package simulator

import emu "../machine"
import rl "vendor:raylib"

// @ Window
WINDOW_WIDTH  :: 1920
WINDOW_HEIGHT :: 1080

// @ Layout proportions
// Sidebar takes 20% of screen width on each side; display takes the rest.
// The center column splits vertically: 40% display, 60% debug panel.
SIDEBAR_PERCENT		:: f32(0.20)
DISPLAY_V_RATIO		:: f32(0.40)
// @ Fixed heights
CONTROL_BAR_H		:: f32(50)
STATUS_BAR_H		:: f32(30)
// @ Layout constants
PADDING_X			:: f32(10)
PADDING_Y			:: f32(8)
PANEL_HEADER		:: f32(24)
// @ Buttons
BUTTON_HEIGHT		:: 30
BUTTON_WIDTH		:: 120
// @ Fonts
BIG_FONT_SIZE		:: 20
KEYPAD_FONT_SIZE	:: 18

Layout :: struct {
	control_bar  : rl.Rectangle,
	file_loader  : rl.Rectangle,
	keypad       : rl.Rectangle,
	display		 : rl.Rectangle,
	bottom_panel : rl.Rectangle,
	cpu			 : rl.Rectangle,
	status_bar   : rl.Rectangle,
}

// Initialize main the gui 'window'
run_gui :: proc(sim: ^Simulator) {
    rl.SetConfigFlags({.WINDOW_RESIZABLE})
    rl.InitWindow(WINDOW_WIDTH, WINDOW_HEIGHT, "raylib")
    rl.InitAudioDevice()
    rl.SetTargetFPS(60)
    beep := rl.LoadSound("./assets/sounds/beep.wav")

    // Load fonts
    font := rl.LoadFontEx("./assets/fonts/Inter_18pt-Regular.ttf", 18, nil, 0)
    rl.SetTextureFilter(font.texture, .BILINEAR)
    sim.font = font

    rl.GuiLoadStyleDefault()
    rl.GuiLoadStyle("./assets/raygui_styles/style_dark.rgs")

    rl.GuiSetFont(font)
    rl.GuiSetStyle(.DEFAULT, i32(rl.GuiDefaultProperty.TEXT_SIZE), 18)

	// Draw each of the components in its own window within the main window
	for !rl.WindowShouldClose() {
		// Recalculate layout each frame based on current window size
		// Pass these down to gui functions so they can setup their sizes?
		screen_width  := f32(rl.GetScreenWidth())
		screen_height := f32(rl.GetScreenHeight())
		sidebar_width := screen_width * 0.20

		// set all the layout structs dynamically with the screen size
		layout := calc_layout(screen_width, screen_height)

		rl.BeginDrawing()
		rl.ClearBackground(rl.BLACK)

		if (!sim.paused) {
			// Cycle the machine to update memory etc
			emu.run_machine(sim.machine, 12)

			// Handle delay timer
			if sim.machine.delay_timer > 0 do sim.machine.delay_timer -= 1

			// Current sound file is around 1s so stop
			// immediately when timer is 0
			if sim.machine.sound_timer > 0 {
				sim.machine.sound_timer -= 1
				if !rl.IsSoundPlaying(beep) do rl.PlaySound(beep)
			} else {
				rl.StopSound(beep)
			}
		}

		// Top
		// ------------------------------------------
		gui_control_bar(layout.control_bar, sim)

		// Left
		// ------------------------------------------
		gui_file_loader(layout.file_loader, sim)
		gui_key_pad(layout.keypad, sim.machine.keypad, sim.font)

		// Center
		// ------------------------------------------
		gui_screen(layout.display, sim)

		// Right
		// ------------------------------------------
		gui_cpu(layout.cpu, sim)

		// Bottom
		// ------------------------------------------
		gui_bottom_tabs(layout.bottom_panel, sim)
		gui_status_bar(layout.status_bar, sim)

		rl.EndDrawing()
	}

	rl.UnloadFont(sim.font)
	rl.UnloadSound(beep)
	rl.CloseAudioDevice()
	rl.CloseWindow()
}

// @TODO: If this grows lets move it into its own file
calc_layout :: proc(screen_width: f32, screen_height: f32) -> Layout {
	// Control bar is a fixed height frozen at top of gui, all items start below it.
	y_pos			   := CONTROL_BAR_H
	x_pos			   := f32(0)

	// Usable gui vertical space
	visible_height	   := screen_height - CONTROL_BAR_H - STATUS_BAR_H
	sidebar_width	   := screen_width * SIDEBAR_PERCENT
	display_width	   := screen_width - (sidebar_width * 2) - sidebar_width
	display_height	   := visible_height * DISPLAY_V_RATIO

	x_center		   := sidebar_width
	y_center		   := screen_width - sidebar_width * 2

	return Layout {
		// Left Area
		control_bar = rl.Rectangle{
			x = 0,
			y = 0,
			width = screen_width,
			height = CONTROL_BAR_H,
		},
		file_loader = rl.Rectangle{
			x = 0,
			y = y_pos,
			width = sidebar_width,
			height = visible_height / 3
		},
		keypad = rl.Rectangle{
			x = 0,
			y = (y_pos + visible_height - visible_height / 2),
			width = sidebar_width,
			height = visible_height / 2
		},

		// ------------------------------------------
		// Center Area
		display = rl.Rectangle{
			x = sidebar_width,
			y = y_pos,
			width = display_width,
			height = display_height,
		},

		// ------------------------------------------
		// Bottom Area
		bottom_panel = rl.Rectangle{
			x = sidebar_width,
			y = y_pos + display_height,
			width = screen_width - sidebar_width,
			height = visible_height - display_height,
		},

		// ------------------------------------------
		// Right Area
		cpu = rl.Rectangle {
			x = sidebar_width + display_width,
			y = y_pos,
			width = sidebar_width * 2,
			height = display_height
		},

		// ------------------------------------------
		// Bottom Area
		status_bar = rl.Rectangle{
			x = x_pos,
			y = y_pos + visible_height,
			width = screen_width,
			height = STATUS_BAR_H,
		},
	}
}