const builtin = @import("builtin");
const options = @import("build_options");
const std = @import("std");
const glfw = @import("glfw");
const fontconfig = @import("fontconfig");
const freetype = @import("freetype");
const harfbuzz = @import("harfbuzz");
const tracy = @import("tracy");

const App = @import("App.zig");
const cli_args = @import("cli_args.zig");
const Config = @import("config.zig").Config;

const log = std.log.scoped(.main);

pub fn main() !void {
    // Output some debug information right away
    log.info("dependency harfbuzz={s}", .{harfbuzz.versionString()});
    if (builtin.os.tag == .linux) {
        log.info("dependency fontconfig={d}", .{fontconfig.version()});
    }

    const gpa = gpa: {
        // Use the libc allocator if it is available beacuse it is WAY
        // faster than GPA. We only do this in release modes so that we
        // can get easy memory leak detection in debug modes.
        if (builtin.link_libc) {
            switch (builtin.mode) {
                .ReleaseSafe, .ReleaseFast => break :gpa std.heap.c_allocator,
                else => {},
            }
        }

        // We don't ever deinit our GPA because the process cleanup will
        // clean it up. This defer isn't in the right location anyways because
        // it'll deinit on return from blk.
        // defer _ = general_purpose_allocator.deinit();

        var general_purpose_allocator = std.heap.GeneralPurposeAllocator(.{}){};
        break :gpa general_purpose_allocator.allocator();
    };

    // If we're tracing, then wrap memory so we can trace allocations
    const alloc = if (!tracy.enabled) gpa else alloc: {
        var tracy_alloc = tracy.allocator(gpa, null);
        break :alloc tracy_alloc.allocator();
    };

    // Parse the config from the CLI args
    var config = config: {
        var result = try Config.default(alloc);
        errdefer result.deinit();
        var iter = try std.process.argsWithAllocator(alloc);
        defer iter.deinit();
        try cli_args.parse(Config, alloc, &result, &iter);
        break :config result;
    };
    defer config.deinit();

    // Parse the config files
    // TODO(mitchellh): support nesting (config-file in a config file)
    // TODO(mitchellh): detect cycles when nesting
    if (config.@"config-file".list.items.len > 0) {
        const len = config.@"config-file".list.items.len;
        const cwd = std.fs.cwd();
        for (config.@"config-file".list.items) |path| {
            var file = try cwd.openFile(path, .{});
            defer file.close();

            var buf_reader = std.io.bufferedReader(file.reader());
            var iter = cli_args.lineIterator(buf_reader.reader());

            try cli_args.parse(Config, alloc, &config, &iter);

            // We don't currently support adding more config files to load
            // from within a loaded config file. This can be supported
            // later.
            if (config.@"config-file".list.items.len > len)
                return error.ConfigFileInConfigFile;
        }
    }
    log.info("config={}", .{config});

    // We want to log all our errors
    glfw.setErrorCallback(glfwErrorCallback);

    // Initialize glfw
    try glfw.init(.{});
    defer glfw.terminate();

    // Run our app
    var app = try App.init(alloc, &config);
    defer app.deinit();
    try app.run();
}

// Required by tracy/tracy.zig to enable/disable tracy support.
pub fn tracy_enabled() bool {
    return options.tracy_enabled;
}

fn glfwErrorCallback(code: glfw.Error, desc: [:0]const u8) void {
    log.warn("glfw error={} message={s}", .{ code, desc });
}

test {
    _ = @import("Atlas.zig");
    _ = @import("Grid.zig");
    _ = @import("Pty.zig");
    _ = @import("Command.zig");
    _ = @import("TempDir.zig");
    _ = @import("font/main.zig");
    _ = @import("terminal/Terminal.zig");
    _ = @import("input.zig");

    // Libraries
    _ = @import("libuv");
    _ = @import("segmented_pool.zig");
    _ = @import("terminal/main.zig");

    // TODO
    _ = @import("config.zig");
    _ = @import("cli_args.zig");
    _ = @import("lru.zig");
}