from datetime import datetime, timedelta
from uuid import UUID

from flask_marshmallow.fields import fields
from marshmallow import (
    EXCLUDE,
    ValidationError,
    post_dump,
    post_load,
    pre_dump,
    pre_load,
    validates,
    validates_schema,
)
from marshmallow_sqlalchemy import field_for
from notifications_utils.recipients import (
    InvalidEmailError,
    InvalidPhoneError,
    validate_and_format_phone_number,
    validate_email_address,
    validate_phone_number,
)

from app import ma, models
from app.dao.permissions_dao import permission_dao
from app.models import ServicePermission
from app.utils import DATETIME_FORMAT_NO_TIMEZONE, get_template_instance


def _validate_positive_number(value, msg="Not a positive integer"):
    try:
        page_int = int(value)
    except ValueError:
        raise ValidationError(msg)
    if page_int < 1:
        raise ValidationError(msg)


def _validate_datetime_not_more_than_96_hours_in_future(dte, msg="Date cannot be more than 96hrs in the future"):
    if dte > datetime.utcnow() + timedelta(hours=96):
        raise ValidationError(msg)


def _validate_datetime_not_in_past(dte, msg="Date cannot be in the past"):
    if dte < datetime.utcnow():
        raise ValidationError(msg)


class UUIDsAsStringsMixin:
    @post_dump()
    def __post_dump(self, data, **kwargs):
        for key, value in data.items():

            if isinstance(value, UUID):
                data[key] = str(value)

            if isinstance(value, list):
                data[key] = [
                    (str(item) if isinstance(item, UUID) else item)
                    for item in value
                ]


class BaseSchema(ma.SQLAlchemyAutoSchema):

    class Meta:
        load_instance = True
        include_relationships = True
        unknown = EXCLUDE

    def __init__(self, load_json=False, *args, **kwargs):
        self.load_json = load_json
        super(BaseSchema, self).__init__(*args, **kwargs)

    @post_load
    def make_instance(self, data, **kwargs):
        """Deserialize data to an instance of the model. Update an existing row
        if specified in `self.instance` or loaded by primary key(s) in the data;
        else create a new row.
        :param data: Data to deserialize.
        """
        if self.load_json:
            return data
        return super(BaseSchema, self).make_instance(data)


class UserSchema(BaseSchema):

    permissions = fields.Method("user_permissions", dump_only=True)
    password_changed_at = field_for(models.User, 'password_changed_at', format=DATETIME_FORMAT_NO_TIMEZONE)
    created_at = field_for(models.User, 'created_at', format=DATETIME_FORMAT_NO_TIMEZONE)
    auth_type = field_for(models.User, 'auth_type')
    password = fields.String(required=True, load_only=True)

    def user_permissions(self, usr):
        retval = {}
        for x in permission_dao.get_permissions_by_user_id(usr.id):
            service_id = str(x.service_id)
            if service_id not in retval:
                retval[service_id] = []
            retval[service_id].append(x.permission)
        return retval

    class Meta(BaseSchema.Meta):
        model = models.User
        exclude = (
            "_password",
            "created_at",
            "email_access_validated_at",
            "updated_at",
            "verify_codes",
        )

    @validates('name')
    def validate_name(self, value):
        if not value:
            raise ValidationError('Invalid name')

    @validates('email_address')
    def validate_email_address(self, value):
        try:
            validate_email_address(value)
        except InvalidEmailError as e:
            raise ValidationError(str(e))

    @validates('mobile_number')
    def validate_mobile_number(self, value):
        try:
            if value is not None:
                validate_phone_number(value, international=True)
        except InvalidPhoneError as error:
            raise ValidationError('Invalid phone number: {}'.format(error))


class UserUpdateAttributeSchema(BaseSchema):
    auth_type = field_for(models.User, 'auth_type')

    class Meta(BaseSchema.Meta):
        model = models.User
        exclude = (
            '_password',
            'created_at',
            'failed_login_count',
            'id',
            'logged_in_at',
            'password_changed_at',
            'platform_admin',
            'state',
            'updated_at',
            'verify_codes',
        )

    @validates('name')
    def validate_name(self, value):
        if not value:
            raise ValidationError('Invalid name')

    @validates('email_address')
    def validate_email_address(self, value):
        try:
            validate_email_address(value)
        except InvalidEmailError as e:
            raise ValidationError(str(e))

    @validates('mobile_number')
    def validate_mobile_number(self, value):
        try:
            if value is not None:
                validate_phone_number(value, international=True)
        except InvalidPhoneError as error:
            raise ValidationError('Invalid phone number: {}'.format(error))

    @validates_schema(pass_original=True)
    def check_unknown_fields(self, data, original_data, **kwargs):
        for key in original_data:
            if key not in self.fields:
                raise ValidationError('Unknown field name {}'.format(key))


class UserUpdatePasswordSchema(BaseSchema):

    class Meta(BaseSchema.Meta):
        model = models.User

    @validates_schema(pass_original=True)
    def check_unknown_fields(self, data, original_data, **kwargs):
        for key in original_data:
            if key not in self.fields:
                raise ValidationError('Unknown field name {}'.format(key))


class ProviderDetailsSchema(BaseSchema):
    created_by = fields.Nested(UserSchema, only=['id', 'name', 'email_address'], dump_only=True)

    class Meta(BaseSchema.Meta):
        model = models.ProviderDetails


class ProviderDetailsHistorySchema(BaseSchema):
    created_by = fields.Nested(UserSchema, only=['id', 'name', 'email_address'], dump_only=True)

    class Meta(BaseSchema.Meta):
        model = models.ProviderDetailsHistory


class ServiceSchema(BaseSchema, UUIDsAsStringsMixin):

    created_by = field_for(models.Service, 'created_by', required=True)
    organisation_type = field_for(models.Service, 'organisation_type')
    letter_logo_filename = fields.Method(dump_only=True, serialize='get_letter_logo_filename')
    permissions = fields.Method("service_permissions")
    email_branding = field_for(models.Service, 'email_branding')
    organisation = field_for(models.Service, 'organisation')
    override_flag = False
    go_live_at = field_for(models.Service, 'go_live_at', format=DATETIME_FORMAT_NO_TIMEZONE)
    allowed_broadcast_provider = fields.Method(dump_only=True, serialize='_get_allowed_broadcast_provider')
    broadcast_channel = fields.Method(dump_only=True, serialize='_get_broadcast_channel')

    def _get_allowed_broadcast_provider(self, service):
        return service.allowed_broadcast_provider

    def _get_broadcast_channel(self, service):
        return service.broadcast_channel

    def get_letter_logo_filename(self, service):
        return service.letter_branding and service.letter_branding.filename

    def service_permissions(self, service):
        return [p.permission for p in service.permissions]

    def get_letter_contact(self, service):
        return service.get_default_letter_contact()

    class Meta(BaseSchema.Meta):
        model = models.Service
        exclude = (
            'all_template_folders',
            'annual_billing',
            'api_keys',
            'broadcast_messages',
            'complaints',
            'contact_list',
            'created_at',
            'crown',
            'data_retention',
            'guest_list',
            'inbound_number',
            'inbound_sms',
            'jobs',
            'letter_contacts',
            'letter_logo_filename',
            'reply_to_email_addresses',
            'returned_letters',
            'service_broadcast_provider_restriction',
            'service_broadcast_settings',
            'service_sms_senders',
            'templates',
            'updated_at',
            'users',
            'version',
        )

    @validates('permissions')
    def validate_permissions(self, value):
        permissions = [v.permission for v in value]
        for p in permissions:
            if p not in models.SERVICE_PERMISSION_TYPES:
                raise ValidationError("Invalid Service Permission: '{}'".format(p))

        if len(set(permissions)) != len(permissions):
            duplicates = list(set([x for x in permissions if permissions.count(x) > 1]))
            raise ValidationError('Duplicate Service Permission: {}'.format(duplicates))

    @pre_load()
    def format_for_data_model(self, in_data, **kwargs):
        if isinstance(in_data, dict) and 'permissions' in in_data:
            str_permissions = in_data['permissions']
            permissions = []
            for p in str_permissions:
                permission = ServicePermission(service_id=in_data["id"], permission=p)
                permissions.append(permission)

            in_data['permissions'] = permissions


class DetailedServiceSchema(BaseSchema):
    statistics = fields.Dict()
    organisation_type = field_for(models.Service, 'organisation_type')

    class Meta(BaseSchema.Meta):
        model = models.Service
        exclude = (
            'all_template_folders',
            'annual_billing',
            'api_keys',
            'broadcast_messages',
            'contact_list',
            'created_by',
            'crown',
            'email_branding',
            'email_from',
            'guest_list',
            'inbound_api',
            'inbound_number',
            'inbound_sms',
            'jobs',
            'message_limit',
            'permissions',
            'rate_limit',
            'reply_to_email_addresses',
            'returned_letters',
            'service_sms_senders',
            'templates',
            'users',
            'version',
        )


class NotificationModelSchema(BaseSchema):
    class Meta(BaseSchema.Meta):
        model = models.Notification
        exclude = ('_personalisation', 'job', 'service', 'template', 'api_key',)

    status = fields.String(required=False)


class BaseTemplateSchema(BaseSchema):
    reply_to = fields.Method("get_reply_to", allow_none=True)
    reply_to_text = fields.Method("get_reply_to_text", allow_none=True)

    def get_reply_to(self, template):
        return template.reply_to

    def get_reply_to_text(self, template):
        return template.get_reply_to_text()

    class Meta(BaseSchema.Meta):
        model = models.Template
        exclude = ("service_id", "jobs", "service_letter_contact_id")


class TemplateSchema(BaseTemplateSchema, UUIDsAsStringsMixin):

    created_by = field_for(models.Template, 'created_by', required=True)
    process_type = field_for(models.Template, 'process_type')
    redact_personalisation = fields.Method("redact")

    def redact(self, template):
        return template.redact_personalisation

    @validates_schema
    def validate_type(self, data, **kwargs):
        if data.get('template_type') in {models.EMAIL_TYPE, models.LETTER_TYPE}:
            subject = data.get('subject')
            if not subject or subject.strip() == '':
                raise ValidationError('Invalid template subject', 'subject')


class TemplateSchemaNoDetail(TemplateSchema):
    class Meta(TemplateSchema.Meta):
        exclude = TemplateSchema.Meta.exclude + (
            'archived',
            'broadcast_data',
            'created_at',
            'created_by',
            'created_by_id',
            'hidden',
            'postage',
            'process_type',
            'redact_personalisation',
            'reply_to',
            'reply_to_text',
            'service',
            'service_letter_contact',
            'subject',
            'template_redacted',
            'updated_at',
            'version',
        )

    @pre_dump
    def remove_content_for_non_broadcast_templates(self, template, **kwargs):
        if template.template_type != models.BROADCAST_TYPE:
            template.content = None


class TemplateHistorySchema(BaseSchema):

    reply_to = fields.Method("get_reply_to", allow_none=True)
    reply_to_text = fields.Method("get_reply_to_text", allow_none=True)
    process_type = field_for(models.Template, 'process_type')

    created_by = fields.Nested(UserSchema, only=['id', 'name', 'email_address'], dump_only=True)
    created_at = field_for(models.Template, 'created_at', format=DATETIME_FORMAT_NO_TIMEZONE)

    def get_reply_to(self, template):
        return template.reply_to

    def get_reply_to_text(self, template):
        return template.get_reply_to_text()

    class Meta(BaseSchema.Meta):
        model = models.TemplateHistory
        exclude = ('broadcast_messages',)


class ApiKeySchema(BaseSchema):

    created_by = field_for(models.ApiKey, 'created_by', required=True)
    key_type = field_for(models.ApiKey, 'key_type', required=True)

    class Meta(BaseSchema.Meta):
        model = models.ApiKey
        exclude = ("service", "_secret")


class JobSchema(BaseSchema):
    created_by_user = fields.Nested(UserSchema, attribute="created_by",
                                    dump_to="created_by", only=["id", "name"], dump_only=True)
    created_by = field_for(models.Job, 'created_by', required=True, load_only=True)

    job_status = field_for(models.JobStatus, 'name', required=False)

    scheduled_for = fields.DateTime()
    service_name = fields.Nested(
        ServiceSchema, attribute="service", dump_to="service_name", only=["name"], dump_only=True)

    template_name = fields.Method('get_template_name', dump_only=True)
    template_type = fields.Method('get_template_type', dump_only=True)
    contact_list_id = field_for(models.Job, 'contact_list_id')

    def get_template_name(self, job):
        return job.template.name

    def get_template_type(self, job):
        return job.template.template_type

    @validates('scheduled_for')
    def validate_scheduled_for(self, value):
        _validate_datetime_not_in_past(value)
        _validate_datetime_not_more_than_96_hours_in_future(value)

    class Meta(BaseSchema.Meta):
        model = models.Job
        exclude = (
            'notifications',
            'notifications_delivered',
            'notifications_failed',
            'notifications_sent',
        )


class NotificationSchema(ma.Schema):
    class Meta:
        unknown = EXCLUDE

    status = fields.String(required=False)
    personalisation = fields.Dict(required=False)


class SmsNotificationSchema(NotificationSchema):
    to = fields.Str(required=True)

    @validates('to')
    def validate_to(self, value):
        try:
            validate_phone_number(value, international=True)
        except InvalidPhoneError as error:
            raise ValidationError('Invalid phone number: {}'.format(error))

    @post_load
    def format_phone_number(self, item, **kwargs):
        item['to'] = validate_and_format_phone_number(item['to'], international=True)
        return item


class EmailNotificationSchema(NotificationSchema):
    to = fields.Str(required=True)
    template = fields.Str(required=True)

    @validates('to')
    def validate_to(self, value):
        try:
            validate_email_address(value)
        except InvalidEmailError as e:
            raise ValidationError(str(e))


class SmsTemplateNotificationSchema(SmsNotificationSchema):
    template = fields.Str(required=True)
    job = fields.String()


class NotificationWithTemplateSchema(BaseSchema):
    class Meta(BaseSchema.Meta):
        model = models.Notification
        exclude = ('_personalisation',)

    template = fields.Nested(
        TemplateSchema,
        only=[
            'id',
            'version',
            'name',
            'template_type',
            'content',
            'subject',
            'redact_personalisation',
            'is_precompiled_letter'
        ],
        dump_only=True
    )
    job = fields.Nested(JobSchema, only=["id", "original_file_name"], dump_only=True)
    created_by = fields.Nested(UserSchema, only=['id', 'name', 'email_address'], dump_only=True)
    status = fields.String(required=False)
    personalisation = fields.Dict(required=False)
    key_type = field_for(models.Notification, 'key_type', required=True)
    key_name = fields.String()

    @pre_dump
    def add_api_key_name(self, in_data, **kwargs):
        if in_data.api_key:
            in_data.key_name = in_data.api_key.name
        else:
            in_data.key_name = None
        return in_data


class NotificationWithPersonalisationSchema(NotificationWithTemplateSchema):
    template_history = fields.Nested(TemplateHistorySchema, attribute="template",
                                     only=['id', 'name', 'template_type', 'content', 'subject', 'version'],
                                     dump_only=True)

    class Meta(NotificationWithTemplateSchema.Meta):
        # mark as many fields as possible as required since this is a public api.
        # WARNING: Does _not_ reference fields computed in handle_template_merge, such as
        # 'body', 'subject' [for emails], and 'content_char_count'
        fields = (
            # db rows
            'billable_units',
            'created_at',
            'id',
            'job_row_number',
            'notification_type',
            'reference',
            'sent_at',
            'sent_by',
            'status',
            'template_version',
            'to',
            'updated_at',
            # computed fields
            'personalisation',
            # relationships
            'api_key',
            'job',
            'service',
            'template_history',
        )
        # Overwrite the `NotificationWithTemplateSchema` base class to not exclude `_personalisation`, which
        # isn't a defined field for this class
        exclude = ()

    @pre_dump
    def handle_personalisation_property(self, in_data, **kwargs):
        self.personalisation = in_data.personalisation
        return in_data

    @post_dump
    def handle_template_merge(self, in_data, **kwargs):
        in_data['template'] = in_data.pop('template_history')
        template = get_template_instance(in_data['template'], in_data['personalisation'])
        in_data['body'] = template.content_with_placeholders_filled_in
        if in_data['template']['template_type'] != models.SMS_TYPE:
            in_data['subject'] = template.subject
            in_data['content_char_count'] = None
        else:
            in_data['content_char_count'] = template.content_count

        in_data.pop('personalisation', None)
        in_data['template'].pop('content', None)
        in_data['template'].pop('subject', None)
        return in_data


class InvitedUserSchema(BaseSchema):
    auth_type = field_for(models.InvitedUser, 'auth_type')

    class Meta(BaseSchema.Meta):
        model = models.InvitedUser

    @validates('email_address')
    def validate_to(self, value):
        try:
            validate_email_address(value)
        except InvalidEmailError as e:
            raise ValidationError(str(e))


class EmailDataSchema(ma.Schema):
    class Meta:
        unknown = EXCLUDE

    email = fields.Str(required=True)
    next = fields.Str(required=False)
    admin_base_url = fields.Str(required=False)

    def __init__(self, partial_email=False):
        super().__init__()
        self.partial_email = partial_email

    @validates('email')
    def validate_email(self, value):
        if self.partial_email:
            return
        try:
            validate_email_address(value)
        except InvalidEmailError as e:
            raise ValidationError(str(e))


class NotificationsFilterSchema(ma.Schema):
    class Meta:
        unknown = EXCLUDE

    template_type = fields.Nested(BaseTemplateSchema, only=['template_type'], many=True)
    status = fields.Nested(NotificationModelSchema, only=['status'], many=True)
    page = fields.Int(required=False)
    page_size = fields.Int(required=False)
    limit_days = fields.Int(required=False)
    include_jobs = fields.Boolean(required=False)
    include_from_test_key = fields.Boolean(required=False)
    older_than = fields.UUID(required=False)
    format_for_csv = fields.String()
    to = fields.String()
    include_one_off = fields.Boolean(required=False)
    count_pages = fields.Boolean(required=False)

    @pre_load
    def handle_multidict(self, in_data, **kwargs):
        if isinstance(in_data, dict) and hasattr(in_data, 'getlist'):
            out_data = dict([(k, in_data.get(k)) for k in in_data.keys()])
            if 'template_type' in in_data:
                out_data['template_type'] = [{'template_type': x} for x in in_data.getlist('template_type')]
            if 'status' in in_data:
                out_data['status'] = [{"status": x} for x in in_data.getlist('status')]

        return out_data

    @post_load
    def convert_schema_object_to_field(self, in_data, **kwargs):
        if 'template_type' in in_data:
            in_data['template_type'] = [x.template_type for x in in_data['template_type']]
        if 'status' in in_data:
            in_data['status'] = [x.status for x in in_data['status']]
        return in_data

    @validates('page')
    def validate_page(self, value):
        _validate_positive_number(value)

    @validates('page_size')
    def validate_page_size(self, value):
        _validate_positive_number(value)


class ServiceHistorySchema(ma.Schema):
    class Meta:
        unknown = EXCLUDE

    id = fields.UUID()
    name = fields.String()
    created_at = fields.DateTime()
    updated_at = fields.DateTime()
    active = fields.Boolean()
    message_limit = fields.Integer()
    restricted = fields.Boolean()
    email_from = fields.String()
    created_by_id = fields.UUID()
    version = fields.Integer()


class ApiKeyHistorySchema(ma.Schema):
    class Meta:
        unknown = EXCLUDE

    id = fields.UUID()
    name = fields.String()
    service_id = fields.UUID()
    expiry_date = fields.DateTime()
    created_at = fields.DateTime()
    updated_at = fields.DateTime()
    created_by_id = fields.UUID()


class EventSchema(BaseSchema):
    class Meta(BaseSchema.Meta):
        model = models.Event


class UnarchivedTemplateSchema(BaseSchema):
    archived = fields.Boolean(required=True)

    @validates_schema
    def validate_archived(self, data, **kwargs):
        if data['archived']:
            raise ValidationError('Template has been deleted', 'template')


# should not be used on its own for dumping - only for loading
create_user_schema = UserSchema()
user_update_schema_load_json = UserUpdateAttributeSchema(load_json=True, partial=True)
user_update_password_schema_load_json = UserUpdatePasswordSchema(only=('_password',), load_json=True, partial=True)
service_schema = ServiceSchema()
detailed_service_schema = DetailedServiceSchema()
template_schema = TemplateSchema()
template_schema_no_detail = TemplateSchemaNoDetail()
api_key_schema = ApiKeySchema()
job_schema = JobSchema()
sms_template_notification_schema = SmsTemplateNotificationSchema()
email_notification_schema = EmailNotificationSchema()
notification_schema = NotificationModelSchema()
notification_with_template_schema = NotificationWithTemplateSchema()
notification_with_personalisation_schema = NotificationWithPersonalisationSchema()
invited_user_schema = InvitedUserSchema()
email_data_request_schema = EmailDataSchema()
partial_email_data_request_schema = EmailDataSchema(partial_email=True)
notifications_filter_schema = NotificationsFilterSchema()
service_history_schema = ServiceHistorySchema()
api_key_history_schema = ApiKeyHistorySchema()
template_history_schema = TemplateHistorySchema()
event_schema = EventSchema()
provider_details_schema = ProviderDetailsSchema()
provider_details_history_schema = ProviderDetailsHistorySchema()
unarchived_template_schema = UnarchivedTemplateSchema()