from __future__ import print_function

from collections import OrderedDict
import importlib
import json
import logging
import re

from typing import List, Optional, Tuple, Set, Union, Any, Dict
import voluptuous as vol

from esphomeyaml import core, core_config, yaml_util
from esphomeyaml.components import substitutions
from esphomeyaml.const import CONF_ESPHOMEYAML, CONF_PLATFORM, ESP_PLATFORMS
from esphomeyaml.core import CORE, EsphomeyamlError, ConfigType
from esphomeyaml.helpers import color, indent
from esphomeyaml.util import safe_print

_LOGGER = logging.getLogger(__name__)

_COMPONENT_CACHE = {}


def get_component(domain):
    if domain in _COMPONENT_CACHE:
        return _COMPONENT_CACHE[domain]

    path = 'esphomeyaml.components.{}'.format(domain)
    try:
        module = importlib.import_module(path)
    except (ImportError, ValueError) as err:
        _LOGGER.debug(err)
    else:
        _COMPONENT_CACHE[domain] = module
        return module

    _LOGGER.error("Unable to find component %s", domain)
    return None


def get_platform(domain, platform):
    return get_component("{}.{}".format(domain, platform))


def is_platform_component(component):
    return hasattr(component, 'PLATFORM_SCHEMA')


def iter_components(config):
    for domain, conf in config.iteritems():
        if domain == CONF_ESPHOMEYAML:
            yield CONF_ESPHOMEYAML, core_config, conf
            continue
        component = get_component(domain)
        yield domain, component, conf
        if is_platform_component(component):
            for p_config in conf:
                p_name = u"{}.{}".format(domain, p_config[CONF_PLATFORM])
                platform = get_component(p_name)
                yield p_name, platform, p_config


ConfigPath = List[Union[basestring, int]]


def _path_begins_with_(path, other):  # type: (ConfigPath, ConfigPath) -> bool
    if len(path) < len(other):
        return False
    return path[:len(other)] == other


def _path_begins_with(path, other):  # type: (ConfigPath, ConfigPath) -> bool
    ret = _path_begins_with_(path, other)
    # print('_path_begins_with({}, {}) -> {}'.format(path, other, ret))
    return ret


class Config(OrderedDict):
    def __init__(self):
        super(Config, self).__init__()
        self.errors = []  # type: List[Tuple[basestring, ConfigPath]]
        self.domains = []  # type: List[Tuple[ConfigPath, basestring]]

    def add_error(self, message, path):
        # type: (basestring, ConfigPath) -> None
        if not isinstance(message, unicode):
            message = unicode(message)
        self.errors.append((message, path))

    def add_domain(self, path, name):
        # type: (ConfigPath, basestring) -> None
        self.domains.append((path, name))

    def lookup_domain(self, path):
        # type: (ConfigPath) -> Optional[basestring]
        best_len = 0
        best_domain = None
        for d_path, domain in self.domains:
            if len(d_path) < best_len:
                continue
            if _path_begins_with(path, d_path):
                best_len = len(d_path)
                best_domain = domain
        return best_domain

    def is_in_error_path(self, path):
        for _, p in self.errors:
            if _path_begins_with(p, path):
                return True
        return False

    def get_error_for_path(self, path):
        for msg, p in self.errors:
            if p == path:
                return msg
        return None

    def nested_item(self, path):
        data = self
        for item_index in path:
            try:
                data = data[item_index]
            except (KeyError, IndexError, TypeError):
                return {}
        return data


def iter_ids(config, path=None):
    path = path or []
    if isinstance(config, core.ID):
        yield config, path
    elif isinstance(config, core.Lambda):
        for id in config.requires_ids:
            yield id, path
    elif isinstance(config, list):
        for i, item in enumerate(config):
            for result in iter_ids(item, path + [i]):
                yield result
    elif isinstance(config, dict):
        for key, value in config.iteritems():
            for result in iter_ids(value, path + [key]):
                yield result


def do_id_pass(result):  # type: (Config) -> None
    from esphomeyaml.cpp_generator import MockObjClass

    declare_ids = []  # type: List[Tuple[core.ID, ConfigPath]]
    searching_ids = []  # type: List[Tuple[core.ID, ConfigPath]]
    for id, path in iter_ids(result):
        if id.is_declaration:
            if id.id is not None and any(v[0].id == id.id for v in declare_ids):
                result.add_error(u"ID {} redefined!".format(id.id), path)
                continue
            declare_ids.append((id, path))
        else:
            searching_ids.append((id, path))
    # Resolve default ids after manual IDs
    for id, _ in declare_ids:
        id.resolve([v[0].id for v in declare_ids])

    # Check searched IDs
    for id, path in searching_ids:
        if id.id is not None:
            # manually declared
            match = next((v[0] for v in declare_ids if v[0].id == id.id), None)
            if match is None:
                # No declared ID with this name
                result.add_error("Couldn't find ID {}".format(id.id), path)
                continue
            if not isinstance(match.type, MockObjClass) or not isinstance(id.type, MockObjClass):
                continue
            if not match.type.inherits_from(id.type):
                result.add_error("ID '{}' of type {} doesn't inherit from {}. Please double check "
                                 "your ID is pointing to the correct value"
                                 "".format(id.id, match.type, id.type), path)

        if id.id is None and id.type is not None:
            for v in declare_ids:
                if v[0] is None or not isinstance(v[0].type, MockObjClass):
                    continue
                inherits = v[0].type.inherits_from(id.type)
                if inherits:
                    id.id = v[0].id
                    break
            else:
                result.add_error("Couldn't resolve ID for type {}".format(id.type), path)


def validate_config(config):
    result = Config()

    def _comp_error(ex, path):
        # type: (vol.Invalid, List[basestring]) -> None
        if isinstance(ex, vol.MultipleInvalid):
            errors = ex.errors
        else:
            errors = [ex]

        for e in errors:
            path_ = path + e.path
            domain = result.lookup_domain(path_) or ''
            result.add_error(_format_vol_invalid(e, config, path, domain), path_)

    skip_paths = list()  # type: List[ConfigPath]

    # Step 1: Load everything
    result.add_domain([CONF_ESPHOMEYAML], CONF_ESPHOMEYAML)

    for domain, conf in config.iteritems():
        domain = str(domain)
        if domain == CONF_ESPHOMEYAML or domain.startswith(u'.'):
            skip_paths.append([domain])
            continue
        result.add_domain([domain], domain)
        result[domain] = conf
        if conf is None:
            config[domain] = conf = {}
        component = get_component(domain)
        if component is None:
            result.add_error(u"Component not found: {}".format(domain), [domain])
            skip_paths.append([domain])
            continue

        success = True
        dependencies = getattr(component, 'DEPENDENCIES', [])
        for dependency in dependencies:
            if dependency not in config:
                result.add_error(u"Component {} requires component {}".format(domain, dependency), [domain])
                success = False
        if not success:
            skip_paths.append([domain])
            continue

        success = True
        conflicts_with = getattr(component, 'CONFLICTS_WITH', [])
        for conflict in conflicts_with:
            if conflict not in config:
                result.add_error(u"Component {} cannot be used together with component {}"
                                 u"".format(domain, conflict), [domain])
                success = False
        if not success:
            skip_paths.append([domain])
            continue

        esp_platforms = getattr(component, 'ESP_PLATFORMS', ESP_PLATFORMS)
        if CORE.esp_platform not in esp_platforms:
            result.add_error(u"Component {} doesn't support {}.".format(domain, CORE.esp_platform), [domain])
            skip_paths.append([domain])
            continue

        if not hasattr(component, 'PLATFORM_SCHEMA'):
            continue

        if not isinstance(conf, list) and conf:
            result[domain] = conf = [conf]

        for i, p_config in enumerate(conf):
            if not isinstance(p_config, dict):
                result.add_error(u"Platform schemas must have 'platform:' key", [domain, i])
                skip_paths.append([domain, i])
                continue
            p_name = p_config.get('platform')
            if p_name is None:
                result.add_error(u"No platform specified for {}".format(domain), [domain, i])
                skip_paths.append([domain, i])
                continue
            p_domain = u'{}.{}'.format(domain, p_name)
            result.add_domain([domain, i], p_domain)
            platform = get_platform(domain, p_name)
            if platform is None:
                result.add_error(u"Platform not found: '{}'".format(p_domain), [domain, i])
                skip_paths.append([domain, i])
                continue

            success = True
            dependencies = getattr(platform, 'DEPENDENCIES', [])
            for dependency in dependencies:
                if dependency not in config:
                    result.add_error(u"Platform {} requires component {}".format(p_domain, dependency),
                                     [domain, i])
                    success = False
            if not success:
                skip_paths.append([domain, i])
                continue

            success = True
            conflicts_with = getattr(platform, 'CONFLICTS_WITH', [])
            for conflict in conflicts_with:
                if conflict not in config:
                    result.add_error(u"Platform {} cannot be used together with component {}"
                                     u"".format(p_domain, conflict), [domain, i])
                    success = False
            if not success:
                skip_paths.append([domain, i])
                continue

            esp_platforms = getattr(platform, 'ESP_PLATFORMS', ESP_PLATFORMS)
            if CORE.esp_platform not in esp_platforms:
                result.add_error(u"Platform {} doesn't support {}.".format(p_domain, CORE.esp_platform),
                                 [domain, i])
                skip_paths.append([domain, i])
                continue

    # Step 2: Validate configuration
    try:
        result[CONF_ESPHOMEYAML] = config[CONF_ESPHOMEYAML]
        result[CONF_ESPHOMEYAML] = core_config.CONFIG_SCHEMA(config[CONF_ESPHOMEYAML])
    except vol.Invalid as ex:
        _comp_error(ex, [CONF_ESPHOMEYAML])

    for domain, conf in config.iteritems():
        domain = str(domain)
        if [domain] in skip_paths:
            continue
        component = get_component(domain)

        if hasattr(component, 'CONFIG_SCHEMA'):
            try:
                validated = component.CONFIG_SCHEMA(conf)
                result[domain] = validated
            except vol.Invalid as ex:
                _comp_error(ex, [domain])
                continue

        if not hasattr(component, 'PLATFORM_SCHEMA'):
            continue

        for i, p_config in enumerate(conf):
            if [domain, i] in skip_paths:
                continue
            p_name = p_config['platform']
            platform = get_platform(domain, p_name)

            if hasattr(platform, 'PLATFORM_SCHEMA'):
                try:
                    p_validated = platform.PLATFORM_SCHEMA(p_config)
                except vol.Invalid as ex:
                    _comp_error(ex, [domain, i])
                    continue
                result[domain][i] = p_validated

    do_id_pass(result)
    return result


def _nested_getitem(data, path):
    for item_index in path:
        try:
            data = data[item_index]
        except (KeyError, IndexError, TypeError):
            return None
    return data


def humanize_error(config, validation_error):
    offending_item_summary = _nested_getitem(config, validation_error.path)
    if isinstance(offending_item_summary, dict):
        try:
            offending_item_summary = json.dumps(offending_item_summary)
        except (TypeError, ValueError):
            pass
    validation_error = unicode(validation_error)
    m = re.match(r'^(.*)\s*for dictionary value @.*$', validation_error)
    if m is not None:
        validation_error = m.group(1)
    validation_error = validation_error.strip()
    if not validation_error.endswith(u'.'):
        validation_error += u'.'
    return u"{} Got '{}'".format(validation_error, offending_item_summary)


def _format_vol_invalid(ex, config, path, domain):
    # type: (vol.Invalid, ConfigType, ConfigPath, basestring) -> unicode
    message = u''
    if u'extra keys not allowed' in ex.error_message:
        message += u'[{}] is an invalid option for [{}].'.format(ex.path[-1], domain)
    elif u'required key not provided' in ex.error_message:
        message += u"'{}' is a required option for [{}].".format(ex.path[-1], domain)
    else:
        message += u'{}.'.format(humanize_error(_nested_getitem(config, path), ex))

    return message


def load_config():
    try:
        config = yaml_util.load_yaml(CORE.config_path)
    except OSError:
        raise EsphomeyamlError(u"Could not read configuration file at {}".format(CORE.config_path))
    CORE.raw_config = config
    config = substitutions.do_substitution_pass(config)
    core_config.preload_core_config(config)

    try:
        result = validate_config(config)
    except EsphomeyamlError:
        raise
    except Exception:
        _LOGGER.error(u"Unexpected exception while reading configuration:")
        raise

    return result


def line_info(obj):
    """Display line config source."""
    if hasattr(obj, '__config_file__'):
        return color('cyan', "[source {}:{}]"
                     .format(obj.__config_file__, obj.__line__ or '?'))
    return None


def _print_on_next_line(obj):
    if isinstance(obj, (list, tuple, dict)):
        return True
    if isinstance(obj, str):
        return len(obj) > 80
    if isinstance(obj, core.Lambda):
        return len(obj.value) > 80
    return False


def dump_dict(config, path, at_root=True):
    # type: (Config, ConfigPath, bool) -> Tuple[unicode, bool]
    conf = config.nested_item(path)
    ret = u''
    multiline = False

    if at_root:
        error = config.get_error_for_path(path)
        if error is not None:
            ret += u'\n' + color('bold_red', error) + u'\n'

    if isinstance(conf, (list, tuple)):
        multiline = True
        for i, obj in enumerate(conf):
            path_ = path + [i]
            error = config.get_error_for_path(path_)
            if error is not None:
                ret += u'\n' + color('bold_red', error) + u'\n'

            sep = u'- '
            if config.is_in_error_path(path_):
                sep = color('red', sep)
            msg, _ = dump_dict(config, path_, at_root=False)
            msg = indent(msg)
            inf = line_info(config.nested_item(path_))
            if inf is not None:
                msg = inf + u'\n' + msg
            elif msg:
                msg = msg[2:]
            ret += sep + msg + u'\n'
    elif isinstance(conf, dict):
        multiline = True
        for k, v in conf.iteritems():
            path_ = path + [k]
            error = config.get_error_for_path(path_)
            if error is not None:
                ret += u'\n' + color('bold_red', error) + u'\n'

            st = u'{}: '.format(k)
            if config.is_in_error_path(path_):
                st = color('red', st)
            msg, m = dump_dict(config, path_, at_root=False)

            inf = line_info(config.nested_item(path_))
            if m:
                msg = u'\n' + indent(msg)

            if inf is not None:
                if m:
                    msg = u' ' + inf + msg
                else:
                    msg = msg + u' ' + inf
            ret += st + msg + u'\n'
    elif isinstance(conf, str):
        if len(conf) > 80:
            ret += u'|-\n'
            conf = indent(conf)
        error = config.get_error_for_path(path)
        col = 'bold_red' if error else 'white'
        ret += color(col, unicode(conf))
    elif isinstance(conf, core.Lambda):
        ret += u'|-\n'
        conf = indent(unicode(conf.value))
        error = config.get_error_for_path(path)
        col = 'bold_red' if error else 'white'
        ret += color(col, conf)
    else:
        error = config.get_error_for_path(path)
        col = 'bold_red' if error else 'white'
        ret += color(col, unicode(conf))
        multiline = u'\n' in ret

    return ret, multiline


def read_config():
    _LOGGER.info("Reading configuration...")
    try:
        res = load_config()
    except EsphomeyamlError as err:
        _LOGGER.error(u"Error while reading config: %s", err)
        return None
    if res.errors:
        safe_print(color('bold_red', u"Failed config"))
        safe_print('')
        for path, domain in res.domains:
            if not res.is_in_error_path(path):
                continue

            safe_print(color('bold_red', u'{}:'.format(domain)) + u' ' + (line_info(res.nested_item(path)) or u''))
            safe_print(indent(dump_dict(res, path)[0]))
        return None
    return OrderedDict(res)