init 0.1.0

17 files changed, 1389 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
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--- /dev/null
+++ b/.gitignore
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+build/
+result
+.cache/
+test.sh
+tmp/
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..f288702
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,674 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
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+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program 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 of the License, or
+    (at your option) any later version.
+
+    This program 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 this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..9546d7e
--- /dev/null
+++ b/README.md
@@ -0,0 +1,7 @@
+# astal-battery
+
+DBus proxy library for upower daemeon
+
+## TODO
+
+- docs
diff --git a/flake.lock b/flake.lock
new file mode 100644
index 0000000..13f566b
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,27 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1716137900,
+        "narHash": "sha256-sowPU+tLQv8GlqtVtsXioTKeaQvlMz/pefcdwg8MvfM=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "6c0b7a92c30122196a761b440ac0d46d3d9954f1",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 0000000..ba7aa74
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,48 @@
+{
+  description = "DBus proxy library for upower daemon";
+
+  inputs.nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
+
+  outputs = { self, nixpkgs }:
+  let
+    version = builtins.replaceStrings ["\n"] [""] (builtins.readFile ./version);
+    system = "x86_64-linux";
+    pkgs = import nixpkgs { inherit system; };
+
+    nativeBuildInputs = with pkgs; [
+      gobject-introspection
+      meson
+      pkg-config
+      ninja
+      vala
+    ];
+
+    buildInputs = with pkgs; [
+      glib
+    ];
+  in {
+    packages.${system} = rec {
+      default = battery;
+      battery = pkgs.stdenv.mkDerivation {
+        inherit nativeBuildInputs buildInputs;
+        pname = "astal-battery";
+        version = version;
+        src = ./.;
+        outputs = ["out" "dev"];
+      };
+    };
+
+    devShells.${system} = {
+      default = pkgs.mkShell {
+        inherit nativeBuildInputs buildInputs;
+      };
+      battery = pkgs.mkShell {
+        inherit nativeBuildInputs;
+        buildInputs = buildInputs ++ [
+          self.packages.${system}.default
+          pkgs.gjs
+        ];
+      };
+    };
+  };
+}
diff --git a/meson.build b/meson.build
new file mode 100644
index 0000000..6621735
--- /dev/null
+++ b/meson.build
@@ -0,0 +1,19 @@
+project(
+  'astal-battery',
+  'vala',
+  'c',
+  version: run_command('cat', join_paths(meson.project_source_root(), 'version')).stdout().strip(),
+  meson_version: '>= 0.62.0',
+  default_options: [
+    'warning_level=2',
+    'werror=false',
+    'c_std=gnu11',
+  ],
+)
+
+assert(
+  get_option('lib') or get_option('cli'),
+  'Either lib or cli option must be set to true.',
+)
+
+subdir('src')
diff --git a/meson_options.txt b/meson_options.txt
new file mode 100644
index 0000000..f110242
--- /dev/null
+++ b/meson_options.txt
@@ -0,0 +1,11 @@
+option(
+  'lib',
+  type: 'boolean',
+  value: true,
+)
+
+option(
+  'cli',
+  type: 'boolean',
+  value: true,
+)
diff --git a/src/cli.vala b/src/cli.vala
new file mode 100644
index 0000000..85e70ae
--- /dev/null
+++ b/src/cli.vala
@@ -0,0 +1,50 @@
+static bool help;
+static bool version;
+static bool monitor;
+
+const OptionEntry[] options = {
+    { "version", 'v', OptionFlags.NONE, OptionArg.NONE, ref version, null, null },
+    { "help", 'h', OptionFlags.NONE, OptionArg.NONE, ref help, null, null },
+    { "monitor", 'm', OptionFlags.NONE, OptionArg.NONE, ref monitor, null, null },
+    { null },
+};
+
+int main(string[] argv) {
+    try {
+        var opts = new OptionContext();
+        opts.add_main_entries(options, null);
+        opts.set_help_enabled(false);
+        opts.set_ignore_unknown_options(false);
+        opts.parse(ref argv);
+    } catch (OptionError err) {
+        printerr (err.message);
+        return 1;
+    }
+
+    if (help) {
+        print("Usage:\n");
+        print("    %s [flags]\n\n", argv[0]);
+        print("Flags:\n");
+        print("    -h, --help        Print this help and exit\n");
+        print("    -v, --version     Print version number and exit\n");
+        print("    -m, --monitor     Monitor property changes\n");
+        return 0;
+    }
+
+    if (version) {
+        print(AstalBattery.VERSION);
+        return 0;
+    }
+
+    var battery = AstalBattery.get_default();
+    print("%s\n", AstalBattery.to_json(battery));
+
+    if (monitor) {
+        battery.notify.connect(() => {
+            print("%s\n", AstalBattery.to_json(battery));
+        });
+        new GLib.MainLoop(null, false).run();
+    }
+
+    return 0;
+}
diff --git a/src/config.vala.in b/src/config.vala.in
new file mode 100644
index 0000000..6e7f77e
--- /dev/null
+++ b/src/config.vala.in
@@ -0,0 +1,6 @@
+namespace AstalBattery {
+    public const int MAJOR_VERSION = @MAJOR_VERSION@;
+    public const int MINOR_VERSION = @MINOR_VERSION@;
+    public const int MICRO_VERSION = @MICRO_VERSION@;
+    public const string VERSION = "@VERSION@";
+}
diff --git a/src/device.vala b/src/device.vala
new file mode 100644
index 0000000..2dc03eb
--- /dev/null
+++ b/src/device.vala
@@ -0,0 +1,148 @@
+namespace AstalBattery {
+public Device get_default() {
+    return Device.get_default();
+}
+
+public class Device : Object {
+    private static Device display_device;
+    public static Device? get_default() {
+        if (display_device != null)
+            return display_device;
+
+        try {
+            display_device = new Device(
+                    "/org/freedesktop/UPower/devices/DisplayDevice");
+
+            return display_device;
+        } catch (Error error) {
+            critical(error.message);
+        }
+        return null;
+    }
+
+    private Properties props;
+    private IUPowerDevice proxy;
+
+    public DeviceType device_type {
+        get {
+            Value value = Value(Type.UINT);
+            proxy.get_property("name", ref value);
+            return value.get_uint();
+        }
+    }
+
+    public string native_path { owned get { return proxy.native_path; } }
+    public string vendor { owned get { return proxy.vendor; } }
+    public string model { owned get { return proxy.model; } }
+    public string serial { owned get { return proxy.serial; } }
+    public uint64 update_time { get { return proxy.update_time; } }
+    public bool power_supply { get { return proxy.power_supply; } }
+    public bool has_history { get { return proxy.has_history; } }
+    public bool has_statistics { get { return proxy.has_statistics; } }
+    public bool online { get { return proxy.online; } }
+    public double energy { get { return proxy.energy; } }
+    public double energy_empty { get { return proxy.energy_empty; } }
+    public double energy_full { get { return proxy.energy_full; } }
+    public double energy_full_design { get { return proxy.energy_full_design; } }
+    public double energy_rate { get { return proxy.energy_rate; } }
+    public double voltage { get { return proxy.voltage; } }
+    public int charge_cycles { get { return proxy.charge_cycles; } }
+    public double luminosity { get { return proxy.luminosity; } }
+    public int64 time_to_empty { get { return proxy.time_to_empty; } }
+    public int64 time_to_full { get { return proxy.time_to_full; }}
+    public double percentage { get { return proxy.percentage / 100; } }
+    public double temperature { get { return proxy.temperature; } }
+    public bool is_present { get { return proxy.is_present; } }
+    public DeviceState state { get { return proxy.state; } }
+    public bool is_rechargable { get { return proxy.is_rechargable; } }
+    public double capacitiy { get { return proxy.capacitiy; } }
+    public DeviceTechnology technology { get { return proxy.technology; } }
+    public WarningLevel warning_level { get { return proxy.warning_level; } }
+    public BatteryLevel battery_level { get { return proxy.battery_level; } }
+    public string icon_name { owned get { return proxy.icon_name; } }
+
+    public Device(string path) throws Error {
+        proxy = Bus.get_proxy_sync(BusType.SYSTEM, "org.freedesktop.UPower", path);
+        props = Bus.get_proxy_sync(BusType.SYSTEM, "org.freedesktop.UPower", path);
+
+        props.properties_changed.connect((iface, vardict) => {
+            foreach (var key in vardict.get_keys()) {
+                var prop = pascal_to_kebab_case(key);
+                if (get_class().find_property(prop) != null)
+                    notify_property(prop);
+            }
+        });
+    }
+}
+
+public enum DeviceType {
+    UNKNOWN = 0,
+    LINE_POWER,
+    BATTERY,
+    UPS,
+    MONITOR,
+    MOUSE,
+    KEYBOARD,
+    PDA,
+    PHONE,
+    MEDIA_PLAYER,
+    TABLET,
+    COMPUTER,
+    GAMING_INPUT,
+    PEN,
+    TOUCHPAD,
+    MODEM,
+    NETWORK,
+    HEADSET,
+    SPEAKERS,
+    HEADPHONES,
+    VIDEO,
+    OTHER_AUDIO,
+    REMOVE_CONTROL,
+    PRINTER,
+    SCANNER,
+    CAMERA,
+    WEARABLE,
+    TOY,
+    BLUETOOTH_GENERIC,
+}
+
+public enum DeviceState {
+    UNKNOWN = 0,
+    CHARGING,
+    DISCHARGING,
+    EMPTY,
+    FULLY_CHARGED,
+    PENDING_CHARGE,
+    PENDING_DISCHARGE,
+}
+
+public enum DeviceTechnology {
+    UNKNOWN = 0,
+    LITHIUM_ION,
+    LITHIUM_POLYMER,
+    LITHIUM_IRON_PHOSPHATE,
+    LEAD_ACID,
+    NICKEL_CADMIUM,
+    NICKEL_METAL_HYDRIDE,
+}
+
+public enum WarningLevel {
+    UNKNOWN = 0,
+    NONE,
+    DISCHARGING,
+    LOW,
+    CRITICIAL,
+    ACTION,
+}
+
+public enum BatteryLevel {
+    UNKNOWN = 0,
+    NONE,
+    LOW,
+    CRITICIAL,
+    NORMAL,
+    HIGH,
+    FULL,
+}
+}
diff --git a/src/ifaces.vala b/src/ifaces.vala
new file mode 100644
index 0000000..9c769d1
--- /dev/null
+++ b/src/ifaces.vala
@@ -0,0 +1,90 @@
+namespace AstalBattery {
+[DBus (name = "org.freedesktop.DBus.Properties")]
+public interface Properties : Object {
+    public signal void properties_changed (
+        string iface_name,
+        HashTable<string, Variant> props,
+        string[] invalidated_props
+    );
+}
+
+[DBus (name = "org.freedesktop.UPower")]
+interface IUPower : Object {
+    public abstract string[] enumerate_devices() throws Error;
+    public abstract string get_display_device() throws Error;
+    public abstract string get_critical_action() throws Error;
+
+    public signal void device_added(string object_path);
+    public signal void device_removed(string object_path);
+
+    public abstract string daemon_version { owned get; }
+    public abstract bool on_battery { get; }
+    public abstract bool lid_is_closed { get; }
+    public abstract bool lis_is_present { get; }
+}
+
+[DBus (name = "org.freedesktop.UPower.KbdBacklight")]
+interface IUPowerKdbBacklight : Object {
+    public abstract int get_brightness() throws Error;
+    public abstract int get_max_brightness() throws Error;
+    public abstract void set_brightness(int value) throws Error;
+
+    public signal void brightness_changed(int value);
+    public signal void brightness_changed_with_source(int value, string source);
+}
+
+[DBus (name = "org.freedesktop.UPower.Device")]
+public interface IUPowerDevice : Object {
+    // public abstract void refresh() throws Error;
+    // public abstract void get_history();
+    // public abstract void get_statistics();
+
+    // incompatible with gobject
+    // public abstract uint type { get; }
+    public abstract string native_path { owned get; }
+    public abstract string vendor { owned get; }
+    public abstract string model { owned get; }
+    public abstract string serial { owned get; }
+    public abstract uint64 update_time { get; }
+    public abstract bool power_supply { get; }
+    public abstract bool has_history { get; }
+    public abstract bool has_statistics { get; }
+    public abstract bool online { get; }
+    public abstract double energy { get; }
+    public abstract double energy_empty { get; }
+    public abstract double energy_full { get; }
+    public abstract double energy_full_design { get; }
+    public abstract double energy_rate { get; }
+    public abstract double voltage { get; }
+    public abstract int charge_cycles { get; }
+    public abstract double luminosity { get; }
+    public abstract int64 time_to_empty { get; }
+    public abstract int64 time_to_full { get; }
+    public abstract double percentage { get; }
+    public abstract double temperature { get; }
+    public abstract bool is_present { get; }
+    public abstract uint state { get; }
+    public abstract bool is_rechargable { get; }
+    public abstract double capacitiy { get; }
+    public abstract uint technology { get; }
+    public abstract uint warning_level { get; }
+    public abstract uint battery_level { get; }
+    public abstract string icon_name { owned get; }
+}
+
+[DBus (name = "org.freedesktop.UPower.PowerProfiles")]
+public interface IPowerProfiles : Object {
+    public abstract string[] actions { owned get; }
+    public abstract string active_profile { owned get; }
+    public abstract HashTable<string, Variant>[] active_profile_holds { owned get; }
+    public abstract string performance_degraded { owned get; }
+    public abstract string performance_inhibited { owned get; }
+    public abstract HashTable<string, Variant>[] profiles { owned get; }
+    public abstract string version { owned get; }
+
+    public signal uint profile_released (uint cookie);
+
+    public abstract uint hold_profile(string profile, string reason, string application_id) throws Error;
+    public abstract void release_profile(uint cookie) throws Error;
+}
+}
diff --git a/src/kbd.vala b/src/kbd.vala
new file mode 100644
index 0000000..13d722e
--- /dev/null
+++ b/src/kbd.vala
@@ -0,0 +1,64 @@
+namespace AstalBattery {
+public KbdBacklight get_keyboard() {
+    return KbdBacklight.get_default();
+}
+
+public class KbdBacklight : Object {
+    private IUPowerKdbBacklight proxy;
+
+    private static KbdBacklight instance;
+    public static KbdBacklight? get_default() {
+        if (instance != null)
+            return instance;
+
+        try {
+            instance = new KbdBacklight();
+            return instance;
+        } catch (Error error) {
+            critical(error.message);
+            return null;
+        }
+    }
+
+    public int brightness {
+        get {
+            try {
+                return proxy.get_brightness();
+            } catch (Error error) {
+                critical(error.message);
+                return 0;
+            }
+        }
+        set {
+            try {
+                proxy.set_brightness(value);
+            } catch (Error error) {
+                critical(error.message);
+            }
+        }
+    }
+
+    public int max_brightness {
+        get {
+            try {
+                return proxy.get_max_brightness();
+            } catch (Error error) {
+                critical(error.message);
+                return 0;
+            }
+        }
+    }
+
+    public KbdBacklight() throws Error {
+        proxy = Bus.get_proxy_sync(
+            BusType.SYSTEM,
+            "org.freedesktop.UPower",
+            "/org/freedesktop/UPower/KbdBacklight"
+        );
+
+        proxy.brightness_changed.connect(() => {
+            notify_property("brightness");
+        });
+    }
+}
+}
diff --git a/src/meson.build b/src/meson.build
new file mode 100644
index 0000000..9de2aad
--- /dev/null
+++ b/src/meson.build
@@ -0,0 +1,80 @@
+version_split = meson.project_version().split('.')
+api_version = version_split[0] + '.' + version_split[1]
+gir = 'AstalBattery-' + api_version + '.gir'
+typelib = 'AstalBattery-' + api_version + '.typelib'
+so = 'lib' + meson.project_name() + '.so.' + meson.project_version()
+
+config = configure_file(
+  input: 'config.vala.in',
+  output: 'config.vala',
+  configuration: {
+    'VERSION': meson.project_version(),
+    'MAJOR_VERSION': version_split[0],
+    'MINOR_VERSION': version_split[1],
+    'MICRO_VERSION': version_split[2],
+  },
+)
+
+deps = [
+  dependency('glib-2.0'),
+  dependency('gio-2.0'),
+  dependency('gobject-2.0'),
+]
+
+sources = [
+  config,
+  'ifaces.vala',
+  'device.vala',
+  'upower.vala',
+  'kbd.vala',
+  'profiles.vala',
+  'utils.vala',
+]
+
+if get_option('lib')
+  lib = library(
+    meson.project_name(),
+    sources,
+    dependencies: deps,
+    vala_header: meson.project_name() + '-' + api_version + '.h',
+    vala_vapi: meson.project_name() + '-' + api_version + '.vapi',
+    vala_gir: gir,
+    version: meson.project_version(),
+    install: true,
+    install_dir: [true, true, true, true],
+  )
+
+  import('pkgconfig').generate(
+    lib,
+    name: meson.project_name(),
+    filebase: meson.project_name() + '-' + api_version,
+    version: meson.project_version(),
+    subdirs: meson.project_name(),
+    requires: deps,
+    install_dir: get_option('libdir') / 'pkgconfig',
+  )
+
+  custom_target(
+    typelib,
+    command: [
+      find_program('g-ir-compiler'),
+      '--output', '@OUTPUT@',
+      '--shared-library', get_option('prefix') / get_option('libdir') / '@PLAINNAME@',
+      meson.current_build_dir() / gir,
+    ],
+    input: lib,
+    output: typelib,
+    depends: lib,
+    install: true,
+    install_dir: get_option('libdir') / 'girepository-1.0',
+  )
+endif
+
+if get_option('cli')
+  executable(
+    meson.project_name(),
+    ['cli.vala', sources],
+    dependencies: deps,
+    install: true,
+  )
+endif
diff --git a/src/profiles.vala b/src/profiles.vala
new file mode 100644
index 0000000..4b43923
--- /dev/null
+++ b/src/profiles.vala
@@ -0,0 +1,65 @@
+namespace AstalBattery {
+public PowerProfiles get_power_profiles() {
+    return PowerProfiles.get_default();
+}
+
+public class PowerProfiles : Object {
+    private static PowerProfiles instance;
+    public static PowerProfiles get_default() {
+        if (instance != null)
+            return instance;
+
+        instance = new PowerProfiles();
+        return instance;
+    }
+
+    private IPowerProfiles proxy;
+    private Properties props;
+
+    public string[] actions { owned get { return proxy.actions; } }
+    public string active_profile { owned get { return proxy.active_profile; } }
+    public HashTable<string, Variant>[] active_profile_holds { owned get { return proxy.active_profile_holds; } }
+    public string performance_degraded { owned get { return proxy.performance_degraded; } }
+    public string performance_inhibited { owned get { return proxy.performance_inhibited; } }
+    public HashTable<string, Variant>[] profiles { owned get { return proxy.profiles; } }
+    public string version { owned get { return proxy.version; } }
+
+    public signal uint profile_released (uint cookie);
+
+    public uint hold_profile(string profile, string reason, string application_id) throws Error {
+        return proxy.hold_profile(profile, reason, application_id);
+    }
+
+    public void release_profile(uint cookie) throws Error {
+        proxy.release_profile(cookie);
+    }
+
+    construct {
+        try {
+            proxy = Bus.get_proxy_sync(
+                BusType.SYSTEM,
+                "org.freedesktop.UPower.PowerProfiles",
+                "/org/freedesktop/UPower/PowerProfiles"
+            );
+
+            props = Bus.get_proxy_sync(
+                BusType.SYSTEM,
+                "org.freedesktop.UPower.PowerProfiles",
+                "/org/freedesktop/UPower/PowerProfiles"
+            );
+
+            props.properties_changed.connect((iface, vardict) => {
+                foreach (var key in vardict.get_keys()) {
+                    var prop = pascal_to_kebab_case(key);
+                    if (get_class().find_property(prop) != null)
+                        notify_property(prop);
+                }
+            });
+
+            proxy.profile_released.connect((cookie) => profile_released(cookie));
+        } catch (Error error) {
+            critical(error.message);
+        }
+    }
+}
+}
diff --git a/src/upower.vala b/src/upower.vala
new file mode 100644
index 0000000..9c18ffd
--- /dev/null
+++ b/src/upower.vala
@@ -0,0 +1,58 @@
+namespace AstalBattery {
+public class UPower : Object {
+    private IUPower proxy;
+    private HashTable<string, Device> _devices =
+        new HashTable<string, Device>(str_hash, str_equal);
+
+    public List<weak Device> devices {
+        owned get { return _devices.get_values(); }
+    }
+
+    public signal void device_added(Device device);
+    public signal void device_removed(Device device);
+
+    public Device display_device { owned get { return Device.get_default(); }}
+
+    public string daemon_version { owned get { return proxy.daemon_version; } }
+    public bool on_battery { get { return proxy.on_battery; } }
+    public bool lid_is_closed { get { return proxy.lid_is_closed; } }
+    public bool lis_is_present { get { return proxy.lid_is_closed; } }
+
+    public string critical_action {
+        owned get {
+            try {
+                return proxy.get_critical_action();
+            } catch (Error error) {
+                critical(error.message);
+                return "";
+            }
+        }
+    }
+
+    construct {
+        try {
+            proxy = Bus.get_proxy_sync(
+                BusType.SYSTEM,
+                "org.freedesktop.UPower",
+                "/org/freedesktop/UPower"
+            );
+
+            foreach (var path in proxy.enumerate_devices())
+                _devices.set(path, new Device(path));
+
+            proxy.device_added.connect((path) => {
+                _devices.set(path, new Device(path));
+                notify_property("devices");
+            });
+
+            proxy.device_removed.connect((path) => {
+                device_removed(_devices.get(path));
+                _devices.remove(path);
+                notify_property("devices");
+            });
+        } catch (Error error) {
+            critical(error.message);
+        }
+    }
+}
+}
diff --git a/src/utils.vala b/src/utils.vala
new file mode 100644
index 0000000..de22f18
--- /dev/null
+++ b/src/utils.vala
@@ -0,0 +1,36 @@
+namespace AstalBattery{
+internal string pascal_to_kebab_case(string pascal) {
+    StringBuilder kebab = new StringBuilder();
+
+    for (int i = 0; i < pascal.length; i++) {
+        char c = pascal[i];
+        if (c.isupper()) {
+            if (i != 0)
+                kebab.append_c('-');
+
+            kebab.append_c(c.tolower());
+        } else {
+            kebab.append_c(c);
+        }
+    }
+
+    return kebab.str;
+}
+
+internal string to_json(AstalBattery.Device device) {
+    string s = "unknown";
+    if (device.state == AstalBattery.DeviceState.CHARGING)
+        s = "charging";
+    if (device.state == AstalBattery.DeviceState.DISCHARGING)
+        s = "discharging";
+    if (device.state == AstalBattery.DeviceState.FULLY_CHARGED)
+        s = "fully_charged";
+
+    var p = device.percentage;
+    var i = device.icon_name;
+    var r = device.state == AstalBattery.DeviceState.CHARGING
+        ? device.time_to_full : device.time_to_empty;
+
+    return "{ \"percentage\": %f, \"state\": \"%s\", \"icon_name\": \"%s\", \"time_remaining\": %f }".printf(p, s, i, r);
+}
+}
diff --git a/version b/version
new file mode 100644
index 0000000..6e8bf73
--- /dev/null
+++ b/version
@@ -0,0 +1 @@
+0.1.0