add main menu

www/js/MenuFrontEnd.js

@@ -0,0 +1,51 @@
+let menu_start_game_button = document.getElementById("StartGameButton")
+let menu_start_time = document.getElementById("MenuStartTime")
+let menu_start_move_left = document.getElementById("MenuStartMoveLeft")
+let menu_block_time = document.getElementById("MenuBlockTime")
+let menu_max_increment = document.getElementById("MenuMaxIncrement")
+let menu_last_block = document.getElementById("MenuLastBlock")
+
+function clamp_number(value, fallback = 0) {
+    const parsed = Number(value)
+    if (Number.isNaN(parsed) || parsed < 0) return fallback
+    return parsed
+}
+
+function ms_to_minutes(ms) {
+    return Math.max(0, Math.round(ms / 60000))
+}
+
+function seconds_to_ms(seconds) {
+    return clamp_number(seconds) * 1000
+}
+
+function minutes_to_ms(minutes) {
+    return clamp_number(minutes) * 60000
+}
+
+function sync_menu_with_config() {
+    menu_start_time.value = ms_to_minutes(config.StartTimeWhite)
+    menu_start_move_left.value = clamp_number(config.StartMoveLeft)
+    menu_block_time.value = ms_to_minutes(config.BlockTime)
+    menu_max_increment.value = Math.round(clamp_number(config.MaxIncrement) / 1000)
+    menu_last_block.value = String(config.last_block)
+}
+
+function apply_menu_settings_to_config() {
+    config.StartTimeWhite = minutes_to_ms(menu_start_time.value)
+    config.StartTimeBlack = minutes_to_ms(menu_start_time.value)
+    config.StartMoveLeft = clamp_number(menu_start_move_left.value)
+    config.BlockTime = minutes_to_ms(menu_block_time.value)
+    config.MaxIncrement = seconds_to_ms(menu_max_increment.value)
+    config.last_block = menu_last_block.value === "true"
+}
+
+function on_menu_start_game_press() {
+    apply_menu_settings_to_config()
+    hide_scene("Menu")
+    load_Clock_scene()
+}
+
+menu_start_game_button.addEventListener("click", () => {
+    on_menu_start_game_press()
+})