const std = @import("std");
const assert = std.debug.assert;
const sokol = @import("sokol");

const lib = @import("lib");
const Frame = lib.Frame;
const Nanoseconds = lib.Nanoseconds;
const Vec2 = lib.Math.Vec2;

const Input = @This();

pub const Event = union(enum) {
    mouse_pressed: struct {
        button: lib.MouseButton,
        position: Vec2,
    },
    mouse_released: struct {
        button: lib.MouseButton,
        position: Vec2,
    },
    mouse_move: Vec2,
    mouse_enter: Vec2,
    mouse_leave,
    mouse_scroll: Vec2,
    key_pressed: struct {
        code: lib.KeyCode,
        repeat: bool
    },
    key_released: lib.KeyCode,
    window_resize,
    char: u21,
};

mouse_position: ?Vec2,

pub const initial = Input{
    .mouse_position = null
};

pub fn processEvent(self: *Input, frame: *Frame, event: Event) void {
    switch (event) {
        .key_pressed => |opts| {
            if (!opts.repeat) {
                frame.keyboard.press(opts.code, frame.time_ns);
            }
        },
        .key_released => |key_code| {
            frame.keyboard.release(key_code);
        },
        .mouse_leave => {
            frame.keyboard.releaseAll();

            assert(self.mouse_position != null);
            self.mouse_position = null;
            frame.mouse_button = .empty;
        },
        .mouse_enter => |pos| {
            assert(self.mouse_position == null);
            self.mouse_position = pos;
        },
        .mouse_move => |pos| {
            assert(self.mouse_position != null);
            self.mouse_position = pos;
        },
        .mouse_pressed => |opts| {
            assert(self.mouse_position != null);
            self.mouse_position = opts.position;
            frame.mouse_button.press(opts.button, frame.time_ns);
        },
        .mouse_released => |opts| {
            assert(self.mouse_position != null);
            self.mouse_position = opts.position;
            frame.mouse_button.release(opts.button);
        },
        else => {}
    }
}

pub fn getKeyCodeFromSokol(key_code: sokol.app.Keycode) ?lib.KeyCode {
    return switch (key_code) {
        .SPACE => .SPACE,
        .APOSTROPHE => .APOSTROPHE,
        .COMMA => .COMMA,
        .MINUS => .MINUS,
        .PERIOD => .PERIOD,
        .SLASH => .SLASH,
        ._0 => ._0,
        ._1 => ._1,
        ._2 => ._2,
        ._3 => ._3,
        ._4 => ._4,
        ._5 => ._5,
        ._6 => ._6,
        ._7 => ._7,
        ._8 => ._8,
        ._9 => ._9,
        .SEMICOLON => .SEMICOLON,
        .EQUAL => .EQUAL,
        .A => .A,
        .B => .B,
        .C => .C,
        .D => .D,
        .E => .E,
        .F => .F,
        .G => .G,
        .H => .H,
        .I => .I,
        .J => .J,
        .K => .K,
        .L => .L,
        .M => .M,
        .N => .N,
        .O => .O,
        .P => .P,
        .Q => .Q,
        .R => .R,
        .S => .S,
        .T => .T,
        .U => .U,
        .V => .V,
        .W => .W,
        .X => .X,
        .Y => .Y,
        .Z => .Z,
        .LEFT_BRACKET => .LEFT_BRACKET,
        .BACKSLASH => .BACKSLASH,
        .RIGHT_BRACKET => .RIGHT_BRACKET,
        .GRAVE_ACCENT => .GRAVE_ACCENT,
        .WORLD_1 => .WORLD_1,
        .WORLD_2 => .WORLD_2,
        .ESCAPE => .ESCAPE,
        .ENTER => .ENTER,
        .TAB => .TAB,
        .BACKSPACE => .BACKSPACE,
        .INSERT => .INSERT,
        .DELETE => .DELETE,
        .RIGHT => .RIGHT,
        .LEFT => .LEFT,
        .DOWN => .DOWN,
        .UP => .UP,
        .PAGE_UP => .PAGE_UP,
        .PAGE_DOWN => .PAGE_DOWN,
        .HOME => .HOME,
        .END => .END,
        .CAPS_LOCK => .CAPS_LOCK,
        .SCROLL_LOCK => .SCROLL_LOCK,
        .NUM_LOCK => .NUM_LOCK,
        .PRINT_SCREEN => .PRINT_SCREEN,
        .PAUSE => .PAUSE,
        .F1 => .F1,
        .F2 => .F2,
        .F3 => .F3,
        .F4 => .F4,
        .F5 => .F5,
        .F6 => .F6,
        .F7 => .F7,
        .F8 => .F8,
        .F9 => .F9,
        .F10 => .F10,
        .F11 => .F11,
        .F12 => .F12,
        .F13 => .F13,
        .F14 => .F14,
        .F15 => .F15,
        .F16 => .F16,
        .F17 => .F17,
        .F18 => .F18,
        .F19 => .F19,
        .F20 => .F20,
        .F21 => .F21,
        .F22 => .F22,
        .F23 => .F23,
        .F24 => .F24,
        .F25 => .F25,
        .KP_0 => .KP_0,
        .KP_1 => .KP_1,
        .KP_2 => .KP_2,
        .KP_3 => .KP_3,
        .KP_4 => .KP_4,
        .KP_5 => .KP_5,
        .KP_6 => .KP_6,
        .KP_7 => .KP_7,
        .KP_8 => .KP_8,
        .KP_9 => .KP_9,
        .KP_DECIMAL => .KP_DECIMAL,
        .KP_DIVIDE => .KP_DIVIDE,
        .KP_MULTIPLY => .KP_MULTIPLY,
        .KP_SUBTRACT => .KP_SUBTRACT,
        .KP_ADD => .KP_ADD,
        .KP_ENTER => .KP_ENTER,
        .KP_EQUAL => .KP_EQUAL,
        .LEFT_SHIFT => .LEFT_SHIFT,
        .LEFT_CONTROL => .LEFT_CONTROL,
        .LEFT_ALT => .LEFT_ALT,
        .LEFT_SUPER => .LEFT_SUPER,
        .RIGHT_SHIFT => .RIGHT_SHIFT,
        .RIGHT_CONTROL => .RIGHT_CONTROL,
        .RIGHT_ALT => .RIGHT_ALT,
        .RIGHT_SUPER => .RIGHT_SUPER,
        .MENU => .MENU,
        else => null
    };
}

pub fn getMouseButtonFromSokol(mouse_button: sokol.app.Mousebutton) ?lib.MouseButton {
    return switch (mouse_button) {
        .RIGHT => .right,
        .MIDDLE => .middle,
        .LEFT => .left,
        else => null
    };
}