// Main function
// Copyright (C) 2021  Nguyễn Gia Phong
//
// This file is part of Black Shades.
//
// Black Shades is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published
// by the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Black Shades is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Black Shades.  If not, see <https://www.gnu.org/licenses/>.

pub const c = @cImport({
    @cInclude("Game.h");
    @cInclude("Constants.h");
});

const Loca = @import("loca").Loca;
const al = @import("zeal");
const allocator = std.heap.c_allocator;
const configuration = @import("config.zig");
const free = std.c.free;
const gf = @import("gfz");
const gl = @import("zgl");
const misc = @import("misc.zig");
const std = @import("std");

var game: *c.Game = undefined;

fn resizeWindow(window: ?*gf.Window.Impl,
                width: c_int, height: c_int) callconv(.C) void {
    c.resizeWindow(game, width, height);
}

fn handleKey(window: ?*gf.Window.Impl, key: c_int, scancode: c_int,
             action: c_int, mods: c_int) callconv(.C) void {
    c.handleKey(game, key, action, mods);
}

fn look(window: ?*gf.Window.Impl, xpos: f64, ypos: f64) callconv(.C) void {
    c.look(game, xpos, ypos);
}

fn click(window: ?*gf.Window.Impl, button: c_int,
         action: c_int, mods: c_int) callconv(.C) void {
    c.click(game, button, action, mods);
}

pub fn main() !void {
    const loca = try Loca.init(allocator, .{});
    defer loca.deinit();
    const config = try configuration.parse(loca.user_config);
    defer free(config.levels.ptr);

    try gf.init();
    defer gf.deinit() catch unreachable;
    const window = try gf.Window.create(config.width, config.height,
                                        "Black Shades", .{}, .{});
    try window.makeCurrent();

    game = c.makeGame(@bitCast(c.Config, config)).?;
    try window.setSizeCallback(resizeWindow);
    try gf.swapInterval(@boolToInt(config.vsync));
    c.initGl(game);

    if (try gf.rawMouseMotionSupported())
        try window.setInputMode(.raw_mouse_motion, true);
    try window.setCursorPosCallback(look);
    try window.setInputMode(.sticky_mouse_buttons, true);
    try window.setMouseButtonCallback(click);
    try window.setInputMode(.sticky_keys, true);
    try window.setKeyCallback(handleKey);

    const device = try al.Device.init(null);
    defer device.deinit() catch unreachable;
    const context = try al.Context.init(device, &.{});
    defer context.deinit() catch unreachable;
    try context.makeCurrent();

    c.initGame(game);
    defer c.closeGame(game);
    while (!try window.shouldClose()) {
        c.eventLoop(game);
        try window.swapBuffers();
        try gf.pollEvents();
    }
}