import 'dart:async';
import 'dart:convert';
import 'dart:core';
import 'dart:io';
import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;
import 'package:vikunja_app/api/response.dart';
import 'package:vikunja_app/components/string_extension.dart';
import 'package:vikunja_app/global.dart';

import '../main.dart';

class Client {
  GlobalKey<ScaffoldMessengerState>? global_scaffold_key;
  final JsonDecoder _decoder = new JsonDecoder();
  final JsonEncoder _encoder = new JsonEncoder();
  String _token = '';
  String _base = '';
  bool authenticated = false;
  bool ignoreCertificates = false;
  bool showSnackBar = true;

  String get base => _base;
  String get token => _token;

  String? post_body;

  bool operator ==(dynamic otherClient) {
    return otherClient._token == _token;
  }

  Client(this.global_scaffold_key,
      {String? token, String? base, bool authenticated = false}) {
    configure(token: token, base: base, authenticated: authenticated);
  }

  void reload_ignore_certs(bool? val) {
    ignoreCertificates = val ?? false;
    HttpOverrides.global = new IgnoreCertHttpOverrides(ignoreCertificates);
    if (global_scaffold_key == null ||
        global_scaffold_key!.currentContext == null) return;
    VikunjaGlobal.of(global_scaffold_key!.currentContext!)
        .settingsManager
        .setIgnoreCertificates(ignoreCertificates);
  }

  get _headers => {
        'Authorization': _token != '' ? 'Bearer $_token' : '',
        'Content-Type': 'application/json',
        'User-Agent': 'Vikunja Mobile App'
      };

  get headers => _headers;

  @override
  int get hashCode => _token.hashCode;

  void configure({String? token, String? base, bool? authenticated}) {
    if (token != null) _token = token;
    if (base != null) {
      base = base.replaceAll(" ", "");
      if (base.endsWith("/")) base = base.substring(0, base.length - 1);
      _base = base.endsWith('/api/v1') ? base : '$base/api/v1';
    }
    if (authenticated != null) this.authenticated = authenticated;
  }

  void reset() {
    _token = _base = '';
    authenticated = false;
  }

  Future<Response?> get(String url,
      [Map<String, List<String>>? queryParameters]) {
    Uri uri = Uri.tryParse('${this.base}$url')!;
    // why are we doing it like this? because Uri doesnt have setters. wtf.

    uri = Uri(
        scheme: uri.scheme,
        userInfo: uri.userInfo,
        host: uri.host,
        port: uri.port,
        path: uri.path,
        //queryParameters: {...uri.queryParameters, ...?queryParameters},
        queryParameters: queryParameters,
        fragment: uri.fragment);

    return http
        .get(uri, headers: _headers)
        .then(_handleResponse)
        .onError((error, stackTrace) => _handleError(error, stackTrace));
  }

  Future<Response?> delete(String url) {
    return http
        .delete(
          '${this.base}$url'.toUri()!,
          headers: _headers,
        )
        .then(_handleResponse)
        .onError((error, stackTrace) => _handleError(error, stackTrace));
  }

  Future<Response?> post(String url, {dynamic body}) {
    return http
        .post(
          '${this.base}$url'.toUri()!,
          headers: _headers,
          body: _encoder.convert(body),
        )
        .then(_handleResponse)
        .onError((error, stackTrace) => _handleError(error, stackTrace));
  }

  Future<Response?> put(String url, {dynamic body}) {
    return http
        .put(
          '${this.base}$url'.toUri()!,
          headers: _headers,
          body: _encoder.convert(body),
        )
        .then(_handleResponse)
        .onError((error, stackTrace) => _handleError(error, stackTrace));
  }

  Response? _handleError(Object? e, StackTrace? st) {
    if (global_scaffold_key == null) return null;
    SnackBar snackBar = SnackBar(
      content: Text("Error on request: " + e.toString()),
      action: SnackBarAction(
          label: "Clear",
          onPressed: () => global_scaffold_key!.currentState?.clearSnackBars()),
    );
    global_scaffold_key!.currentState?.showSnackBar(snackBar);
    return null;
  }

  Map<String, String> headersToMap(HttpHeaders headers) {
    Map<String, String> map = {};
    headers.forEach((name, values) {
      map[name] = values[0].toString();
    });
    return map;
  }

  Error? _handleResponseErrors(http.Response response) {
    if (response.statusCode < 200 || response.statusCode >= 400) {
      Map<String, dynamic> error;
      error = _decoder.convert(response.body);

      final SnackBar snackBar = SnackBar(
        content:
            Text("Error code " + response.statusCode.toString() + " received."),
        action: globalNavigatorKey.currentContext == null
            ? null
            : SnackBarAction(
                label: ("Details"),
                onPressed: () {
                  showDialog(
                      context: globalNavigatorKey.currentContext!,
                      builder: (BuildContext context) => AlertDialog(
                          title: Text("Error ${response.statusCode}"),
                          content: Column(
                            crossAxisAlignment: CrossAxisAlignment.start,
                            mainAxisSize: MainAxisSize.min,
                            children: [
                              Text(
                                "Message: ${error["message"]}",
                                textAlign: TextAlign.start,
                              ),
                              Text("Url: ${response.request!.url.toString()}"),
                            ],
                          )));
                },
              ),
      );
      if (global_scaffold_key != null && showSnackBar)
        global_scaffold_key!.currentState?.showSnackBar(snackBar);
      else
        print("error on request: ${error["message"]}");
    }
    return null;
  }

  Response? _handleResponse(http.Response response) {
    Error? error = _handleResponseErrors(response);
    return Response(
        _decoder.convert(response.body), response.statusCode, response.headers);
  }
}

class InvalidRequestApiException extends ApiException {
  final String message;

  InvalidRequestApiException(int errorCode, String path, this.message)
      : super(errorCode, path);

  @override
  String toString() {
    return this.message;
  }
}

class ApiException implements Exception {
  final int errorCode;
  final String path;

  ApiException(this.errorCode, this.path);

  @override
  String toString() {
    return "Can't fetch data from server. (Error-Code: $errorCode)";
  }
}