from pathlib import Path

from flask import flash, redirect, request, url_for
from flask_admin import expose
from flask_admin.contrib.sqla.fields import QuerySelectField, QuerySelectMultipleField
from flask_admin.contrib.sqla.filters import BaseSQLAFilter
from flask_admin.helpers import get_form_data
from flask_admin.menu import MenuLink
from flask_admin.model.template import EndpointLinkRowAction
from flask_security import admin_change_password, current_user, hash_password
from flask_wtf import FlaskForm
from flask_wtf.file import FileAllowed, FileField, FileRequired
from sqlalchemy import and_, func, or_
from werkzeug.utils import secure_filename
from wtforms import BooleanField, Form, RadioField, SelectField, StringField
from wtforms.fields import DateField, IntegerField
from wtforms.validators import URL, DataRequired, Email, NumberRange, Optional

from advlabdb import adminSpace, app, assistantSpace, db, user_datastore
from advlabdb.configUtils import getConfig
from advlabdb.customClasses import SecureAdminBaseView, SecureAdminModelView
from advlabdb.database_import import importFromFile
from advlabdb.exceptions import DataBaseException, ModelViewException
from advlabdb.models import (
    Appointment,
    Assistant,
    Experiment,
    ExperimentMark,
    Group,
    GroupExperiment,
    Part,
    PartStudent,
    Program,
    Role,
    Semester,
    SemesterExperiment,
    Student,
    User,
)
from advlabdb.utils import (
    flashRandomPassword,
    initActiveSemesterMenuLinks,
    randomPassword,
    setUserActiveSemester,
    userActiveSemester,
)


def semesterExperimentQueryFactory():
    return SemesterExperiment.query.filter(SemesterExperiment.semester == userActiveSemester())


class UserView(SecureAdminModelView):
    class CreateForm(Form):
        def roleQueryFactory():
            return Role.query

        def semesterQueryFactory():
            return Semester.query

        def activeSemesterDefault():
            return userActiveSemester()

        email = StringField("Email", validators=[DataRequired(), Email()])
        roles = QuerySelectMultipleField(
            "Roles",
            query_factory=roleQueryFactory,
            validators=[DataRequired()],
            default=[Role.query.filter(Role.name == "assistant").first()],
        )

        first_name = StringField("First Name", validators=[DataRequired()])
        last_name = StringField("Last Name", validators=[DataRequired()])
        phone_number = StringField("Phone Number")
        mobile_phone_number = StringField("Mobile Phone Number")
        building = StringField("Building")
        room = StringField("Room")

        semester_experiments = QuerySelectMultipleField(
            "Semester Experiments",
            query_factory=semesterExperimentQueryFactory,
            allow_blank=True,
            blank_text="-",
            description="Only needed if the user has the assistant role",
        )

        active = BooleanField("Active", default=True)
        active_semester = QuerySelectField(
            "Active Semester",
            query_factory=semesterQueryFactory,
            allow_blank=True,
            blank_text="-",
            default=activeSemesterDefault,
            description="Not fixed and users (including assistants) can change it.",
        )

    class EditForm(CreateForm):
        semester_experiments = None

        generate_new_password = BooleanField("Generate new random password", default=False)

    form = EditForm

    can_view_details = True

    column_list = [
        "first_name",
        "last_name",
        "email",
        "active",
        "roles",
        "assistant",
        "active_semester",
    ]
    column_details_list = column_list + [
        "phone_number",
        "mobile_phone_number",
        "building",
        "room",
        "create_datetime",
        "update_datetime",
    ]
    column_searchable_list = [
        "first_name",
        "last_name",
        "email",
    ]
    column_filters = [
        "active",
        "active_semester",
    ]
    column_editable_list = [
        "active",
    ]

    def create_form(self, obj=None):
        form = self.CreateForm
        return form(get_form_data(), obj=obj)

    def create_model(self, form):
        try:
            password = randomPassword()
            hashedPassword = hash_password(password)

            email = form.email.data.lower()

            roles = [role.name for role in form.roles.data]

            model = user_datastore.create_user(
                email=email,
                password=hashedPassword,
                roles=roles,
                first_name=form.first_name.data,
                last_name=form.last_name.data,
                phone_number=form.phone_number.data,
                mobile_phone_number=form.mobile_phone_number.data,
                building=form.building.data,
                room=form.room.data,
                active=form.active.data,
                active_semester=form.active_semester.data,
            )

            self.on_model_change(form, model, True)
            self.session.commit()
        except Exception as ex:
            flash(str(ex), "error")

            self.session.rollback()
        else:
            flash(
                f"{email} registered with roles: {', '.join([role.name for role in model.roles])}.",
                category="success",
            )

            flashRandomPassword(password)

            self.after_model_change(form, model, True)
            return model

    def on_model_delete(self, model):
        if model == current_user:
            raise ModelViewException("Tried to delete yourself as user!")

    def on_model_change(self, form, model, is_created):
        if not is_created:
            if model == current_user:
                if not form.active.data:
                    raise ModelViewException("Tried to deactivate yourself as user!")
                if not model.has_role("admin"):
                    raise ModelViewException("Tried to remove your admin role!")

            if hasattr(form, "generate_new_password") and form.generate_new_password.data:
                password = randomPassword()
                UserView.flashPassword(password)

                admin_change_password(
                    model, password, notify=False
                )  # Password is automatically hashed with this function

        if model.has_role("assistant") and not model.assistant:
            semester_experiments = form.semester_experiments.data if form.semester_experiments else []

            assistant = Assistant(user=model, semester_experiments=semester_experiments)
            self.session.add(assistant)


class RoleView(SecureAdminModelView):
    can_create = False
    can_edit = False
    can_delete = False
    column_display_actions = False
    can_export = False
    can_set_page_size = False

    column_list = [
        "name",
        "description",
        "permissions",
        "update_datetime",
    ]


class SemesterView(SecureAdminModelView):
    class CreateForm(Form):
        def labelDefault():
            if userActiveSemester().label == "WS":
                return "SS"
            else:
                return "WS"

        def yearDefault():
            activeSemester = userActiveSemester()
            if activeSemester.label == "WS":
                return activeSemester.year + 1
            else:
                return activeSemester.year

        label = RadioField("Semester", choices=["WS", "SS"], validators=[DataRequired()], default=labelDefault)
        year = StringField("Year", validators=[DataRequired()], default=yearDefault)
        transfer_parts = BooleanField(
            "Transfer parts",
            description="This option transfers the parts you have in your current active semester. Make sure that your semester is the last semester before creating a new one (recommended)!",
            default=True,
        )
        transfer_assistants = BooleanField(
            "Transfer Assistants",
            description="This option transfers assistants of your active semester to active experiments in the new semester. Make sure that your semester is the last semester before creating a new one (recommended)! Active experiments are transferred anyway. If you do not want an experiment to be transferred, set it to inactive before creating the new semester. Experiments which are switched to active before creating the new semester will be created in the new semester without assistants. It is important to check the assistants of all experiments after creating a new semester.",
            default=True,
        )

    form = CreateForm

    can_edit = False
    can_delete = False
    can_view_details = True

    column_list = [
        "label",
        "year",
        "parts",
    ]
    column_details_list = column_list + [
        "semester_experiments",
        "active_users",
        "groups",
    ]
    column_searchable_list = [
        "label",
        "year",
    ]

    def customCreateModel(self, form):
        return Semester.customInitFromOldSemester(
            label=form.label.data,
            year=form.year.data,
            oldSemester=userActiveSemester(),
            transferParts=form.transfer_parts.data,
            transferAssistants=form.transfer_assistants.data,
        )

    def addMenuLink(space, newSemester):
        space.add_link(
            MenuLink(
                name=newSemester.repr(),
                url=url_for("set_semester") + "?semester_id=" + str(newSemester.id),
                category="Active semester",
            )
        )

    def after_model_change(self, form, model, is_created):
        setUserActiveSemester(model.id)

        SemesterView.addMenuLink(adminSpace, model)
        SemesterView.addMenuLink(assistantSpace, model)


def programQueryFactory():
    return Program.query


class PartView(SecureAdminModelView):
    can_view_details = True

    column_sortable_list = []
    column_list = [
        "program",
        "number",
        "semester",
    ]
    column_details_list = column_list + [
        "part_students",
    ]
    form_columns = [
        "program",
        "number",
    ]

    form_extra_fields = {
        "program": QuerySelectField(
            "Program", query_factory=programQueryFactory, validators=[DataRequired()], allow_blank=True, blank_text="-"
        )
    }

    def queryFilter(self):
        return Part.semester == userActiveSemester()

    def customCreateModel(self, form):
        return Part(program=form.program.data, number=form.number.data, semester=userActiveSemester())


class StudentView(SecureAdminModelView):
    can_view_details = True

    column_list = [
        "student_number",
        "first_name",
        "last_name",
        "uni_email",
        "contact_email",
        "part_students",
    ]
    column_descriptions = {
        "contact_email": "The preferred contact email address if entered by the student",
    }
    column_details_list = column_list + [
        "bachelor_thesis",
        "bachelor_thesis_work_group",
        "note",
    ]

    column_sortable_list = [
        "student_number",
        "first_name",
        "last_name",
    ]
    column_searchable_list = column_sortable_list + [
        "uni_email",
        "contact_email",
    ]

    form_excluded_columns = [
        "part_students",
    ]

    form_args = {
        "uni_email": {"validators": [Email()]},
        "contact_email": {"validators": [Email()]},
    }

    column_extra_row_actions = [
        EndpointLinkRowAction(
            "glyphicon glyphicon-time",
            id_arg="flt1_0",
            title="Experiments history",
            endpoint="experimentmark.index_view",
        )
    ]


def partQueryFactory():
    return Part.query.filter(Part.semester == userActiveSemester())


def groupQueryFactory():
    return Group.query.filter(Group.semester == userActiveSemester())


class PartStudentView(SecureAdminModelView):
    class CreateForm(Form):
        def studentQueryFactory():
            return Student.query

        student = QuerySelectField(
            "Student",
            query_factory=studentQueryFactory,
            validators=[DataRequired()],
            allow_blank=True,
            blank_text="-",
        )
        part = QuerySelectField(
            "Part",
            query_factory=partQueryFactory,
            validators=[DataRequired()],
            allow_blank=True,
            blank_text="-",
        )
        group = QuerySelectField(
            "Group",
            query_factory=groupQueryFactory,
            allow_blank=True,
            blank_text="-",
        )

    class EditForm(CreateForm):
        student = None
        part = None

    form = EditForm

    column_list = [
        "student",
        "part",
        "group",
        "final_part_mark",
        "experiment_marks",
    ]

    column_filters = [
        "part",
        "student",
        "group",
    ]

    def queryFilter(self):
        return PartStudent.part.has(Part.semester == userActiveSemester())

    def create_form(self, obj=None):
        form = self.CreateForm
        return form(get_form_data(), obj=obj)

    def on_model_change(self, form, model, is_created):
        PartStudent.check(model.group, model.part)


def partStudentQueryFactory():
    return PartStudent.query.filter(PartStudent.part.has(Part.semester == userActiveSemester()))


class GroupView(SecureAdminModelView):
    def formFactory(is_created, group):
        if is_created:

            def query_factory():
                return partStudentQueryFactory().filter(PartStudent.group == None)

        else:

            def query_factory():
                return partStudentQueryFactory().filter(
                    or_(
                        and_(PartStudent.group == None, PartStudent.part.has(Part.program == group.program)),
                        PartStudent.group == group,
                    )
                )

        class CustomForm(Form):
            part_students = QuerySelectMultipleField(
                "Part Students",
                query_factory=query_factory,
                validators=[DataRequired()],
                description="The part students have to be in the same program!",
            )

        return CustomForm

    column_list = [
        "number",
        "semester",
        "program",
        "part_students",
        "group_experiments",
    ]
    column_filters = [
        "number",
        "semester",
        "program",
    ]

    def queryFilter(self):
        return Group.semester == userActiveSemester()

    def customCreateModel(self, form):
        return Group.customInit(form.part_students.data)

    def create_form(self, obj=None):
        form = GroupView.formFactory(is_created=True, group=None)
        return form(get_form_data(), obj=obj)

    def edit_form(self, obj=None):
        form = GroupView.formFactory(is_created=False, group=obj)
        return form(get_form_data(), obj=obj)


class ExperimentView(SecureAdminModelView):
    can_view_details = True

    column_filters = [
        "active",
    ]
    column_list = [
        "number",
        "program",
        "title",
        "active",
    ]
    column_descriptions = {
        "active": "Active experiments are present in new semesters",
    }
    column_details_list = column_list + [
        "description",
        "wiki_link",
        "building",
        "room",
        "responsibility",
        "duration_in_days",
        "oral_weighting",
        "protocol_weighting",
        "final_weighting",
        "semester_experiments",
    ]

    form_columns = column_details_list.copy()
    form_columns.remove("semester_experiments")

    column_editable_list = [
        "active",
    ]

    form_args = {
        "wiki_link": {"validators": [URL()]},
        "oral_weighting": {
            "description": "Oral and protocol weighting have to add to 1! Both are rounded to 2 decimal digits."
        },
    }
    form_extra_fields = {
        "program": QuerySelectField(
            "Program", query_factory=programQueryFactory, validators=[DataRequired()], allow_blank=True, blank_text="-"
        )
    }

    def on_model_change(self, form, model, is_created):
        model.checkWeightings(roundWeightings=True)


def assistantQueryFactory():
    return Assistant.query.filter(Assistant.user.has(User.active == True))


class SemesterExperimentView(SecureAdminModelView):
    class CreateForm(Form):
        def experimentQueryFactory():
            return Experiment.query.filter(Experiment.active == True)

        experiment = QuerySelectField(
            "Experiment",
            query_factory=experimentQueryFactory,
            validators=[DataRequired()],
            allow_blank=True,
            blank_text="-",
        )

        assistants = QuerySelectMultipleField("Assistants", query_factory=assistantQueryFactory)

    form = CreateForm

    can_view_details = True

    column_list = [
        "experiment",
        "assistants",
        "semester",
    ]
    column_details_list = column_list + [
        "group_experiments",
    ]
    column_filters = [
        "experiment",
    ]

    def queryFilter(self):
        return SemesterExperiment.semester == userActiveSemester()

    def customCreateModel(self, form):
        return SemesterExperiment(
            semester=userActiveSemester(), experiment=form.experiment.data, assistants=form.assistants.data
        )


class AssistantView(SecureAdminModelView):
    def assistantUserQueryFactory():
        return User.query.filter(User.roles.any(Role.name == "assistant"))

    can_view_details = True

    column_list = [
        "user.first_name",
        "user.last_name",
        "user",
        "semester_experiments",
    ]
    column_details_list = column_list + [
        "user.phone_number",
        "user.mobile_phone_number",
        "user.building",
        "user.room",
        "appointments",
        "experiment_marks",
    ]
    column_searchable_list = [
        "user.first_name",
        "user.last_name",
        "user.email",
    ]
    column_filters = [
        "user.active",
    ]
    form_excluded_columns = [
        "experiment_marks",
        "appointments",
    ]

    form_extra_fields = {
        "user": QuerySelectField(
            "User",
            query_factory=assistantUserQueryFactory,
            validators=[DataRequired()],
            allow_blank=True,
            blank_text="-",
        ),
        "semester_experiments": QuerySelectMultipleField(
            "Semester Experiments",
            query_factory=semesterExperimentQueryFactory,
            allow_blank=True,
            blank_text="-",
        ),
    }


assistantBlankText = "Auto assign if experiment has only one assistant"


class GroupExperimentView(SecureAdminModelView):
    class CreateForm(Form):
        group = QuerySelectField(
            "Group",
            query_factory=groupQueryFactory,
            validators=[DataRequired()],
            allow_blank=True,
            blank_text="-",
        )
        semester_experiment = QuerySelectField(
            "Semester Experiment",
            query_factory=semesterExperimentQueryFactory,
            validators=[DataRequired()],
            allow_blank=True,
            blank_text="-",
        )

        appointment1_date = DateField(
            "Appointment-1 Date",
            validators=[Optional()],
            description="Set if you already want to add an appointment. Otherwise, leave it blank and you can do it later under the Appointment tab.",
        )
        appointment1_special = BooleanField("Appointment-1 Special", default=False)
        appointment1_assistant = QuerySelectField(
            "Appointment-1 Assistant",
            query_factory=assistantQueryFactory,
            allow_blank=True,
            blank_text=assistantBlankText,
        )

        appointment2_date = DateField(
            "Appointment-2 Date", validators=[Optional()], description="Add a second appointment (see above)."
        )
        appointment2_special = BooleanField("Appointment-2 Special", default=False)
        appointment2_assistant = QuerySelectField(
            "Appointment-2 Assistant",
            query_factory=assistantQueryFactory,
            allow_blank=True,
            blank_text=assistantBlankText,
        )

    form = CreateForm

    can_edit = False

    column_list = [
        "group",
        "semester_experiment",
        "appointments",
        "experiment_marks",
    ]
    column_filters = [
        "group",
        "semester_experiment.experiment",
        "appointments",
    ]

    def queryFilter(self):
        return GroupExperiment.group.has(Group.semester == userActiveSemester())

    def customCreateModel(self, form):
        return GroupExperiment.customInit(semester_experiment=form.semester_experiment.data, group=form.group.data)

    def on_model_change(self, form, model, is_created):
        if is_created:
            for date, special, assistant in zip(
                [form.appointment1_date.data, form.appointment2_date.data],
                [form.appointment1_special.data, form.appointment2_special.data],
                [form.appointment1_assistant.data, form.appointment2_assistant.data],
            ):
                if date:
                    appointment = Appointment.customInit(
                        date=date, special=special, group_experiment=model, assistant=assistant
                    )

                    self.session.add(appointment)

    def after_model_change(self, form, model, is_created):
        if is_created:
            if model.appointments:
                flash(f"Appointments {model.appointments} added.", "success")


def groupExperimentQueryFactory():
    return GroupExperiment.query.filter(
        GroupExperiment.semester_experiment.has(SemesterExperiment.semester == userActiveSemester())
    )


class AppointmentView(SecureAdminModelView):
    class CreateForm(Form):
        group_experiment = QuerySelectField(
            "Group Experiment",
            query_factory=groupExperimentQueryFactory,
            validators=[DataRequired()],
            allow_blank=True,
            blank_text="-",
        )
        date = DateField("Date", validators=[DataRequired()])
        special = BooleanField("Special", default=False)
        assistant = QuerySelectField(
            "Assistant",
            query_factory=assistantQueryFactory,
            allow_blank=True,
            blank_text=assistantBlankText,
        )

    form = CreateForm

    column_filters = [
        "date",
        "special",
        "group_experiment.group",
        "group_experiment.semester_experiment.experiment",
        "assistant.user",
    ]
    column_editable_list = [
        "date",
        "special",
    ]

    def queryFilter(self):
        return Appointment.group_experiment.has(
            GroupExperiment.semester_experiment.has(SemesterExperiment.semester == userActiveSemester())
        )

    def customCreateModel(self, form):
        return Appointment.customInit(
            date=form.date.data,
            special=form.special.data,
            group_experiment=form.group_experiment.data,
            assistant=form.assistant.data,
        )

    def update_model(self, form, model):
        if not form.date or not form.special:  # For editables
            return super().update_model(form, model)

        try:
            model.customUpdate(form.date.data, form.special.data, form.assistant.data, form.group_experiment.data)

            self.on_model_change(form, model, False)
            self.session.commit()
        except Exception as ex:
            flash(str(ex), "error")

            self.session.rollback()
            return False
        else:
            self.after_model_change(form, model, False)
            return True


class ExperimentMarkView(SecureAdminModelView):
    class StudentIdFilter(BaseSQLAFilter):
        def apply(self, query, value, alias=None):
            return query.filter(self.column == value)

        def operation(self):
            return "equals"

        def validate(self, value):
            if Student.query.get(value):
                return True
            else:
                return False

    class CreateForm(Form):
        part_student = QuerySelectField(
            "Part Student",
            query_factory=partStudentQueryFactory,
            validators=[DataRequired()],
            allow_blank=True,
            blank_text="-",
        )
        group_experiment = QuerySelectField(
            "Group Experiment",
            query_factory=groupExperimentQueryFactory,
            validators=[DataRequired()],
            allow_blank=True,
            blank_text="-",
        )

    class EditForm(Form):
        oral_mark = IntegerField(
            "Oral Mark",
            validators=[NumberRange(min=0, max=15), Optional()],
            description="Between 0 and 15",
        )
        protocol_mark = IntegerField(
            "Protocol Mark",
            validators=[NumberRange(min=0, max=15), Optional()],
            description="Between 0 and 15",
        )

    form = EditForm

    column_descriptions = {
        "oral_mark": "Between 0 and 15",
        "protocol_mark": "Between 0 and 15",
        "final_experiment_mark": "Calculated automatically with oral and protocol marks and weightings",
        "assistant": "The assistant who assigned the mark",
        "edited_by_admin": "If the mark was edited by an admin",
    }

    column_filters = [
        StudentIdFilter(PartStudent.id, "Student / ID"),
        "part_student.part.program",
        "part_student.part",
        "part_student.student",
        "group_experiment.group",
        "group_experiment.semester_experiment.semester",
        "group_experiment.semester_experiment.experiment",
        "edited_by_admin",
        "assistant.user",
        "oral_mark",
        "protocol_mark",
        "final_experiment_mark",
    ]
    column_default_sort = [("oral_mark", False), ("protocol_mark", False)]

    """
    # Deactivated for the experiments history of a student.
    def queryFilter(self):
        return ExperimentMark.group_experiment.has(
            GroupExperiment.semester_experiment.has(SemesterExperiment.semester == userActiveSemester())
        )
    """

    def create_form(self, obj=None):
        form = self.CreateForm
        return form(get_form_data(), obj=obj)

    def customCreateModel(self, form):
        return ExperimentMark.customInit(
            part_student=form.part_student.data, group_experiment=form.group_experiment.data
        )

    def update_model(self, form, model):
        if (form.oral_mark and form.oral_mark.data != model.oral_mark) or (
            form.protocol_mark and form.protocol_mark.data != model.protocol_mark
        ):
            model.edited_by_admin = True

            ret = super().update_model(form, model)

            model.part_student.checkThenSetFinalPartMark()

            return ret
        else:
            # Nothing changed
            return True


class ProgramView(SecureAdminModelView):
    can_view_details = True

    column_list = [
        "label",
    ]
    form_excluded_columns = [
        "parts",
        "experiments",
        "groups",
    ]
    column_details_list = column_list + form_excluded_columns


class ImportView(SecureAdminBaseView):
    class FileForm(FlaskForm):
        file = FileField(
            label="Import file",
            validators=[FileRequired(), FileAllowed(["txt"], "Only txt files are allowed!")],
            description="The import file has to be a text file (with .txt at the end) encoded in UTF-8. It has to strictly follow the required format.",
        )

    @expose(methods=("GET", "POST"))
    def index(self):
        form = ImportView.FileForm()

        if form.validate_on_submit():
            f = form.file.data
            filename = secure_filename(f.filename)

            directory = "db/import_files"
            Path(directory).mkdir(exist_ok=True)

            filePath = directory + f"/{filename}"
            f.save(filePath)

            try:
                importFromFile(filePath)
            except Exception as exc:
                flash(str(exc), "error")

            return redirect(url_for("index"))

        return self.render("import.html", form=form)


class DocsView(SecureAdminBaseView):
    @expose()
    def index(self):
        return self.render("docs/admin.html")


adminSpace.add_view(StudentView(Student, db.session))
adminSpace.add_view(PartStudentView(PartStudent, db.session))
adminSpace.add_view(GroupView(Group, db.session))
adminSpace.add_view(GroupExperimentView(GroupExperiment, db.session))
adminSpace.add_view(AppointmentView(Appointment, db.session))
adminSpace.add_view(ExperimentMarkView(ExperimentMark, db.session))
adminSpace.add_view(ExperimentView(Experiment, db.session))
adminSpace.add_view(SemesterExperimentView(SemesterExperiment, db.session))
adminSpace.add_view(SemesterView(Semester, db.session))
adminSpace.add_view(PartView(Part, db.session))
adminSpace.add_view(AssistantView(Assistant, db.session))
adminSpace.add_view(UserView(User, db.session))
adminSpace.add_view(RoleView(Role, db.session))
adminSpace.add_view(ProgramView(Program, db.session))
adminSpace.add_view(ImportView(name="Import"))
adminSpace.add_view(DocsView(name="Docs"))

initActiveSemesterMenuLinks(adminSpace)