# Patchwork - automated patch tracking system
# Copyright (C) 2008 Jeremy Kerr <jk@ozlabs.org>
#
# SPDX-License-Identifier: GPL-2.0-or-later

from django.contrib import messages
from django.shortcuts import get_object_or_404
from django.db.models import Prefetch

from patchwork.filters import Filters
from patchwork.forms import MultiplePatchForm
from patchwork.models import Bundle
from patchwork.models import BundlePatch
from patchwork.models import Patch
from patchwork.models import Project
from patchwork.models import Check
from patchwork.paginator import Paginator


bundle_actions = ['create', 'add', 'remove']


def get_patch_ids(d, prefix='patch_id'):
    ids = []

    for (k, v) in d.items():
        a = k.split(':')
        if len(a) != 2:
            continue
        if a[0] != prefix:
            continue
        if not v:
            continue
        ids.append(a[1])

    return ids


class Order(object):
    order_map = {
        'date': 'date',
        'name': 'name',
        'state': 'state__ordering',
        'submitter': 'submitter__name',
        'delegate': 'delegate__username',
    }
    default_order = ('date', True)

    def __init__(self, str=None, editable=False):
        self.reversed = False
        self.editable = editable
        (self.order, self.reversed) = self.default_order

        if self.editable:
            return

        if str is None or str == '':
            return

        reversed = False
        if str[0] == '-':
            str = str[1:]
            reversed = True

        if str not in self.order_map:
            return

        self.order = str
        self.reversed = reversed

    def __str__(self):
        str = self.order
        if self.reversed:
            str = '-' + str
        return str

    def name(self):
        return self.order

    def reversed_name(self):
        if self.reversed:
            return self.order
        else:
            return '-' + self.order

    def updown(self):
        if self.reversed:
            return 'up'
        return 'down'

    def apply(self, qs):
        q = self.order_map[self.order]
        if self.reversed:
            q = '-' + q

        orders = [q]

        # if we're using a non-default order, add the default as a secondary
        # ordering. We reverse the default if the primary is reversed.
        (default_name, default_reverse) = self.default_order
        if self.order != default_name:
            q = self.order_map[default_name]
            if self.reversed ^ default_reverse:
                q = '-' + q
            orders.append(q)

        return qs.order_by(*orders)


# TODO(stephenfin): Refactor this to break it into multiple, testable functions
def set_bundle(request, project, action, data, patches, context):
    # set up the bundle
    bundle = None
    user = request.user

    if action == 'create':
        bundle_name = data['bundle_name'].strip()
        if '/' in bundle_name:
            return ['Bundle names can\'t contain slashes']

        if not bundle_name:
            return ['No bundle name was specified']

        if Bundle.objects.filter(owner=user, name=bundle_name).count() > 0:
            return ['You already have a bundle called "%s"' % bundle_name]

        bundle = Bundle(owner=user, project=project,
                        name=bundle_name)
        bundle.save()
        messages.success(request, "Bundle %s created" % bundle.name)
    elif action == 'add':
        bundle = get_object_or_404(Bundle, id=data['bundle_id'])
    elif action == 'remove':
        bundle = get_object_or_404(Bundle, id=data['removed_bundle_id'])

    if not bundle:
        return ['no such bundle']

    for patch in patches:
        if action in ['create', 'add']:
            bundlepatch_count = BundlePatch.objects.filter(bundle=bundle,
                                                           patch=patch).count()
            if bundlepatch_count == 0:
                bundle.append_patch(patch)
                messages.success(request, "Patch '%s' added to bundle %s" %
                                 (patch.name, bundle.name))
            else:
                messages.warning(request, "Patch '%s' already in bundle %s" %
                                 (patch.name, bundle.name))
        elif action == 'remove':
            try:
                bp = BundlePatch.objects.get(bundle=bundle, patch=patch)
                bp.delete()
            except BundlePatch.DoesNotExist:
                pass
            else:
                messages.success(
                    request,
                    "Patch '%s' removed from bundle %s\n" % (patch.name,
                                                             bundle.name))

    bundle.save()

    return []


def generic_list(request, project, view, view_args=None, filter_settings=None,
                 patches=None, editable_order=False):

    if not filter_settings:
        filter_settings = []

    filters = Filters(request)
    context = {
        'project': project,
        'projects': Project.objects.all(),
        'filters': filters,
    }

    # pagination

    params = filters.params
    for param in ['order', 'page']:
        data = {}
        if request.method == 'GET':
            data = request.GET
        elif request.method == 'POST':
            data = request.POST

        value = data.get(param, None)
        if value:
            params['param'] = value

    data = {}
    if request.method == 'GET':
        data = request.GET
    elif request.method == 'POST':
        data = request.POST
    order = Order(data.get('order'), editable=editable_order)

    context.update({
        'order': order,
        'list_view': {
            'view': view,
            'view_params': view_args or {},
            'params': params
        }})

    # form processing

    # Explicitly set data to None because request.POST will be an empty dict
    # when the form is not submitted, but passing a non-None data argument to
    # a forms.Form will make it bound and we don't want that to happen unless
    # there's been a form submission.
    if request.method != 'POST':
        data = None
    user = request.user
    properties_form = None

    if user.is_authenticated:
        # we only pass the post data to the MultiplePatchForm if that was
        # the actual form submitted
        data_tmp = None
        if data and data.get('form', '') == 'patchlistform':
            data_tmp = data

        properties_form = MultiplePatchForm(project, data=data_tmp)

    if request.method == 'POST' and data.get('form') == 'patchlistform':
        action = data.get('action', '').lower()

        # special case: the user may have hit enter in the 'create bundle'
        # text field, so if non-empty, assume the create action:
        if data.get('bundle_name', False):
            action = 'create'

        ps = Patch.objects.filter(id__in=get_patch_ids(data))

        if action in bundle_actions:
            errors = set_bundle(request, project, action, data, ps, context)

        elif properties_form and action == properties_form.action:
            errors = process_multiplepatch_form(request, properties_form,
                                                action, ps, context)
        else:
            errors = []

        if errors:
            context['errors'] = errors

    for (filterclass, setting) in filter_settings:
        if isinstance(setting, dict):
            context['filters'].set_status(filterclass, **setting)
        elif isinstance(setting, list):
            context['filters'].set_status(filterclass, *setting)
        else:
            context['filters'].set_status(filterclass, setting)

    if patches is None:
        patches = Patch.objects.filter(patch_project=project)

    # annotate with tag counts
    patches = patches.with_tag_counts(project)

    patches = context['filters'].apply(patches)
    if not editable_order:
        patches = order.apply(patches)

    # we don't need the content, diff or headers for a list; they're text
    # fields that can potentially contain a lot of data
    patches = patches.defer('content', 'diff', 'headers')

    # but we will need to follow the state and submitter relations for
    # rendering the list template
    patches = patches.select_related('state', 'submitter', 'delegate',
                                     'series')

    patches = patches.only('state', 'submitter', 'delegate', 'project',
                           'series__name', 'name', 'date', 'msgid')

    # we also need checks and series
    patches = patches.prefetch_related(
        Prefetch('check_set', queryset=Check.objects.only(
            'context', 'user_id', 'patch_id', 'state', 'date')))

    paginator = Paginator(request, patches)

    context.update({
        'page': paginator.current_page,
        'patchform': properties_form,
        'project': project,
        'order': order,
    })

    return context


def process_multiplepatch_form(request, form, action, patches, context):
    errors = []

    if not form.is_valid() or action != form.action:
        return ['The submitted form data was invalid']

    if len(patches) == 0:
        messages.warning(request, 'No patches selected; nothing updated')
        return errors

    changed_patches = 0
    for patch in patches:
        if not patch.is_editable(request.user):
            errors.append("You don't have permissions to edit patch '%s'"
                          % patch.name)
            continue

        changed_patches += 1
        form.save(patch)

    if changed_patches == 1:
        messages.success(request, '1 patch updated')
    elif changed_patches > 1:
        messages.success(request, '%d patches updated' % changed_patches)
    else:
        messages.warning(request, 'No patches updated')

    return errors