import asyncio
import json
import os
import time
import sys
import zipfile

import aiohttp
import requests

from io import BytesIO
from typing import List, Dict
from collections import defaultdict

MINIMUM_PURGE_AGE = 9.75 * 24 * 60 * 60  # slightly less than 10 days
TIMEOUT = 10
SKIPPED_SERVICES = {"SHOWROOM", "Dacast"}
SERVICES_FILE = "plugins/rtmp-services/data/services.json"
PACKAGE_FILE = "plugins/rtmp-services/data/package.json"
CACHE_FILE = "other/timestamps.json"
GITHUB_OUTPUT_FILE = os.environ.get("GITHUB_OUTPUT", None)

DO_NOT_PING = {"jp9000"}
PR_MESSAGE = """This is an automatically created pull request to remove unresponsive servers and services.

| Service | Action Taken | Author(s) |
| ------- | ------------ | --------- |
{table}

If you are not responsible for an affected service and want to be excluded from future pings please let us know.

Created by workflow run: https://github.com/{repository}/actions/runs/{run_id}"""

# GQL is great isn't it
GQL_QUERY = """{
  repositoryOwner(login: "obsproject") {
    repository(name: "obs-studio") {
      object(expression: "master") {
        ... on Commit {
          blame(path: "plugins/rtmp-services/data/services.json") {
            ranges {
              startingLine
              endingLine
              commit {
                author {
                  user {
                    login
                  }
                }
              }
            }
          }
        }
      }
    }
  }
}"""


def get_last_artifact():
    s = requests.session()
    s.headers["Authorization"] = f'Bearer {os.environ["GITHUB_TOKEN"]}'

    run_id = os.environ["WORKFLOW_RUN_ID"]
    repo = os.environ["REPOSITORY"]

    # fetch run first, get workflow id from there to get workflow runs
    r = s.get(f"https://api.github.com/repos/{repo}/actions/runs/{run_id}")
    r.raise_for_status()
    workflow_id = r.json()["workflow_id"]

    r = s.get(
        f"https://api.github.com/repos/{repo}/actions/workflows/{workflow_id}/runs",
        params=dict(
            per_page=1,
            status="completed",
            branch="master",
            conclusion="success",
            event="schedule",
        ),
    )
    r.raise_for_status()
    runs = r.json()
    if not runs["workflow_runs"]:
        raise ValueError("No completed workflow runs found")

    r = s.get(runs["workflow_runs"][0]["artifacts_url"])
    r.raise_for_status()

    for artifact in r.json()["artifacts"]:
        if artifact["name"] == "timestamps":
            artifact_url = artifact["archive_download_url"]
            break
    else:
        raise ValueError("No previous artifact found.")

    r = s.get(artifact_url)
    r.raise_for_status()
    zip_data = BytesIO()
    zip_data.write(r.content)

    with zipfile.ZipFile(zip_data) as zip_ref:
        for info in zip_ref.infolist():
            if info.filename == "timestamps.json":
                return json.loads(zip_ref.read(info.filename))


def find_people_to_blame(raw_services: str, servers: list[tuple[str, str]]) -> dict:
    if not servers:
        return dict()

    # Fetch Blame data from github
    s = requests.session()
    s.headers["Authorization"] = f'Bearer {os.environ["GITHUB_TOKEN"]}'

    r = s.post(
        "https://api.github.com/graphql", json=dict(query=GQL_QUERY, variables=dict())
    )
    r.raise_for_status()
    j = r.json()

    # The file is only ~2600 lines so this isn't too crazy and makes the lookup very easy
    line_author = dict()
    for blame in j["data"]["repositoryOwner"]["repository"]["object"]["blame"][
        "ranges"
    ]:
        for i in range(blame["startingLine"] - 1, blame["endingLine"]):
            if user := blame["commit"]["author"]["user"]:
                line_author[i] = user["login"]

    service_authors = defaultdict(set)
    for i, line in enumerate(raw_services.splitlines()):
        if '"url":' not in line:
            continue
        for server, service in servers:
            if server in line and (author := line_author.get(i)):
                if author not in DO_NOT_PING:
                    service_authors[service].add(author)

    return service_authors


def set_output(name, value):
    if not GITHUB_OUTPUT_FILE:
        return

    try:
        with open(GITHUB_OUTPUT_FILE, "a", encoding="utf-8", newline="\n") as f:
            f.write(f"{name}={value}\n")
    except Exception as e:
        print(f"Writing to github output files failed: {e!r}")


async def check_servers_task(
    session: aiohttp.ClientSession, host: str, protocol: str, servers: List[str]
) -> List[Dict]:
    query = [dict(url=h, protocol=protocol) for h in servers]

    async with session.get(
        f"http://{host}:8999/test_remote_servers", json=query
    ) as resp:
        return await resp.json()


async def process_services(session: aiohttp.ClientSession, check_servers: List[str]):
    try:
        with open(SERVICES_FILE, encoding="utf-8") as services_file:
            raw_services = services_file.read()
            services = json.loads(raw_services)
        with open(PACKAGE_FILE, encoding="utf-8") as package_file:
            package = json.load(package_file)
    except OSError as e:
        print(f"❌ Could not open services/package file: {e}")
        return 1

    # attempt to load last check result cache
    try:
        with open(CACHE_FILE, encoding="utf-8") as check_file:
            fail_timestamps = json.load(check_file)
    except OSError as e:
        # cache might be evicted or not exist yet, so this is non-fatal
        print(
            f"⚠️ Could not read cache file, trying to get last artifact (Exception: {e})"
        )

        try:
            fail_timestamps = get_last_artifact()
        except Exception as e:
            print(f"⚠️ Could not fetch cache file, starting fresh. (Exception: {e})")
            fail_timestamps = dict()
        else:
            print("Fetched cache file from last run artifact.")
    else:
        print("Successfully loaded cache file:", CACHE_FILE)

    start_time = int(time.time())
    affected_services = dict()
    removed_servers = list()

    # create temporary new list
    new_services = services.copy()
    new_services["services"] = []

    for service in services["services"]:
        # skip services that do custom stuff that we can't easily check
        if service["name"] in SKIPPED_SERVICES:
            new_services["services"].append(service)
            continue

        service_type = service.get("recommended", {}).get("output", "rtmp_output")
        if service_type not in {"rtmp_output", "ffmpeg_hls_muxer"}:
            print("Unknown service type:", service_type)
            new_services["services"].append(service)
            continue

        protocol = "rtmp" if service_type == "rtmp_output" else "hls"

        # create a copy to mess with
        new_service = service.copy()
        new_service["servers"] = []

        # run checks for all the servers, and store results in timestamp cache
        try:
            servers = [s["url"] for s in service["servers"]]
            tasks = []
            for host in check_servers:
                tasks.append(
                    asyncio.create_task(
                        check_servers_task(session, host, protocol, servers)
                    )
                )
            results = await asyncio.gather(*tasks)
        except Exception as e:
            print(
                f"❌ Querying server status for \"{service['name']}\" failed with: {e}"
            )
            return 1

        # go over results
        for server, result in zip(service["servers"], zip(*results)):
            failure_count = sum(not res["status"] for res in result)
            probe_count = len(result)
            # only treat server as failed if all check servers reported a failure
            is_ok = failure_count < probe_count

            if not is_ok:
                failures = {res["comment"] for res in result if not res["status"]}
                print(
                    f"⚠️ Connecting to server failed: {server['url']} (Reason(s): {failures})"
                )

                if ts := fail_timestamps.get(server["url"], None):
                    if (delta := start_time - ts) >= MINIMUM_PURGE_AGE:
                        print(
                            f'🗑️ Purging server "{server["url"]}", it has been '
                            f"unresponsive for {round(delta/60/60/24)} days."
                        )
                        removed_servers.append((server["url"], service["name"]))
                        # continuing here means not adding it to the new list, thus dropping it
                        continue
                else:
                    fail_timestamps[server["url"]] = start_time
            elif is_ok and server["url"] in fail_timestamps:
                # remove timestamp of failed check if server is back
                delta = start_time - fail_timestamps[server["url"]]
                print(
                    f'💡 Server "{server["url"]}" is back after {round(delta/60/60/24)} days!'
                )
                del fail_timestamps[server["url"]]

            new_service["servers"].append(server)

        if (diff := len(service["servers"]) - len(new_service["servers"])) > 0:
            print(f'ℹ️ Removed {diff} server(s) from {service["name"]}')
            affected_services[service["name"]] = f"{diff} servers removed"

        # remove services with no valid servers
        if not new_service["servers"]:
            print(f'💀 Service "{service["name"]}" has no valid servers left, removing!')
            affected_services[service["name"]] = f"Service removed"
        else:
            new_services["services"].append(new_service)

        # wait a bit between services
        await asyncio.sleep(2.0)

    # write cache file
    try:
        os.makedirs("other", exist_ok=True)
        with open(CACHE_FILE, "w", encoding="utf-8") as cache_file:
            json.dump(fail_timestamps, cache_file)
    except OSError as e:
        print(f"❌ Could not write cache file: {e}")
        return 1
    else:
        print("Successfully wrote cache file:", CACHE_FILE)

    if removed_servers:
        # increment package version and save that as well
        package["version"] += 1
        package["files"][0]["version"] += 1

        try:
            with open(SERVICES_FILE, "w", encoding="utf-8") as services_file:
                json.dump(new_services, services_file, indent=4, ensure_ascii=False)
                services_file.write("\n")

            with open(PACKAGE_FILE, "w", encoding="utf-8") as package_file:
                json.dump(package, package_file, indent=4)
                package_file.write("\n")
        except OSError as e:
            print(f"❌ Could not write services/package file: {e}")
            return 1
        else:
            print(
                f"Successfully wrote services/package files:\n- {SERVICES_FILE}\n- {PACKAGE_FILE}"
            )

        # try to find authors to ping, this is optional and is allowed to fail
        try:
            service_authors = find_people_to_blame(raw_services, removed_servers)
        except Exception as e:
            print(f"⚠ Could not fetch blame for some reason: {e}")
            service_authors = dict()

        # set GitHub outputs
        set_output("make_pr", "true")
        msg = PR_MESSAGE.format(
            repository=os.environ["REPOSITORY"],
            run_id=os.environ["WORKFLOW_RUN_ID"],
            table="\n".join(
                "| {name} | {action} | {authors} |".format(
                    name=name.replace("|", "\\|"),
                    action=action,
                    authors=", ".join(
                        f"@{author}" for author in sorted(service_authors.get(name, []))
                    ),
                )
                for name, action in sorted(affected_services.items())
            ),
        )
        set_output("pr_message", json.dumps(msg))
    else:
        set_output("make_pr", "false")


async def main():
    # check for environment variables
    try:
        api_key = os.environ["API_KEY"]
        servers = os.environ["API_SERVERS"].split(",")
        if not servers:
            raise ValueError("No checker servers!")
        # Mask everything except the region code
        for server in servers:
            prefix = server[: server.index(".") + 1]
            print(f"::add-mask::{prefix}")
            suffix = server[server.index(".", len(prefix)) :]
            print(f"::add-mask::{suffix}")
    except Exception as e:
        print(f"❌ Failed getting required environment variables: {e}")
        return 1

    # create aiohttp session
    async with aiohttp.ClientSession() as session:
        session.headers["Authorization"] = api_key
        session.headers["User-Agent"] = "OBS Repo Service Checker/1.0"
        return await process_services(session, servers)


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