const ext = @cImport({
    @cInclude("SDL2/SDL.h");
});

const io = @import("./io.zig");
const stack = @import("./stack.zig");
const std = @import("std");
const sys = @import("./sys.zig");

///
/// Entry point.
///
pub fn main() anyerror!void {
    if (ext.SDL_Init(ext.SDL_INIT_EVERYTHING) != 0) {
        ext.SDL_LogCritical(ext.SDL_LOG_CATEGORY_APPLICATION, "Failed to initialize SDL2 runtime");

        return error.InitFailure;
    }

    defer ext.SDL_Quit();

    const pref_path = create_pref_path: {
        const path = ext.SDL_GetPrefPath("ona", "ona") orelse {
            ext.SDL_LogCritical(ext.SDL_LOG_CATEGORY_APPLICATION, "Failed to load user path");

            return error.InitFailure;
        };

        break: create_pref_path path[0 .. std.mem.len(path)];
    };

    defer ext.SDL_free(pref_path.ptr);

    const window = create_window: {
        const pos = ext.SDL_WINDOWPOS_UNDEFINED;
        var flags = @as(u32, 0);

        break: create_window ext.SDL_CreateWindow("Ona", pos, pos, 640, 480, flags) orelse {
            ext.SDL_LogCritical(ext.SDL_LOG_CATEGORY_APPLICATION, "Failed to load SDL2 window");

            return error.InitFailure;
        };
    };

    defer ext.SDL_DestroyWindow(window);

    const renderer = create_renderer: {
        var flags = @as(u32, 0);

        break: create_renderer ext.SDL_CreateRenderer(window, -1, flags) orelse {
            ext.SDL_LogCritical(ext.SDL_LOG_CATEGORY_APPLICATION, "Failed to load SDL2 renderer");

            return error.InitFailure;
        };
    };

    defer ext.SDL_DestroyRenderer(renderer);

    var event_loop = sys.EventLoop{};
    var is_running = true;

    while (is_running) {
        var event = std.mem.zeroes(ext.SDL_Event);

        while (ext.SDL_PollEvent(&event) != 0) {
            switch (event.type) {
                ext.SDL_QUIT => is_running = false,
                else => {},
            }
        }

        if (ext.SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255) != 0) {
            ext.SDL_LogError(ext.SDL_LOG_CATEGORY_VIDEO, ext.SDL_GetError());
            ext.SDL_ClearError();
        }

        if (ext.SDL_RenderClear(renderer) != 0) {
            ext.SDL_LogError(ext.SDL_LOG_CATEGORY_VIDEO, ext.SDL_GetError());
            ext.SDL_ClearError();
        }

        ext.SDL_RenderPresent(renderer);
        event_loop.tick();
        ext.SDL_Delay(1);
    }
}