const ig = @import("cimgui");
const sokol = @import("sokol");
const slog = sokol.log;
const sg = sokol.gfx;
const sapp = sokol.app;
const sglue = sokol.glue;
const simgui = sokol.imgui;

const state = struct {
    var pass_action: sg.PassAction = .{};
};

export fn init() void {
    // initialize sokol-gfx
    sg.setup(.{
        .environment = sglue.environment(),
        .logger = .{ .func = slog.func },
    });
    // initialize sokol-imgui
    simgui.setup(.{
        .logger = .{ .func = slog.func },
    });

    // initial clear color
    state.pass_action.colors[0] = .{
        .load_action = .CLEAR,
        .clear_value = .{ .r = 0.0, .g = 0.5, .b = 1.0, .a = 1.0 },
    };
}

export fn frame() void {
    // call simgui.newFrame() before any ImGui calls
    simgui.newFrame(.{
        .width = sapp.width(),
        .height = sapp.height(),
        .delta_time = sapp.frameDuration(),
        .dpi_scale = sapp.dpiScale(),
    });

    //=== UI CODE STARTS HERE
    ig.igSetNextWindowPos(.{ .x = 10, .y = 10 }, ig.ImGuiCond_Once, .{ .x = 0, .y = 0 });
    ig.igSetNextWindowSize(.{ .x = 400, .y = 100 }, ig.ImGuiCond_Once);
    _ = ig.igBegin("Hello Dear ImGui!", 0, ig.ImGuiWindowFlags_None);
    _ = ig.igColorEdit3("Background", &state.pass_action.colors[0].clear_value.r, ig.ImGuiColorEditFlags_None);
    ig.igEnd();
    //=== UI CODE ENDS HERE

    // call simgui.render() inside a sokol-gfx pass
    sg.beginPass(.{ .action = state.pass_action, .swapchain = sglue.swapchain() });
    simgui.render();
    sg.endPass();
    sg.commit();
}

export fn cleanup() void {
    simgui.shutdown();
    sg.shutdown();
}

export fn event(ev: [*c]const sapp.Event) void {
    // forward input events to sokol-imgui
    _ = simgui.handleEvent(ev.*);
}

pub fn main() void {
    sapp.run(.{
        .init_cb = init,
        .frame_cb = frame,
        .cleanup_cb = cleanup,
        .event_cb = event,
        .window_title = "sokol-zig + Dear Imgui",
        .width = 800,
        .height = 600,
        .icon = .{ .sokol_default = true },
        .logger = .{ .func = slog.func },
    });
}