from devlib import AndroidTarget, TargetError
from devlib.target import KernelConfig, KernelVersion, Cpuinfo
from devlib.utils.android import AndroidProperties

from wa.framework.configuration.core import settings
from wa.framework.exception import ConfigError
from wa.utils.serializer import read_pod, write_pod


def cpuinfo_from_pod(pod):
    cpuinfo = Cpuinfo('')
    cpuinfo.sections = pod['cpuinfo']
    lines = []
    for section in cpuinfo.sections:
        for key, value in section.items():
            line = '{}: {}'.format(key, value)
            lines.append(line)
        lines.append('')
    cpuinfo.text = '\n'.join(lines)
    return cpuinfo


def kernel_version_from_pod(pod):
    release_string = pod['kernel_release']
    version_string = pod['kernel_version']
    if release_string:
        if version_string:
            kernel_string = '{} #{}'.format(release_string, version_string)
        else:
            kernel_string = release_string
    else:
        kernel_string = '#{}'.format(version_string)
    return KernelVersion(kernel_string)


def kernel_config_from_pod(pod):
    config = KernelConfig('')
    config._config = pod['kernel_config']
    lines = []
    for key, value in config._config.items():
        if value == 'n':
            lines.append('# {} is not set'.format(key))
        else:
            lines.append('{}={}'.format(key, value))
    config.text = '\n'.join(lines)
    return config


class CpufreqInfo(object):

    @staticmethod
    def from_pod(pod):
        return CpufreqInfo(**pod)

    def __init__(self, **kwargs):
        self.available_frequencies = kwargs.pop('available_frequencies', [])
        self.available_governors = kwargs.pop('available_governors', [])
        self.related_cpus = kwargs.pop('related_cpus', [])
        self.driver = kwargs.pop('driver', None)

    def to_pod(self):
        return copy(self.__dict__)

    def __repr__(self):
        return 'Cpufreq({} {})'.format(self.driver, self.related_cpus)

    __str__ = __repr__


class IdleStateInfo(object):

    @staticmethod
    def from_pod(pod):
        return IdleStateInfo(**pod)

    def __init__(self, **kwargs):
        self.name = kwargs.pop('name', None)
        self.desc = kwargs.pop('desc', None)
        self.power = kwargs.pop('power', None)
        self.latency = kwargs.pop('latency', None)

    def to_pod(self):
        return copy(self.__dict__)

    def __repr__(self):
        return 'IdleState({}/{})'.format(self.name, self.desc)

    __str__ = __repr__


class CpuidleInfo(object):

    @staticmethod
    def from_pod(pod):
        instance = CpuidleInfo()
        instance.governor = pod['governor']
        instance.driver = pod['driver']
        instance.states = [IdleStateInfo.from_pod(s) for s in pod['states']]
        return instance

    @property
    def num_states(self):
        return len(self.states)

    def __init__(self):
        self.governor = None
        self.driver = None
        self.states = []

    def to_pod(self):
        pod = {}
        pod['governor'] = self.governor
        pod['driver'] = self.driver
        pod['states'] = [s.to_pod() for s in self.states]
        return pod

    def __repr__(self):
        return 'Cpuidle({}/{} {} states)'.format(
            self.governor, self.driver, self.num_states)

    __str__ = __repr__


class CpuInfo(object):

    @staticmethod
    def from_pod(pod):
        instance = CpuInfo()
        instance.id = pod['id']
        instance.name = pod['name']
        instance.architecture = pod['architecture']
        instance.features = pod['features']
        instance.cpufreq = CpufreqInfo.from_pod(pod['cpufreq'])
        instance.cpuidle = CpuidleInfo.from_pod(pod['cpuidle'])
        return instance

    def __init__(self):
        self.id = None
        self.name = None
        self.architecture = None
        self.features = []
        self.cpufreq = CpufreqInfo()
        self.cpuidle = CpuidleInfo()

    def to_pod(self):
        pod = {}
        pod['id'] = self.id
        pod['name'] = self.name
        pod['architecture'] = self.architecture
        pod['features'] = self.features
        pod['cpufreq'] = self.cpufreq.to_pod()
        pod['cpuidle'] = self.cpuidle.to_pod()
        return pod

    def __repr__(self):
        return 'Cpu({} {})'.format(self.id, self.name)

    __str__ = __repr__


def get_target_info(target):
    info = TargetInfo()
    info.target = target.__class__.__name__
    info.os = target.os
    info.os_version = target.os_version
    info.system_id = target.system_id
    info.abi = target.abi
    info.is_rooted = target.is_rooted
    info.kernel_version = target.kernel_version
    info.kernel_config = target.config
    try:
        info.sched_features = target.read_value('/sys/kernel/debug/sched_features').split()
    except TargetError:
        # best effort -- debugfs might not be mounted
        pass

    hostid_string = target.execute('{} hostid'.format(target.busybox)).strip()
    info.hostid = int(hostid_string, 16)
    info.hostname = target.execute('{} hostname'.format(target.busybox)).strip()

    for i, name in enumerate(target.cpuinfo.cpu_names):
        cpu = CpuInfo()
        cpu.id = i
        cpu.name = name
        cpu.features = target.cpuinfo.get_cpu_features(i)
        cpu.architecture = target.cpuinfo.architecture

        if target.has('cpufreq'):
            cpu.cpufreq.available_governors = target.cpufreq.list_governors(i)
            cpu.cpufreq.available_frequencies = target.cpufreq.list_frequencies(i)
            cpu.cpufreq.related_cpus = target.cpufreq.get_related_cpus(i)
            cpu.cpufreq.driver = target.cpufreq.get_driver(i)

        if target.has('cpuidle'):
            cpu.cpuidle.driver = target.cpuidle.get_driver()
            cpu.cpuidle.governor = target.cpuidle.get_governor()
            for state in target.cpuidle.get_states(i):
                state_info = IdleStateInfo()
                state_info.name = state.name
                state_info.desc = state.desc
                state_info.power = state.power
                state_info.latency = state.latency
                cpu.cpuidle.states.append(state_info)

        info.cpus.append(cpu)

    info.page_size_kb = target.page_size_kb

    if isinstance(target, AndroidTarget):
        info.screen_resolution = target.screen_resolution
        info.prop = target.getprop()
        info.android_id = target.android_id

    return info


def read_target_info_cache():
    if not os.path.exists(settings.cache_directory):
        os.makedirs(settings.cache_directory)
    if not os.path.isfile(settings.target_info_cache_file):
        return {}
    return read_pod(settings.target_info_cache_file)


def write_target_info_cache(cache):
    if not os.path.exists(settings.cache_directory):
        os.makedirs(settings.cache_directory)
    write_pod(cache, settings.target_info_cache_file)


def get_target_info_from_cache(system_id):
    cache = read_target_info_cache()
    pod = cache.get(system_id, None)

    if not pod:
        return None

    pod_version = pod.get('format_version', 0)
    if pod_version != TargetInfo.format_version:
        msg = 'Target info version mismatch. Expected {}, but found {}.\nTry deleting {}'
        raise ConfigError(msg.format(TargetInfo.format_version, pod_version,
                                     settings.target_info_cache_file))
    return TargetInfo.from_pod(pod)


def cache_target_info(target_info, overwrite=False):
    cache = read_target_info_cache()
    if target_info.system_id in cache and not overwrite:
        raise ValueError('TargetInfo for {} is already in cache.'.format(target_info.system_id))
    cache[target_info.system_id] = target_info.to_pod()
    write_target_info_cache(cache)


class TargetInfo(object):

    format_version = 2

    @staticmethod
    def from_pod(pod):
        instance = TargetInfo()
        instance.target = pod['target']
        instance.abi = pod['abi']
        instance.cpus = [CpuInfo.from_pod(c) for c in pod['cpus']]
        instance.os = pod['os']
        instance.os_version = pod['os_version']
        instance.system_id = pod['system_id']
        instance.hostid = pod['hostid']
        instance.hostname = pod['hostname']
        instance.abi = pod['abi']
        instance.is_rooted = pod['is_rooted']
        instance.kernel_version = kernel_version_from_pod(pod)
        instance.kernel_config = kernel_config_from_pod(pod)
        instance.sched_features = pod['sched_features']
        instance.page_size_kb = pod.get('page_size_kb')
        if instance.os == 'android':
            instance.screen_resolution = pod['screen_resolution']
            instance.prop = AndroidProperties('')
            instance.prop._properties = pod['prop']
            instance.android_id = pod['android_id']

        return instance

    def __init__(self):
        self.target = None
        self.cpus = []
        self.os = None
        self.os_version = None
        self.system_id = None
        self.hostid = None
        self.hostname = None
        self.abi = None
        self.is_rooted = None
        self.kernel_version = None
        self.kernel_config = None
        self.sched_features = None
        self.screen_resolution = None
        self.prop = None
        self.android_id = None
        self.page_size_kb = None

    def to_pod(self):
        pod = {}
        pod['format_version'] = self.format_version
        pod['target'] = self.target
        pod['abi'] = self.abi
        pod['cpus'] = [c.to_pod() for c in self.cpus]
        pod['os'] = self.os
        pod['os_version'] = self.os_version
        pod['system_id'] = self.system_id
        pod['hostid'] = self.hostid
        pod['hostname'] = self.hostname
        pod['abi'] = self.abi
        pod['is_rooted'] = self.is_rooted
        pod['kernel_release'] = self.kernel_version.release
        pod['kernel_version'] = self.kernel_version.version
        pod['kernel_config'] = dict(self.kernel_config.iteritems())
        pod['sched_features'] = self.sched_features
        pod['page_size_kb'] = self.page_size_kb
        if self.os == 'android':
            pod['screen_resolution'] = self.screen_resolution
            pod['prop'] = self.prop._properties
            pod['android_id'] = self.android_id

        return pod