feat: allow user to undo card movements

build.zig.zon

@@ -16,8 +16,8 @@
     // internet connectivity.
     .dependencies = .{
         .seizer = .{
-            .url = "https://github.com/leroycep/seizer/archive/d425db26fbbf5a99faa70ea07fb7d2b028f690d1.tar.gz",
+            .url = "https://github.com/leroycep/seizer/archive/2be76fb909fc487da4983a487d0695fc749f714a.tar.gz",
-            .hash = "1220250791e125cf4d342020eb3af65c36a8b971559ae9ffafc187c0cb116ee3d6e2",
+            .hash = "12207072224809e8a8d2c1342b5e14db5b6fbb1fbbd7f5c6410d71d3708c9241261e",
         },
     },
     .paths = .{

src/assets.zig

@@ -385,7 +385,7 @@ pub fn loadSolitaireCards(gpa: std.mem.Allocator) !DeckSprites {
         .blank = 13,
         .back = 27,
         .margin = 4,
-        .hand_offset = .{ 13, 12 },
+        .hand_offset = .{ 10, 12 },
     };
 }
 

src/main.zig

@@ -2,6 +2,7 @@ pub const main = seizer.main;
 
 var gpa: std.mem.Allocator = undefined;
 var prng: std.rand.DefaultPrng = undefined;
+var window_global: *seizer.Window = undefined;
 var canvas: seizer.Canvas = undefined;
 var card_tilemap: ?DeckSprites = null;
 
@@ -11,6 +12,8 @@ var drawn_cards: std.ArrayListUnmanaged(Card) = .{};
 var stacks: [7]std.ArrayListUnmanaged(Card) = [_]std.ArrayListUnmanaged(Card){.{}} ** 7;
 var foundations: [4]std.ArrayListUnmanaged(Card) = [_]std.ArrayListUnmanaged(Card){.{}} ** 4;
 
+var history: std.ArrayListUnmanaged(Snapshot) = .{};
+
 var last_hovered_stack: usize = 0;
 var last_hovered_foundation: usize = 0;
 var hovered_deck: ?*std.ArrayListUnmanaged(Card) = null;
@@ -19,11 +22,24 @@ var hovered_card: usize = 0;
 var selected_deck: ?*std.ArrayListUnmanaged(Card) = null;
 var selected_card: usize = 0;
 
+var show_menu: bool = false;
+var menu_item_selected: u32 = 0;
+const MENU_ITEMS = [_][]const u8{
+    "Continue",
+    "New Game",
+    "Quit",
+};
+
+var app_data_dir: std.fs.Dir = undefined;
+var win_count_file: std.fs.File = undefined;
+var win_count: u32 = 0;
+var win_triggered: bool = false;
+
 pub fn init(context: *seizer.Context) !void {
     gpa = context.gpa;
     prng = std.rand.DefaultPrng.init(@bitCast(std.time.timestamp()));
 
-    _ = try context.createWindow(.{
+    window_global = try context.createWindow(.{
         .title = "Seizer Solitaire",
         .on_render = render,
         .on_destroy = destroy,
@@ -34,15 +50,7 @@ pub fn init(context: *seizer.Context) !void {
 
     card_tilemap = try assets.loadSolitaireCards(context.gpa);
 
-    draw_pile = std.ArrayListUnmanaged(Card).fromOwnedSlice(try makeStandardDeck(gpa));
+    try resetGame();
-    prng.random().shuffle(Card, draw_pile.items);
-
-    for (&stacks, 0..) |*stack, i| {
-        for (0..i + 1) |_| {
-            const drawn_card = draw_pile.pop();
-            try stack.append(gpa, drawn_card);
-        }
-    }
 
     try context.addButtonInput(.{
         .title = "move_up",
@@ -74,6 +82,71 @@ pub fn init(context: *seizer.Context) !void {
         .on_event = deselect,
         .default_bindings = &.{.b},
     });
+    try context.addButtonInput(.{
+        .title = "toggle_menu",
+        .on_event = toggleMenu,
+        .default_bindings = &.{.start},
+    });
+    try context.addButtonInput(.{
+        .title = "undo",
+        .on_event = undo,
+        .default_bindings = &.{.x},
+    });
+
+    const app_data_dir_path = try std.fs.getAppDataDir(gpa, "seizer-solitaire");
+    defer gpa.free(app_data_dir_path);
+
+    app_data_dir = try std.fs.cwd().makeOpenPath(app_data_dir_path, .{});
+    win_count_file = try app_data_dir.createFile("win_count.bin", .{ .read = true, .truncate = false });
+
+    var win_count_buffer: [4]u8 = undefined;
+    const bytes_read = try win_count_file.preadAll(&win_count_buffer, 0);
+    if (bytes_read < win_count_buffer.len) {
+        win_count = 0;
+        std.mem.writeInt(u32, &win_count_buffer, win_count, .little);
+        try win_count_file.pwriteAll(&win_count_buffer, 0);
+    } else {
+        win_count = std.mem.readInt(u32, &win_count_buffer, .little);
+    }
+}
+
+fn resetGame() !void {
+    draw_pile.deinit(gpa);
+    draw_pile_exhausted = false;
+    drawn_cards.shrinkRetainingCapacity(0);
+    for (&stacks) |*stack| {
+        stack.shrinkRetainingCapacity(0);
+    }
+    for (&foundations) |*foundation| {
+        foundation.shrinkRetainingCapacity(0);
+    }
+
+    last_hovered_stack = 0;
+    last_hovered_foundation = 0;
+    hovered_deck = null;
+    hovered_card = 0;
+
+    selected_deck = null;
+    selected_card = 0;
+
+    draw_pile = std.ArrayListUnmanaged(Card).fromOwnedSlice(try makeStandardDeck(gpa));
+    prng.random().shuffle(Card, draw_pile.items);
+
+    for (&stacks, 0..) |*stack, i| {
+        for (0..i + 1) |_| {
+            const drawn_card = draw_pile.pop();
+            try stack.append(gpa, drawn_card);
+        }
+    }
+
+    win_triggered = false;
+}
+
+fn resetHistory() void {
+    for (history.items) |*snapshot| {
+        snapshot.deinit();
+    }
+    history.shrinkRetainingCapacity(0);
 }
 
 fn destroy(window: *seizer.Window) void {
@@ -95,6 +168,17 @@ fn destroy(window: *seizer.Window) void {
 }
 
 fn render(window: *seizer.Window) !void {
+    if (haveWon() and !win_triggered) {
+        win_count += 1;
+
+        var win_count_buffer: [4]u8 = undefined;
+        std.mem.writeInt(u32, &win_count_buffer, win_count, .little);
+        try win_count_file.pwriteAll(&win_count_buffer, 0);
+
+        resetHistory();
+        win_triggered = true;
+    }
+
     gl.clearColor(0.2, 0.4, 0.2, 1.0);
     gl.clear(gl.COLOR_BUFFER_BIT);
 
@@ -110,12 +194,38 @@ fn render(window: *seizer.Window) !void {
         card_tilemap.?.tilesheet.tile_size[1] * scale,
     };
     const margin = card_tilemap.?.margin * scale;
+    const marginf: f32 = @floatFromInt(card_tilemap.?.margin * scale);
     const hand_offset = [2]u32{
         card_tilemap.?.hand_offset[0] * scale,
         card_tilemap.?.hand_offset[1] * scale,
     };
+    const hand_offsetf = [2]f32{
+        @floatFromInt(hand_offset[0]),
+        @floatFromInt(hand_offset[1]),
+    };
     const tile_sizef = [2]f32{ @floatFromInt(tile_size[0]), @floatFromInt(tile_size[1]) };
 
+    const space_taken_by_board = [2]f32{
+        @floatFromInt(2 * margin + 8 * (margin + tile_size[0])),
+        @floatFromInt(2 * margin + 5 * (margin + tile_size[1])),
+    };
+    const board_offset = [2]f32{
+        (canvas.window_size[0] - space_taken_by_board[0]) / 2,
+        (canvas.window_size[1] - space_taken_by_board[1]) / 2,
+    };
+
+    {
+        _ = canvas.printText(
+            .{
+                canvas.window_size[0] - board_offset[0] - marginf - hand_offsetf[0],
+                board_offset[1] + marginf + hand_offsetf[1],
+            },
+            "Win Count: {}",
+            .{win_count},
+            .{ .@"align" = .right, .scale = scalef },
+        );
+    }
+
     for (&stacks, 0..) |*stack, i| {
         const deck_is_selected = selected_deck != null and selected_deck.? == stack;
         const deck_is_hovered = hovered_deck != null and hovered_deck.? == stack;
@@ -127,9 +237,11 @@ fn render(window: *seizer.Window) !void {
             [4]u8{ 0xFF, 0xFF, 0xFF, 0xFF };
 
         var pos = [2]f32{
-            @floatFromInt(margin + ((tile_size[0] + margin) * (i + 1))),
+            @floor(@as(f32, @floatFromInt(margin + ((tile_size[0] + margin) * (i + 1))))),
-            @floatFromInt(margin + margin + tile_size[1]),
+            @floor(@as(f32, @floatFromInt(margin + margin + tile_size[1]))),
         };
+        pos[0] += board_offset[0];
+        pos[1] += board_offset[1];
         canvas.rect(pos, tile_sizef, .{ .color = deck_color });
 
         for (stack.items, 0..) |card, j| {
@@ -151,14 +263,36 @@ fn render(window: *seizer.Window) !void {
         }
     }
 
+    if (haveWon()) {
+        const offset =
+            [2]f32{
+            2 * marginf + tile_sizef[0],
+            2 * marginf + tile_sizef[1],
+        };
+        _ = canvas.writeText(
+            .{
+                board_offset[0] + offset[0] + (space_taken_by_board[0] - offset[0]) / 2,
+                board_offset[1] + offset[1] + (space_taken_by_board[1] - offset[0]) / 2,
+            },
+            "You Win!",
+            .{
+                .baseline = .middle,
+                .@"align" = .center,
+                .scale = 2 * scalef,
+            },
+        );
+    }
+
     for (&foundations, 0..) |*foundation, i| {
         const is_hovered = hovered_deck != null and hovered_deck.? == foundation;
         const color = if (is_hovered) [4]u8{ 0xA0, 0xFF, 0xA0, 0xFF } else [4]u8{ 0xFF, 0xFF, 0xFF, 0xFF };
 
-        const pos = [2]f32{
+        var pos = [2]f32{
             @floatFromInt(margin),
             @floatFromInt(margin + ((margin + tile_size[1]) * (i + 1))),
         };
+        pos[0] += board_offset[0];
+        pos[1] += board_offset[1];
         canvas.rect(pos, tile_sizef, .{ .color = color });
 
         for (foundation.items) |card| {
@@ -167,6 +301,7 @@ fn render(window: *seizer.Window) !void {
                 .size = tile_sizef,
                 .color = color,
             });
+            pos[1] -= 0.25 * scalef;
         }
     }
 
@@ -178,6 +313,8 @@ fn render(window: *seizer.Window) !void {
             @floatFromInt(margin + margin + tile_size[0]),
             @floatFromInt(margin),
         };
+        pos[0] += board_offset[0];
+        pos[1] += board_offset[1];
         for (drawn_cards.items, 0..) |card, j| {
             const is_selected = deck_is_selected and j >= selected_card;
             const is_hovered = deck_is_hovered and j >= hovered_card;
@@ -202,6 +339,10 @@ fn render(window: *seizer.Window) !void {
         const color = if (is_hovered) [4]u8{ 0xA0, 0xFF, 0xA0, 0xFF } else [4]u8{ 0xFF, 0xFF, 0xFF, 0xFF };
 
         var pos = [2]f32{ @floatFromInt(margin), @floatFromInt(margin) };
+        pos[0] += board_offset[0];
+        pos[1] += board_offset[1];
+        canvas.rect(pos, tile_sizef, .{ .color = color });
+
         for (draw_pile.items) |card| {
             const tile_id = if (!draw_pile_exhausted) card_tilemap.?.back else card_tilemap.?.getTileForCard(card);
             card_tilemap.?.tilesheet.renderTile(&canvas, tile_id, pos, .{
@@ -212,9 +353,37 @@ fn render(window: *seizer.Window) !void {
         }
     }
 
+    if (show_menu) {
+        canvas.rect(
+            .{ canvas.window_size[0] / 3, canvas.window_size[1] / 3 },
+            .{ canvas.window_size[0] / 3, canvas.window_size[1] / 3 },
+            .{ .color = .{ 0, 0, 0, 0xFF } },
+        );
+        const x: f32 = canvas.window_size[0] / 2;
+        var y: f32 = canvas.window_size[1] / 3 + (canvas.font.lineHeight * scalef);
+        for (MENU_ITEMS, 0..) |menu_item, i| {
+            if (i == menu_item_selected) {
+                const size = canvas.printText(.{ x, y }, "> {s} <", .{menu_item}, .{ .@"align" = .center, .scale = scalef });
+                y += size[1];
+            } else {
+                const size = canvas.writeText(.{ x, y }, menu_item, .{ .@"align" = .center, .scale = scalef });
+                y += size[1];
+            }
+        }
+    }
+
     canvas.end();
 }
 
+pub fn haveWon() bool {
+    if (draw_pile.items.len > 0) return false;
+    if (drawn_cards.items.len > 0) return false;
+    for (stacks) |stack| {
+        if (stack.items.len > 0) return false;
+    }
+    return true;
+}
+
 pub fn makeStandardDeck(allocator: std.mem.Allocator) ![]Card {
     var deck = try allocator.alloc(Card, 52);
     errdefer allocator.free(deck);
@@ -235,14 +404,28 @@ pub fn makeStandardDeck(allocator: std.mem.Allocator) ![]Card {
 
 pub fn deselect(pressed: bool) !void {
     if (!pressed) return;
+    if (show_menu) return;
     selected_deck = null;
     selected_card = 0;
 }
 
 pub fn doSelectOrPlace(pressed: bool) !void {
     if (!pressed) return;
+    if (show_menu) {
+        const menu_item = MENU_ITEMS[menu_item_selected];
+        if (std.mem.eql(u8, menu_item, "Continue")) {
+            show_menu = false;
+        } else if (std.mem.eql(u8, menu_item, "New Game")) {
+            try resetGame();
+            show_menu = false;
+        } else if (std.mem.eql(u8, menu_item, "Quit")) {
+            window_global.setShouldClose(true);
+        }
+        return;
+    }
     if (selected_deck == null) {
         if (hovered_deck == &draw_pile and !draw_pile_exhausted) {
+            resetHistory();
             drawn_cards.ensureUnusedCapacity(gpa, 3) catch return;
             for (0..3) |_| {
                 if (draw_pile.popOrNull()) |card| drawn_cards.appendAssumeCapacity(card);
@@ -265,9 +448,11 @@ pub fn doSelectOrPlace(pressed: bool) !void {
             }
         }
     } else if (hovered_deck == selected_deck) {
+        const snapshot = try Snapshot.initFromCurrentGlobalState();
         const selected_substack = selected_deck.?.items[selected_card..];
 
         // try to move all selected cards into the foundations
+        var cards_moved = false;
         move_cards_to_foundations: for (0..selected_substack.len) |_| {
             for (foundations[0..]) |*foundation| {
                 if (hovered_deck == foundation) break :move_cards_to_foundations;
@@ -282,14 +467,18 @@ pub fn doSelectOrPlace(pressed: bool) !void {
                     foundation.ensureUnusedCapacity(gpa, 1) catch continue;
                     foundation.appendAssumeCapacity(selected_deck.?.pop());
                     hovered_card = indexOfTopOfStack(hovered_deck.?.items);
+                    cards_moved = true;
                     break;
                 }
             } else {
                 break :move_cards_to_foundations;
             }
         }
+
+        try history.append(gpa, snapshot);
         selected_deck = null;
     } else {
+        const snapshot = try Snapshot.initFromCurrentGlobalState();
         if (selected_deck) |selected| move_from_selected_to_hovered: {
             const selected_substack = selected.items[selected_card..];
             if (selected_substack.len == 0) break :move_from_selected_to_hovered;
@@ -303,6 +492,7 @@ pub fn doSelectOrPlace(pressed: bool) !void {
                     hovered.appendSliceAssumeCapacity(selected_substack);
                     selected.shrinkRetainingCapacity(selected.items.len - selected_substack.len);
                     hovered_card = indexOfTopOfStack(hovered_deck.?.items);
+                    try history.append(gpa, snapshot);
                     break :move_from_selected_to_hovered;
                 }
 
@@ -311,6 +501,7 @@ pub fn doSelectOrPlace(pressed: bool) !void {
                         hovered.ensureUnusedCapacity(gpa, 1) catch break :move_from_selected_to_hovered;
                         hovered.appendAssumeCapacity(selected_deck.?.pop());
                         hovered_card = indexOfTopOfStack(hovered_deck.?.items);
+                        try history.append(gpa, snapshot);
                         break :move_from_selected_to_hovered;
                     } else for (foundations[0..]) |*foundation| {
                         if (foundation != selected) continue;
@@ -322,6 +513,7 @@ pub fn doSelectOrPlace(pressed: bool) !void {
                             foundation.ensureUnusedCapacity(gpa, 1) catch continue;
                             foundation.appendAssumeCapacity(selected_deck.?.pop());
                             hovered_card = indexOfTopOfStack(hovered_deck.?.items);
+                            try history.append(gpa, snapshot);
                             break :move_from_selected_to_hovered;
                         }
                     }
@@ -339,6 +531,7 @@ pub fn doSelectOrPlace(pressed: bool) !void {
             hovered.appendSliceAssumeCapacity(selected_substack);
             selected.shrinkRetainingCapacity(selected.items.len - selected_substack.len);
             hovered_card = indexOfTopOfStack(hovered_deck.?.items);
+            try history.append(gpa, snapshot);
         }
         selected_deck = null;
     }
@@ -346,6 +539,7 @@ pub fn doSelectOrPlace(pressed: bool) !void {
 
 pub fn moveLeft(pressed: bool) !void {
     if (!pressed) return;
+    if (show_menu) return;
     if (hovered_deck == null) {
         hovered_deck = &draw_pile;
         hovered_card = 0;
@@ -378,6 +572,7 @@ pub fn moveLeft(pressed: bool) !void {
 
 pub fn moveRight(pressed: bool) !void {
     if (!pressed) return;
+    if (show_menu) return;
     if (hovered_deck == null) {
         hovered_deck = &draw_pile;
         hovered_card = 0;
@@ -411,7 +606,10 @@ pub fn moveRight(pressed: bool) !void {
 pub fn moveUp(pressed: bool) !void {
     if (!pressed) return;
 
-    if (hovered_deck == null) {
+    if (show_menu) {
+        if (menu_item_selected == 0) menu_item_selected = MENU_ITEMS.len;
+        menu_item_selected -= 1;
+    } else if (hovered_deck == null) {
         hovered_deck = &draw_pile;
         hovered_card = 0;
     } else if (hovered_deck == &draw_pile) {
@@ -452,7 +650,10 @@ pub fn moveUp(pressed: bool) !void {
 
 pub fn moveDown(pressed: bool) !void {
     if (!pressed) return;
-    if (hovered_deck == null) {
+    if (show_menu) {
+        menu_item_selected += 1;
+        menu_item_selected %= MENU_ITEMS.len;
+    } else if (hovered_deck == null) {
         hovered_deck = &draw_pile;
         hovered_card = 0;
     } else if (hovered_deck == &draw_pile) {
@@ -491,6 +692,20 @@ pub fn moveDown(pressed: bool) !void {
     }
 }
 
+pub fn undo(pressed: bool) !void {
+    if (!pressed) return;
+    if (history.popOrNull()) |snapshot_const| {
+        var snapshot = snapshot_const;
+        defer snapshot.deinit();
+        try snapshot.restore();
+    }
+}
+
+pub fn toggleMenu(pressed: bool) !void {
+    if (!pressed) return;
+    show_menu = !show_menu;
+}
+
 pub fn indexOfTopOfStack(cards: []Card) usize {
     if (cards.len < 2) return 0;
 
@@ -504,6 +719,86 @@ pub fn indexOfTopOfStack(cards: []Card) usize {
     return index;
 }
 
+const Snapshot = struct {
+    draw_pile: []Card,
+    draw_pile_exhausted: bool,
+    drawn_cards: []Card,
+    stacks: [7][]Card,
+    foundations: [4][]Card,
+    selected_deck: *std.ArrayListUnmanaged(Card),
+    selected_card: usize,
+
+    pub fn initFromCurrentGlobalState() !Snapshot {
+        const snapshot_selected_deck = selected_deck orelse return error.InvalidSelectionForSnapshot;
+
+        const snapshot_draw_pile = try gpa.dupe(Card, draw_pile.items);
+        errdefer gpa.free(snapshot_draw_pile);
+        const snapshot_drawn_cards = try gpa.dupe(Card, drawn_cards.items);
+        errdefer gpa.free(snapshot_drawn_cards);
+
+        var snapshot_stacks: [7][]Card = undefined;
+        for (&snapshot_stacks, &stacks) |*snapshot_stack, stack| {
+            snapshot_stack.* = try gpa.dupe(Card, stack.items);
+        }
+
+        var snapshot_foundations: [4][]Card = undefined;
+        for (&snapshot_foundations, &foundations) |*snapshot_foundation, foundation| {
+            snapshot_foundation.* = try gpa.dupe(Card, foundation.items);
+        }
+
+        return Snapshot{
+            .draw_pile = snapshot_draw_pile,
+            .draw_pile_exhausted = draw_pile_exhausted,
+            .drawn_cards = snapshot_drawn_cards,
+            .stacks = snapshot_stacks,
+            .foundations = snapshot_foundations,
+            .selected_deck = snapshot_selected_deck,
+            .selected_card = selected_card,
+        };
+    }
+
+    pub fn deinit(snapshot: *@This()) void {
+        gpa.free(snapshot.draw_pile);
+        gpa.free(snapshot.drawn_cards);
+    }
+
+    pub fn restore(snapshot: @This()) !void {
+        // ensure there is enough space for all the cards
+        try draw_pile.ensureTotalCapacity(gpa, snapshot.draw_pile.len);
+        try drawn_cards.ensureTotalCapacity(gpa, snapshot.drawn_cards.len);
+        for (&snapshot.stacks, &stacks) |snapshot_stack, *stack| {
+            try stack.ensureTotalCapacity(gpa, snapshot_stack.len);
+        }
+        for (&snapshot.foundations, &foundations) |snapshot_foundation, *foundation| {
+            try foundation.ensureTotalCapacity(gpa, snapshot_foundation.len);
+        }
+
+        // reset the state
+        draw_pile.shrinkRetainingCapacity(0);
+        draw_pile.appendSliceAssumeCapacity(snapshot.draw_pile);
+
+        draw_pile_exhausted = snapshot.draw_pile_exhausted;
+
+        drawn_cards.shrinkRetainingCapacity(0);
+        drawn_cards.appendSliceAssumeCapacity(snapshot.drawn_cards);
+
+        for (&snapshot.stacks, &stacks) |snapshot_stack, *stack| {
+            stack.shrinkRetainingCapacity(0);
+            stack.appendSliceAssumeCapacity(snapshot_stack);
+        }
+
+        for (&snapshot.foundations, &foundations) |snapshot_foundation, *foundation| {
+            foundation.shrinkRetainingCapacity(0);
+            foundation.appendSliceAssumeCapacity(snapshot_foundation);
+        }
+
+        selected_deck = null;
+        selected_card = 0;
+        hovered_deck = snapshot.selected_deck;
+        hovered_card = snapshot.selected_card;
+    }
+};
+
 const DeckSprites = assets.DeckSprites;
 const Card = assets.Card;