docs: document viewer

GitHub: closes #128

1 files changed, 37 insertions, 8 deletions

diff --git a/viewer/ldgallery-viewer.7.md b/viewer/ldgallery-viewer.7.md
index 0711496..da3be76 100644
--- a/viewer/ldgallery-viewer.7.md
+++ b/viewer/ldgallery-viewer.7.md
@@ -1,6 +1,6 @@
 ---
 pagetitle: Viewer user manual - ldgallery
-title: LDGALLERY-VIEWER(7) ldgallery viewer
+title: LDGALLERY-VIEWER(7) ldgallery
 author: Pacien TRAN-GIRARD, Guillaume FOUET
 date: 2020-02-16 (v0.1.0.0-SNAPSHOT)
 ---
@@ -8,30 +8,59 @@ date: 2020-02-16 (v0.1.0.0-SNAPSHOT)
 
 # NAME
 
-ldgallery viewer - a static web gallery with tags
+ldgallery viewer - a static web gallery viewer with tags
 
 
 # DESCRIPTION
 
-TODO
+The ldgallery viewer is a web application that allows users to browse, search through and view items in galleries generated by the ldgallery(1) compiler.
+
+The web application runs in a JavaScript-enabled web browser and does not require any special software on the server's side.  Its responsiveness allows it to be used from either a desktop browser or some mobile device.
 
 
 # USER INTERFACE
 
-TODO
+The viewer's user interface is split into a main item view and a side search panel, which can be opened by using the appropriate button in the toolbar at the top-left corner.
+
+The main view displays the gallery's directories and items as a thumbnail grid.
+
+The side panel allows the user to interactively enter filtering queries to search through the gallery's content.  This panel features a list of relevant tags that can be used to build the search query.
+
+Picture items can be opened and visualised within the application.  Other types of elements are either downloaded or displayed in the same window depending on the user's web browser supported media types.
 
 
 # SEARCH QUERIES
 
-TODO
+Items can be filtered based on their tags.
+Adding tags to the search query restricts the search results to items having those tags.
+
+The following modifiers can be used in queries as prefixes of tags:
+
+`+`
+: Include all items having the associated tag,
+  independently of simple tag restrictions.
+
+`-`
+: Exclude all items having the associated tag,
+  independently of simple tag restrictions and inclusions.
+
+
+<!-- TODO: document tag groups and disambiguation once they're fully implemented (#29) -->
 
 
 # VIEWER CONFIGURATION
 
-TODO
+The viewer itself can be configured through a JSON file named `config.json` and placed in the web viewer's directory.
+
+galleryRoot
+: Absolute or relative path to the root of the gallery to display.
+
+
+# PROGRESSIVE WEB APPLICATION
+
+This web application can be "installed" on some user's mobile device as a progressive web application, i.e. a shortcut giving the web page the appearance of a native application.
 
-key.key
-: Details
+This feature can be enabled by adding a PWA manifest in the viewer's directory when deployed.  An example of such manifest and an associated icon are available in the example folder packaged with the viewer.
 
 
 # SEE ALSO