1 files changed, 31 insertions, 9 deletions

diff --git a/rules.js b/rules.js
index b004507..2b6bd72 100644
--- a/rules.js
+++ b/rules.js
@@ -17,7 +17,7 @@ var timeout = 0
 
 function check_timeout() {
 	if (Date.now() > timeout)
-		throw new Error("timeout (too many withdrawal options)")
+		throw "TIMEOUT"
 }
 
 var states = {}
@@ -3241,9 +3241,15 @@ function goto_move_phase() {
 			game.rommel = 1
 
 	if (game.turn_option === 'pass') {
-		save_withdrawal_supply_lines()
-		game.group = list_valid_withdrawal_group_moves()
-		game.regroup = list_valid_withdrawal_regroup_command_points()
+		try {
+			save_withdrawal_supply_lines()
+			game.group = list_valid_withdrawal_group_moves()
+			game.regroup = list_valid_withdrawal_regroup_command_points()
+		} catch (err) {
+			if (err !== "TIMEOUT")
+				throw err
+			game.state = 'select_moves_timeout'
+		}
 	} else {
 		game.group = list_valid_group_moves()
 		game.regroup = list_valid_regroup_moves()
@@ -3258,6 +3264,8 @@ function show_move_commands() {
 }
 
 function has_valid_group_move_left() {
+	if (!game.group)
+		return false
 	if (game.group.length > 1)
 		return true
 	if (game.group.length > 0) {
@@ -3293,6 +3301,13 @@ states.select_moves = {
 			view.prompt = `Movement: Designate ${game.turn_option} move.`
 		}
 
+		if (game.state === 'select_moves_timeout') {
+			if (game.group && !game.regroup)
+				view.prompt = "Movement: Computation timed out. Regroup moves not available."
+			else
+				view.prompt = "Movement: Computation timed out. Some moves may not be available."
+		}
+
 		let can_group_move = has_valid_group_move_left() ? 1 : 0
 		let can_regroup_move = has_valid_regroup_move_left() ? 1 : 0
 
@@ -3347,6 +3362,8 @@ states.select_moves = {
 	},
 }
 
+states.select_moves_timeout = states.select_moves
+
 function list_valid_group_moves() {
 	let result = []
 	for (let x of all_hexes) {
@@ -3375,13 +3392,18 @@ function list_valid_withdrawal_group_moves() {
 		set_add(result, TOBRUK)
 		mandatory = true
 	}
-	if (!mandatory) {
-		for (let x of all_hexes) {
-			if (has_undisrupted_friendly_unit(x)) {
-				if (is_valid_withdrawal_group_move_from(x))
-					set_add(result, x)
+	try {
+		if (!mandatory) {
+			for (let x of all_hexes) {
+				if (has_undisrupted_friendly_unit(x)) {
+					if (is_valid_withdrawal_group_move_from(x))
+						set_add(result, x)
+				}
 			}
 		}
+	} catch (err) {
+		if (err !== "TIMEOUT")
+			throw err
 	}
 	return result
 }