#!/usr/bin/python3
import json
import os
import sys
import subprocess
from PIL import Image

if len(sys.argv) != 2:
    print("Usage:")
    print("./validate-spice uuid")
    print("./validate-spice --all")
    sys.exit(1)

SPICE_TYPE="desklet"

class CheckError(Exception):
    pass

# function with checks for an xlet
def validate_xlet(uuid):
    valid = False
    os.chdir(uuid)

    try:
        # Check mandatory files
        for file in ["info.json", "screenshot.png", "files/%s/metadata.json" % uuid, "files/%s/icon.png" % uuid]:
            if not os.path.exists(file):
                raise CheckError("[%s] Missing file: %s" % (uuid, file))

        found = False
        for root, dirs, files in os.walk("files/%s" % uuid):
            if any(ext.endswith(".po") for ext in files) and not any(ext.endswith(".pot") for ext in files):
                raise CheckError("[%s] Invalid location for translation files!" % (uuid))
            for file in files:
                if file == "%s.js" % SPICE_TYPE:
                    found = True
        if not found:
            raise CheckError("[%s] Missing main %s.js" % (uuid, SPICE_TYPE))

        # Check forbidden files
        for file in ["icon.png"]:
            if os.path.exists(file):
                raise CheckError("[%s] Forbidden file: %s" % (uuid, file))

        # Check mandatory directories
        for directory in ["files", "files/%s" % uuid]:
            if not os.path.isdir(directory):
                raise CheckError("[%s] Missing directory: %s" % (uuid, directory))

        # Check that there are no files in files other than the uuid directory
        if len(os.listdir("files")) != 1:
            raise CheckError("[%s] The files directory should ONLY contain the $uuid directory!" % (uuid))

        # check info.json
        with open("info.json") as file:
            try:
                info = json.load(file)
            except Exception as e:
                raise CheckError("Could not parse info.json: %s" % e)

            # check mandatory fields
            for field in ['author']:
                if field not in info:
                    raise CheckError("[%s] Missing field '%s' in info.json" % (uuid, field))

        # check metadata.json
        with open("files/%s/metadata.json" % uuid) as file:
            try:
                metadata = json.load(file)
            except Exception as e:
                raise CheckError("Could not parse metadata.json: %s" % e)

            # check forbidden fields
            for field in ['icon', 'dangerous', 'last-edited']:
                if field in metadata:
                    raise CheckError("[%s] Forbidden field '%s' in %s" % (uuid, field, "files/%s/metadata.json" % uuid))

            # check mandatory fields
            for field in ['uuid', 'name', 'description']:
                if field not in metadata:
                    raise CheckError("[%s] Missing field '%s' in %s" % (uuid, field, "files/%s/metadata.json" % uuid))

            # check uuid value
            if metadata['uuid'] != uuid:
                raise CheckError("[%s] Wrong uuid in %s" % (uuid, "files/%s/metadata.json" % uuid))

            # check for unicode characters in metadata
            for field in metadata:
                strvalue = str(metadata[field])
                if len(strvalue.encode()) != len(strvalue):
                    raise CheckError("[%s] Forbidden unicode characters in field '%s' in %s" % (uuid, field, "files/%s/metadata.json" % uuid))

        # check if icon is square
        im = Image.open("files/%s/icon.png" % uuid)
        (width, height) = im.size
        if width != height:
            raise CheckError("[%s] icon.png has to be square." % uuid)

        # check po and pot files
        podir = "files/%s/po" % uuid
        if os.path.isdir(podir):
            for file in os.listdir(podir):
                if file.endswith(".po"):
                    pocheck = subprocess.run(["msgfmt", "-c", os.path.join(podir, file), "-o", "-"], stdout=subprocess.DEVNULL, stderr=subprocess.PIPE, text=True)
                    if pocheck.stderr:
                        raise CheckError("[%s] The following errors were found in translation file '%s':\n%s"
                              "HINT: Most errors in translation file `%s` can usually be prevented and solved by using Poedit.\n"
                              % (uuid, file, pocheck.stderr, file)
                        )
                elif file.endswith(".pot"):
                    potcheck = subprocess.run(["xgettext", os.path.join(podir, file), "-o", "-"], stdout=subprocess.DEVNULL, stderr=subprocess.PIPE, text=True)
                    if potcheck.stderr:
                        raise CheckError("[%s] The following errors were found in translation template '%s':\n%s" % (uuid, file, potcheck.stderr))

        # Finally...
        valid = True
    except CheckError as error:
        print("[%s] Error during validation: %s" % (uuid, error))
    except Exception as error:
        print("[%s] Unknown error. %s" % (uuid, error))

    os.chdir("..")
    return valid

def quit(valid):
    if (valid):
        print ("No errors found. Everything looks good.")
        sys.exit(0)
    else:
        print ("\nErrors were found! Once you fix the issue, please re-run "
               "'validate-spice <uuid>'' to check for further errors.")
        sys.exit(1)

if sys.argv[1] == "--all":
    valid = True
    for uuid in os.listdir("."):
        if os.path.isdir(uuid) and not uuid.startswith("."):
            valid = validate_xlet(uuid) and valid
else:
    valid = validate_xlet(sys.argv[1])

quit(valid)