// Copyright (c) 2020-2021 Raúl Hernández. All rights reserved.
// Use of this source code is governed by an MIT license
// that can be found in the LICENSE file.
module ui

import os

pub enum KeyCode {
	null                 = 0
	tab                  = 9
	enter                = 10
	escape               = 27
	space                = 32
	backspace            = 127
	exclamation          = 33
	double_quote         = 34
	hashtag              = 35
	dollar               = 36
	percent              = 37
	ampersand            = 38
	single_quote         = 39
	left_paren           = 40
	right_paren          = 41
	asterisk             = 42
	plus                 = 43
	comma                = 44
	minus                = 45
	period               = 46
	slash                = 47
	_0                   = 48
	_1                   = 49
	_2                   = 50
	_3                   = 51
	_4                   = 52
	_5                   = 53
	_6                   = 54
	_7                   = 55
	_8                   = 56
	_9                   = 57
	colon                = 58
	semicolon            = 59
	less_than            = 60
	equal                = 61
	greater_than         = 62
	question_mark        = 63
	at                   = 64
	a                    = 97
	b                    = 98
	c                    = 99
	d                    = 100
	e                    = 101
	f                    = 102
	g                    = 103
	h                    = 104
	i                    = 105
	j                    = 106
	k                    = 107
	l                    = 108
	m                    = 109
	n                    = 110
	o                    = 111
	p                    = 112
	q                    = 113
	r                    = 114
	s                    = 115
	t                    = 116
	u                    = 117
	v                    = 118
	w                    = 119
	x                    = 120
	y                    = 121
	z                    = 122
	left_square_bracket  = 91
	backslash            = 92
	right_square_bracket = 93
	caret                = 94
	underscore           = 95
	backtick             = 96
	left_curly_bracket   = 123
	vertical_bar         = 124
	right_curly_bracket  = 125
	tilde                = 126
	insert               = 260
	delete               = 261
	up                   = 262
	down                 = 263
	right                = 264
	left                 = 265
	page_up              = 266
	page_down            = 267
	home                 = 268
	end                  = 269
	f1                   = 290
	f2                   = 291
	f3                   = 292
	f4                   = 293
	f5                   = 294
	f6                   = 295
	f7                   = 296
	f8                   = 297
	f9                   = 298
	f10                  = 299
	f11                  = 300
	f12                  = 301
	f13                  = 302
	f14                  = 303
	f15                  = 304
	f16                  = 305
	f17                  = 306
	f18                  = 307
	f19                  = 308
	f20                  = 309
	f21                  = 310
	f22                  = 311
	f23                  = 312
	f24                  = 313
}

pub enum Direction {
	unknown
	up
	down
	left
	right
}

pub enum MouseButton {
	unknown
	left
	middle
	right
}

pub enum EventType {
	unknown
	mouse_down
	mouse_up
	mouse_move
	mouse_drag
	mouse_scroll
	key_down
	resized
}

[flag]
pub enum Modifiers {
	ctrl
	shift
	alt
}

pub struct Event {
pub:
	typ EventType
	// Mouse event info
	x         int
	y         int
	button    MouseButton
	direction Direction
	// Keyboard event info
	code      KeyCode
	modifiers Modifiers
	ascii     u8
	utf8      string
	// Resized event info
	width  int
	height int
}

pub struct Context {
	ExtraContext // contains fields specific to an implementation
pub:
	cfg Config // the initial configuration, passed to ui.init()
mut:
	print_buf  []u8
	paused     bool
	enable_su  bool
	enable_rgb bool
pub mut:
	frame_count   u64
	window_width  int
	window_height int
}

pub struct Config {
	user_data  voidptr
	init_fn    ?fn (voidptr)
	frame_fn   ?fn (voidptr)
	cleanup_fn ?fn (voidptr)
	event_fn   ?fn (&Event, voidptr)
	fail_fn    ?fn (string)

	buffer_size int = 256
	frame_rate  int = 30
	use_x11     bool

	window_title         string
	hide_cursor          bool
	capture_events       bool
	use_alternate_buffer bool = true
	skip_init_checks     bool
	// All kill signals to set up exit listeners on:
	reset []os.Signal = [.hup, .int, .quit, .ill, .abrt, .bus, .fpe, .kill, .segv, .pipe, .alrm, .term,
	.stop]
}

[inline]
fn (ctx &Context) init() {
	f := ctx.cfg.init_fn or { return }
	f(ctx.cfg.user_data)
}

[inline]
fn (ctx &Context) frame() {
	f := ctx.cfg.frame_fn or { return }
	f(ctx.cfg.user_data)
}

[inline]
fn (ctx &Context) cleanup() {
	f := ctx.cfg.cleanup_fn or { return }
	f(ctx.cfg.user_data)
}

[inline]
fn (ctx &Context) fail(error string) {
	f := ctx.cfg.fail_fn or { return }
	f(error)
}

[inline]
fn (ctx &Context) event(event &Event) {
	f := ctx.cfg.event_fn or { return }
	f(event, ctx.cfg.user_data)
}
