#! /usr/bin/python3

import re
import sys
import glob
import os.path
import subprocess

from PIL import Image
from PIL import ImageChops

def imgequal(ref, out):
    ref = Image.open(ref).convert("1")
    out = Image.open(out).convert("1")

    diff = ImageChops.difference(ref, out)
    return diff.getbbox() is None

def readable_cmd(cmd):
    result = ""

    for arg in cmd:
        if " " not in arg and "'" not in arg and '"' not in arg:
            a = arg
        elif "'" not in arg:
            a = "'" + arg  + "'"
        else:
            a = a.replace(" ", "\\ ").replace("'", "\\'").replace('"', '\\"')

        result += " " + arg

    return result.strip()

def indent(str, n):
    return re.subn(r"^", " " * n, str, flags=re.MULTILINE)[0]

def runtest(program, refout=None, refimg=None, kind="script"):
    kind = "-u" if kind == "url" else "-s"
    cmd = "./fx92.py --quiet --save=/tmp/fx92-test.bmp".split() \
          + [kind, program]
    st = subprocess.run(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)

    # Retrieve standard error
    stderr = ""
    if st.stderr:
        stderr = st.stderr.decode().strip("\n")
        stderr = indent(stderr, 4)

    if st.returncode != 0:
        print("\x1b[41;1mFAILED\x1b[0m", program)
        print("  " + readable_cmd(cmd))
        if stderr:
            print("  Standard error:")
            print(stderr)
        else:
            print("  Nothing on standard error")
        print("")
        return False

    success = True
    status = { "out": None, "img": None }

    if refout is not None:
        with open(refout, "rb") as fp:
            refout = fp.read()
        if st.stdout == refout:
            status["out"] = True
        else:
            status["out"] = (st.stdout, refout)
            success = False

    if refimg is not None:
        if imgequal(refimg, "/tmp/fx92-test.bmp"):
            status["img"] = True
        else:
            status["img"] = False
            success = False

    if status["out"] is None and status["img"] is None:
        print("PASSED", program)
    elif success:
        print("\x1b[43;1mPASSED\x1b[0m", program)
    else:
        print("\x1b[41;1mFAILED\x1b[0m", program)

    if status["out"] is None:
        print("  (No reference output)")
    elif status["out"] == True:
        print("  Output is correct.")
    else:
        print("  Incorrect output, got:")
        print(indent(status["out"][0], 4))
        print("  Expected:")
        print(indent(status["out"][1], 4))

    if status["img"] is None:
        print("  (No reference image)")
    elif status["img"] == True:
        print("  Image is correct.")
    else:
        print("  Image is incorrect!")

    if stderr:
        print("  Standard error:")
        print(stderr)

    print("")
    return success

def main():
    p1 = glob.glob("tests/*.txt")
    p2 = glob.glob("tests/contest2019/*.txt")
    paths = sorted(p1) + sorted(p2)
    print("Found {} tests.".format(len(paths)))

    total = 0
    passed = 0

    for t in paths:
        refout = t[:-4] + ".out"
        refout = refout if os.path.isfile(refout) else None

        refimg = t[:-4] + ".png"
        refimg = refimg if os.path.isfile(refimg) else None

        kind = "url" if t.startswith("tests/contest2019/") else "script"
        passed += runtest(t, refout=refout, refimg=refimg, kind=kind)
        total += 1

    if passed < total:
        print("\nWarning, some tests failed!")
        return 1
    return 0

if __name__ == "__main__":
    sys.exit(main())