feat: implement controls bar

Also includes a lot of refactoring around codebase to make it work as needed.

Notable addition: new `items` command that displays playlist if any, or open-file otherwise.

ref #167, closes #71

README.md

@@ -182,6 +182,10 @@ Switch stream quality. This is just a basic re-assignment of `ytdl-format` mpv p
 
 Open file menu. Browsing starts in current file directory, or user directory when file not available.
 
+#### `items`
+
+Opens `playlist` menu when playlist exists, or `open-file` menu otherwise.
+
 #### `next`
 
 Open next item in playlist, or file in current directory when there is no playlist.

script-opts/uosc.conf

@@ -14,7 +14,7 @@ timeline_size_min_fullscreen=0
 timeline_size_max_fullscreen=60
 # same thing as calling toggle-progress command once on startup
 timeline_start_hidden=no
-# comma separated states when timeline should always be visible. available: paused, audio
+# comma separated states when timeline should always be visible. available: paused, audio, image, video
 timeline_persistency=
 # timeline opacity
 timeline_opacity=0.9
@@ -32,6 +32,52 @@ timeline_chapters=dots
 timeline_chapters_opacity=0.2
 timeline_chapters_width=6
 
+# A comma delimited list of elements to construct the controls bar above the timeline. Set to `never` to disable.
+# Parameter spec: enclosed in `{}` means value, enclosed in `[]` means optional
+# Common properties:
+#   `{icon}` - parameter used to specify an icon name (example: `face`)
+#            - you can pick one here: https://fonts.google.com/icons?selected=Material+Icons
+# Available elements and their parameters:
+#   `{usoc_command}` - preconfigured shorthands for uosc commands that make sense to have as buttons:
+#      - `menu`, `subtitles`, `audio`, `video`, `playlist`, `chapters`, `stream-quality`,
+#        `open-file`, `items`, `next`, `prev`, `first`, `last`, `audio-device`
+#   `fullscreen` - toggle fullscreen
+#   `loop-playlist` - button to toggle playlist looping
+#   `loop-file` - button to toggle current file looping
+#   `speed[:{scale}]` - display speed slider, [{scale}] - factor of controls_size, default: 1.3
+#   `command:{icon}:{command}` - button that executes a {command} when pressed
+#   `toggle:{icon}:{prop}` - button that toggles mpv property
+#   `cycle:{default_icon}:{prop}:{value1}[={icon1}][!]/{valueN}[={iconN}][!]`
+#     - button that cycles mpv property between values, each optionally having different icon and active flag
+#     - presence of `!` at the end will style the button as active
+#   `gap[:{scale}]` - display an empty gap, {scale} - factor of controls_size, default: 0.3
+#   `space` - fills all available space between previous and next item, useful to align items to the right
+#           - multiple spaces divide the available space among themselves, which can be used for centering
+#   Example implementations of some of the shorthands:
+#   - menu: `command:menu:script-binding uosc/menu`
+#   - fullscreen: `cycle:fullscreen:fullscreen:no/yes=fullscreen_exit!`
+#   - loop-playlist: `cycle:repeat:loop-playlist:no/inf!`
+#   - `toggle:{icon}:{prop}`: `cycle:{icon}:{prop}:no/yes!`
+# Element visibility control:
+#   `<[!]{disposition1}[,[!]{dispositionN}]>` - optional prefix to control element's visibility
+#   - `{disposition}` can be one of:
+#     - `image` - true if current file is a single image
+#     - `audio` - true for audio only files
+#     - `video` - true for files with a video track
+#     - `has_audio` - true for files with an audio track
+#     - `stream` - true if current file is read from a stream
+#     - `has_playlist` - true if current playlist has 2 or more items in it
+#   - prefix with `!` to negate the required disposition
+#   Examples:
+#     - `<stream>stream-quality` - show stream quality button only for streams
+#     - `<has_audio,!audio>audio` - show audio tracks button for all files that have
+#                                   an audio track, but are not exclusively audio only files
+controls=menu,gap,subtitles,<has_audio,!audio>audio,<stream>stream-quality,gap,loop-playlist,loop-file,space,speed,space,prev,items,next,shuffle,gap:1,fullscreen
+controls_size=32
+controls_size_fullscreen=40
+controls_margin=8
+controls_spacing=2
+
 # where to display volume controls: none, left, right
 volume=right
 volume_size=40
@@ -63,15 +109,6 @@ menu_opacity=0.8
 menu_parent_opacity=0.4
 menu_font_scale=1
 
-# menu button widget
-# can be: never, bottom-bar, center
-menu_button=never
-menu_button_size=26
-menu_button_size_fullscreen=30
-menu_button_persistency=
-menu_button_opacity=1
-menu_button_border=1
-
 # top bar with window controls and media title
 # can be: never, no-border, always
 top_bar=no-border