__copyright__ = "Copyright (C) 2014 Andreas Kloeckner"

__license__ = """
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 typing import Any, Tuple

from django import forms
from django.contrib import admin
from django.utils.translation import gettext_lazy as _, pgettext

from course.constants import exam_ticket_states, participation_permission as pperm
from course.enrollment import approve_enrollment, deny_enrollment
from course.models import (
    AuthenticationToken, Course, Event, Exam, ExamTicket, FlowPageData,
    FlowPageVisit, FlowPageVisitGrade, FlowRuleException, FlowSession, GradeChange,
    GradingOpportunity, InstantFlowRequest, InstantMessage, Participation,
    ParticipationPermission, ParticipationPreapproval, ParticipationRole,
    ParticipationRolePermission, ParticipationTag,
)
from relate.utils import string_concat


# {{{ permission helpers

def _filter_courses_for_user(queryset, user):
    if user.is_superuser:
        return queryset
    z = queryset.filter(
            participations__user=user,
            participations__roles__permissions__permission=pperm.use_admin_interface)
    return z


def _filter_course_linked_obj_for_user(queryset, user):
    if user.is_superuser:
        return queryset
    return queryset.filter(
            course__participations__user=user,
            course__participations__roles__permissions__permission  # noqa
            =pperm.use_admin_interface
            )


def _filter_participation_linked_obj_for_user(queryset, user):
    if user.is_superuser:
        return queryset
    return queryset.filter(
        participation__course__participations__user=user,
        participation__course__participations__roles__permissions__permission  # noqa
        =pperm.use_admin_interface)

# }}}


# {{{ list filter helper

def _filter_related_only(filter_arg: str) -> Tuple[str, Any]:
    return (filter_arg, admin.RelatedOnlyFieldListFilter)

# }}}


# {{{ course

class UnsafePasswordInput(forms.TextInput):
    # This sends passwords back to the user--not ideal, but OK for the XMPP
    # password.
    input_type = "password"


class CourseAdminForm(forms.ModelForm):
    class Meta:
        model = Course
        widgets = {
                "course_xmpp_password": UnsafePasswordInput
                }
        exclude = ()


@admin.register(Course)
class CourseAdmin(admin.ModelAdmin):
    list_display = (
            "identifier",
            "number",
            "name",
            "time_period",
            "start_date",
            "end_date",
            "hidden",
            "listed",
            "accepts_enrollment")
    list_editable = (
            "number",
            "name",
            "time_period",
            "start_date",
            "end_date",
            "hidden",
            "listed",
            "accepts_enrollment")
    list_filter = (
            "number",
            "time_period",
            "hidden",
            "listed",
            "accepts_enrollment")
    date_hierarchy = "start_date"

    search_fields = (
            "identifier",
            "number",
            "name",
            "time_period")

    readonly_fields = ("identifier",)

    form = CourseAdminForm

    save_on_top = True

    # {{{ permissions

    def has_add_permission(self, request):
        # These are created only through the course creation form.
        return False

    def get_queryset(self, request):
        qs = super().get_queryset(request)
        return _filter_courses_for_user(qs, request.user)

    # }}}

# }}}


# {{{ events

@admin.register(Event)
class EventAdmin(admin.ModelAdmin):
    list_display = (
            "course",
            "kind",
            "ordinal",
            "time",
            "end_time",
            "shown_in_calendar")
    list_filter = (_filter_related_only("course"), "kind", "shown_in_calendar")

    date_hierarchy = "time"

    search_fields = (
            "course__identifier",
            "kind",
            )

    def __unicode__(self):  # pragma: no cover  # not used
        return "{}{} in {}".format(
            self.kind,
            " (%s)" % str(self.ordinal) if self.ordinal is not None else "",
            self.course)

    __str__ = __unicode__

    list_editable = ("ordinal", "time", "end_time", "shown_in_calendar")

    # {{{ permissions

    def get_queryset(self, request):
        qs = super().get_queryset(request)
        return _filter_course_linked_obj_for_user(qs, request.user)

    def formfield_for_foreignkey(self, db_field, request, **kwargs):
        if db_field.name == "course":
            kwargs["queryset"] = _filter_courses_for_user(
                    Course.objects, request.user)
        return super().formfield_for_foreignkey(
                db_field, request, **kwargs)

    # }}}

# }}}


# {{{ participation tags

@admin.register(ParticipationTag)
class ParticipationTagAdmin(admin.ModelAdmin):
    list_filter = (_filter_related_only("course"),)

    # {{{ permissions

    def get_queryset(self, request):
        qs = super().get_queryset(request)
        return _filter_course_linked_obj_for_user(qs, request.user)

    def formfield_for_foreignkey(self, db_field, request, **kwargs):
        if db_field.name == "course":
            kwargs["queryset"] = _filter_courses_for_user(
                    Course.objects, request.user)
        return super().formfield_for_foreignkey(
                db_field, request, **kwargs)

    # }}}

# }}}


# {{{ participations

class ParticipationRolePermissionInline(admin.TabularInline):
    model = ParticipationRolePermission
    extra = 3


@admin.register(ParticipationRole)
class ParticipationRoleAdmin(admin.ModelAdmin):
    inlines = (ParticipationRolePermissionInline,)

    list_filter = (_filter_related_only("course"), "identifier")

    def get_queryset(self, request):
        qs = super().get_queryset(request)
        if request.user.is_superuser:
            return qs
        return _filter_course_linked_obj_for_user(qs, request.user)


class ParticipationPermissionInline(admin.TabularInline):
    model = ParticipationPermission
    extra = 3


class ParticipationForm(forms.ModelForm):
    class Meta:
        model = Participation
        exclude = ("role",)

    def clean(self):
        super().clean()

        for tag in self.cleaned_data.get("tags", []):
            if tag.course != self.cleaned_data.get("course"):
                from django.core.exceptions import ValidationError
                raise ValidationError(
                    {"tags": _("Tags must belong to same course as "
                               "participation.")})

        for role in self.cleaned_data.get("roles", []):
            if role.course != self.cleaned_data.get("course"):
                from django.core.exceptions import ValidationError
                raise ValidationError(
                    {"roles": _("Role must belong to same course as "
                               "participation.")})


@admin.register(Participation)
class ParticipationAdmin(admin.ModelAdmin):
    form = ParticipationForm

    @admin.display(
        description=_("Roles")
    )
    def get_roles(self, obj):
        return ", ".join(str(role.name) for role in obj.roles.all())

    @admin.display(
        description=_("Tags")
    )
    def get_tags(self, obj):
        return ", ".join(str(tag.name) for tag in obj.tags.all())

    # Fixme: This can be misleading when Non-superuser click on the
    # link of a user who also attend other courses.
    @admin.display(
        description=pgettext("real name of a user", "Name"),
        ordering="user__last_name",
    )
    def get_user(self, obj):
        from django.conf import settings
        from django.urls import reverse
        from django.utils.html import mark_safe

        return mark_safe(string_concat(
                "<a href='%(link)s'>", "%(user_fullname)s",
                "</a>"
                ) % {
                    "link": reverse(
                        "admin:%s_change"
                        % settings.AUTH_USER_MODEL.replace(".", "_")
                        .lower(),
                        args=(obj.user.id,)),
                    "user_fullname": obj.user.get_full_name(
                        force_verbose_blank=True),
                    })

    list_display = (
            "user",
            "get_user",
            "course",
            "get_roles",
            "status",
            "get_tags",
            )

    def get_list_filter(self, request):
        if request is not None and request.user.is_superuser:
            return ("course",
                    "roles__name",
                    "status",
                    "tags")
        return (_filter_related_only("course"),
                   _filter_related_only("roles"),
                   "status",
                   _filter_related_only("tags"))

    raw_id_fields = ("user",)

    filter_horizontal = ("tags", "roles",)

    search_fields = (
            "course__identifier",
            "user__username",
            "user__first_name",
            "user__last_name",
            )

    actions = [approve_enrollment, deny_enrollment]

    inlines = (ParticipationPermissionInline,)

    save_on_top = True

    # {{{ permissions

    def get_queryset(self, request):
        qs = super().get_queryset(request)
        return _filter_course_linked_obj_for_user(qs, request.user)

    def formfield_for_foreignkey(self, db_field, request, **kwargs):
        if db_field.name == "course":
            kwargs["queryset"] = _filter_courses_for_user(
                    Course.objects, request.user)

        # Fixme: This seems not to be not reachable
        if db_field.name == "tags":
            kwargs["queryset"] = _filter_course_linked_obj_for_user(
                    ParticipationTag.objects, request.user)
        return super().formfield_for_foreignkey(
                db_field, request, **kwargs)

    # }}}


@admin.register(ParticipationPreapproval)
class ParticipationPreapprovalAdmin(admin.ModelAdmin):
    @admin.display(
        description=_("Roles")
    )
    def get_roles(self, obj):
        return ", ".join(str(role.name) for role in obj.roles.all())

    list_display = ("email", "institutional_id", "course", "get_roles",
            "creation_time", "creator")
    list_filter = (_filter_related_only("course"), _filter_related_only("roles"))

    search_fields = (
            "email", "institutional_id",
            )

    # {{{ permissions

    def get_queryset(self, request):
        qs = super().get_queryset(request)
        if request.user.is_superuser:
            return qs
        return _filter_course_linked_obj_for_user(qs, request.user)

    exclude = ("creator", "creation_time", "role")

    def save_model(self, request, obj, form, change):
        obj.creator = request.user
        obj.save()

    def formfield_for_foreignkey(self, db_field, request, **kwargs):
        if db_field.name == "course":
            kwargs["queryset"] = _filter_courses_for_user(
                    Course.objects, request.user)
        return super().formfield_for_foreignkey(
                db_field, request, **kwargs)

    # }}}

# }}}


@admin.register(AuthenticationToken)
class AuthenticationTokenAdmin(admin.ModelAdmin):
    list_display = ("id", "participation", "restrict_to_participation_role",
            "description", "valid_until", "revocation_time")

    date_hierarchy = "creation_time"

    search_fields = (
            "id", "description", "participation__user__username"
            )


@admin.register(InstantFlowRequest)
class InstantFlowRequestAdmin(admin.ModelAdmin):
    list_display = ("course", "flow_id", "start_time", "end_time", "cancelled")
    list_filter = (_filter_related_only("course"),)

    date_hierarchy = "start_time"

    search_fields = (
            "email",
            )


# {{{ flow sessions

class FlowPageDataInline(admin.TabularInline):
    model = FlowPageData
    extra = 0


@admin.register(FlowSession)
class FlowSessionAdmin(admin.ModelAdmin):
    @admin.display(
        description=_("Participant"),
        ordering="participation__user",
    )
    def get_participant(self, obj):
        if obj.participation is None:
            return None

        return obj.participation.user

    search_fields = (
            "=id",
            "flow_id",
            "access_rules_tag",
            "participation__user__username",
            "participation__user__first_name",
            "participation__user__last_name",
            "user__username",
            "user__first_name",
            "user__last_name",
            )

    list_display = (
            "id",
            "flow_id",
            "get_participant",
            "course",
            "start_time",
            "completion_time",
            "access_rules_tag",
            "in_progress",
            #"expiration_mode",
            )
    list_display_links = (
            "flow_id",
            "get_participant",
            )

    date_hierarchy = "start_time"

    list_filter = (
            _filter_related_only("course"),
            "flow_id",
            "in_progress",
            "access_rules_tag",
            "expiration_mode",
            )

    inlines = (FlowPageDataInline,)

    raw_id_fields = ("participation", "user")

    save_on_top = True

    # {{{ permissions

    def has_add_permission(self, request):
        # These are only created automatically.
        return False

    def get_queryset(self, request):
        qs = super().get_queryset(request)
        return _filter_course_linked_obj_for_user(qs, request.user)

    def formfield_for_foreignkey(self, db_field, request, **kwargs):
        if db_field.name == "course":
            kwargs["queryset"] = _filter_courses_for_user(
                    Course.objects, request.user)
        return super().formfield_for_foreignkey(
                db_field, request, **kwargs)

    # }}}

# }}}


# {{{ flow page visit

class FlowPageVisitGradeInline(admin.TabularInline):
    model = FlowPageVisitGrade
    extra = 0


class HasAnswerListFilter(admin.SimpleListFilter):
    title = "has answer"

    parameter_name = "has_answer"

    def lookups(self, request, model_admin):
        return (
            ("y", _("Yes")),
            ("n", _("No")),
        )

    def queryset(self, request, queryset):
        if self.value() is None:
            return queryset
        return queryset.filter(answer__isnull=self.value() != "y")


class FlowIdListFilter(admin.SimpleListFilter):
    """
    This is only necessary when flow_id is only accessible by FlowSession, which is
    a ForeignKey in the model
    """
    title = _("Flow ID")
    parameter_name = "flow_id"

    def lookups(self, request, model_admin):
        qs = model_admin.get_queryset(request)
        if not request.user.is_superuser:
            qs = qs.filter(
                flow_session__course__participations__user=request.user,
                flow_session__course__participations__roles__permissions__permission  # noqa
                =pperm.use_admin_interface)

        flow_ids = qs.values_list("flow_session__flow_id", flat=True).distinct()
        return zip(flow_ids, flow_ids)

    def queryset(self, request, queryset):
        if self.value():
            return queryset.filter(flow_session__flow_id=self.value())
        else:
            return queryset


@admin.register(FlowPageVisit)
class FlowPageVisitAdmin(admin.ModelAdmin):
    @admin.display(
        description=_("Course"),
        ordering="flow_session__course",
    )
    def get_course(self, obj):
        return obj.flow_session.course

    @admin.display(
        description=_("Flow ID"),
        ordering="flow_session__flow_id",
    )
    def get_flow_id(self, obj):
        return obj.flow_session.flow_id

    @admin.display(
        description=_("Page ID"),
        ordering="page_data__page_id",
    )
    def get_page_id(self, obj):
        if obj.page_data.page_ordinal is None:
            return string_concat("%s/%s (", _("not in use"), ")") % (
                    obj.page_data.group_id,
                    obj.page_data.page_id)
        else:
            return "{}/{} ({})".format(
                    obj.page_data.group_id,
                    obj.page_data.page_id,
                    obj.page_data.page_ordinal)

    @admin.display(
        description=_("Owner"),
        ordering="flow_session__participation",
    )
    def get_participant(self, obj):
        if obj.flow_session.participation:
            return obj.flow_session.participation.user
        else:
            return string_concat("(", _("anonymous"), ")")

    @admin.display(
        description=_("Has answer"),
        boolean=True,
    )
    def get_answer_is_null(self, obj):
        return obj.answer is not None

    @admin.display(
        description=_("Flow Session ID"),
        ordering="flow_session__id",
    )
    def get_flow_session_id(self, obj):
        return obj.flow_session.id

    list_filter = (
            HasAnswerListFilter,
            "is_submitted_answer",
            "is_synthetic",
            _filter_related_only("flow_session__participation__course"),
            FlowIdListFilter,
            )
    date_hierarchy = "visit_time"
    list_display = (
            "id",
            "get_course",
            "get_flow_id",
            "get_page_id",
            "get_participant",
            "get_flow_session_id",
            "visit_time",
            "get_answer_is_null",
            "is_submitted_answer",
            "is_synthetic",
            "user",
            "impersonated_by",
            )
    list_display_links = (
            "id",
            )

    search_fields = (
            "=id",
            "=flow_session__id",
            "flow_session__flow_id",
            "page_data__group_id",
            "page_data__page_id",
            "flow_session__participation__user__username",
            "flow_session__participation__user__first_name",
            "flow_session__participation__user__last_name",
            )

    raw_id_fields = ("flow_session", "page_data")

    inlines = (FlowPageVisitGradeInline,)

    save_on_top = True

    # {{{ permissions

    def has_add_permission(self, request):
        # These are created only automatically.
        return False

    def get_queryset(self, request):
        qs = super().get_queryset(request)
        if request.user.is_superuser:
            return qs
        return qs.filter(
            flow_session__course__participations__user=request.user,
            flow_session__course__participations__roles__permissions__permission  # noqa
            =pperm.use_admin_interface)

    # }}}

# }}}


# {{{ flow access

@admin.register(FlowRuleException)
class FlowRuleExceptionAdmin(admin.ModelAdmin):
    @admin.display(
        description=_("Course"),
        ordering="participation__course",
    )
    def get_course(self, obj):
        return obj.participation.course

    @admin.display(
        description=_("Participant"),
        ordering="participation__user",
    )
    def get_participant(self, obj):
        return obj.participation.user

    ordering = ("-creation_time",)

    search_fields = (
            "flow_id",
            "participation__user__username",
            "participation__user__first_name",
            "participation__user__last_name",
            "comment",
            )

    list_display = (
            "get_participant",
            "get_course",
            "flow_id",
            "kind",
            "expiration",
            "creation_time",
            )
    list_display_links = (
            "get_participant",
            "flow_id",
            )
    list_filter = (
            _filter_related_only("participation__course"),
            "flow_id",
            "kind",
            )

    date_hierarchy = "creation_time"

    raw_id_fields = ("participation",)

    # {{{ permissions

    def has_add_permission(self, request):
        # These are only created automatically.
        return False

    def get_queryset(self, request):
        qs = super().get_queryset(request)
        return _filter_participation_linked_obj_for_user(qs, request.user)

    exclude = ("creator", "creation_time")

    def save_model(self, request, obj, form, change):  # pragma: no cover
        # This won't work since it's not allowed to add
        obj.creator = request.user
        obj.save()

    # }}}

# }}}


# {{{ grading

@admin.register(GradingOpportunity)
class GradingOpportunityAdmin(admin.ModelAdmin):
    list_display = (
            "name",
            "course",
            "identifier",
            "due_time",
            "shown_in_grade_book",
            "shown_in_participant_grade_book",
            )
    list_filter = (
            _filter_related_only("course"),
            "shown_in_grade_book",
            "shown_in_participant_grade_book",
            )
    list_editable = (
            "shown_in_grade_book",
            "shown_in_participant_grade_book",
            )

    # {{{ permissions

    exclude = ("creation_time",)

    def get_queryset(self, request):
        qs = super().get_queryset(request)
        return _filter_course_linked_obj_for_user(qs, request.user)

    def formfield_for_foreignkey(self, db_field, request, **kwargs):
        if db_field.name == "course":
            kwargs["queryset"] = _filter_courses_for_user(
                    Course.objects, request.user)
        return super().formfield_for_foreignkey(
                db_field, request, **kwargs)

    # }}}


@admin.register(GradeChange)
class GradeChangeAdmin(admin.ModelAdmin):
    @admin.display(
        description=_("Course"),
        ordering="participation__course",
    )
    def get_course(self, obj):
        return obj.participation.course

    @admin.display(
        description=_("Opportunity"),
        ordering="opportunity",
    )
    def get_opportunity(self, obj):
        return obj.opportunity.name

    @admin.display(
        description=_("Participant"),
        ordering="participation__user",
    )
    def get_participant(self, obj):
        return obj.participation.user

    @admin.display(
        description="%"
    )
    def get_percentage(self, obj):
        if obj.points is None or not obj.max_points:
            return None
        else:
            return round(100*obj.points/obj.max_points)

    list_display = (
            "get_opportunity",
            "get_participant",
            "get_course",
            "state",
            "points",
            "max_points",
            "get_percentage",
            "attempt_id",
            "grade_time",
            )
    list_display_links = (
            "get_opportunity",
            "get_participant",
            )
    date_hierarchy = "grade_time"

    search_fields = (
            "opportunity__name",
            "opportunity__flow_id",
            "opportunity__identifier",
            "participation__user__username",
            "participation__user__first_name",
            "participation__user__last_name",
            "attempt_id",
            )

    list_filter = (
            _filter_related_only("opportunity__course"),
            _filter_related_only("opportunity"),
            "state",
            )

    raw_id_fields = ("participation", "flow_session", "opportunity")

    # {{{ permission

    def get_queryset(self, request):
        qs = super().get_queryset(request)
        return _filter_participation_linked_obj_for_user(qs, request.user)

    exclude = ("creator", "grade_time")

    def save_model(self, request, obj, form, change):
        obj.creator = request.user
        obj.save()

    # }}}

# }}}


# {{{ instant message

@admin.register(InstantMessage)
class InstantMessageAdmin(admin.ModelAdmin):
    @admin.display(
        description=_("Course"),
        ordering="participation__course",
    )
    def get_course(self, obj):
        return obj.participation.course

    @admin.display(
        description=_("Participant"),
        ordering="participation__user",
    )
    def get_participant(self, obj):
        return obj.participation.user

    list_filter = (_filter_related_only("participation__course"),)
    list_display = (
            "get_course",
            "get_participant",
            "time",
            "text",
            )

    date_hierarchy = "time"

    search_fields = (
            "text",
            "participation__user__username",
            "participation__user__first_name",
            "participation__user__last_name",
            )

    raw_id_fields = ("participation",)

    # {{{ permissions

    def has_add_permission(self, request):
        # These are created only automatically.
        return False

    def get_queryset(self, request):
        qs = super().get_queryset(request)
        return _filter_participation_linked_obj_for_user(qs, request.user)

    # }}}

# }}}


# {{{ exam tickets

@admin.register(Exam)
class ExamAdmin(admin.ModelAdmin):
    list_filter = (
            _filter_related_only("course"),
            "active",
            "listed",
            )

    list_display = (
            "course",
            "flow_id",
            "active",
            "listed",
            "no_exams_before",
            )

    search_fields = (
            "flow_id",
            )

    date_hierarchy = "no_exams_before"

    # {{{ permissions

    def get_queryset(self, request):
        qs = super().get_queryset(request)
        return _filter_course_linked_obj_for_user(qs, request.user)

    def formfield_for_foreignkey(self, db_field, request, **kwargs):
        if db_field.name == "course":
            kwargs["queryset"] = _filter_courses_for_user(
                    Course.objects, request.user)
        return super().formfield_for_foreignkey(
                db_field, request, **kwargs)

    # }}}


@admin.register(ExamTicket)
class ExamTicketAdmin(admin.ModelAdmin):
    @admin.display(
        description=_("Course"),
        ordering="participation__course",
    )
    def get_course(self, obj):
        return obj.participation.course

    list_filter = (
            _filter_related_only("participation__course"),
            "state",
            )

    raw_id_fields = ("participation",)

    list_display = (
            "get_course",
            "exam",
            "participation",
            "state",
            "creation_time",
            "usage_time",
            )

    date_hierarchy = "usage_time"

    search_fields = (
            "exam__course__identifier",
            "exam__flow_id",
            "exam__description",
            "participation__user__username",
            "participation__user__first_name",
            "participation__user__last_name",
            )

    # {{{ permissions

    def get_queryset(self, request):
        qs = super().get_queryset(request)
        return _filter_participation_linked_obj_for_user(qs, request.user)

    exclude = ("creator",)

    def save_model(self, request, obj, form, change):
        obj.creator = request.user
        obj.save()

    # }}}

    @admin.action(
        description=_("Revoke Exam Tickets")
    )
    def revoke_exam_tickets(self, request, queryset):  # noqa
        queryset \
                .filter(state=exam_ticket_states.valid) \
                .update(state=exam_ticket_states.revoked)

    actions = [revoke_exam_tickets]

# }}}

# vim: foldmethod=marker
