const std = @import("std");
pub usingnamespace @import("strings.zig");

pub const C = @import("c.zig");
pub const BuildTarget = enum { native, wasm, wasi };
pub const build_target: BuildTarget = comptime {
    if (std.Target.current.isWasm() and std.Target.current.getOsTag() == .wasi) {
        return BuildTarget.wasi;
    } else if (std.Target.current.isWasm()) {
        return BuildTarget.wasm;
    } else {
        return BuildTarget.native;
    }
};

pub const isWasm = build_target == .wasm;
pub const isNative = build_target == .native;
pub const isWasi = build_target == .wasi;
pub const isMac = build_target == .native and std.Target.current.os.tag == .macos;
pub const isBrowser = !isWasi and isWasm;
pub const isWindows = std.Target.current.os.tag == .windows;

pub const FeatureFlags = struct {
    pub const strong_etags_for_built_files = true;
    pub const keep_alive = true;

    // it just doesn't work well.
    pub const use_std_path_relative = false;
    pub const use_std_path_join = false;

    // Debug helpers
    pub const print_ast = false;
    pub const disable_printing_null = false;

    // This was a ~5% performance improvement
    pub const store_file_descriptors = !isWindows and !isBrowser;

    // This doesn't really seem to do anything for us
    pub const disable_filesystem_cache = false and std.Target.current.os.tag == .macos;

    pub const css_in_js_import_behavior = CSSModulePolyfill.facade;

    pub const only_output_esm = true;

    pub const jsx_runtime_is_cjs = true;

    pub const bundle_node_modules = true;

    pub const tracing = true;

    pub const CSSModulePolyfill = enum {
        // When you import a .css file and you reference the import in JavaScript
        // Just return whatever the property key they referenced was
        facade,
    };
};

pub const isDebug = std.builtin.Mode.Debug == std.builtin.mode;
pub const isTest = std.builtin.is_test;

pub const Output = struct {
    var source: *Source = undefined;
    pub const Source = struct {
        const StreamType = {
            if (isWasm) {
                return std.io.FixedBufferStream([]u8);
            } else {
                return std.fs.File;
                // var stdout = std.io.getStdOut();
                // return @TypeOf(std.io.bufferedWriter(stdout.writer()));
            }
        };
        stream: StreamType,
        error_stream: StreamType,
        out_buffer: []u8 = &([_]u8{}),
        err_buffer: []u8 = &([_]u8{}),

        pub fn init(
            stream: StreamType,
            err: StreamType,
        ) Source {
            return Source{ .stream = stream, .error_stream = err };
        }

        pub fn set(_source: *Source) void {
            source = _source;
        }
    };

    pub fn errorWriter() @typeInfo(@TypeOf(Source.StreamType.writer)).Fn.return_type.? {
        return source.error_stream.writer();
    }

    pub fn writer() @typeInfo(@TypeOf(Source.StreamType.writer)).Fn.return_type.? {
        return source.stream.writer();
    }

    pub fn flush() void {
        if (isNative) {
            // source.stream.flush() catch {};
            // source.error_stream.flush() catch {};
        }
    }

    pub fn printErrorable(comptime fmt: string, args: anytype) !void {
        if (isWasm) {
            try source.stream.seekTo(0);
            try source.stream.writer().print(fmt, args);
            const root = @import("root");
            root.console_log(root.Uint8Array.fromSlice(source.out_buffer[0..source.stream.pos]));
        } else {
            std.fmt.format(source.stream.writer(), fmt, args) catch unreachable;
        }
    }

    pub fn println(comptime fmt: string, args: anytype) void {
        if (fmt[fmt.len - 1] != '\n') {
            return print(fmt ++ "\n", args);
        }

        return print(fmt, args);
    }

    pub const debug = if (isDebug) _debug else _noop;

    fn _noop(comptime fmt: string, args: anytype) void {}

    pub fn _debug(comptime fmt: string, args: anytype) void {
        if (fmt[fmt.len - 1] != '\n') {
            return print(fmt ++ "\n", args);
        }

        return print(fmt, args);
    }

    pub fn print(comptime fmt: string, args: anytype) void {
        if (isWasm) {
            source.stream.seekTo(0) catch return;
            source.stream.writer().print(fmt, args) catch return;
            const root = @import("root");
            root.console_log(root.Uint8Array.fromSlice(source.out_buffer[0..source.stream.pos]));
        } else {
            std.fmt.format(source.stream.writer(), fmt, args) catch unreachable;
        }
    }

    pub fn printErrorln(comptime fmt: string, args: anytype) void {
        if (fmt[fmt.len - 1] != '\n') {
            return printError(fmt ++ "\n", args);
        }

        return printError(fmt, args);
    }

    pub fn errorLn(comptime fmt: string, args: anytype) void {
        return printErrorln(fmt, args);
    }

    pub fn printError(comptime fmt: string, args: anytype) void {
        if (isWasm) {
            source.error_stream.seekTo(0) catch return;
            source.error_stream.writer().print(fmt, args) catch unreachable;
            const root = @import("root");
            root.console_error(root.Uint8Array.fromSlice(source.err_buffer[0..source.error_stream.pos]));
        } else {
            std.fmt.format(source.error_stream.writer(), fmt, args) catch unreachable;
        }
    }
};

pub const Global = struct {
    pub fn panic(comptime fmt: string, args: anytype) noreturn {
        if (isWasm) {
            Output.print(fmt, args);
            @panic(fmt);
        } else {
            std.debug.panic(fmt, args);
        }
    }

    pub fn notimpl() noreturn {
        Global.panic("Not implemented yet!!!!!", .{});
    }
};

pub const FileDescriptorType = if (isBrowser) u0 else std.os.fd_t;

// When we are on a computer with an absurdly high number of max open file handles
// such is often the case with macOS
// As a useful optimization, we can store file descriptors and just keep them open...forever
pub const StoredFileDescriptorType = if (isWindows or isBrowser) u0 else std.os.fd_t;