from flask import Flask, request, jsonify, abort, Response
from cryptography.fernet import Fernet
from flask_api import status
from pathlib import Path
import string
import random
import os
import datetime

import settings  # app settings (such as allowed extensions)


ALPHANUMERIC = string.ascii_letters + string.digits  # uppercase, lowercase, and numbers

app = Flask(__name__)  # app is the app


def allowed_extension(testext):
    if testext in settings.ALLOWED_EXTENSIONS:
        return True
    else:
        return False


def generate_name(extension):
    namefound = False
    while not namefound:
        fname = ''.join((random.choice(ALPHANUMERIC) for i in range(8))) + str(extension)
        if not Path(fname).is_file():
            namefound = True
    return fname


def log_savelog(key, ip, savedname):
    if settings.SAVELOG_KEYPREFIX > 0:
        with open(settings.SAVELOG, "a+") as slogf:
            slogf.write("[{0}] {1}: {2} - {3}\n".format(datetime.datetime.now(), key[:settings.SAVELOG_KEYPREFIX], ip, savedname))
        os.chmod(settings.SAVELOG, settings.SAVELOG_CHMOD)
    else:
        with open(settings.SAVELOG, "a+") as slogf:
            slogf.write("[{0}] {1} - {2}\n".format(datetime.datetime.now(), ip, savedname))
        os.chmod(settings.SAVELOG, settings.SAVELOG_CHMOD)

@app.route("/upload", methods = ["POST"])
def upload():
    if request.method == "POST":  # sanity check: make sure it's a POST request
        print("Request method was POST!")

        os.chmod("uploadkeys", settings.UPLOADKEYS_CHMOD)
        with open(settings.ENCKEY_PATH,"rb") as enckey: # load encryption key
            key = enckey.read()
        f = Fernet(key)

        with open("uploadkeys", "rb") as keyfile:
            encrypted_data = keyfile.read()
        decrypted_data = str(f.decrypt(encrypted_data).decode('utf-8'))
        decrypted_data = decrypted_data.splitlines()

        validkeys = [x.strip("\n") for x in decrypted_data]
        while "" in validkeys:
            validkeys.remove("")
            print("Removed blank key(s)")
        print("Loaded validkeys")
        if "uploadKey" in request.form:  # if an uploadKey was provided
            if request.form["uploadKey"] in validkeys:  # check if uploadKey is valid
                print("Key is valid!")

                if "imageUpload" in request.files:  # check if image to upload was provided
                    f = request.files["imageUpload"]  # f is the image to upload
                else:
                    print("No image upload was found!")
                    return jsonify({'status': 'error', 'error': 'NO_IMAGE_UPLOADED'}), status.HTTP_400_BAD_REQUEST

                if f.filename == "":  # make sure the filename isn't blank
                    print("Filename is blank")
                    return jsonify({'status': 'error', 'error': 'FILENAME_BLANK'}), status.HTTP_400_BAD_REQUEST

                fext = Path(f.filename).suffix  # get the uploaded extension
                if allowed_extension(fext):  # if the extension is allowed
                    print("Generating file with extension {0}".format(fext))
                    fname = generate_name(fext)  # generate file name
                    print("Generated name: {0}".format(fname))

                    if f:  # if the uploaded image exists
                        print("Uploaded image exists")
                        f.save(os.path.join(settings.UPLOAD_FOLDER, fname))  # save the image
                        print("Saved to {0}".format(fname))
                        url = settings.ROOTURL + fname  # construct the url to the image
                        if settings.SAVELOG != "/dev/null":
                            print("Saving to savelog")
                            log_savelog(request.form["uploadKey"], request.remote_addr, fname)
                        print("Returning json response")
                        return jsonify({'status': 'success', 'url': url, 'name': fname, 'uploadedName': f.filename}), status.HTTP_201_CREATED
                    else:  # this shouldn't happen
                        print("Um... uploaded image... is nonexistent? Please report this error!")
                        return jsonify({'status': 'error', 'error': 'UPLOADED_IMAGE_FAILED_SANITY_CHECK_1'}), status.HTTP_400_BAD_REQUEST

                else:  # if the extension was invalid
                    print("Uploaded extension is invalid!")
                    abort(415)

            else:  # if the key was not valid
                print("Key is invalid!")
                print("Request key: {0}".format(request.form["uploadKey"]))
                abort(401)

        else:  # if uploadKey was not found in request body
            print("No uploadKey found in request!")
            abort(401)


    else:  # if the request method wasn't post
        print("Request method was not POST!")
        abort(405)

if __name__ == "__main__":
    print("Run with `flask` or a WSGI server!")