;;; oni-python.el --- Extra Python commands          -*- lexical-binding: t; -*-

;; Copyright (C) 2015  Tom Willemse

;; Author: Tom Willemse <tom@ryuslash.org>
;; Keywords:

;; This program is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.

;; This program is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with this program.  If not, see <http://www.gnu.org/licenses/>.

;;; Commentary:

;; Here are some extra Emacs commands for working with Python source
;; code.

;;; Code:

(require 'auto-complete)
(require 'fill-column-indicator)
(require 'python)
(require 'whitespace)

;;;###autoload
(defun oni:add-import-from (package import)
  "Add a Python import statement at the beginning of the module."
  (interactive
   (list (completing-read "From package: " (oni:collect-from-imports))
         (read-string "Import: ")))
  (save-excursion
    (goto-char (point-min))
    (search-forward (concat "from " package " import ("))
    (insert "\n    " import ",")
    (oni:sort-imports)))

(defun oni:collect-from-imports ()
  "Find all modules from which names are imported in the current file."
  (let (results)
    (save-excursion
      (goto-char (point-min))
      (while (re-search-forward "from \\(.+\\) import" nil :noerror)
        (push (buffer-substring-no-properties (match-beginning 1)
                                              (match-end 1)) results)))
    results))

;;;###autoload
(defun oni:clear-electric-indent-chars ()
  "Clear the `electric-indent-chars' which don't work well in Python."
  (set (make-local-variable 'electric-indent-chars) nil))

;;;###autoload
(defun oni:make-import-multiline (from-point to-point)
  "Turn an import statement into a multi-line import statement."
  (interactive (list (line-beginning-position)
                     (line-end-position)))
  (goto-char from-point)
  (search-forward "import" to-point)
  (insert " (\n")
  (delete-horizontal-space)
  (let ((imports-start (point)) imports-end)
    (while (search-forward "," to-point :noeror)
      (insert "\n")
      (delete-horizontal-space))
    (end-of-line)
    (insert ",\n")
    (setf imports-end (point))
    (insert ")")
    (python-indent-shift-right imports-start imports-end)
    (forward-line -1)
    (oni:sort-imports)))

;;;###autoload
(defun oni:set-keys-for-python ()
  "Set Python mode-specific keybindings."
  (define-key python-mode-map (kbd "C->") #'python-indent-shift-right)
  (define-key python-mode-map (kbd "C-<") #'python-indent-shift-left))

;;;###autoload
(defun oni:set-pep8-fill-column ()
  "Set the `fill-column' to the PEP 8 recommendation."
  (setq-local fill-column 72))

;;;###autoload
(defun oni:set-pep8-margin ()
  "Set the `fci-rule-column' the the PEP 8 recommendation."
  (setq-local fci-rule-column 79))

;;;###autoload
(defun oni:set-python-completion-sources ()
  "Set `ac-sources' to python-specific sources."
  (setq ac-sources '(ac-source-jedi-direct)))

;;;###autoload
(defun oni:set-python-imenu-function ()
  "Set the `imenu-create-index-function' variable.

For `python-mode' I prefer `python-imenu-create-flat-index'."
  (setq imenu-create-index-function #'python-imenu-create-flat-index))

;;;###autoload
(defun oni:set-python-symbols ()
  "Set a few extra UTF-8 symbols for use in python."
  (when (boundp 'prettify-symbols-alist)
    (setq prettify-symbols-alist
          '(("lambda" . ?λ)
            ("<=" . ?≤)
            (">=" . ?≥)
            ("!=" . ?≠)))))

;;;###autoload
(defun oni:set-whitespace-tab-display ()
  "Set the `whitespace-style' to show only tabs."
  (setq-local whitespace-style '(tab-mark)))

;;;###autoload
(defun oni:sort-imports ()
  "Sort python multiline imports using `()'."
  (interactive)
  (save-excursion
    (sort-lines nil (1+ (search-backward "("))
                (1- (search-forward ")")))))

;;; Tests

(ert-deftest oni:add-import-from ()
  (with-temp-buffer
    (python-mode)
    (insert "from myaethon2.core.administration.models import (
    Client,
    Contact,
    Individual,
    Location,
)")
    (oni:add-import-from "myaethon2.core.administration.models" "Debtor")
    (should (equal (buffer-substring-no-properties (point-min) (point-max))
                   "from myaethon2.core.administration.models import (
    Client,
    Contact,
    Debtor,
    Individual,
    Location,
)"))))

(ert-deftest oni:collect-from-imports ()
  (with-temp-buffer
    (python-mode)
    (insert "import calendar as cal
import datetime

from django.conf import settings
from django.contrib import messages
from django.contrib.auth.decorators import login_required, permission_required
from django.core.context_processors import csrf
from django.core.exceptions import PermissionDenied
from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger
from django.core.urlresolvers import reverse
from django.db import transaction
from django.db.models import Q
from django.shortcuts import get_object_or_404, render
from django.utils import formats
from django.utils.translation import ugettext as _

from myaethon2.core.business_units import BU
from myaethon2.core.forms import MultiFormWrapper
from myaethon2.core.models import AUser, Service
from myaethon2.core.planning.models import Booking, JOB_TYPES
from myaethon2.core.util import simplify_timedelta
from myaethon2.core.views import SearchAndSortListView
from myaethon2.jobs import forms, status
from myaethon2.jobs.models import Assignment, Job, JobGroup
from myaethon2.jobs.util import JobFactory
from myaethon2.workers.models import Worker
from myaethon2.export import Exporter, XLSGenerator

from django.http import (
    HttpResponseForbidden,
    HttpResponseNotAllowed,
    HttpResponseRedirect,
)

from django.views.generic import (
    CreateView,
    DeleteView,
    DetailView,
    ListView,
    UpdateView,
)

from myaethon2.core.administration.models import (
    Client,
    Contact,
    Debtor,
    Individual,
    Location,
)

from myaethon2.core.decorators import (
    json_response,
    protect_with,
    with_help_text,
)")
    (should (equal (sort (oni:collect-from-imports) #'string-lessp)
                   '("django.conf"
                     "django.contrib"
                     "django.contrib.auth.decorators"
                     "django.core.context_processors"
                     "django.core.exceptions"
                     "django.core.paginator"
                     "django.core.urlresolvers"
                     "django.db"
                     "django.db.models"
                     "django.http"
                     "django.shortcuts"
                     "django.utils"
                     "django.utils.translation"
                     "django.views.generic"
                     "myaethon2.core.administration.models"
                     "myaethon2.core.business_units"
                     "myaethon2.core.decorators"
                     "myaethon2.core.forms"
                     "myaethon2.core.models"
                     "myaethon2.core.planning.models"
                     "myaethon2.core.util"
                     "myaethon2.core.views"
                     "myaethon2.export"
                     "myaethon2.jobs"
                     "myaethon2.jobs.models"
                     "myaethon2.jobs.util"
                     "myaethon2.workers.models")))))

(ert-deftest oni:make-import-multiline ()
  (with-temp-buffer
    (python-mode)
    (insert "from myaethon2.core.administration.models import Contact, Individual, Client, Location")
    (oni:make-import-multiline (line-beginning-position) (line-end-position))
    (should (equal (buffer-substring-no-properties (point-min) (point-max))
                   "from myaethon2.core.administration.models import (
    Client,
    Contact,
    Individual,
    Location,
)"))))

(provide 'oni-python)
;;; oni-python.el ends here