Implement departures screen

src/departure.zig

@@ -1,13 +1,101 @@
+const std = @import("std");
 const raylib = @import("raylib.zig");
 const rl = raylib.rl;
 const AppState = @import("state.zig");
+const Curl = @import("curl.zig");
+
+fn fetchThread(state: *AppState) !void {
+    std.debug.print("[departure/fetchThread] Started\n", .{});
+    defer std.debug.print("[departure/fetchThread] Ended\n", .{});
+    defer state.departure_screen_state.fetch_thread = null;
+    const allocator = state.allocator;
+    var station_id_buf = std.BoundedArray(u8, 10){};
+    var include_tram = false;
+    var curl = Curl.init() orelse return;
+    defer curl.deinit();
+
+    while (state.departure_screen_state.fetch_thread != null) {
+        const fetch_anyway = state.departure_screen_state.should_refresh;
+        if (!fetch_anyway and std.mem.eql(u8, station_id_buf.slice(), state.departure_screen_state.station_id.items) and include_tram == state.departure_screen_state.include_tram) {
+            std.time.sleep(100 * 1000);
+            continue;
+        }
+
+        station_id_buf.resize(state.departure_screen_state.station_id.items.len) catch continue;
+        std.mem.copyForwards(u8, station_id_buf.slice(), state.departure_screen_state.station_id.items);
+        include_tram = state.departure_screen_state.include_tram;
+        std.debug.print("[departure/fetchThread] Detected update: {s}\n", .{station_id_buf.slice()});
+
+        curl.reset();
+
+        const departures_base = std.fmt.allocPrintZ(
+            allocator,
+            "https://v6.db.transport.rest/stops/{s}/departures",
+            .{state.departure_screen_state.station_id.items},
+        ) catch continue;
+        defer allocator.free(departures_base);
+        var departures_uri = std.Uri.parse(departures_base) catch unreachable;
+        const query = std.fmt.allocPrint(allocator, "duration=300&bus=false&ferry=false&taxi=false&pretty=false{s}", .{if (include_tram) "" else "&tram=false&subway=false"}) catch continue;
+        defer allocator.free(query);
+        departures_uri.query = query;
+        defer departures_uri.query = null;
+        std.debug.print("[departure/fetchThread] Making request to: {}\n", .{departures_uri});
+
+        const url = try std.fmt.allocPrintZ(allocator, "{}", .{departures_uri});
+        defer allocator.free(url);
+        _ = curl.setopt(.url, .{url.ptr});
+
+        var result = std.ArrayList(u8).init(allocator);
+        defer result.deinit();
+        _ = curl.setopt(.write_function, .{Curl.Utils.array_list_append});
+        _ = curl.setopt(.write_data, .{&result});
+
+        const code = curl.perform();
+        std.debug.print("[departure/fetchThread] cURL Code: {}\n", .{code});
+        if (code != 0) continue;
+
+        std.debug.print("[departure/fetchThread] Fetched data: <redacted>(len: {})\n", .{result.items.len});
+        const parsed = std.json.parseFromSlice(std.json.Value, allocator, result.items, .{}) catch |err| {
+            std.debug.print("[departure/fetchThread] JSON parse error: {}\n", .{err});
+            continue;
+        };
+        if (state.departure_screen_state.fetch_result) |old_result| {
+            old_result.deinit();
+        }
+        state.departure_screen_state.fetch_result = parsed;
+        state.departure_screen_state.should_refresh = false;
+    }
+    if (state.departure_screen_state.fetch_result) |old_result| {
+        old_result.deinit();
+        state.departure_screen_state.fetch_result = null;
+    }
+}
 
 pub fn render(state: *AppState) !void {
+    const allocator = state.allocator;
+    var ds = &state.departure_screen_state;
+
+    if (ds.fetch_thread == null) {
+        ds.fetch_thread = std.Thread.spawn(.{}, fetchThread, .{state}) catch null;
+    }
+
     while (raylib.GetKeyPressed()) |key| {
         switch (key) {
             rl.KEY_LEFT => {
                 state.screen = .home;
             },
+            rl.KEY_R => {
+                ds.should_refresh = true;
+            },
+            rl.KEY_MINUS, rl.KEY_KP_SUBTRACT => {
+                ds.max_next_trains = @max(1, ds.max_next_trains - 1);
+            },
+            rl.KEY_EQUAL, rl.KEY_KP_EQUAL => {
+                ds.max_next_trains = @min(ds.max_next_trains + 1, if (ds.fetch_result) |fr| @as(c_int, @intCast(fr.value.object.get("departures").?.array.items.len)) else 5);
+            },
+            rl.KEY_T => {
+            	ds.include_tram = !ds.include_tram;
+            },
             else => {},
         }
     }
@@ -15,8 +103,186 @@ pub fn render(state: *AppState) !void {
     rl.BeginDrawing();
     defer rl.EndDrawing();
 
-    rl.ClearBackground(raylib.ColorInt(0x18226f));
-    rl.DrawText(state.departure_screen_state.station_id.items.ptr, 16, 16, 32, rl.WHITE);
+    const db_blue = raylib.ColorInt(0x18226f);
+    rl.ClearBackground(if (ds.should_refresh) rl.ORANGE else db_blue);
+    if (ds.fetch_result) |data| {
+        if (data.value.object.get("departures")) |departures_raw| {
+            const departures = departures_raw.array.items;
+            var not_cancelled = std.ArrayList(std.json.Value).init(allocator);
+            defer not_cancelled.deinit();
+            for (departures) |d| {
+                if (d.object.get("cancelled")) |c| {
+                    switch (c) {
+                        .bool => |b| {
+                            if (b) {
+                                continue;
+                            }
+                        },
+                        else => {},
+                    }
+                }
+                not_cancelled.append(d) catch continue;
+            }
+            if (not_cancelled.items.len > 0) {
+                var y: c_int = 16;
+                // Info area
+                y += 32 + 16;
+                const first = not_cancelled.items[0].object;
+
+                station_name_blk: {
+                    const station_name = std.fmt.allocPrintZ(allocator, "{s}", .{first.get("stop").?.object.get("name").?.string}) catch break :station_name_blk;
+                    defer allocator.free(station_name);
+                    rl.SetWindowTitle(station_name.ptr);
+                    raylib.DrawRightAlignedText(station_name.ptr, rl.GetScreenWidth() - 4, 4, 14, rl.WHITE);
+                }
+
+                const line = try std.fmt.allocPrintZ(allocator, "{s}", .{first.get("line").?.object.get("name").?.string});
+                defer allocator.free(line);
+                const destination = try std.fmt.allocPrintZ(allocator, "{s}", .{first.get("direction").?.string});
+                defer allocator.free(destination);
+                var next_y = y;
+                if (state.db_font) |db_font| {
+                    next_y += @intFromFloat(raylib.DrawAndMeasureTextEx(db_font, line.ptr, 16, @floatFromInt(y), 32, 1, rl.WHITE).y);
+                } else {
+                    rl.DrawText(line.ptr, 16, y, 32, rl.WHITE);
+                    next_y += 32;
+                }
+                next_y += 16;
+                if (ds.platform.items.len == 0) blk: {
+                    if (first.get("platform")) |platform_raw| {
+                        switch (platform_raw) {
+                            .string => |p| {
+                                const platform = std.fmt.allocPrintZ(allocator, "{s}", .{p}) catch break :blk;
+                                defer allocator.free(platform);
+                                if (state.db_font) |db_font| {
+                                    raylib.DrawRightAlignedTextEx(db_font, platform.ptr, @floatFromInt(rl.GetScreenWidth() - 16), @floatFromInt(y), 40, 1, rl.WHITE);
+                                } else {
+                                    raylib.DrawRightAlignedText(platform.ptr, rl.GetScreenWidth() - 16, y, 40, rl.WHITE);
+                                }
+                            },
+                            else => {},
+                        }
+                    }
+                }
+                y = next_y;
+                if (state.db_font) |db_font| {
+                    y += @intFromFloat(raylib.DrawAndMeasureTextEx(
+                        db_font,
+                        destination.ptr,
+                        16,
+                        @floatFromInt(y),
+                        56,
+                        1,
+                        rl.WHITE,
+                    ).y);
+                } else {
+                    rl.DrawText(destination.ptr, 16, y, 56, rl.WHITE);
+                    y += 56;
+                }
+                y += 16;
+            }
+            if (not_cancelled.items.len > 1) {
+                var max_trains: c_int = @intCast(not_cancelled.items.len - 1);
+                if (max_trains > ds.max_next_trains) max_trains = ds.max_next_trains;
+                const font_size: c_int = 32;
+                var x: c_int = 16;
+                var y = rl.GetScreenHeight() - (font_size + 8) * max_trains - 4;
+                rl.DrawRectangle(0, y, rl.GetScreenWidth(), rl.GetScreenHeight(), rl.WHITE);
+                y += 8;
+                const label_measurement_width = if (state.db_font) |db_font| @as(c_int, @intFromFloat(raylib.DrawAndMeasureTextEx(
+                	db_font,
+                    if (max_trains == 1) "Next train: " else "Next trains: ",
+                    @floatFromInt(x),
+                    @floatFromInt(y),
+                    @floatFromInt(font_size),
+                    1,
+                    db_blue,
+                ).x)) else raylib.DrawAndMeasureText(
+                    if (max_trains == 1) "Next train: " else "Next trains: ",
+                    x,
+                    y,
+                    font_size,
+                    db_blue,
+                ).width;
+                x += label_measurement_width;
+
+                // Compute line name width
+                var line_name_width: c_int = 0;
+                for (not_cancelled.items, 0..) |dep_raw, idx| {
+                    if (idx == 0) continue;
+                    if (idx > max_trains) break;
+                    const second = dep_raw.object;
+                    const next_train_line = try std.fmt.allocPrintZ(
+                        allocator,
+                        "{s} ",
+                        .{
+                            second.get("line").?.object.get("name").?.string,
+                        },
+                    );
+                    defer allocator.free(next_train_line);
+                    if (state.db_font) |db_font| {
+                        line_name_width = @max(
+                            line_name_width,
+                            @as(c_int, @intFromFloat(rl.MeasureTextEx(db_font, next_train_line.ptr, @floatFromInt(font_size), 1).x)),
+                        );
+                    } else {
+                        line_name_width = @max(line_name_width, rl.MeasureText(next_train_line.ptr, font_size));
+                    }
+                }
+                const destionation_x = x + line_name_width;
+
+                for (not_cancelled.items, 0..) |dep_raw, idx| {
+                    if (idx == 0) continue;
+                    if (idx > max_trains) break;
+                    const second = dep_raw.object;
+                    const next_train_line = try std.fmt.allocPrintZ(
+                        allocator,
+                        "{s} ",
+                        .{
+                            second.get("line").?.object.get("name").?.string,
+                        },
+                    );
+                    defer allocator.free(next_train_line);
+                    const next_train_direction = try std.fmt.allocPrintZ(
+                        allocator,
+                        "{s}",
+                        .{
+                            second.get("direction").?.string,
+                        },
+                    );
+                    defer allocator.free(next_train_direction);
+                    if (state.db_font) |db_font| {
+	                    rl.DrawTextEx(db_font, next_train_line.ptr, .{ .x = @floatFromInt(x), .y = @floatFromInt(y) }, font_size, 1, db_blue);
+	                    rl.DrawTextEx(db_font, next_train_direction.ptr, .{ .x = @floatFromInt(destionation_x), .y = @floatFromInt(y) }, font_size, 1, db_blue);
+                    } else {
+	                    rl.DrawText(next_train_line.ptr, x, y, font_size, db_blue);
+	                    rl.DrawText(next_train_direction.ptr, destionation_x, y, font_size, db_blue);
+                    }
+                    if (ds.platform.items.len == 0) blk: {
+                        if (second.get("platform")) |platform_raw| {
+                            switch (platform_raw) {
+                                .string => |p| {
+                                    const platform = std.fmt.allocPrintZ(allocator, "{s}", .{p}) catch break :blk;
+                                    defer allocator.free(platform);
+                                    if (state.db_font) |db_font| {
+                                        raylib.DrawRightAlignedTextEx(db_font, platform.ptr, @floatFromInt(rl.GetScreenWidth() - 16), @floatFromInt(y), @floatFromInt(font_size), 1, db_blue);
+                                    } else {
+                                        raylib.DrawRightAlignedText(platform.ptr, rl.GetScreenWidth() - 16, y, font_size, db_blue);
+                                    }
+                                },
+                                else => {},
+                            }
+                        }
+                    }
+                    y += font_size + 4;
+                    rl.DrawLine(x, y, rl.GetScreenWidth() - 8, y, db_blue);
+                    y += 4;
+                }
+            }
+        }
+    } else {
+        rl.DrawText(state.departure_screen_state.station_id.items.ptr, 16, 16, 32, rl.WHITE);
+    }
 
     state.close_app = rl.WindowShouldClose();
 }

src/state.zig

@@ -23,7 +23,12 @@ pub const DepartureScreenState = struct {
     station_id: std.ArrayListUnmanaged(u8),
     platform: std.ArrayListUnmanaged(u8),
     departure_date: std.time.Instant,
-    loading: bool = false,
+    fetch_thread: ?std.Thread = null,
+    last_refresh_time: std.time.Instant = std.mem.zeroInit(std.time.Instant, .{}),
+    fetch_result: ?std.json.Parsed(std.json.Value) = null,
+    should_refresh: bool = false,
+    max_next_trains: c_int = 5,
+    include_tram: bool = false,
 };
 
 allocator: std.mem.Allocator,