# Copyright 2015, 2016 OpenMarket Ltd
#
# 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.

from synapse.push.rulekinds import PRIORITY_CLASS_MAP, PRIORITY_CLASS_INVERSE_MAP
import copy


def list_with_base_rules(rawrules):
    """Combine the list of rules set by the user with the default push rules

    Args:
        rawrules(list): The rules the user has modified or set.

    Returns:
        A new list with the rules set by the user combined with the defaults.
    """
    ruleslist = []

    # Grab the base rules that the user has modified.
    # The modified base rules have a priority_class of -1.
    modified_base_rules = {
        r['rule_id']: r for r in rawrules if r['priority_class'] < 0
    }

    # Remove the modified base rules from the list, They'll be added back
    # in the default postions in the list.
    rawrules = [r for r in rawrules if r['priority_class'] >= 0]

    # shove the server default rules for each kind onto the end of each
    current_prio_class = PRIORITY_CLASS_INVERSE_MAP.keys()[-1]

    ruleslist.extend(make_base_prepend_rules(
        PRIORITY_CLASS_INVERSE_MAP[current_prio_class], modified_base_rules
    ))

    for r in rawrules:
        if r['priority_class'] < current_prio_class:
            while r['priority_class'] < current_prio_class:
                ruleslist.extend(make_base_append_rules(
                    PRIORITY_CLASS_INVERSE_MAP[current_prio_class],
                    modified_base_rules,
                ))
                current_prio_class -= 1
                if current_prio_class > 0:
                    ruleslist.extend(make_base_prepend_rules(
                        PRIORITY_CLASS_INVERSE_MAP[current_prio_class],
                        modified_base_rules,
                    ))

        ruleslist.append(r)

    while current_prio_class > 0:
        ruleslist.extend(make_base_append_rules(
            PRIORITY_CLASS_INVERSE_MAP[current_prio_class],
            modified_base_rules,
        ))
        current_prio_class -= 1
        if current_prio_class > 0:
            ruleslist.extend(make_base_prepend_rules(
                PRIORITY_CLASS_INVERSE_MAP[current_prio_class],
                modified_base_rules,
            ))

    return ruleslist


def make_base_append_rules(kind, modified_base_rules):
    rules = []

    if kind == 'override':
        rules = BASE_APPEND_OVERRIDE_RULES
    elif kind == 'underride':
        rules = BASE_APPEND_UNDERRIDE_RULES
    elif kind == 'content':
        rules = BASE_APPEND_CONTENT_RULES

    # Copy the rules before modifying them
    rules = copy.deepcopy(rules)
    for r in rules:
        # Only modify the actions, keep the conditions the same.
        modified = modified_base_rules.get(r['rule_id'])
        if modified:
            r['actions'] = modified['actions']

    return rules


def make_base_prepend_rules(kind, modified_base_rules):
    rules = []

    if kind == 'override':
        rules = BASE_PREPEND_OVERRIDE_RULES

    # Copy the rules before modifying them
    rules = copy.deepcopy(rules)
    for r in rules:
        # Only modify the actions, keep the conditions the same.
        modified = modified_base_rules.get(r['rule_id'])
        if modified:
            r['actions'] = modified['actions']

    return rules


BASE_APPEND_CONTENT_RULES = [
    {
        'rule_id': 'global/content/.m.rule.contains_user_name',
        'conditions': [
            {
                'kind': 'event_match',
                'key': 'content.body',
                'pattern_type': 'user_localpart'
            }
        ],
        'actions': [
            'notify',
            {
                'set_tweak': 'sound',
                'value': 'default',
            }, {
                'set_tweak': 'highlight'
            }
        ]
    },
]


BASE_PREPEND_OVERRIDE_RULES = [
    {
        'rule_id': 'global/override/.m.rule.master',
        'enabled': False,
        'conditions': [],
        'actions': [
            "dont_notify"
        ]
    }
]


BASE_APPEND_OVERRIDE_RULES = [
    {
        'rule_id': 'global/override/.m.rule.suppress_notices',
        'conditions': [
            {
                'kind': 'event_match',
                'key': 'content.msgtype',
                'pattern': 'm.notice',
                '_id': '_suppress_notices',
            }
        ],
        'actions': [
            'dont_notify',
        ]
    },
    # NB. .m.rule.invite_for_me must be higher prio than .m.rule.member_event
    # otherwise invites will be matched by .m.rule.member_event
    {
        'rule_id': 'global/override/.m.rule.invite_for_me',
        'conditions': [
            {
                'kind': 'event_match',
                'key': 'type',
                'pattern': 'm.room.member',
                '_id': '_member',
            },
            {
                'kind': 'event_match',
                'key': 'content.membership',
                'pattern': 'invite',
                '_id': '_invite_member',
            },
            {
                'kind': 'event_match',
                'key': 'state_key',
                'pattern_type': 'user_id'
            },
        ],
        'actions': [
            'notify',
            {
                'set_tweak': 'sound',
                'value': 'default'
            }, {
                'set_tweak': 'highlight',
                'value': False
            }
        ]
    },
    # Will we sometimes want to know about people joining and leaving?
    # Perhaps: if so, this could be expanded upon. Seems the most usual case
    # is that we don't though. We add this override rule so that even if
    # the room rule is set to notify, we don't get notifications about
    # join/leave/avatar/displayname events.
    # See also: https://matrix.org/jira/browse/SYN-607
    {
        'rule_id': 'global/override/.m.rule.member_event',
        'conditions': [
            {
                'kind': 'event_match',
                'key': 'type',
                'pattern': 'm.room.member',
                '_id': '_member',
            }
        ],
        'actions': [
            'dont_notify'
        ]
    },
    # This was changed from underride to override so it's closer in priority
    # to the content rules where the user name highlight rule lives. This
    # way a room rule is lower priority than both but a custom override rule
    # is higher priority than both.
    {
        'rule_id': 'global/override/.m.rule.contains_display_name',
        'conditions': [
            {
                'kind': 'contains_display_name'
            }
        ],
        'actions': [
            'notify',
            {
                'set_tweak': 'sound',
                'value': 'default'
            }, {
                'set_tweak': 'highlight'
            }
        ]
    },
]


BASE_APPEND_UNDERRIDE_RULES = [
    {
        'rule_id': 'global/underride/.m.rule.call',
        'conditions': [
            {
                'kind': 'event_match',
                'key': 'type',
                'pattern': 'm.call.invite',
                '_id': '_call',
            }
        ],
        'actions': [
            'notify',
            {
                'set_tweak': 'sound',
                'value': 'ring'
            }, {
                'set_tweak': 'highlight',
                'value': False
            }
        ]
    },
    # XXX: once m.direct is standardised everywhere, we should use it to detect
    # a DM from the user's perspective rather than this heuristic.
    {
        'rule_id': 'global/underride/.m.rule.room_one_to_one',
        'conditions': [
            {
                'kind': 'room_member_count',
                'is': '2',
                '_id': 'member_count',
            },
            {
                'kind': 'event_match',
                'key': 'type',
                'pattern': 'm.room.message',
                '_id': '_message',
            }
        ],
        'actions': [
            'notify',
            {
                'set_tweak': 'sound',
                'value': 'default'
            }, {
                'set_tweak': 'highlight',
                'value': False
            }
        ]
    },
    # XXX: this is going to fire for events which aren't m.room.messages
    # but are encrypted (e.g. m.call.*)...
    {
        'rule_id': 'global/underride/.m.rule.encrypted_room_one_to_one',
        'conditions': [
            {
                'kind': 'room_member_count',
                'is': '2',
                '_id': 'member_count',
            },
            {
                'kind': 'event_match',
                'key': 'type',
                'pattern': 'm.room.encrypted',
                '_id': '_encrypted',
            }
        ],
        'actions': [
            'notify',
            {
                'set_tweak': 'sound',
                'value': 'default'
            }, {
                'set_tweak': 'highlight',
                'value': False
            }
        ]
    },
    {
        'rule_id': 'global/underride/.m.rule.message',
        'conditions': [
            {
                'kind': 'event_match',
                'key': 'type',
                'pattern': 'm.room.message',
                '_id': '_message',
            }
        ],
        'actions': [
            'notify', {
                'set_tweak': 'highlight',
                'value': False
            }
        ]
    },
    # XXX: this is going to fire for events which aren't m.room.messages
    # but are encrypted (e.g. m.call.*)...
    {
        'rule_id': 'global/underride/.m.rule.encrypted',
        'conditions': [
            {
                'kind': 'event_match',
                'key': 'type',
                'pattern': 'm.room.encrypted',
                '_id': '_encrypted',
            }
        ],
        'actions': [
            'notify', {
                'set_tweak': 'highlight',
                'value': False
            }
        ]
    }
]


BASE_RULE_IDS = set()

for r in BASE_APPEND_CONTENT_RULES:
    r['priority_class'] = PRIORITY_CLASS_MAP['content']
    r['default'] = True
    BASE_RULE_IDS.add(r['rule_id'])

for r in BASE_PREPEND_OVERRIDE_RULES:
    r['priority_class'] = PRIORITY_CLASS_MAP['override']
    r['default'] = True
    BASE_RULE_IDS.add(r['rule_id'])

for r in BASE_APPEND_OVERRIDE_RULES:
    r['priority_class'] = PRIORITY_CLASS_MAP['override']
    r['default'] = True
    BASE_RULE_IDS.add(r['rule_id'])

for r in BASE_APPEND_UNDERRIDE_RULES:
    r['priority_class'] = PRIORITY_CLASS_MAP['underride']
    r['default'] = True
    BASE_RULE_IDS.add(r['rule_id'])
