Improve attachment link export functionality

Make attachment links export just as file links.

* lisp/ox-ascii.el
* lisp/ox-html.el
* lisp/ox-latex.el
* lisp/ox-man.el
* lisp/ox-md.el
* lisp/ox-texinfo.el
* lisp/org-attach.el: Move export functionality for attachment links
  into the respective export backend, for feature parity with file
  links.

8 files changed, 116 insertions, 48 deletions

diff --git a/lisp/org-attach.el b/lisp/org-attach.el
index 7dcbbf0..c2ef928 100644
--- a/lisp/org-attach.el
+++ b/lisp/org-attach.el
@@ -637,7 +637,6 @@ Basically, this adds the path to the attachment directory."
 
 (org-link-set-parameters "attachment"
                          :follow #'org-attach-open-link
-                         :export #'org-attach-export-link
                          :complete #'org-attach-complete-link)
 
 (defun org-attach-open-link (link &optional in-emacs)
@@ -678,26 +677,6 @@ and to use an external application to visit the file."
 	   (t (concat "attachment:" file))))
       (error "No attachment directory exist"))))
 
-(defun org-attach-export-link (link description format)
-  "Translate attachment LINK from Org mode format to exported FORMAT.
-Also includes the DESCRIPTION of the link in the export."
-  (save-excursion
-    (let (path desc)
-      (cond
-       ((string-match "::\\([0-9]+\\)\\'" link)
-        (setq link (substring link 0 (match-beginning 0))))
-       ((string-match "::\\(.+\\)\\'" link)
-        (setq link (substring link 0 (match-beginning 0)))))
-      (setq path (file-relative-name (org-attach-expand link))
-            desc (or description link))
-      (pcase format
-        (`html (format "<a target=\"_blank\" href=\"%s\">%s</a>" path desc))
-        (`latex (format "\\href{%s}{%s}" path desc))
-        (`texinfo (format "@uref{%s,%s}" path desc))
-        (`ascii (format "%s (%s)" desc path))
-        (`md (format "[%s](%s)" desc path))
-        (_ path)))))
-
 (defun org-attach-archive-delete-maybe ()
   "Maybe delete subtree attachments when archiving.
 This function is called by `org-archive-hook'.  The option
diff --git a/lisp/ox-ascii.el b/lisp/ox-ascii.el
index 972b58a..bcd62e9 100644
--- a/lisp/ox-ascii.el
+++ b/lisp/ox-ascii.el
@@ -31,7 +31,10 @@
 (require 'ox-publish)
 (require 'cl-lib)
 
+;;; Function Declarations
+
 (declare-function aa2u "ext:ascii-art-to-unicode" ())
+(declare-function org-attach-expand "org-attach" (file))
 
 ;;; Define Back-End
 ;;
@@ -1567,13 +1570,24 @@ CONTENTS is nil.  INFO is a plist holding contextual
 
 DESC is the description part of the link, or the empty string.
 INFO is a plist holding contextual information."
-  (let ((type (org-element-property :type link)))
+  (let* ((raw-type (org-element-property :type link))
+	 (type (if (string= raw-type "attachment")
+		   ;; Attachments are simplified representations of
+		   ;; file links.  When exporting, expose attachments
+		   ;; as if they were file links.
+		   "file"
+		 raw-type))
+	 (raw-path (org-element-property :path link))
+	 (path (cond
+		((string= raw-type "attachment")
+		 (setq raw-path (file-relative-name (org-attach-expand raw-path)))
+		 (concat type ":" raw-path))
+		(t (concat type ":" raw-path)))))
     (cond
      ((org-export-custom-protocol-maybe link desc 'ascii))
      ((string= type "coderef")
-      (let ((ref (org-element-property :path link)))
-	(format (org-export-get-coderef-format ref desc)
-		(org-export-resolve-coderef ref info))))
+      (format (org-export-get-coderef-format path desc)
+	      (org-export-resolve-coderef path info)))
      ;; Do not apply a special syntax on radio links.  Though, use
      ;; transcoded target's contents as output.
      ((string= type "radio") desc)
@@ -1605,13 +1619,10 @@ INFO is a plist holding contextual information."
 	  ;; Don't know what to do.  Signal it.
 	  (_ "???"))))
      (t
-      (let ((raw-link (concat (org-element-property :type link)
-			      ":"
-			      (org-element-property :path link))))
-	(if (not (org-string-nw-p desc)) (format "<%s>" raw-link)
-	  (concat (format "[%s]" desc)
-		  (and (not (plist-get info :ascii-links-to-notes))
-		       (format " (<%s>)" raw-link)))))))))
+      (if (not (org-string-nw-p desc)) (format "<%s>" path)
+	(concat (format "[%s]" desc)
+		(and (not (plist-get info :ascii-links-to-notes))
+		     (format " (<%s>)" path))))))))
 
 
 ;;;; Node Properties
diff --git a/lisp/ox-html.el b/lisp/ox-html.el
index 5c22ea7..6fc4c60 100644
--- a/lisp/ox-html.el
+++ b/lisp/ox-html.el
@@ -42,6 +42,7 @@
 (declare-function org-id-find-id-file "org-id" (id))
 (declare-function htmlize-region "ext:htmlize" (beg end))
 (declare-function mm-url-decode-entities "mm-url" ())
+(declare-function org-attach-expand "org-attach" (file))
 
 (defvar htmlize-css-name-prefix)
 (defvar htmlize-output-type)
@@ -884,10 +885,9 @@ link to the image."
   :type 'boolean)
 
 (defcustom org-html-inline-image-rules
-  '(("file" . "\\.\\(jpeg\\|jpg\\|png\\|gif\\|svg\\)\\'")
-    ("attachment" . "\\.\\(jpeg\\|jpg\\|png\\|gif\\|svg\\)\\'")
-    ("http" . "\\.\\(jpeg\\|jpg\\|png\\|gif\\|svg\\)\\'")
-    ("https" . "\\.\\(jpeg\\|jpg\\|png\\|gif\\|svg\\)\\'"))
+  `(("file" . ,(regexp-opt '(".jpeg" ".jpg" ".png" ".gif" ".svg")))
+    ("http" . ,(regexp-opt '(".jpeg" ".jpg" ".png" ".gif" ".svg")))
+    ("https" . ,(regexp-opt '(".jpeg" ".jpg" ".png" ".gif" ".svg"))))
   "Rules characterizing image files that can be inlined into HTML.
 A rule consists in an association whose key is the type of link
 to consider, and value is a regexp that will be matched against
@@ -3064,7 +3064,13 @@ INFO is a plist holding contextual information.  See
 	      (concat (file-name-sans-extension raw-path) "."
 		      (plist-get info :html-extension)))
 	     (t raw-path))))
-	 (type (org-element-property :type link))
+	 (raw-type (org-element-property :type link))
+	 (type (if (string= raw-type "attachment")
+		   ;; Attachments are simplified representations of
+		   ;; file links.  When exporting, expose attachments
+		   ;; as if they were file links.
+		   "file"
+		 raw-type))
 	 (raw-path (org-element-property :path link))
 	 ;; Ensure DESC really exists, or set it to nil.
 	 (desc (org-string-nw-p desc))
@@ -3073,6 +3079,11 @@ INFO is a plist holding contextual information.  See
 	   ((member type '("http" "https" "ftp" "mailto" "news"))
 	    (url-encode-url (concat type ":" raw-path)))
 	   ((string= type "file")
+	    ;; Pre-parse the path from attachment-format to
+	    ;; file-format to make attachment links use all export
+	    ;; functionality from file links with correct pathing.
+	    (when (string= raw-type "attachment")
+	      (setq raw-path (org-attach-expand raw-path)))
 	    ;; During publishing, turn absolute file names belonging
 	    ;; to base directory into relative file names.  Otherwise,
 	    ;; append "file" protocol to absolute file name.
diff --git a/lisp/ox-latex.el b/lisp/ox-latex.el
index 5db1ed7..7758abd 100644
--- a/lisp/ox-latex.el
+++ b/lisp/ox-latex.el
@@ -30,6 +30,10 @@
 (require 'ox)
 (require 'ox-publish)
 
+;;; Function Declarations
+
+(declare-function org-attach-expand "org-attach" (file))
+
 (defvar org-latex-default-packages-alist)
 (defvar org-latex-packages-alist)
 (defvar orgtbl-exp-regexp)
@@ -737,6 +741,8 @@ environment."
 
 (defcustom org-latex-inline-image-rules
   `(("file" . ,(regexp-opt
+		'("pdf" "jpeg" "jpg" "png" "ps" "eps" "tikz" "pgf" "svg")))
+    ("attachment" . ,(regexp-opt
 		'("pdf" "jpeg" "jpg" "png" "ps" "eps" "tikz" "pgf" "svg"))))
   "Rules characterizing image files that can be inlined into LaTeX.
 
@@ -2356,6 +2362,8 @@ LINK is the link pointing to the inline image.  INFO is a plist
 used as a communication channel."
   (let* ((parent (org-export-get-parent-element link))
 	 (path (let ((raw-path (org-element-property :path link)))
+		 (when (string= (org-element-property :type link) "attachment")
+		   (setq raw-path (file-relative-name (org-attach-expand raw-path))))
 		 (if (not (file-name-absolute-p raw-path)) raw-path
 		   (expand-file-name raw-path))))
 	 (filetype (file-name-extension path))
@@ -2511,7 +2519,13 @@ used as a communication channel."
 DESC is the description part of the link, or the empty string.
 INFO is a plist holding contextual information.  See
 `org-export-data'."
-  (let* ((type (org-element-property :type link))
+  (let* ((raw-type (org-element-property :type link))
+	 (type (if (string= raw-type "attachment")
+		   ;; Attachments are simplified representations of
+		   ;; file links.  When exporting, expose attachments
+		   ;; as if they were file links.
+		   "file"
+		 raw-type))
 	 (raw-path (org-element-property :path link))
 	 ;; Ensure DESC really exists, or set it to nil.
 	 (desc (and (not (string= desc "")) desc))
@@ -2521,6 +2535,8 @@ INFO is a plist holding contextual information.  See
 		(cond ((member type '("http" "https" "ftp" "mailto" "doi"))
 		       (concat type ":" raw-path))
 		      ((string= type "file")
+		       (when (string= raw-type "attachment")
+			 (setq raw-path (file-relative-name (org-attach-expand raw-path))))
 		       (org-export-file-uri raw-path))
 		      (t
 		       raw-path)))))
diff --git a/lisp/ox-man.el b/lisp/ox-man.el
index 36822ff..c98f0cd 100644
--- a/lisp/ox-man.el
+++ b/lisp/ox-man.el
@@ -40,6 +40,10 @@
 (require 'cl-lib)
 (require 'ox)
 
+;;; Function Declarations
+
+(declare-function org-attach-expand "org-attach" (file))
+
 (defvar org-export-man-default-packages-alist)
 (defvar org-export-man-packages-alist)
 (defvar orgtbl-exp-regexp)
@@ -605,14 +609,23 @@ CONTENTS is nil.  INFO is a plist holding contextual information."
 DESC is the description part of the link, or the empty string.
 INFO is a plist holding contextual information.  See
 `org-export-data'."
-  (let* ((type (org-element-property :type link))
+  (let* ((raw-type (org-element-property :type link))
+	 (type (if (string= raw-type "attachment")
+		   ;; Attachments are simplified representations of
+		   ;; file links.  When exporting, expose attachments
+		   ;; as if they were file links.
+		   "file"
+		 raw-type))
          (raw-path (org-element-property :path link))
          ;; Ensure DESC really exists, or set it to nil.
          (desc (and (not (string= desc "")) desc))
          (path (cond
                 ((member type '("http" "https" "ftp" "mailto"))
                  (concat type ":" raw-path))
-                ((string= type "file") (org-export-file-uri raw-path))
+                ((string= type "file")
+		 (when (string= raw-type "attachment")
+		   (setq raw-path (file-relative-name (org-attach-expand raw-path))))
+		 (org-export-file-uri raw-path))
                 (t raw-path))))
     (cond
      ;; Link type is handled by a special function.
diff --git a/lisp/ox-md.el b/lisp/ox-md.el
index d935ebe..d050430 100644
--- a/lisp/ox-md.el
+++ b/lisp/ox-md.el
@@ -33,6 +33,10 @@
 (require 'ox-publish)
 
 
+;;; Function Declarations
+
+(declare-function org-attach-expand "org-attach" (file))
+
 ;;; User-Configurable Variables
 
 (defgroup org-export-md nil
@@ -396,12 +400,20 @@ INFO is a plist holding contextual information.  See
 	    (if (string= ".org" (downcase (file-name-extension raw-path ".")))
 		(concat (file-name-sans-extension raw-path) ".md")
 	      raw-path)))
-	 (type (org-element-property :type link))
-	 (raw-path (raw-path (org-element-property :path link)))
+	 (raw-type (org-element-property :type link))
+	 (type (if (string= raw-type "attachment")
+		   ;; Attachments are simplified representations of
+		   ;; file links.  When exporting, expose attachments
+		   ;; as if they were file links.
+		   "file"
+		 raw-type))
+	 (raw-path (org-element-property :path link))
 	 (path (cond
 		((member type '("http" "https" "ftp" "mailto"))
-		 (concat type ":" path))
+		 (concat type ":" raw-path))
 		((string= type "file")
+		 (when (string= raw-type "attachment")
+		   (setq raw-path (file-relative-name (org-attach-expand raw-path))))
 		 (org-export-file-uri (funcall link-org-files-as-md raw-path)))
 		(t raw-path))))
     (cond
@@ -432,7 +444,7 @@ INFO is a plist holding contextual information.  See
 		(org-export-get-reference destination info))))
 	  (_
 	   (let ((description
-		  (or (org-string-nw-p contents)
+		  (or (org-string-nw-p desc)
 		      (let ((number (org-export-get-ordinal destination info)))
 			(cond
 			 ((not number) nil)
diff --git a/lisp/ox-odt.el b/lisp/ox-odt.el
index 59480cd..dd881b9 100644
--- a/lisp/ox-odt.el
+++ b/lisp/ox-odt.el
@@ -32,6 +32,10 @@
 (require 'ox)
 (require 'table nil 'noerror)
 
+;;; Function Declarations
+
+(declare-function org-attach-expand "org-attach" (file))
+
 ;;; Define Back-End
 
 (org-export-define-backend 'odt
@@ -2692,7 +2696,13 @@ Return nil, otherwise."
 DESC is the description part of the link, or the empty string.
 INFO is a plist holding contextual information.  See
 `org-export-data'."
-  (let* ((type (org-element-property :type link))
+  (let* ((raw-type (org-element-property :type link))
+	 (type (if (string= raw-type "attachment")
+		   ;; Attachments are simplified representations of
+		   ;; file links.  When exporting, expose attachments
+		   ;; as if they were file links.
+		   "file"
+		 raw-type))
 	 (raw-path (org-element-property :path link))
 	 ;; Ensure DESC really exists, or set it to nil.
 	 (desc (and (not (string= desc "")) desc))
@@ -2701,7 +2711,10 @@ INFO is a plist holding contextual information.  See
 	 (path (cond
 		((member type '("http" "https" "ftp" "mailto"))
 		 (concat type ":" raw-path))
-		((string= type "file") (org-export-file-uri raw-path))
+		((string= type "file")
+		 (when (string= raw-type "attachment")
+		   (setq raw-path (file-relative-name (org-attach-expand raw-path))))
+		 (org-export-file-uri raw-path))
 		(t raw-path)))
 	 ;; Convert & to &amp; for correct XML representation
 	 (path (replace-regexp-in-string "&" "&amp;" path)))
diff --git a/lisp/ox-texinfo.el b/lisp/ox-texinfo.el
index 4265a85..5416c8e 100644
--- a/lisp/ox-texinfo.el
+++ b/lisp/ox-texinfo.el
@@ -28,6 +28,10 @@
 (require 'cl-lib)
 (require 'ox)
 
+;;; Function Declarations
+
+(declare-function org-attach-expand "org-attach" (file))
+
 (defvar orgtbl-exp-regexp)
 
 
@@ -1045,14 +1049,23 @@ nil."
 DESC is the description part of the link, or the empty string.
 INFO is a plist holding contextual information.  See
 `org-export-data'."
-  (let* ((type (org-element-property :type link))
+  (let* ((raw-type (org-element-property :type link))
+	 (type (if (string= raw-type "attachment")
+		   ;; Attachments are simplified representations of
+		   ;; file links.  When exporting, expose attachments
+		   ;; as if they were file links.
+		   "file"
+		 raw-type))
 	 (raw-path (org-element-property :path link))
 	 ;; Ensure DESC really exists, or set it to nil.
 	 (desc (and (not (string= desc "")) desc))
 	 (path (cond
 		((member type '("http" "https" "ftp"))
 		 (concat type ":" raw-path))
-		((string= type "file") (org-export-file-uri raw-path))
+		((string= type "file")
+		 (when (string= raw-type "attachment")
+		   (setq raw-path (org-attach-expand raw-path)))
+		 (org-export-file-uri raw-path))
 		(t raw-path))))
     (cond
      ((org-export-custom-protocol-maybe link desc 'texinfo))