from django.contrib import messages
from django.contrib.auth.decorators import login_required
from django.utils.translation import gettext_lazy as _
from django.http import HttpRequest
from django.shortcuts import render, get_object_or_404, redirect
from django.urls import reverse

from intervention.forms import NewInterventionForm, EditInterventionForm, OpenInterventionForm
from intervention.models import Intervention
from intervention.tables import InterventionTable
from konova.contexts import BaseContext
from konova.decorators import *
from konova.forms import RemoveForm
from process.models import Process


@login_required
@resolve_user_role
def index_view(request: HttpRequest):
    """
    Renders the index view for process

    Args:
        request (HttpRequest): The incoming request

    Returns:
        A rendered view
    """
    template = "generic_index.html"
    user = request.user
    interventions = Intervention.get_role_objects(user)
    table = InterventionTable(
        request=request,
        queryset=interventions
    )
    context = {
        "table": table,
    }
    context = BaseContext(request, context).context
    return render(request, template, context)


@login_required
def new_view(request: HttpRequest):
    """
    Renders a view for a new intervention creation

    Args:
        request (HttpRequest): The incoming request

    Returns:

    """
    template = "konova/form.html"
    form = NewInterventionForm(request.POST or None)
    if request.method == "POST":
        if form.is_valid():
            intervention = form.save(request.user)
            if intervention.process is None:
                # An intervention can not be created without a process -> automatically create a new process
                process = Process.create_from_intervention(intervention)
                messages.info(request, _("Interventions must be part of a process. Please fill in the missing data for the process"))
                return redirect("process:edit", id=process.id)
            else:
                messages.success(request, _("Intervention {} added").format(intervention.title))
                return redirect("intervention:index")
        else:
            messages.error(request, _("Invalid input"))
    else:
        # For clarification: nothing in this case
        pass
    context = {
        "form": form,
    }
    context = BaseContext(request, context).context
    return render(request, template, context)


@login_required
def open_view(request: HttpRequest, id: str):
    """ Renders a view for viewing an intervention's data

    Args:
        request (HttpRequest): The incoming request
        id (str): The intervention's id

    Returns:

    """
    template = "intervention/open.html"
    intervention = get_object_or_404(Intervention, id=id)
    form = OpenInterventionForm(instance=intervention)
    context = {
        "intervention": intervention,
        "form": form,
    }
    context = BaseContext(request, context).context
    return render(request, template, context)


@login_required
def edit_view(request: HttpRequest, id: str):
    """
    Renders a view for editing interventions

    Args:
        request (HttpRequest): The incoming request

    Returns:

    """
    template = "konova/form.html"
    intervention = get_object_or_404(Intervention, id=id)
    if request.method == "POST":
        form = EditInterventionForm(request.POST or None, instance=intervention)
        if form.is_valid():
            intervention = form.save(request.user)
            messages.success(request, _("{} edited").format(intervention))
            return redirect("intervention:index")
        else:
            messages.error(request, _("Invalid input"))
    form = EditInterventionForm(instance=intervention)
    context = {
        "form": form,
    }
    context = BaseContext(request, context).context
    return render(request, template, context)


@login_required
def remove_view(request: HttpRequest, id: str):
    """ Renders a remove view for this process

    Args:
        request (HttpRequest): The incoming request
        id (str): The uuid id as string

    Returns:

    """
    template = "konova/form.html"
    # Since an intervention is always organized inside a process, we will call the process removing routine, which
    # disables all related elements by default
    obj = get_object_or_404(Intervention, id=id)
    process = obj.process
    if request.method == "POST":
        form = RemoveForm(
            request.POST or None,
            object_to_remove=obj,
            remove_post_url=reverse("process:remove", args=(process.id,)),
            cancel_url=reverse("intervention:index"),
        )
        if form.is_valid():
            confirmed = form.is_checked()
            if confirmed:
                process.deactivate()
                messages.success(request, _("Intervention {} removed").format(obj))
            return redirect("intervention:index")
        else:
            messages.error(request, _("Invalid input"))

    form = RemoveForm(
        object_to_remove=obj,
        remove_post_url=reverse("process:remove", args=(process.id,)),
        cancel_url=reverse("intervention:index"),
    )
    context = {
        "form": form,
    }
    context = BaseContext(request, context).context
    return render(request, template, context)