import hashlib
import json
import os
import threading
import time
import engine
import requests
import uuid
import subprocess
import socket
import shutil
from pathlib import Path
from fastapi import FastAPI, Request, File, UploadFile
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import FileResponse
from pydantic import BaseModel

devs = {
    "Matej Justus": {
        "git": "https://github.com/UntriexTv", "mail": "maco.justus@gmail.com"
    },
    "Benjamin Kojda": {
        "git": "https://github.com/Tucan444", "mail": "ben4442004@gmail.com"
    },
    "Jakub Ďuriš": {
        "git": "https://github.com/ff0082", "mail": "jakub1.duris@gmail.com"
    },
    "Samuel Šubika": {
          "git": "https://github.com/JustSteel", "mail": "SteelSamko2000@gmail.com"}
}
check = engine.Scan()
check.check_to_go()
if check.state_list["error"]:
    for error in check.errors:
        print(error)
    check.fix_version()

with open("settings.json", "r", encoding='utf-8') as f:  # loading settings
    settings = json.load(f)

with open("filesystem.json", "r", encoding='utf-8') as f:  # loading filesystem
    filesystem = json.load(f)


if settings["clear_cache_on_startup"]:
    shutil.rmtree("cache")
    os.mkdir("cache")


def get_my_ip():
    s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    s.connect(("8.8.8.8", 80))
    ip = s.getsockname()[0]
    s.close()
    return ip


IP = get_my_ip()
ID = filesystem["ID"]
location = filesystem["location"]
time_to_save = settings["time_to_save"]
app = FastAPI()  # init of FastAPI

origins = ["*", ]
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)
log = engine.Log(settings["log"])  # init of LOG
update = engine.Update()
offline = []
save_time = time.time()

time_to_heartbeat = settings["time_to_heartbeat"]  # Raspberry will be requesting heartbeat every __ seconds
time_to_heartbeat_offline = settings[
    "time_to_heartbeat_offline"]  # Raspberry will be requesting heartbeat every __ seconds from offline rpi

# json variables
heartbeat_table = settings["heartbeat_table"]
sensors = {}

messages = []  # {user: "", timestamp: time.Time(), message: ""}
if ID not in heartbeat_table["ID"]:
    heartbeat_table["ID"].append(ID)
    heartbeat_table["IP"].append(IP)
    heartbeat_table["location"].append(location)
    heartbeat_table["file_system"].append(filesystem)
    heartbeat_table["last_heartbeat"].append(time_to_heartbeat)


class ServerTable(BaseModel):  # table of content for heartbeat request
    ID: list
    IP: list
    location: list
    file_system: list
    last_heartbeat: list


class Sensor(BaseModel):
    name: str
    value: str


class Message(BaseModel):
    m_sender: str
    message: str


@app.get("/")
def read_root():
    return "wikispot"


@app.post("/heartbeat")
def heartbeat(s_table: ServerTable, request: Request):
    log.message(f"server requested heartbeat {request.client.host}:{request.client.port}")
    log.debug(f"Recieved server table: {s_table}")

    try:
        for position, server_id in enumerate(s_table.ID):
            if server_id in heartbeat_table["ID"]:
                if heartbeat_table["last_heartbeat"][heartbeat_table["ID"].index(server_id)] < \
                        s_table.last_heartbeat[position]:
                    heartbeat_table["last_heartbeat"][heartbeat_table["ID"].index(server_id)] = s_table.last_heartbeat[
                        position]
                    log.debug(f"updated {server_id}`s heartbeat to     {s_table.last_heartbeat[position]}")
                    heartbeat_table["file_system"][heartbeat_table["ID"].index(server_id)] = s_table.file_system[
                        position]
            elif server_id == ID:
                log.debug(f"Updated my heartbeat from {s_table.last_heartbeat[position]} to {time_to_heartbeat}")
                heartbeat_table["last_heartbeat"][heartbeat_table["ID"].index(ID)] = time_to_heartbeat
            else:
                log.message(f"Heartbeat from new server:\n        ID: {server_id} IP: {request.client}")
                heartbeat_table["ID"].append(int(s_table.ID[position]))
                heartbeat_table["IP"].append(s_table.IP[position])
                heartbeat_table["location"].append(s_table.location[position])
                heartbeat_table["file_system"].append(s_table.file_system[position])
                heartbeat_table["last_heartbeat"].append(int(s_table.last_heartbeat[position]))
                log.debug(f"Created {server_id}`s heartbeat:    {s_table.last_heartbeat[position]}")
    except Exception as error:
        log.error(f"heartbeat > {error}")

    if heartbeat_table["ID"][heartbeat_table["IP"].index(request.client.host)] in offline:
        offline.remove(heartbeat_table["ID"][heartbeat_table["IP"].index(request.client.host)])
        log.warning(f"{request.client.host} gone online")

    return heartbeat_table, {"ID": ID, "file_system": filesystem, "location": location}


@app.get("/{IDx}/sensors")
def get_sensors(IDx: int, request: Request):
    global sensors
    if IDx == ID:
        log.debug(f"Sensor data sent to {request.client.host} :\n    {sensors}")
        return sensors
    else:
        try:
            r = requests.get(f"""http://{heartbeat_table["IP"][heartbeat_table["ID"].index(IDx)]}:8000/{IDx}/sensors""")
            log.debug(f"Sensor data from {IDx} sent to {request.client.host} :\n    {r.json()}")
            return r.json()
        except Exception as error:
            log.error(f"Sensor data download from {IDx} failed.\n ERROR: {error}")
            return f"Sensor data download from {IDx} failed.\n ERROR: {error}"


@app.get("/files/{IDx}/{file}")
def get_file(IDx: int, file: str, request: Request):
    log.debug(f"""{request.client} requested {file} from {"this server" if IDx == ID else f"id {IDx}"}""")
    server_ip = heartbeat_table["IP"][heartbeat_table["ID"].index(IDx)]
    if IDx == ID:
        if os.path.isfile(f"files/{file}"):
            return FileResponse(f"files/{file}")
        else:
            log.warning(f"{request.client} tried to access file ({file}) that does not exist on this server.")
            return f"ERROR: File {file} does not exist."
    if IDx not in heartbeat_table["ID"]:
        log.warning(f"{request.client} tried to access id ({IDx}) that does not exist.")
        return f"ERROR: {IDx} does not exist."
    else:
        if os.path.isdir(f"cache/{IDx}"):
            if os.path.isfile(f"cache/{IDx}/{file}"):
                with open(f"cache/{IDx}/{file}", "rb") as compared_file:
                    m = hashlib.md5()
                    for line in compared_file:
                        m.update(line)
                rr = requests.get(f"""http://{server_ip}:8000/compare/{file}""")
                if rr.text.strip('"') != str(m.hexdigest()):
                    log.warning(f"{file} on server {server_ip} is changed.")
                else:
                    log.debug(f"returning cached file cache/{IDx}{file}")
                    return FileResponse(f"cache/{IDx}/{file}")
        elif sum(file.stat().st_size for file in Path("cache").rglob('*'))/1024**2 > settings["cache_size_mb"]:
            shutil.rmtree("cache")
            os.mkdir("cache")
            log.message(f"""Clearing cache, because of limit of {settings["cache_size_mb"]}MB""")
            os.mkdir(f"cache/{IDx}")
        else:
            os.mkdir(f"cache/{IDx}")
        r = requests.get(f"http://{server_ip}:8000/files/{IDx}/{file}")
        if "does not exist" in r.text:
            log.warning(f"{request.client} tried to access file ({file}) on id {IDx} that does not exist.")
            return f"ERROR: {file} does not exist."
        log.message(f"Downloaded {file} from {server_ip}")
        with open(f"cache/{IDx}/{file}", "wb") as save:
            save.write(bytes(r.content))
        return FileResponse(f"cache/{IDx}/{file}")


@app.post("/{IDx}/update_sensor")
def update_sensors(data: Sensor, request: Request, IDx: int):
    global sensors
    if IDx == ID:
        if data.name in sensors:
            if not data.value:
                log.message(f"{request.client.host} removed sensor {data.name}")
                del sensors[data.name]
            else:
                log.message(f"{request.client.host} updated sensor {data.name} with value {data.value}")
                sensors[data.name] = data.value
        else:
            log.warning(f"{request.client} created new sensor.\n SENSOR: {data}")
            sensors[data.name] = data.value
            return f"Successfuly made new sensor"
    else:
        r = requests.post(f"""http://{heartbeat_table["IP"][heartbeat_table["ID"].index(IDx)]}:8000/{IDx}/update_sensor""",
                          json={"name": data.name, "value": data.value})
        return r.text


@app.get("/compare/{file}")
def comparision(file: str):
    try:
        with open(f"files/{file}", "rb") as compared_file:
            m = hashlib.md5()
            for line in compared_file:
                m.update(line)
        return m.hexdigest()
    except FileNotFoundError:
        return f"ERROR {file} does not exist"


@app.get("/devices_list")
def get_devices_list():
    returning_value = [{"connected_id": ID}, *heartbeat_table["file_system"]]
    while "" in returning_value:
        returning_value.remove("")
    return returning_value


@app.get("/admin/get/{command}")
def admin_get(command: str, request: Request):
    log.message(f"{request.client} used admin command.")
    if command == "get_updates":
        return [update.get_version(), update.get_updates()]
    if "update-" in command:
        state = []
        version = command.split("-")[1]
        for rpi in heartbeat_table["IP"]:
            if rpi != IP:
                r = requests.get(f"""http://{rpi}:8000/admin/get/update_one-{version}""")
                if r.text.strip('"').split("\\n")[0] == "SUCCESS":
                    log.message(f"{rpi} was updated to {version}")
                else:
                    log.error(f"""{rpi} failed to update. Manual update may be needed for proper working of network.
                    Response from server: {r.text}""")
                state.append({rpi: r.text.strip('"').split("\\n")})
        subprocess.check_output(f"""python3 system.py update -version {version}""")
        log.message(f"All devices in network should be updated to {version}")
        state.append({IP: "updated"})
        return state
    if "update_one-" in command:
        state = subprocess.check_output(["python3", "system.py", "update", "-version", f"""{command.split("-")[1]}"""])
        log.message(state.decode("utf-8"))
        return state.decode("utf-8")
    if command == "heartbeat_table":
        return heartbeat_table
    if command == "filesystem":
        return filesystem


@app.post("/admin/{id_server}/upload_file")
async def create_upload_file(id_server: int, uploaded_file: UploadFile = File(...), patch: str = ""):
    file_location = f"{patch}{uploaded_file.filename}"
    if id_server == ID:
        with open(file_location, "wb+") as file_object:
            file_object.write(uploaded_file.file.read())
    else:
        with open(f"cache/{uploaded_file.filename}", "wb+") as file_object:
            file_object.write(uploaded_file.file.read())
        file = open(f"cache/{uploaded_file.filename}", "rb")
        requests.post(f"""http://{heartbeat_table["IP"][heartbeat_table["ID"].index(id_server)]}:8000/admin/{id_server}/upload_file""",
                      files={"uploaded_file": file, "patch": patch})
        file.close()
    return {"info": f"""file '{uploaded_file.filename}' saved at '{id_server}/{file_location}'"""}


@app.get("/messages/get")
def get_messages(timestamp: str = None):
    if timestamp:
        for position, message in enumerate(reversed(messages)):
            if float(message["timestamp"]) <= float(timestamp):
                return list(reversed(list(reversed(messages))[:position]))

        if timestamp == "0":
            return messages
        return []
    else:
        return messages[:10]


@app.get("/messages/register")
def register():
    return [uuid.uuid4().hex[24:], messages[:9]]


@app.get("/discovery")
def discovery():
    return "Success"


@app.post("/messages/post")
def post_messages(data: Message):
    log.debug(f"Message was posted. Sender: {data.m_sender}\n MESSAGE: {data.message}")
    if len(messages) >= settings["max_mess"]:
        del messages[:len(messages) - settings["max_mess"]]
    if data.m_sender and data.message:
        messages.append({"sender": data.m_sender, "message": data.message, "timestamp": time.time()})
        return "successful"
    else:
        return "Empty message/sender"


def send_heartbeat(ip, id):
    global heartbeat_table
    log.message(f"""sending heartbeat to {ip}({"offline" if id in offline else "online"})""")
    cache_request = requests.post(f"http://{ip}:8000/heartbeat", data=json.dumps(heartbeat_table))
    heartbeat_table = dict(cache_request.json()[0])
    log.debug(json.dumps(cache_request.json(), indent=4))


def mainloop():
    global save_time
    while True:
        for device_number, device_ID in enumerate(heartbeat_table["ID"]):
            if device_ID != ID:
                if int(heartbeat_table["last_heartbeat"][device_number]) < 0:
                    try:
                        send_heartbeat(heartbeat_table["IP"][device_number], heartbeat_table["ID"][device_number])
                    except requests.exceptions.ConnectionError:
                        if heartbeat_table["ID"][device_number] not in offline:
                            log.warning(f"""{heartbeat_table["IP"][device_number]} disconnected/is not available""")
                            offline.append(heartbeat_table["ID"][device_number])
                            heartbeat_table["last_heartbeat"][int(device_number)] = int(time_to_heartbeat_offline)
                        else:
                            offline.remove(heartbeat_table["ID"][device_number])
                            log.message(f"""Removing {device_ID} because of long inactivity.""")
                            del heartbeat_table["ID"][device_number]
                            del heartbeat_table["IP"][device_number]
                            del heartbeat_table["location"][device_number]
                            del heartbeat_table["file_system"][device_number]
                            del heartbeat_table["last_heartbeat"][device_number]
                    else:
                        if heartbeat_table["ID"][device_number] in offline:
                            offline.remove(heartbeat_table["ID"][device_number])
                            log.message(f"""{heartbeat_table["IP"][device_number]} gone online""")
                        heartbeat_table["last_heartbeat"][int(device_number)] = int(time_to_heartbeat) + 5
                try:
                    log.debug(
                        f"""{device_ID} : time to heartbeat : {heartbeat_table["last_heartbeat"][device_number]}""")
                    heartbeat_table["last_heartbeat"][device_number] = int(heartbeat_table["last_heartbeat"][device_number]) - 1
                except IndexError:
                    pass
            if time.time() - time_to_save > save_time and settings["save_table"]:
                save_time = time.time()
                log.message("Saving heartbeat table.")
                log.debug(f"Saving heartbeat table: {heartbeat_table}")
                settings["heartbeat_table"] = heartbeat_table
                with open("settings.json", "w", encoding='utf-8') as file:
                    json.dump(settings, file, indent=2)
        time.sleep(1)


print(f"""Starting WikiSpot V{update.get_version()["version"]} on http://{IP}:8000""")
print("GitHub: https://github.com/Tucan444/Mabasej_Team")
print("Developers of this project: ")
for dev in devs:
    print(f"""{dev}, GitHub: {devs[dev]["git"]}, mail: {devs[dev]["mail"]}""")
thread_1 = threading.Thread(target=mainloop, daemon=True)
thread_1.start()