from datetime import datetime

from django.contrib.auth.models import User

from django.shortcuts import render_to_response, redirect

from django.http import Http404

from django.contrib.auth.decorators import login_required

from django.core.context_processors import csrf

from django.views.decorators.csrf import csrf_protect

from pytask.utils import make_key

from pytask.views import show_msg

from pytask.taskapp.models import Task, TaskComment, TaskClaim

from pytask.taskapp.forms import CreateTaskForm, EditTaskForm, \

                                 TaskCommentForm, ClaimTaskForm, \

                                 ChoiceForm, EditTaskForm

from pytask.taskapp.utils import getTask

from pytask.profile.utils import get_notification

@login_required

def create_task(request):

    user = request.user

    profile = user.get_profile()

    context = {"user": user,

               "profile": profile,

              }

    context.update(csrf(request))

    can_create_task = False if profile.rights == "CT" else True

    if can_create_task:

        if request.method == "POST":

            form = CreateTaskForm(request.POST)

            if form.is_valid():

                data = form.cleaned_data.copy()

                data.update({"created_by": user,

                             "creation_datetime": datetime.now(),

                             "uniq_key": make_key(Task),

                            })

                task = Task(**data)

                task.save()

                task_url = '/task/view/tid=%s'%task.uniq_key

                return redirect(task_url)

            else:

                context.update({'form':form})

                return render_to_response('task/create.html', context)

        else:

            form = CreateTaskForm()

            context.update({'form':form})

            return render_to_response('task/create.html', context)

    else:

        return show_msg(user, 'You are not authorised to create a task.')

def view_task(request, tid):

    """ get the task depending on its tid and display accordingly if it is a get.

    check for authentication and add a comment if it is a post request.

    """

    task_url = "/task/view/tid=%s"%tid

    task = getTask(tid)

    user = request.user

    if not user.is_authenticated():

        return render_to_response("/task/view.html", {"task": task})

    profile = user.get_profile()

    context = {"user": user,

               "profile": profile,

               "task": task,

              }

    context.update(csrf(request))

    if task.status == "DL":

        return show_msg(user, 'This task no longer exists', '/task/browse/','browse the tasks')

    task_viewable = True if ( task.status != "UP" ) or profile.rights != "CT"\

                         else False

    if not task_viewable:

        return show_msg(user, "You are not authorised to view this task", "/task/browse/", "browse the tasks")

    reviewers = task.reviewers.all()

    is_reviewer = True if user in task.reviewers.all() else False

    comments = task.comments.filter(is_deleted=False).order_by('comment_datetime')

    context.update({'is_reviewer':is_reviewer,

                    'comments':comments,

                    'reviewers':reviewers,

                   })

    claimed_users = task.claimed_users.all()

    selected_users = task.selected_users.all()

    is_creator = True if user == task.created_by else False

    has_claimed = True if user in claimed_users else False

    context['selected_users'] = selected_users

    context['is_selected'] = True if user in selected_users else False

    context['can_approve'] = True if task.status == "UP" and\

                                     profile.rights in ["MG", "DC"]\

                                     else False

    context['can_edit'] = True if is_creator and task.status == "UP" else False

    context['can_close'] = True if task.status not in ["UP", "CD", "CM"] and is_reviewer else False

    context['can_delete'] = True if task.status == "UP" and is_creator else False

    context['can_assign_pynts'] = True if task.status in ["OP", "WR"] and is_reviewer else False

    context['task_claimable'] = True if task.status in ["OP", "WR"] else False

    context['can_comment'] = True if task.status != "UP" or\

                                     profile.rights!="CT" else False

#    if task.status == "CD":

#        context['closing_notification'] =  Notification.objects.filter(task=task,role="CD")[0]

#    elif task.status == "CM":

#        context['completed_notification'] =  Notifications.objects.filter(task=task,role="CM")[0]

#    elif task.status == "WR":

#        context['assigned_users'] = task.assigned_users.all()

    if request.method == 'POST':

        form = TaskCommentForm(request.POST)

        if form.is_valid():

            data = form.cleaned_data['data']

            new_comment = TaskComment(task=task, data=data,

                                      uniq_key=make_key(TaskComment),

                                      commented_by=user, comment_datetime=datetime.now())

            new_comment.save()

            return redirect(task_url)

        else:

            context['form'] = form

            return render_to_response('task/view.html', context)

    else:

        form = TaskCommentForm()

        context['form'] = form

        return render_to_response('task/view.html', context)

@login_required

def edit_task(request, tid):

    """ only creator gets to edit the task and that too only before it gets

    approved.

    """

    user = request.user

    profile = user.get_profile()

    task_url = "/task/view/tid=%s"%tid

    task = getTask(tid)

    is_creator = True if user == task.created_by else False

    can_edit = True if task.status == "UP" and is_creator else False

    if not can_edit:

        raise Http404

    context = {"user": user,

               "profile": profile,

               "task": task,

              }

    context.update(csrf(request))

    if request.method == "POST":

        form = EditTaskForm(request.POST, instance=task)

        if form.is_valid():

            form.save()

            return redirect(task_url)

        else:

            context.update({"form": form})

            return render_to_response("task/edit.html", context)

    else:

        form = EditTaskForm(instance=task)

        context.update({"form": form})

        return render_to_response("task/edit.html", context)

@login_required

def claim_task(request, tid):

    task_url = "/task/view/tid=%s"%tid

    claim_url = "/task/claim/tid=%s"%tid

    task = getTask(tid)

    if task.status == "UP":

        raise Http404

    user = request.user

    profile = user.get_profile()

    context = {"user": user,

               "profile": profile,

               "task": task,

              }

    context.update(csrf(request))

    reviewers = task.reviewers.all()

    claimed_users = task.claimed_users.all()

    selected_users = task.selected_users.all()

    is_creator = True if user == task.created_by else False

    is_reviewer = True if user in reviewers else False

    has_claimed = True if user in claimed_users else False

    task_claimable = True if task.status in ["OP", "WR"] else False

    can_claim = True if task_claimable and ( not has_claimed )\

                        and ( not is_reviewer ) and (not is_creator ) \

                        else False

    old_claims = task.claims.all()

    context.update({"is_creator": is_creator,

                    "task_claimable": task_claimable,

                    "can_claim": can_claim,

                    "old_claims": old_claims})

    if request.method == "POST" and can_claim:

        form = ClaimTaskForm(request.POST)

        if form.is_valid():

            data = form.cleaned_data.copy()

            data.update({"uniq_key": make_key(TaskClaim),

                         "task": task,

                         "claim_datetime": datetime.now(),

                         "claimed_by": user,})

            new_claim = TaskClaim(**data)

            new_claim.save()

            task.claimed_users.add(user)

            task.save()

            return redirect(claim_url)

        else:

            context.update({"form": form})

            return render_to_response("task/claim.html", context)

    else:

        form = ClaimTaskForm()

        context.update({"form": form})

        return render_to_response("task/claim.html", context)

@login_required

def select_user(request, tid):

    """ first get the status of the task and then select one of claimed users

    generate list of claimed users by passing it as an argument to a function.

    """

    task_url = "/task/view/tid=%s"%tid

    user = request.user

    profile = user.get_profile()

    task = getTask(tid)

    context = {"user": user,

               "profile": profile,

               "task": task,

              }

    context.update(csrf(request))

    claimed_users = task.claimed_users.all()

    selected_users = task.selected_users.all()

    task_claimed = True if claimed_users else False

    is_creator = True if user == task.created_by else False

    if ( is_creator or profile.rights in ["CR", "DC"] ) and \

       task.status in ["OP", "WR"]:

        if task_claimed:

            user_list = ((user.id,user.username) for user in claimed_users)

            if request.method == "POST":

                form = ChoiceForm(user_list, request.POST)

                if form.is_valid():

                    uid = form.cleaned_data['choice']

                    selected_user = User.objects.get(id=uid)

                    task.selected_users.add(selected_user)

                    task.claimed_users.remove(selected_user)

                    task.status = "WR"

                    task.save()

                    return redirect(task_url)

                else:

                    context.update({"form": form})

                    return render_to_response('task/select_user.html', context)

            else:

                form = ChoiceForm(user_list)

                context.update({"form": form})

                return render_to_response('task/select_user.html', context)

        else:

            return show_msg(user, 'There are no pending claims for this task',

                            task_url, 'view the task')

    else:

        raise Http404