zterm/src/input.zig

//! Input module for `zterm`. Contains structs to represent key events and mouse events.
const std = @import("std");

const Point = @import("point.zig").Point;

pub const Mouse = packed struct {
    x: u16,
    y: u16,
    button: Button,
    kind: Kind,

    pub const Button = enum(u8) {
        left,
        middle,
        right,
        none,
        wheel_up = 64,
        wheel_down = 65,
        wheel_right = 66,
        wheel_left = 67,
        button_8 = 128,
        button_9 = 129,
        button_10 = 130,
        button_11 = 131,
    };

    pub const Kind = enum(u2) {
        press,
        release,
        motion,
        drag,
    };

    pub fn eql(this: @This(), other: @This()) bool {
        return std.meta.eql(this, other);
    }

    pub fn in(this: @This(), origin: Point, size: Point) bool {
        return this.x >= origin.x and this.x < size.x + origin.x and
            this.y >= origin.y and this.y < size.y + origin.y;
    }
};

pub const Key = packed struct {
    cp: u21,
    mod: Modifier = .{},

    pub const Modifier = packed struct {
        shift: bool = false,
        alt: bool = false,
        ctrl: bool = false,
    };

    /// Compare _this_ `Key` with an _other_ `Key`.
    ///
    /// # Example
    ///
    /// Configure `ctrl+c` to quit the application (done in main event loop of the application):
    ///
    /// ```zig
    /// switch (event) {
    ///     .quit => break,
    ///     .key => |key| if (key.eql(.{ .cp = 'c', .mod = .{ .ctrl = true } })) app.quit.set(),
    ///     else => {},
    /// }
    /// ```
    pub fn eql(this: @This(), other: @This()) bool {
        return std.meta.eql(this, other);
    }

    /// Determine if the `Key` is an ascii character that can be printed to
    /// the screen. This means that the code point of the `Key` is an ascii
    /// character between 32 - 255 (with the exception of 127 = Delete) and no
    /// modifiers (alt and/or ctrl) are used.
    ///
    /// # Example
    ///
    /// Get user input's from the .key event from the application event loop:
    ///
    /// ```zig
    /// switch (event) {
    ///   .key => |key| if (key.isAscii()) try this.input.append(key.cp),
    ///   else => {},
    /// }
    /// ```
    pub fn isAscii(this: @This()) bool {
        return this.mod.alt == false and this.mod.ctrl == false and // no modifier keys
            (this.cp >= 32 and this.cp <= 126 or // ascii printable characters (except for input.Delete)
                this.cp >= 128 and this.cp <= 255); // extended ascii codes
    }

    test "isAscii with ascii character" {
        try std.testing.expectEqual(true, isAscii(.{ .cp = 'c' }));
        try std.testing.expectEqual(false, isAscii(.{ .cp = 'c', .mod = .{ .ctrl = true } }));
        try std.testing.expectEqual(false, isAscii(.{ .cp = 'c', .mod = .{ .alt = true } }));
        try std.testing.expectEqual(false, isAscii(.{ .cp = 'c', .mod = .{ .alt = true, .ctrl = true } }));
    }

    test "isAscii with non-ascii character" {
        try std.testing.expectEqual(false, isAscii(.{ .cp = Escape }));
        try std.testing.expectEqual(false, isAscii(.{ .cp = Enter }));
        try std.testing.expectEqual(false, isAscii(.{ .cp = Enter, .mod = .{ .alt = true } }));
    }

    test "isAscii with excluded input.Delete" {
        try std.testing.expectEqual(false, isAscii(.{ .cp = Delete }));
        try std.testing.expectEqual(false, isAscii(.{ .cp = Delete, .mod = .{ .alt = false, .ctrl = false } }));
    }
};

// codepoints for keys
pub const Tab: u21 = 0x09;
pub const Enter: u21 = 0x0D;
pub const Escape: u21 = 0x1B;
pub const Space: u21 = 0x20;
pub const Backspace: u21 = 0x7F;

// kitty key encodings (re-used here)
pub const Insert: u21 = 57348;
pub const Delete: u21 = 57349;
pub const Left: u21 = 57350;
pub const Right: u21 = 57351;
pub const Up: u21 = 57352;
pub const Down: u21 = 57353;
pub const PageUp: u21 = 57354;
pub const PageDown: u21 = 57355;
pub const Home: u21 = 57356;
pub const End: u21 = 57357;
pub const CapsLock: u21 = 57358;
pub const ScrollLock: u21 = 57359;
pub const NumLock: u21 = 57360;
pub const PrintScreen: u21 = 57361;
pub const Pause: u21 = 57362;
pub const Menu: u21 = 57363;
pub const F1: u21 = 57364;
pub const F2: u21 = 57365;
pub const F3: u21 = 57366;
pub const F4: u21 = 57367;
pub const F5: u21 = 57368;
pub const F6: u21 = 57369;
pub const F7: u21 = 57370;
pub const F8: u21 = 57371;
pub const F9: u21 = 57372;
pub const F10: u21 = 57373;
pub const F11: u21 = 57374;
pub const F12: u21 = 57375;
pub const F13: u21 = 57376;
pub const F14: u21 = 57377;
pub const F15: u21 = 57378;
pub const F16: u21 = 57379;
pub const F17: u21 = 57380;
pub const F18: u21 = 57381;
pub const F19: u21 = 57382;
pub const F20: u21 = 57383;
pub const F21: u21 = 57384;
pub const F22: u21 = 57385;
pub const F23: u21 = 57386;
pub const F24: u21 = 57387;
pub const F25: u21 = 57388;
pub const F26: u21 = 57389;
pub const F27: u21 = 57390;
pub const F28: u21 = 57391;
pub const F29: u21 = 57392;
pub const F30: u21 = 57393;
pub const F31: u21 = 57394;
pub const F32: u21 = 57395;
pub const F33: u21 = 57396;
pub const F34: u21 = 57397;
pub const F35: u21 = 57398;
pub const Kp0: u21 = 57399;
pub const Kp1: u21 = 57400;
pub const Kp2: u21 = 57401;
pub const Kp3: u21 = 57402;
pub const Kp4: u21 = 57403;
pub const Kp5: u21 = 57404;
pub const Kp6: u21 = 57405;
pub const Kp7: u21 = 57406;
pub const Kp8: u21 = 57407;
pub const Kp9: u21 = 57408;
pub const KpDecimal: u21 = 57409;
pub const KpDivide: u21 = 57410;
pub const KpMultiply: u21 = 57411;
pub const KpSubtract: u21 = 57412;
pub const KpAdd: u21 = 57413;
pub const KpEnter: u21 = 57414;
pub const KpEqual: u21 = 57415;
pub const KpSeparator: u21 = 57416;
pub const KpLeft: u21 = 57417;
pub const KpRight: u21 = 57418;
pub const KpUp: u21 = 57419;
pub const KpDown: u21 = 57420;
pub const KpPageUp: u21 = 57421;
pub const KpPageDown: u21 = 57422;
pub const KpHome: u21 = 57423;
pub const KpEnd: u21 = 57424;
pub const KpInsert: u21 = 57425;
pub const KpDelete: u21 = 57426;
pub const KpBegin: u21 = 57427;
pub const MediaPlay: u21 = 57428;
pub const MediaPause: u21 = 57429;
pub const MediaPlayPause: u21 = 57430;
pub const MediaReverse: u21 = 57431;
pub const MediaStop: u21 = 57432;
pub const MediaFastForward: u21 = 57433;
pub const MediaRewind: u21 = 57434;
pub const MediaTrackNext: u21 = 57435;
pub const MediaTrackPrevious: u21 = 57436;
pub const MediaRecord: u21 = 57437;
pub const LowerVolume: u21 = 57438;
pub const RaiseVolume: u21 = 57439;
pub const MuteVolume: u21 = 57440;
pub const LeftShift: u21 = 57441;
pub const LeftControl: u21 = 57442;
pub const LeftAlt: u21 = 57443;
pub const LeftSuper: u21 = 57444;
pub const LeftHyper: u21 = 57445;
pub const LeftMeta: u21 = 57446;
pub const RightShift: u21 = 57447;
pub const RightControl: u21 = 57448;
pub const RightAlt: u21 = 57449;
pub const RightSuper: u21 = 57450;
pub const RightHyper: u21 = 57451;
pub const RightMeta: u21 = 57452;
pub const IsoLevel3Shift: u21 = 57453;
pub const IsoLevel5Shift: u21 = 57454;