* net/xesam.el (top): Require `wid-edit' always.

(xesam-mode-line, xesam-highlight): New deffaces.
(xesam-objects): New local variable.
(xesam-search-engines): Fix error in field list.
(xesam-mode): Use `xesam-mode-line' instead of
`font-lock-type-face'.  Apply `xesam-mode' to a temp buffer, for
proper initiatilzaion (why?).
(xesam-highlight-string, xesam-get-hits)
(xesam-kill-buffer-function): New defuns.
(xesam-refresh-entry): Move code to `xesam-get-hits'.  Check
result of "hit.fields", it isn't a string only.  Wrap an error of
the strigi search engine ("xesam:size" is returned as string).
Highlight search items.
(xesam-refresh-search-buffer): Make logic of counters more simple.
Prefetch next hits.
(xesam-signal-handler): Use `xesam-mode-line' instead of
`font-lock-type-face'.
(xesam-new-search): Add `xesam-kill-buffer-function' to
`kill-buffer-hook'.

2 files changed, 120 insertions, 41 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 9b0e652701e..3af0ce170bd 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,25 @@
+2008-08-05  Michael Albinus  <michael.albinus@gmx.de>
+
+        * net/xesam.el (top): Require `wid-edit' always.
+        (xesam-mode-line, xesam-highlight): New deffaces.
+        (xesam-objects): New local variable.
+        (xesam-search-engines): Fix error in field list.
+        (xesam-mode): Use `xesam-mode-line' instead of
+        `font-lock-type-face'.  Apply `xesam-mode' to a temp buffer, for
+        proper initiatilzaion (why?).
+        (xesam-highlight-string, xesam-get-hits)
+        (xesam-kill-buffer-function): New defuns.
+        (xesam-refresh-entry): Move code to `xesam-get-hits'.  Check
+        result of "hit.fields", it isn't a string only.  Wrap an error of
+        the strigi search engine ("xesam:size" is returned as string).
+        Highlight search items.
+        (xesam-refresh-search-buffer): Make logic of counters more simple.
+        Prefetch next hits.
+        (xesam-signal-handler): Use `xesam-mode-line' instead of
+        `font-lock-type-face'.
+        (xesam-new-search): Add `xesam-kill-buffer-function' to
+        `kill-buffer-hook'.
+
 2008-08-05  Teodor Zlatanov  <tzz@lifelogs.com>
 
         * add-log.el (change-log-next-error, change-log-mode): Add support
diff --git a/lisp/net/xesam.el b/lisp/net/xesam.el
index c864bc2cb83..36a6b49f6e7 100644
--- a/lisp/net/xesam.el
+++ b/lisp/net/xesam.el
@@ -117,9 +117,7 @@
 
 ;; Widgets are used to highlight the search results.
 (require 'widget)
-
-(eval-when-compile
-  (require 'wid-edit))
+(require 'wid-edit)
 
 ;; `run-at-time' is used in the signal handler.
 (require 'timer)
@@ -141,10 +139,20 @@
           (const :tag "Xesam fulltext query" fulltext-query)))
 
 (defcustom xesam-hits-per-page 20
-  "Number of search hits to be displayed in the result buffer"
+  "Number of search hits to be displayed in the result buffer."
   :group 'xesam
   :type 'integer)
 
+(defface xesam-mode-line '((t :inherit mode-line-emphasis))
+  "Face to highlight mode line."
+  :group 'xesam)
+
+(defface xesam-highlight '((t :inherit match))
+  "Face to highlight query entries.
+It will be overlayed by `widget-documentation-face', so it shall
+be different at least in one face property not set in that face."
+  :group 'xesam)
+
 (defvar xesam-debug nil
   "Insert debug information in the help echo.")
 
@@ -294,6 +302,7 @@ from VALUE, depending on what the search engine accepts."
 (defvar xesam-type nil)
 (defvar xesam-query nil)
 (defvar xesam-xml-string nil)
+(defvar xesam-objects nil)
 (defvar xesam-current nil)
 (defvar xesam-count nil)
 (defvar xesam-to nil)
@@ -376,7 +385,7 @@ If there is no registered search engine at all, the function returns `nil'."
                ((string-equal vendor-id "Beagle")
                 '("xesam:mimeType" "xesam:url"))
                ((string-equal vendor-id "Strigi")
-                '("xesam:author" "xesam:cc" "xesam:cc" "xesam:charset"
+                '("xesam:author" "xesam:cc" "xesam:charset"
                   "xesam:contentType" "xesam:fileExtension" "xesam:id"
                   "xesam:lineCount" "xesam:links" "xesam:mimeType" "xesam:name"
                   "xesam:size" "xesam:sourceModified" "xesam:subject"
@@ -420,6 +429,7 @@ Turning on Xesam mode runs the normal hook `xesam-mode-hook'."
   (set (make-local-variable 'xesam-type) "")
   (set (make-local-variable 'xesam-query) "")
   (set (make-local-variable 'xesam-xml-string) "")
+  (set (make-local-variable 'xesam-objects) nil)
   ;; `xesam-current' is the last hit put into the search buffer,
   (set (make-local-variable 'xesam-current) 0)
   ;; `xesam-count' is the number of hits reported by the search engine.
@@ -439,13 +449,13 @@ Turning on Xesam mode runs the normal hook `xesam-mode-hook'."
        (list '(20
                (:eval
                 (list "Type: "
-                      (propertize xesam-type 'face 'font-lock-type-face))))
+                      (propertize xesam-type 'face 'xesam-mode-line))))
              '(10
                (:eval
                 (list " Query: "
                       (propertize
                        xesam-query
-                       'face 'font-lock-type-face
+                       'face 'xesam-mode-line
                        'help-echo (when xesam-debug xesam-xml-string)))))))
 
   (when (not (interactive-p))
@@ -457,28 +467,30 @@ Turning on Xesam mode runs the normal hook `xesam-mode-hook'."
 ;; It doesn't make sense to call it interactively.
 (put 'xesam-mode 'disabled t)
 
+;; The very first buffer created with `xesam-mode' does not have the
+;; keymap etc.  So we create a dummy buffer.  Stupid.
+(with-temp-buffer (xesam-mode))
+
 (defun xesam-buffer-name (service search)
   "Return the buffer name where to present search results.
 SERVICE is the D-Bus unique service name of the Xesam search engine.
 SEARCH is the search identification in that engine.  Both must be strings."
   (format "*%s/%s*" service search))
 
-(defun xesam-refresh-entry (engine search)
+(defun xesam-highlight-string (string)
+  "Highlight text enclosed by <b> and </b>."
+  (while (string-match "\\(.*\\)\\(<b>\\)\\(.*\\)\\(</b>\\)\\(.*\\)" string)
+    (setq string
+          (format
+           "%s%s%s"
+           (match-string 1 string)
+           (propertize (match-string 3 string) 'face 'xesam-highlight)
+           (match-string 5 string))))
+  string)
+
+(defun xesam-refresh-entry (engine entry)
   "Refreshes one entry in the search buffer."
-  (let* ((result
-          (car
-           (xesam-dbus-call-method
-            :session (car engine) xesam-path-search
-            xesam-interface-search "GetHits" search 1)))
-         (snippet)
-         ;; We must disable this for the time being; the search
-         ;; engines don't return usable values so far.
-;         (caaar
-;          (dbus-ignore-errors
-;            (xesam-dbus-call-method
-;             :session  (car engine) xesam-path-search
-;             xesam-interface-search "GetHitData"
-;             search (list xesam-current) '("snippet")))))
+  (let* ((result (nth (1- xesam-current) xesam-objects))
          widget)
 
     ;; Create widget.
@@ -488,7 +500,10 @@ SEARCH is the search identification in that engine.  Both must be strings."
 
     ;; Take all results.
     (dolist (field (xesam-get-cached-property engine "hit.fields"))
-      (when (not (zerop (length (caar result))))
+      (when (cond
+             ((stringp (caar result)) (not (zerop (length (caar result)))))
+             ((numberp (caar result)) (not (zerop (caar result))))
+             ((caar result) t))
         (when xesam-debug
           (widget-put
            widget :help-echo
@@ -503,6 +518,12 @@ SEARCH is the search identification in that engine.  Both must be strings."
       (widget-put
        widget :xesam:url (concat "file://" (widget-get widget :xesam:url))))
 
+    ;; Strigi returns xesam:size as string.  We must fix this.
+    (when (and (widget-member widget :xesam:size)
+               (stringp (widget-get widget :xesam:size)))
+      (widget-put
+       widget :xesam:size (string-to-number (widget-get widget :xesam:url))))
+
     ;; First line: :tag.
     (cond
      ((widget-member widget :xesam:title)
@@ -514,6 +535,11 @@ SEARCH is the search identification in that engine.  Both must be strings."
      ((widget-member widget :xesam:name)
       (widget-put widget :tag (widget-get widget :xesam:name))))
 
+    ;; Highlight the search items.
+    (when (widget-member widget :tag)
+      (widget-put
+       widget :tag (xesam-highlight-string (widget-get widget :tag))))
+
     ;; Last Modified.
     (when (widget-member widget :xesam:sourceModified)
       (widget-put
@@ -556,11 +582,12 @@ SEARCH is the search identification in that engine.  Both must be strings."
       (widget-put widget :doc (widget-get widget :xesam:snippet))))
 
     (when (widget-member widget :doc)
-      (widget-put widget :help-echo (widget-get widget :doc))
       (with-temp-buffer
-        (insert (widget-get widget :doc))
+        (insert
+         (xesam-highlight-string (widget-get widget :doc)))
         (fill-region-as-paragraph (point-min) (point-max))
-        (widget-put widget :doc (buffer-string))))
+        (widget-put widget :doc (buffer-string)))
+      (widget-put widget :help-echo (widget-get widget :doc)))
 
     ;; Format the widget.
     (widget-put
@@ -576,24 +603,38 @@ SEARCH is the search identification in that engine.  Both must be strings."
     (force-mode-line-update)
     (redisplay)))
 
+(defun xesam-get-hits (engine search hits)
+  "Retrieve hits from ENGINE."
+  (with-current-buffer (xesam-buffer-name (car engine) search)
+    (setq xesam-objects
+          (append xesam-objects
+                  (xesam-dbus-call-method
+                   :session (car engine) xesam-path-search
+                   xesam-interface-search "GetHits" search hits)))))
+
 (defun xesam-refresh-search-buffer (engine search)
   "Refreshes the buffer, presenting results of SEARCH."
   (with-current-buffer (xesam-buffer-name (car engine) search)
     ;; Work only if nobody else is here.
-    (unless xesam-refreshing
+    (unless (or xesam-refreshing (>= xesam-current xesam-to))
       (setq xesam-refreshing t)
       (unwind-protect
-          (let (widget updated)
-            ;; Add all result widgets.  The upper boundary is always
-            ;; computed, because new hits might have arrived while
-            ;; running.
+          (let (widget)
+
+            ;; Retrieve needed hits for visualization.
+            (while (> (min xesam-to xesam-count) (length xesam-objects))
+              (xesam-get-hits
+               engine search
+               (min xesam-hits-per-page
+                    (- (min xesam-to xesam-count) (length xesam-objects)))))
+
+            ;; Add all result widgets.
             (while (< xesam-current (min xesam-to xesam-count))
-              (setq updated t
-                    xesam-current (1+ xesam-current))
+              (setq xesam-current (1+ xesam-current))
               (xesam-refresh-entry engine search))
 
             ;; Add "NEXT" widget.
-            (when (and updated (> xesam-count xesam-to))
+            (when (> xesam-count xesam-to)
               (goto-char (point-max))
               (widget-create
                'link
@@ -603,7 +644,16 @@ SEARCH is the search identification in that engine.  Both must be strings."
                   (widget-delete widget)
                   (xesam-refresh-search-buffer xesam-engine xesam-search))
                "NEXT")
-              (widget-beginning-of-line)))
+              (widget-beginning-of-line))
+
+            ;; Prefetch next hits.
+            (when (> (min (+ xesam-hits-per-page xesam-to) xesam-count)
+                     (length xesam-objects))
+              (xesam-get-hits
+               engine search
+               (min xesam-hits-per-page
+                    (- (min (+ xesam-hits-per-page xesam-to) xesam-count)
+                       (length xesam-objects))))))
 
         ;; Return with save settings.
         (setq xesam-refreshing nil)))))
@@ -632,9 +682,16 @@ SEARCH is the search identification in that engine.  Both must be strings."
 
          ((string-equal member "SearchDone")
           (setq mode-line-process
-                (propertize " Done" 'face 'font-lock-type-face))
+                (propertize " Done" 'face 'xesam-mode-line))
           (force-mode-line-update)))))))
 
+(defun xesam-kill-buffer-function ()
+  "Send the CloseSearch indication."
+  (when (and (eq major-mode 'xesam-mode) (stringp xesam-search))
+    (xesam-dbus-call-method
+     :session (car xesam-engine) xesam-path-search
+     xesam-interface-search "CloseSearch" xesam-search)))
+
 (defun xesam-new-search (engine type query)
   "Create a new search session.
 ENGINE identifies the search engine.  TYPE is the query type, it
@@ -675,6 +732,7 @@ search, is returned."
             xesam-type (symbol-name type)
             xesam-query query
             xesam-xml-string xml-string
+            xesam-objects nil
             ;; The buffer identification shall indicate the search
             ;; engine.  The `help-echo' property is used for debug
             ;; information, when applicable.
@@ -694,7 +752,8 @@ search, is returned."
                   "vendor.ontology.sources" "vendor.extensions"
                   "vendor.ontologies" "vendor.maxhits")
                 "\n"))))
-          (force-mode-line-update))
+      (add-hook 'kill-buffer-hook 'xesam-kill-buffer-function)
+      (force-mode-line-update))
 
     ;; Start the search.
     (xesam-dbus-call-method
@@ -748,18 +807,16 @@ Example:
 
 ;;; TODO:
 
-;; * Solve error, that xesam-mode does not work the very first time.
-;; * Retrieve several results at once.
-;; * Retrieve hits for the next page in advance.
+;; * Accept input while retrieving prefetched hits. `run-at-time'?
 ;; * With prefix, let's choose search engine.
 ;; * Minibuffer completion for user queries.
 ;; * `revert-buffer-function' implementation.
-;; * Close search when search buffer is killed.
 ;;
 ;; * Mid term
 ;;   - If available, use ontologies for field selection.
 ;;   - Search engines for Emacs bugs database, wikipedia, google,
 ;;     yahoo, ebay, ...
+;;   - Construct complex queries via widgets, like in mairix.el.
 
 ;; arch-tag: 7fb9fc6c-c2ff-4bc7-bb42-bacb80cce2b2
 ;;; xesam.el ends here