#!/usr/bin/env python3
"""
A bowtie runner which always gets the right answer, slowly.
"""
from dataclasses import dataclass
import io
import json
import os
import shlex
import sys
import time


class Crash(Exception):
    """
    Self-immolation.
    """


_VALID = {"1": {"valid": True}, "0": {"valid": False}}


@dataclass
class Runner:

    _started: bool = False
    _stdout: io.TextIOWrapper = sys.stdout
    _hang_on_stop = False

    def run(self, stdin=sys.stdin):
        for line in stdin:
            each = json.loads(line)
            cmd = each.pop("cmd")
            getattr(self, f"cmd_{cmd}")(**each)

    def send(self, **response):
        self._stdout.write(f"{json.dumps(response)}\n")
        self._stdout.flush()

    def cmd_start(self, version):
        if os.environ.get("ENVSONSCHEMA_CRASH") == "1":
            raise Crash()

        assert version == 1
        self._started = True
        self.send(
            ready=True,
            version=1,
            implementation=dict(
                language="python",
                name="envsonschema",
            ),
        )

    def cmd_run(self, case, seq):
        assert self._started, "Not started!"

        send = self.send
        for instruction, arg in instructions(case["description"]):
            if instruction == "crash":
                raise Crash()
            elif instruction == "sleep":
                time.sleep(float(arg))
            elif instruction == "hang":
                self._hang_on_stop = True
            elif instruction == "error":
                result = dict(
                    (each.split("=", 1) for each in arg.split(",")),
                    errored=True,
                    seq=seq,
                )
                return self.send(**result)
            elif instruction == "skip":
                result = dict(
                    (each.split("=", 1) for each in arg.split(",")),
                    skipped=True,
                    seq=seq,
                )
                return self.send(**result)
            elif instruction == "split":
                def send(**response):
                    dumped = json.dumps(response)
                    size = len(dumped) // 2
                    self._stdout.write(dumped[:size])
                    self._stdout.flush()
                    time.sleep(0.1)
                    self._stdout.write(dumped[size:])
                    self._stdout.flush()
                    time.sleep(0.1)
                    self._stdout.write("\n")
                    self._stdout.flush()

        results = {"results": []}
        for test in case["tests"]:
            result = {"valid": False}

            for instruction, arg in instructions(test["description"]):
                if instruction == "crash":
                    raise Crash()
                elif instruction == "sleep":
                    time.sleep(float(arg))

                if instruction == "valid":
                    result = _VALID.get(arg, {"valid": arg})
                elif instruction == "skip":
                    result = dict(each.split("=", 1) for each in arg.split(","))
                    result.update(skipped=True)
                elif instruction == "error":
                    result = dict(
                        (each.split("=", 1) for each in arg.split(",")),
                        errored=True,
                        seq=seq,
                    )
                    return self.send(**result)

            results["results"].append(result)

        send(seq=seq, **results)

    def cmd_stop(self):
        assert self._started, "Not started!"
        if not self._hang_on_stop:
            sys.exit(0)


def instructions(description):
    words = (word.partition(":") for word in shlex.split(description))
    return ((instruction, arg) for instruction, colon, arg in words if colon)


Runner().run()
