;;; magit-repos.el --- listing repositories  -*- lexical-binding: t -*-

;; Copyright (C) 2010-2017  The Magit Project Contributors
;;
;; You should have received a copy of the AUTHORS.md file which
;; lists all contributors.  If not, see http://magit.vc/authors.

;; Author: Jonas Bernoulli <jonas@bernoul.li>
;; Maintainer: Jonas Bernoulli <jonas@bernoul.li>

;; Magit 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, or (at your option)
;; any later version.
;;
;; Magit 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 Magit.  If not, see http://www.gnu.org/licenses.

;;; Commentary:

;; This library implements support for listing repositories.  This
;; includes getting a Lisp list of known repositories as well as a
;; mode for listing repositories in a buffer.

;;; Code:

(require 'magit-core)

(declare-function magit-status-internal 'magit-status)

(defvar x-stretch-cursor)

;;; Options

(defcustom magit-repository-directories nil
  "List of directories that are or contain Git repositories.

Each element has the form (DIRECTORY . DEPTH) or, for backward
compatibility, just DIRECTORY.  DIRECTORY has to be a directory
or a directory file-name, a string.  DEPTH, an integer, specifies
the maximum depth to look for Git repositories.  If it is 0, then
only add DIRECTORY itself.

For backward compatibility reasons an element may be a string,
instead of a cons-cell, in which case the value of the obsolete
option `magit-repository-directories-depth' specifies the depth."
  :package-version '(magit . "2.8.0")
  :group 'magit-essentials
  :type '(repeat (choice (cons directory (integer :tag "Depth")) directory)))

(defvar magit-repository-directories-depth 3
  "The maximum depth to look for Git repositories.
This variable is obsolete and only used for elements of the
option `magit-repository-directories' (which see) that don't
specify the depth directly.")

(defgroup magit-repolist nil
  "List repositories in a buffer."
  :link '(info-link "(magit)Repository List")
  :group 'magit-modes)

(defcustom magit-repolist-mode-hook '(hl-line-mode)
  "Hook run after entering Magit-Repolist mode."
  :package-version '(magit . "2.9.0")
  :group 'magit-repolist
  :type 'hook
  :get 'magit-hook-custom-get
  :options '(hl-line-mode))

(defcustom magit-repolist-columns
  '(("Name"    25 magit-repolist-column-ident                  nil)
    ("Version" 25 magit-repolist-column-version                nil)
    ("B<U"      3 magit-repolist-column-unpulled-from-upstream ((:right-align t)))
    ("B>U"      3 magit-repolist-column-unpushed-to-upstream   ((:right-align t)))
    ("Path"    99 magit-repolist-column-path                   nil))
  "List of columns displayed by `magit-list-repositories'.

Each element has the form (HEADER WIDTH FORMAT PROPS).

HEADER is the string displayed in the header.  WIDTH is the width
of the column.  FORMAT is a function that is called with one
argument, the repository identification (usually its basename),
and with `default-directory' bound to the toplevel of its working
tree.  It has to return a string to be inserted or nil.  PROPS is
an alist that supports the keys `:right-align' and `:pad-right'."
  :package-version '(magit . "2.8.0")
  :group 'magit-repolist
  :type `(repeat (list :tag "Column"
                       (string   :tag "Header Label")
                       (integer  :tag "Column Width")
                       (function :tag "Inserter Function")
                       (repeat   :tag "Properties"
                                 (list (choice :tag "Property"
                                               (const :right-align)
                                               (const :pad-right)
                                               (symbol))
                                       (sexp   :tag "Value"))))))


;;; List Repositories
;;;; Command
;;;###autoload
(defun magit-list-repositories ()
  "Display a list of repositories.

Use the options `magit-repository-directories'
and `magit-repository-directories-depth' to
control which repositories are displayed."
  (interactive)
  (if magit-repository-directories
      (with-current-buffer (get-buffer-create "*Magit Repositories*")
        (magit-repolist-mode)
        (setq tabulated-list-entries
              (mapcar (-lambda ((id . path))
                        (let ((default-directory path))
                          (list path
                                (vconcat (--map (or (funcall (nth 2 it) id) "")
                                                magit-repolist-columns)))))
                      (magit-list-repos-uniquify
                       (--map (cons (file-name-nondirectory (directory-file-name it))
                                    it)
                              (magit-list-repos)))))
        (tabulated-list-print)
        (switch-to-buffer (current-buffer)))
    (message "You need to customize `magit-repository-directories' %s"
             "before you can list repositories")))

;;;; Mode

(defvar magit-repolist-mode-map
  (let ((map (make-sparse-keymap)))
    (set-keymap-parent map tabulated-list-mode-map)
    (define-key map "g" 'magit-list-repositories)
    (define-key map (if (featurep 'jkl) [return] (kbd "C-m"))
      'magit-repolist-status)
    map)
  "Local keymap for Magit-Repolist mode buffers.")

(defun magit-repolist-status (&optional _button)
  "Show the status for the repository at point."
  (interactive)
  (--if-let (tabulated-list-get-id)
      (magit-status-internal (expand-file-name it))
    (user-error "There is no repository at point")))

(define-derived-mode magit-repolist-mode tabulated-list-mode "Repos"
  "Major mode for browsing a list of Git repositories."
  (setq x-stretch-cursor        nil)
  (setq tabulated-list-padding  0)
  (setq tabulated-list-sort-key (cons "Name" nil))
  (setq tabulated-list-format
        (vconcat (mapcar (-lambda ((title width _fn props))
                           (nconc (list title width t)
                                  (-flatten props)))
                         magit-repolist-columns)))
  (tabulated-list-init-header)
  (setq imenu-prev-index-position-function
        'magit-imenu--repolist-prev-index-position-function)
  (setq imenu-extract-index-name-function
        'magit-imenu--repolist-extract-index-name-function))

;;;; Columns

(defun magit-repolist-column-ident (id)
  "Insert the identification of the repository.
Usually this is just its basename."
  id)

(defun magit-repolist-column-path (_id)
  "Insert the absolute path of the repository."
  (abbreviate-file-name default-directory))

(defun magit-repolist-column-version (_id)
  "Insert a description of the repository's `HEAD' revision."
  (let ((v (or (magit-git-string "describe" "--tags")
               ;; If there are no tags, use the date in MELPA format.
               (magit-git-string "show" "--no-patch" "--format=%cd-g%h"
                                 "--date=format:%Y%m%d.%H%M"))))
    (if (and v (string-match-p "\\`[0-9]" v))
        (concat " " v)
      v)))

(defun magit-repolist-column-branch (_id)
  "Insert the current branch."
  (magit-get-current-branch))

(defun magit-repolist-column-upstream (_id)
  "Insert the upstream branch of the current branch."
  (magit-get-upstream-branch))

(defun magit-repolist-column-dirty (_id)
  "Insert a letter if there are uncommitted changes.

Show N if there is at least one untracked file.
Show U if there is at least one unstaged file.
Show S if there is at least one staged file.
Only one letter is shown, the first that applies."
  (cond ((magit-untracked-files) "N")
        ((magit-unstaged-files)  "U")
        ((magit-staged-files)    "S")))

(defun magit-repolist-column-unpulled-from-upstream (_id)
  "Insert number of upstream commits not in the current branch."
  (--when-let (magit-get-upstream-branch nil t)
    (let ((n (cadr (magit-rev-diff-count "HEAD" it))))
      (propertize (number-to-string n) 'face (if (> n 0) 'bold 'shadow)))))

(defun magit-repolist-column-unpulled-from-pushremote (_id)
  "Insert number of commits in the push branch but not the current branch."
  (--when-let (magit-get-push-branch nil t)
    (let ((n (cadr (magit-rev-diff-count "HEAD" it))))
      (propertize (number-to-string n) 'face (if (> n 0) 'bold 'shadow)))))

(defun magit-repolist-column-unpushed-to-upstream (_id)
  "Insert number of commits in the current branch but not its upstream."
  (--when-let (magit-get-upstream-branch nil t)
    (let ((n (car (magit-rev-diff-count "HEAD" it))))
      (propertize (number-to-string n) 'face (if (> n 0) 'bold 'shadow)))))

(defun magit-repolist-column-unpushed-to-pushremote (_id)
  "Insert number of commits in the current branch but not its push branch."
  (--when-let (magit-get-push-branch nil t)
    (let ((n (car (magit-rev-diff-count "HEAD" it))))
      (propertize (number-to-string n) 'face (if (> n 0) 'bold 'shadow)))))

(defun magit-repolist-column-branches (_id)
  "Insert number of branches."
  (let ((n (length (magit-list-local-branches))))
    (propertize (number-to-string n) 'face (if (> n 1) 'bold 'shadow))))

(defun magit-repolist-column-stashes (_id)
  "Insert number of stashes."
  (let ((n (length (magit-list-stashes))))
    (propertize (number-to-string n) 'face (if (> n 0) 'bold 'shadow))))

;;; Read Repository

(defun magit-read-repository (&optional read-directory-name)
  "Read a Git repository in the minibuffer, with completion.

The completion choices are the basenames of top-levels of
repositories found in the directories specified by option
`magit-repository-directories'.  In case of name conflicts
the basenames are prefixed with the name of the respective
parent directories.  The returned value is the actual path
to the selected repository.

With prefix argument simply read a directory name using
`read-directory-name'."
  (if (and (not read-directory-name) magit-repository-directories)
      (let* ((repos (magit-list-repos-uniquify
                     (--map (cons (file-name-nondirectory
                                   (directory-file-name it))
                                  it)
                            (magit-list-repos))))
             (reply (magit-completing-read "Git repository" repos)))
        (file-name-as-directory
         (or (cdr (assoc reply repos))
             (if (file-directory-p reply)
                 (expand-file-name reply)
               (user-error "Not a repository or a directory: %s" reply)))))
    (file-name-as-directory
     (read-directory-name "Git repository: "
                          (or (magit-toplevel) default-directory)))))

(defun magit-list-repos ()
  (--mapcat (if (consp it)
                (magit-list-repos-1 (car it) (cdr it))
              (magit-list-repos-1 it magit-repository-directories-depth))
            magit-repository-directories))

(defun magit-list-repos-1 (directory depth)
  (cond ((file-readable-p (expand-file-name ".git" directory))
         (list directory))
        ((and (> depth 0) (magit-file-accessible-directory-p directory))
         (--mapcat (and (file-directory-p it)
                        (magit-list-repos-1 it (1- depth)))
                   (directory-files directory t
                                    directory-files-no-dot-files-regexp t)))))

(defun magit-list-repos-uniquify (alist)
  (let (result (dict (make-hash-table :test 'equal)))
    (dolist (a (delete-dups alist))
      (puthash (car a) (cons (cdr a) (gethash (car a) dict)) dict))
    (maphash
     (lambda (key value)
       (if (= (length value) 1)
           (push (cons key (car value)) result)
         (setq result
               (append result
                       (magit-list-repos-uniquify
                        (--map (cons (concat
                                      key "\\"
                                      (file-name-nondirectory
                                       (directory-file-name
                                        (substring it 0 (- (1+ (length key)))))))
                                     it)
                               value))))))
     dict)
    result))

(provide 'magit-repos)
;;; magit-repos.el ends here
