from .context import context_adaption
from django.conf import settings
from django.shortcuts import render, redirect, HttpResponse
from django.http import HttpResponseNotFound, HttpResponseForbidden
import fstools
import importlib
import mimetypes
from mycreole import url_upload, url_attachment, url_delete
import logging
import mycreole
import os
import stringtools
import themes
from django.contrib import messages

try:
    from config import APP_NAME as ROOT_LOGGER_NAME
except ImportError:
    ROOT_LOGGER_NAME = 'root'
logger = logging.getLogger(ROOT_LOGGER_NAME).getChild(__name__)


def get_method(import_string):
    class_data = import_string.split(".")
    module_path = ".".join(class_data[:-1])
    class_str = class_data[-1]
    #
    module = importlib.import_module(module_path)
    return getattr(module, class_str)


def get_next(request):
    if not request.POST:
        return request.GET.get('next', '/')
    else:
        return request.POST.get('next', '/')


def access(access_type, request, rel_path):
    def log_warning(access_type, e):
        logger.warning('Could not import %s_access method for checking access rights: %s - %s', access_type, type(e).__name__, e)

    try:
        method_name = settings.MYCREOLE_ATTACHMENT_ACCESS[access_type]
    except (AttributeError, KeyError) as e:
        log_warning(access_type, e)
        return False
    else:
        if method_name in [True, None]:
            return True
        elif method_name is False:
            return False
        else:
            try:
                return get_method(method_name)(request, rel_path)
            except AttributeError as e:
                log_warning(access_type, e)
                return False


def mycreole_attachment(request, rel_path):
    full_path = mycreole.get_full_path(rel_path)
    if access('read', request, rel_path):
        if os.path.isfile(full_path):
            mimetypes.init()
            mime_type = mimetypes.types_map.get(os.path.splitext(full_path)[1])
            data = open(full_path, 'rb').read()
            return HttpResponse(data, content_type=mime_type)
        else:
            return HttpResponseNotFound(rel_path)
    else:
        return HttpResponseForbidden(rel_path)


def mycreole_upload(request, rel_path):
    if access('modify', request, rel_path):
        if not request.POST:
            context = themes.Context(request)
            context_adaption(
                context,
                request,
                'Upload %s' % rel_path,
                os.path.dirname(rel_path),
                rel_path_is_directory=os.path.isdir(mycreole.get_full_path(rel_path)),
                next=request.GET.get('next', '/')
            )
            return render(request, 'mycreole/upload.html', context=context)
        else:
            filename = request.POST.get('filename')
            full_path = mycreole.get_full_path(rel_path)
            if filename is not None:
                full_path = os.path.join(full_path, filename)
            try:
                os.makedirs(os.path.dirname(full_path), exist_ok=True)
            except PermissionError:
                raise PermissionError("Ensure that we have access to MYCREOLE_ROOT=%s" % repr(settings.MYCREOLE_ROOT))
            else:
                with open(full_path, 'wb') as fh:
                    fh.write(request.FILES['file'].read())
                messages.info(request, 'File %s successfully uploaded.' % os.path.basename(full_path))
            return redirect(request.POST.get('next', '/'))
    else:
        messages.error(request, "Upload: Access denied!")
        return redirect(request.GET.get('next', '/'))


def mycreole_delete(request, rel_path):
    context = themes.Context(request)      # needs to be executed first because of time mesurement
    nxt = get_next(request)
    modify_access = access('modify', request, rel_path)
    full_path = mycreole.get_full_path(rel_path)
    if not modify_access:
        messages.error(request, 'Detele Attachment: Access denied!')
    else:
        if not request.POST:
            context_adaption(
                context,
                request,
                'Delete %s' % os.path.basename(rel_path),
                os.path.dirname(rel_path),
                next=nxt,
                filename=os.path.basename(rel_path)
            )
            return render(request, 'mycreole/delete.html', context=context)
        else:
            if request.POST.get('yes') is not None:
                try:
                    os.remove(full_path)
                except Exception:
                    messages.error(request, 'Error while deleting file from filesystem.')
                    logger.exception('Fatal error while deleting Attachment!')
                else:
                    messages.info(request, "Attachment %s deleted..." % os.path.basename(full_path))
            else:
                messages.info(request, 'Delete request aborded.')
    return redirect(nxt)


def mycreole_manageuploads(request, rel_path):
    context = themes.Context(request)      # needs to be executed first because of time mesurement
    nxt = get_next(request)
    read_access = access('read', request, rel_path)
    modify_access = access('modify', request, rel_path)
    #
    if not read_access:
        messages.error(request, "Manageupload: Access denied!")
        return redirect(nxt)

    basepath = mycreole.get_full_path(rel_path)
    if not os.path.exists(basepath):
        logger.info('Creating path for attachments: %s', basepath)
        fstools.mkdir(basepath)
    logger.debug("Searching for files in %s", basepath)
    attachments = {}
    for file in fstools.filelist(basepath):
        filename = os.path.basename(file)
        actions = []
        if modify_access:
            actions.append((themes.gray_icon_url(request, 'delete.png'), url_delete(request, os.path.join(rel_path, filename)), 'delete'))
            actions.append((themes.gray_icon_url(request, 'shuffle.png'), url_upload(request, os.path.join(rel_path, filename)), 'replace'))
            actions.append((themes.gray_icon_url(request, 'view.png'), url_attachment(os.path.join(rel_path, filename)), 'view'))
        attachments[filename] = {
            'size': stringtools.physical_value_repr(os.path.getsize(file), 'B'),
            'modify_access': modify_access,
            'actions': actions,
        }
    logger.debug("%d attachments detected: %s", len(attachments), ', '.join(attachments.keys()))
    #
    mycreole.context.context_adaption(
        context,
        request,
        'Manageuploads for %s' % rel_path,
        rel_path,
        next=nxt,
        attachments=attachments
    )
    return render(request, 'mycreole/manageuploads.html', context=context)