import io
import os
from dataclasses import dataclass, asdict
from itertools import combinations
from math import isnan
from typing import List, Iterable

import numpy as np
import scipy
from circleguard import Circleguard, ReplayString, Hit
from flask import Flask, request, jsonify, abort

from src.WriteStreamWrapper import WriteStreamWrapper

# Circleguard
cg = Circleguard(os.getenv("OSU_API_KEY"), db_path="./dbs/db.db", slider_dir="./dbs/")

app = Flask(__name__)


@dataclass
class ReplayRequest:
    replay_data: str
    mods: int
    beatmap_id: int

    @staticmethod
    def from_dict(data):
        try:
            return ReplayRequest(
                replay_data=data['replay_data'],
                mods=data['mods'],
                beatmap_id=int(data['beatmap_id'])
            )
        except (ValueError, KeyError, TypeError) as e:
            raise ValueError(f"Invalid data format: {e}")


# Data class for the response
@dataclass
class ReplayResponse:
    ur: float
    adjusted_ur: float
    frametime: float
    edge_hits: int
    snaps: int

    mean_error: float
    error_variance: float
    error_standard_deviation: float
    minimum_error: float
    maximum_error: float
    error_range: float
    error_coefficient_of_variation: float
    error_kurtosis: float
    error_skewness: float

    judgements: List[Hit]

    def to_dict(self):
        d = asdict(self)
        for key, value in d.items():
            if isinstance(value, float) and isnan(value):
                d[key] = None
        return d


@dataclass
class ScoreJudgement:
    time: float
    x: float
    y: float
    type: str
    distance_center: float
    distance_edge: float
    error: float


@app.post("/replay")
def process_replay():
    try:
        request_data = request.get_json()
        if not request_data:
            abort(400, description="Bad Request: No JSON data provided.")

        replay_request = ReplayRequest.from_dict(request_data)

        memory_stream1 = io.BytesIO()
        stream_wrapper1 = WriteStreamWrapper(memory_stream1, stream_is_closable=False)
        stream_wrapper1.write_osr_data2(replay_request.replay_data, replay_request.mods)
        stream_wrapper1.end()
        result_bytes1 = memory_stream1.getvalue()
        replay1 = ReplayString(result_bytes1)

        cg_beatmap = cg.library.lookup_by_id(beatmap_id=replay_request.beatmap_id, download=True, save=True)

        ur = cg.ur(replay=replay1, beatmap=cg_beatmap)
        adjusted_ur = cg.ur(replay=replay1, beatmap=cg_beatmap, adjusted=True)
        frametime = cg.frametime(replay=replay1)
        edge_hits = sum(1 for _ in cg.hits(replay=replay1, within=1, beatmap=cg_beatmap))
        snaps = sum(1 for _ in cg.snaps(replay=replay1, beatmap=cg_beatmap))

        hits: Iterable[Hit] = cg.hits(replay=replay1, beatmap=cg_beatmap)
        judgements: List[ScoreJudgement] = []
        for hit in hits:
            hit_obj = ScoreJudgement(
                time=float(hit.time),
                x=float(hit.x),
                y=float(hit.y),
                type=hit.type.name,
                distance_center=float(hit.distance(to='center')),
                distance_edge=float(hit.distance(to='edge')),
                error=float(hit.error())
            )
            judgements.append(hit_obj)

        errors = np.array([score.error for score in judgements])

        mean_error = np.mean(errors)
        error_variance = np.var(errors)
        error_std_dev = np.std(errors)
        min_error = np.min(errors)
        max_error = np.max(errors)
        error_range = max_error - min_error
        coefficient_of_variation = error_std_dev / mean_error if mean_error != 0 else None
        kurtosis = scipy.stats.kurtosis(errors)
        skewness = scipy.stats.skew(errors)

        ur_response = ReplayResponse(
            ur=ur,
            adjusted_ur=adjusted_ur,
            frametime=frametime,
            edge_hits=edge_hits,
            snaps=snaps,

            mean_error=mean_error,
            error_variance=error_variance,
            error_standard_deviation=error_std_dev,
            minimum_error=min_error,
            maximum_error=max_error,
            error_range=error_range,
            error_coefficient_of_variation=coefficient_of_variation,
            error_kurtosis=kurtosis,
            error_skewness=skewness,

            judgements=judgements
        )
        return jsonify(ur_response.to_dict())

    except ValueError as e:
        abort(400, description=str(e))


@dataclass
class ScoreSimilarity:
    replay_id_1: int
    replay_id_2: int

    similarity: float
    correlation: float


@dataclass
class ReplayDto:
    replayId: int
    replayMods: int
    replayData: str


@app.post("/similarity")
def process_similarity():
    try:
        request_data = request.get_json()
        if not request_data:
            abort(400, description="Bad Request: No JSON data provided.")

        replays: List[ReplayDto] = request_data['replays']
        replay_cache = {}
        response = []

        def get_or_create_replay(replay, cache):
            try:
                if replay['replayId'] not in cache:
                    memory_stream = io.BytesIO()
                    stream_wrapper = WriteStreamWrapper(memory_stream, stream_is_closable=False)
                    stream_wrapper.write_osr_data2(replay['replayData'], replay['replayMods'])
                    stream_wrapper.end()
                    result_bytes = memory_stream.getvalue()
                    cache[replay['replayId']] = ReplayString(result_bytes)
                return cache[replay['replayId']]
            except:
                return None

        for score1, score2 in combinations(replays, 2):
            if score1['replayId'] == score2['replayId']:
                continue

            replay1 = get_or_create_replay(score1, replay_cache)
            replay2 = get_or_create_replay(score2, replay_cache)

            if replay1 is None or replay2 is None:
                print('Error processing replay', flush=True)
                continue

            similarity = cg.similarity(replay1=replay1, replay2=replay2, method='similarity')
            correlation = cg.similarity(replay1=replay1, replay2=replay2, method='correlation')

            new_score_similarity = ScoreSimilarity(
                replay_id_1=score1['replayId'],
                replay_id_2=score2['replayId'],
                similarity=similarity,
                correlation=correlation
            )
            response.append(new_score_similarity)

        return jsonify({'result': response})

    except ValueError as e:
        abort(400, description=str(e))


if __name__ == "__main__":
    app.run(host='0.0.0.0', debug=False)