#############################################################################
# Some helpers to make step functions simpler.

import json
import logging
import os
import re
import subprocess
import time

import yaml


# Run a subprocess, capture its output and exit code in context.
def _run(ctx, argv, env):
    p = subprocess.Popen(argv, stdout=subprocess.PIPE, stderr=subprocess.PIPE, env=env)
    stdout, stderr = p.communicate("")
    ctx["argv"] = argv
    ctx["env"] = env
    ctx["stdout"] = stdout.decode("utf-8")
    ctx["stderr"] = stderr.decode("utf-8")
    ctx["exit"] = p.returncode


# Return argv prefix to run contractor from source directory. This
# ignores any config from the user running the test program, but gets
# the address of the manager VM from CONTRACTOR_ADDRESS in the
# environment.
def _contractor():
    return [os.path.join(srcdir, "contractor")]


# Return manager address.
def _manager_address():
    filename = os.path.join(srcdir, "test.address")
    addr = open(filename).read().strip()
    logging.debug("Manager address from %s is %r", filename, addr)
    return addr


# Create a config file for Contractor. Return its filename.
def _create_config(ctx):
    filename = "config.yaml"
    if ctx.get("config") is None:
        ctx["config"] = {"manager_address": _manager_address(), "verbose": True}
        with open(filename, "w") as f:
            yaml.safe_dump(ctx["config"], stream=f)
        logging.debug("config file: %r", open(filename).read())
    return filename


# Create dict with environment variables for running Contractor, merging
# os.environ and srcdir/test.env.
def _create_env():
    env = dict(os.environ)
    for line in open(os.path.join(srcdir, "test.env")):
        name, value = line.split("=", 1)
        env[name] = value.strip()
    return env


#############################################################################
# The actual step functions.

# Do nothing. Useful to have bindings that are recognized, but don't
# actually do anything.
def nop(ctx, **kwargs):
    pass


# Check that we can access the contractor VM.
# FIXME: this hardcodes some things.
def contractor_is_working(ctx):
    config = _create_config(ctx)
    argv = _contractor() + ["-c", config, "status"]
    _run(ctx, argv, _create_env())
    assert_eq(ctx["exit"], 0)


# Create a file from the files embedded in the input document.
def create_file(ctx, filename=None):
    with open(filename, "wb") as f:
        f.write(get_file(filename))


# Check that a file exists.
def file_exists(ctx, filename=None):
    assert_eq(os.path.exists(filename), True)


# Copy a file from srcdir.
def copy_file_from_srcdir(ctx, filename=None):
    shutil.copy(os.path.join(srcdir, "./" + filename), ".")


# Check that the subprocess we last ran ended with the expected exit
# code.
def exit_code_is(ctx, exit_code=None):
    assert_eq(ctx["exit"], int(exit_code))


# Run contractor dump
def run_contractor_dump(ctx, filename=None):
    argv = _contractor() + ["dump", filename]
    _run(ctx, argv, _create_env())


# Run the contractor to do a build.
def run_contractor_build(ctx, filename=None):
    config = _create_config(ctx)
    argv = _contractor() + ["-c", config, "build", filename]
    _run(ctx, argv, _create_env())


# Parse stdout from latest subprocess as JSON into a dict. Read the
# named YAML file, parse as a dict. Do the two dicts match?
def stdout_json_matches_yaml_file(ctx, filename=None):
    dict1 = json.loads(ctx["stdout"])
    with open(filename) as f:
        dict2 = yaml.safe_load(f)
    assert_eq(dict1, dict2)