#!/usr/bin/env python

import sys
import subprocess
import threading
import os
from datetime import datetime

__FILENAME = ""

MAX_JOBS = max(1, len(os.sched_getaffinity(0)) - 2)
TS_VRB = 2
CWD = os.path.dirname(os.path.abspath(__file__))

BUILD_D = f"{CWD}/build"


def shift(arr):
    if not arr:
        return None  # or raise IndexError if you prefer
    return arr.pop(0)


def timestamp(dt=datetime.now(), fmt="hours"):
    return f"{dt.hour:0>2}:{dt.minute:0>2}:{dt.second:0>2}"


def run(*cmds, parallel=False, tag=None, interactive=False):
    threads = []

    def run_single(cmd, tag):
        env = os.environ.copy()
        env["MAKE_TERMOUT"] = "true"
        env["MAKE_TERMERR"] = "true"
        start_time = datetime.now()
        print(f"{f"{timestamp(start_time)} | " if TS_VRB > 0 else ""}CMD: {cmd}")
        with subprocess.Popen(
            cmd, shell=True,
            stdout=None if interactive else subprocess.PIPE,
            stderr=None if interactive else subprocess.STDOUT,
            # text=None if interactive else True,
        ) as proc:
            if not interactive:
                for line in proc.stdout:
                    dt = datetime.now()
                    if tag:
                        print(f"{f"{timestamp(dt)} | " if TS_VRB >
                              0 else ""}stdout ({tag}): ", flush=True, end='')
                    else:
                        print(f"{f"{timestamp(dt)} | " if TS_VRB >
                              0 else ""}stdout: ", flush=True, end='')
                    sys.stdout.buffer.write(line)
                    sys.stdout.buffer.flush()
            proc.wait()
            if proc.returncode != 0:
                print(f"ERROR: Command '{
                      cmd}' exited with code {proc.returncode}")
                exit(1)
    for i, command in enumerate(cmds):

        current_tag = tag if len(cmds) <= 1 else (
            f"{tag}-{i}" if tag else None)
        if parallel:
            t = threading.Thread(
                target=run_single, args=(command, current_tag))
            t.start()
            threads.append(t)
        else:
            run_single(command, current_tag)

    for t in threads:
        t.join()


def todo(reason):
    print(f"ERROR: Unimplemented {reason}")
    exit(1)


def cmd_configure(args):

    def cmd_help():
        print(f"Usage: {__FILENAME} configure [component]")
        print("Components:")
        print("  help    - Show this help")
        print("  kernel  - The linux kernel")
        print("  busybox - Busybox")

    # $(MAKE) -C $(MAKEFILE_DIR)/kernel O=$(KERNEL_BUILD_DIR) KCONFIG_CONFIG="$(MAKEFILE_DIR)/.kernel-config" menuconfig
    subc = shift(args)
    if not subc or subc == "help":
        cmd_help()
        exit(1)
    elif subc == "kernel":
        run(f"make -C {CWD}/linux/kernel O={BUILD_D}/linux/kernel KCONFIG_CONFIG='{
            CWD}/linux/.kernel-config' menuconfig", interactive=True)
    elif subc == "busybox":
        run(f"make -C {CWD}/linux/busybox O={BUILD_D}/linux/busybox KCONFIG_CONFIG='{
            CWD}/linux/.busybox-config' menuconfig", interactive=True)
    else:
        print(f"ERROR: Unknown component {subc}")
        cmd_help()
        exit(1)


def cmd_build(args):
    def cmd_help():
        print(f"Usage: {__FILENAME} build [component]")
        print("Components:")
        print("  help      - Show this help")
        print("  all       - Builds everything")
        print("  linux     - Everything bellow")
        print("    kernel  - The linux kernel")
        print("    busybox - Busybox")
        print("  rust      - Builds all of the rust components")
        print("  img       - Rebuilds the image")

    def build_init():
        run(
            f"mkdir -p {BUILD_D}/linux/kernel",
            f"mkdir -p {BUILD_D}/linux/busybox",
            parallel=True
        )

    def build_kernel(args):
        run(f"make -C {CWD}/linux/kernel O={BUILD_D}/linux/kernel KCONFIG_CONFIG='{
            CWD}/linux/.kernel-config' -j{MAX_JOBS}", tag="kernel")

    def build_busybox(args):
        run(
            f"cp {CWD}/linux/.busybox-config {
                BUILD_D}/linux/busybox/.config",
            f"make -C {CWD}/linux/busybox O={BUILD_D}/linux/busybox KCONFIG_CONFIG='{
                CWD}/linux/.busybox-config' -j{MAX_JOBS}",
            tag="busybox"
        )

    def build_rust(args):
        todo("build_rust")

    def build_image(args):
        # for the later bootable.img or whatever file
        todo("build_image")

    cmd = shift(args)

    if not cmd or cmd == "help":
        cmd_help()
        exit(1)
    elif cmd == "all":
        build_init()
        build_kernel(args)
        build_busybox(args)
        build_rust(args)
        build_image(args)
    elif cmd == "linux":
        build_init()
        build_kernel(args)
        build_busybox(args)
    elif cmd == "kernel":
        build_init()
        build_kernel(args)
    elif cmd == "busybox":
        build_init()
        build_busybox(args)
    elif cmd == "rust":
        build_init()
        build_rust(args)
    elif cmd == "img":
        build_init()
        build_image(args)
    else:
        print(f"ERROR: Unknown component '{cmd}'")
        cmd_help()
        exit(1)


AVAILABLE_SUBCOMMANDS = {
    "help": help,
    "configure": cmd_configure,
    "build": cmd_build
}


def help():
    print(f"Usage: {__FILENAME} [subcommand]")
    print("Subcommands:")
    print("  help      - Show this help")
    print("  configure - Configure components")
    print("  build     - Compile/build components")


if __name__ == "__main__":
    args = sys.argv
    __FILENAME = shift(args)

    cmd = shift(args)

    if not cmd:
        help()
        exit(1)

    cmd_v = AVAILABLE_SUBCOMMANDS[cmd]
    if not cmd_v:
        print(f"ERROR: Unknown subcommand '{cmd}'")
        help()
        exit(1)

    (cmd_v)(args)

    exit(0)