zcatgui/examples/android_demo.zig

//! Android Demo - zcatgui running on Android
//!
//! Build with:
//!   zig build android-demo -Dtarget=aarch64-linux-android
//!
//! This creates a native Android activity that runs the zcatgui demo.

const std = @import("std");
const zcatgui = @import("zcatgui");

const AndroidBackend = zcatgui.backend.android.AndroidBackend;
const log = zcatgui.backend.android.log;

// Global state (Android native activities are single-instance)
var ctx: ?*zcatgui.Context = null;
var allocator: std.mem.Allocator = undefined;

// Demo state
var counter: i32 = 0;
var checkbox_checked: bool = false;
var slider_value: f32 = 0.5;

/// Main loop - called from a separate thread
fn mainLoop() void {
    allocator = std.heap.page_allocator;

    // Wait for window to be ready
    while (!zcatgui.backend.android.isRunning()) {
        std.Thread.sleep(10 * std.time.ns_per_ms);
    }

    const size = zcatgui.backend.android.getWindowSize();
    if (size.width == 0 or size.height == 0) {
        log("Invalid window size", .{});
        return;
    }

    // Initialize context
    const c = allocator.create(zcatgui.Context) catch {
        log("Failed to allocate context", .{});
        return;
    };
    c.* = zcatgui.Context.init(allocator, size.width, size.height) catch {
        log("Failed to init context", .{});
        allocator.destroy(c);
        return;
    };
    ctx = c;

    log("zcatgui Android initialized: {}x{}", .{ size.width, size.height });

    // Main loop
    while (zcatgui.backend.android.isRunning()) {
        frame() catch |err| {
            log("Frame error: {}", .{err});
            break;
        };

        // ~60 FPS
        std.Thread.sleep(16 * std.time.ns_per_ms);
    }

    // Cleanup
    if (ctx) |context| {
        context.deinit();
        allocator.destroy(context);
        ctx = null;
    }

    log("zcatgui Android shutdown", .{});
}

fn frame() !void {
    const c = ctx orelse return;
    const be = zcatgui.backend.android.getBackend() orelse return;

    // Get current size (may have changed due to rotation)
    const size = zcatgui.backend.android.getWindowSize();
    if (size.width == 0 or size.height == 0) return;

    // Process events
    while (be.backend().pollEvent()) |event| {
        switch (event) {
            .quit => {
                be.running = false;
                return;
            },
            .key => |k| c.input.handleKeyEvent(k),
            .mouse => |m| {
                c.input.setMousePos(m.x, m.y);
                if (m.button) |btn| {
                    c.input.setMouseButton(btn, m.pressed);
                }
                if (m.scroll_x != 0 or m.scroll_y != 0) {
                    c.input.addScroll(m.scroll_x, m.scroll_y);
                }
            },
            .resize => |r| {
                // Handle resize (screen rotation)
                _ = r;
            },
            .text_input => {},
        }
    }

    // Begin frame
    c.beginFrame();

    // Set theme (use high contrast for mobile)
    const theme = zcatgui.Style.Theme.dark;

    // Large touch-friendly UI
    c.layout.row_height = 60;

    // Title
    zcatgui.labelEx(c, "zcatgui Android Demo", .{
        .alignment = .center,
        .color = theme.primary,
    });

    c.layout.row_height = 40;
    zcatgui.label(c, "Touch to interact!");

    // Spacing
    c.layout.row_height = 20;
    zcatgui.label(c, "");

    // Counter section
    c.layout.row_height = 50;

    var buf: [64]u8 = undefined;
    const counter_text = std.fmt.bufPrint(&buf, "Counter: {d}", .{counter}) catch "Counter: ?";
    zcatgui.label(c, counter_text);

    // Large buttons for touch
    c.layout.row_height = 80;

    if (zcatgui.button(c, "+")) {
        counter += 1;
    }

    if (zcatgui.button(c, "-")) {
        counter -= 1;
    }

    if (zcatgui.button(c, "Reset")) {
        counter = 0;
    }

    // Checkbox
    c.layout.row_height = 20;
    zcatgui.label(c, "");
    c.layout.row_height = 60;

    if (zcatgui.checkbox(c, &checkbox_checked, "Enable feature")) {
        // Checkbox changed
    }

    // Progress bar
    c.layout.row_height = 20;
    zcatgui.label(c, "");
    c.layout.row_height = 40;

    var slider_buf: [32]u8 = undefined;
    const slider_label = std.fmt.bufPrint(&slider_buf, "Progress: {d:.0}%", .{slider_value * 100}) catch "Progress: ?";
    zcatgui.label(c, slider_label);

    c.layout.row_height = 30;
    _ = zcatgui.widgets.progress.bar(c, slider_value);

    // End frame
    c.endFrame();

    // Render
    var fb = try zcatgui.render.Framebuffer.init(allocator, size.width, size.height);
    defer fb.deinit();

    fb.clear(theme.background);

    var renderer = zcatgui.render.SoftwareRenderer.init(&fb);
    renderer.executeAll(c.commands.items);

    // Present to screen
    be.backend().present(&fb);
}

// Thread entry point - Android's main thread handles UI, we run zcatgui in background
export fn android_main() void {
    mainLoop();
}

// Alternative: Use native activity thread directly (for simpler apps)
comptime {
    // Ensure ANativeActivity_onCreate is exported from android.zig
    _ = zcatgui.backend.android;
}