command: split set-option into "toplevel" commands

`riverctl set-option view_padding 10` becomes `riverctl view-padding 10`

Having set-option doesn't really gain us anything and is more verbose as
well as being slightly inaccurate as the changes instantly apply.

river/command/config.zig

@@ -0,0 +1,116 @@
+// This file is part of river, a dynamic tiling wayland compositor.
+//
+// Copyright 2020 Isaac Freund
+//
+// 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/>.
+
+const std = @import("std");
+
+const Error = @import("../command.zig").Error;
+const Seat = @import("../Seat.zig");
+
+pub fn borderWidth(
+    allocator: *std.mem.Allocator,
+    seat: *Seat,
+    args: []const []const u8,
+    out: *?[]const u8,
+) Error!void {
+    if (args.len < 2) return Error.NotEnoughArguments;
+    if (args.len > 2) return Error.TooManyArguments;
+
+    const server = seat.input_manager.server;
+    server.config.border_width = try std.fmt.parseInt(u32, args[1], 10);
+    server.root.arrange();
+}
+
+pub fn viewPadding(
+    allocator: *std.mem.Allocator,
+    seat: *Seat,
+    args: []const []const u8,
+    out: *?[]const u8,
+) Error!void {
+    if (args.len < 2) return Error.NotEnoughArguments;
+    if (args.len > 2) return Error.TooManyArguments;
+
+    const server = seat.input_manager.server;
+    server.config.view_padding = try std.fmt.parseInt(u32, args[1], 10);
+    server.root.arrange();
+}
+
+pub fn outerPadding(
+    allocator: *std.mem.Allocator,
+    seat: *Seat,
+    args: []const []const u8,
+    out: *?[]const u8,
+) Error!void {
+    if (args.len < 2) return Error.NotEnoughArguments;
+    if (args.len > 2) return Error.TooManyArguments;
+
+    const server = seat.input_manager.server;
+    server.config.outer_padding = try std.fmt.parseInt(u32, args[1], 10);
+    server.root.arrange();
+}
+
+pub fn backgroundColor(
+    allocator: *std.mem.Allocator,
+    seat: *Seat,
+    args: []const []const u8,
+    out: *?[]const u8,
+) Error!void {
+    if (args.len < 2) return Error.NotEnoughArguments;
+    if (args.len > 2) return Error.TooManyArguments;
+
+    seat.input_manager.server.config.background_color = try parseRgba(args[1]);
+}
+
+pub fn borderColorFocused(
+    allocator: *std.mem.Allocator,
+    seat: *Seat,
+    args: []const []const u8,
+    out: *?[]const u8,
+) Error!void {
+    if (args.len < 2) return Error.NotEnoughArguments;
+    if (args.len > 2) return Error.TooManyArguments;
+
+    seat.input_manager.server.config.border_color_focused = try parseRgba(args[1]);
+}
+
+pub fn borderColorUnfocused(
+    allocator: *std.mem.Allocator,
+    seat: *Seat,
+    args: []const []const u8,
+    out: *?[]const u8,
+) Error!void {
+    if (args.len < 2) return Error.NotEnoughArguments;
+    if (args.len > 2) return Error.TooManyArguments;
+
+    seat.input_manager.server.config.border_color_unfocused = try parseRgba(args[1]);
+}
+
+/// Parse a color in the format #RRGGBB or #RRGGBBAA
+fn parseRgba(string: []const u8) ![4]f32 {
+    if (string[0] != '#' or (string.len != 7 and string.len != 9)) return error.InvalidRgba;
+
+    const r = try std.fmt.parseInt(u8, string[1..3], 16);
+    const g = try std.fmt.parseInt(u8, string[3..5], 16);
+    const b = try std.fmt.parseInt(u8, string[5..7], 16);
+    const a = if (string.len == 9) try std.fmt.parseInt(u8, string[7..9], 16) else 255;
+
+    return [4]f32{
+        @intToFloat(f32, r) / 255.0,
+        @intToFloat(f32, g) / 255.0,
+        @intToFloat(f32, b) / 255.0,
+        @intToFloat(f32, a) / 255.0,
+    };
+}