#!/usr/bin/python

from __future__ import print_function
from argparse import ArgumentParser, RawTextHelpFormatter
import os
import os.path
import platform
import re
import subprocess
import sys
import time
import glob

winsfx = ".exe"
testsfx = "_test.cpp"


def processCLIArgs():
    """
    Define and process the command line interface to the runTests.py script.
    """
    cli_description = "Generate and run stan math library tests."
    cli_epilog = "See more information at: https://github.com/stan-dev/stan"

    parser = ArgumentParser(
        description=cli_description,
        epilog=cli_epilog,
        formatter_class=RawTextHelpFormatter,
    )

    # Now define all the rules of the command line args and opts
    parser.add_argument(
        "-j", metavar="N", type=int, default=1, help="number of cores for make to use"
    )

    tests_help_msg = "The path(s) to the test case(s) to run.\n"
    tests_help_msg += "Example: 'src/test/unit', 'src/test/integration', and/or\n"
    tests_help_msg += "         'src/test/unit/version_test'"
    parser.add_argument("tests", nargs="+", type=str, help=tests_help_msg)
    parser.add_argument(
        "-m",
        "--make-only",
        dest="make_only",
        action="store_true",
        help="Don't run tests, just try to make them.",
    )
    # And parse the command line against those rules
    return parser.parse_args()


def stopErr(msg, returncode):
    """Report an error message to stderr and exit with a given code."""
    sys.stderr.write("%s\n" % msg)
    sys.stderr.write("exit now (%s)\n" % time.strftime("%x %X %Z"))
    sys.exit(returncode)


def isWin():
    return platform.system().lower().startswith(
        "windows"
    ) or os.name.lower().startswith("windows")


batchSize = 24 if isWin() else 200


def mungeName(name):
    """Set up the makefile target name"""
    if name.startswith("src") or name.startswith("./src"):
        name = name.replace("src/", "", 1)
    if name.endswith(testsfx):
        name = name.replace(testsfx, "_test")
        if isWin():
            name += winsfx
            name = name.replace("\\", "/")
    return name


def doCommand(command, exit_on_failure=True):
    """Run command as a shell command and report/exit on errors."""
    print("------------------------------------------------------------")
    print("%s" % command)
    if isWin() and command.startswith("make "):
        command = command.replace("make ", "mingw32-make ")
    p1 = subprocess.Popen(command, shell=True)
    p1.wait()
    if exit_on_failure and (not (p1.returncode is None) and not (p1.returncode == 0)):
        stopErr("%s failed" % command, p1.returncode)


def modelDependencies(tests):
    dependencies = []
    for filepath in tests:
        filepath = "src/" + filepath + ".cpp"
        if os.path.isfile(filepath) and filepath.endswith(testsfx):
            with open(filepath) as file:
                test_file_content = file.read()
                # look for TEST() and TEST_F()
                matches = re.findall(
                    r"#include <test/test-models/.*hpp>", test_file_content
                )
                for x in matches:
                    x = x.replace("#include <", "").replace(">", "")
                    dependencies.append(x)
    return dependencies


def makeTest(name, j):
    """Run the make command for a given single test."""
    doCommand("make -j%d %s" % (j or 1, name))


def runTest(name):
    executable = mungeName(name).replace("/", os.sep)
    xml = mungeName(name).replace(winsfx, "")
    command = '%s --gtest_output="xml:%s.xml"' % (executable, xml)
    doCommand(command)

def files_in_folder(folder):
    """Returns a list of files in the folder and all
    its subfolders recursively. The folder can be
    written with wildcards as with the Unix find command.
    """
    files = []
    for f in glob.glob(folder):
        if os.path.isdir(f):
            files.extend(files_in_folder(f + os.sep + "**"))
        else:
            files.append(f)
    return files

def findTests(base_path):
    files = []
    for test_path in base_path:
        files.extend(files_in_folder(test_path))
    tests = [f for f in files if f.endswith(testsfx)]
    return list(map(mungeName, tests))

def batched(tests):
    return [tests[i : i + batchSize] for i in range(0, len(tests), batchSize)]


def main():
    inputs = processCLIArgs()

    tests = findTests(inputs.tests)
    if not tests:
        stopErr("No matching tests found.", -1)

    for batch in batched(tests):
        modelHpp = modelDependencies(batch)
        if len(modelHpp) > 0:
            makeTest(" ".join(modelHpp), inputs.j)
        makeTest(" ".join(batch), inputs.j)

    if not inputs.make_only:
        for t in tests:
            runTest(t)


if __name__ == "__main__":
    main()