import "dart:convert";
import "package:http/http.dart" as http;

import "../models/restaurant.dart";
import "../models/service_point.dart";

class Api {
  static String get baseUrl {
    const v = String.fromEnvironment("API_BASE_URL");
    if (v.isEmpty) {
      throw StateError(
        "API_BASE_URL is not set. Example (Android emulator): "
        "--dart-define=API_BASE_URL=http://10.0.2.2:8888/biz.payfrit.com/api",
      );
    }
    return v;
  }

  static Uri _u(String path) {
    final normalizedBase =
        baseUrl.endsWith("/") ? baseUrl.substring(0, baseUrl.length - 1) : baseUrl;
    final normalizedPath = path.startsWith("/") ? path : "/$path";
    return Uri.parse("$normalizedBase$normalizedPath");
  }

  static Future<_ApiResponse> _getJson(String path) async {
    final url = _u(path);
    final resp = await http.get(url);

    final body = resp.body;
    Map<String, dynamic>? json;
    try {
      final decoded = jsonDecode(body);
      if (decoded is Map<String, dynamic>) {
        json = decoded;
      }
    } catch (_) {
      // leave json null
    }

    // ignore: avoid_print
    print("API GET  => $url");
    // ignore: avoid_print
    print("STATUS   => ${resp.statusCode}");
    // ignore: avoid_print
    print("BODY     => ${body.length > 1200 ? body.substring(0, 1200) + '…' : body}");

    return _ApiResponse(
      statusCode: resp.statusCode,
      rawBody: body,
      json: json,
    );
  }

  static Future<_ApiResponse> _postJson(String path, Map<String, dynamic> payload) async {
    final url = _u(path);
    final resp = await http.post(
      url,
      headers: {"Content-Type": "application/json"},
      body: jsonEncode(payload),
    );

    final body = resp.body;
    Map<String, dynamic>? json;
    try {
      final decoded = jsonDecode(body);
      if (decoded is Map<String, dynamic>) {
        json = decoded;
      }
    } catch (_) {
      // leave json null
    }

    // ignore: avoid_print
    print("API POST => $url");
    // ignore: avoid_print
    print("BODY IN  => ${jsonEncode(payload)}");
    // ignore: avoid_print
    print("STATUS   => ${resp.statusCode}");
    // ignore: avoid_print
    print("BODY OUT => ${body.length > 1200 ? body.substring(0, 1200) + '…' : body}");

    return _ApiResponse(
      statusCode: resp.statusCode,
      rawBody: body,
      json: json,
    );
  }

  static void _throwIfApiError(Map<String, dynamic> data, String context) {
    if (data.containsKey("OK") && data["OK"] is bool && (data["OK"] as bool) == false) {
      final err = data["ERROR"];
      final detail = data["DETAIL"];
      final msg = data["MESSAGE"];
      throw StateError(
        "$context API returned OK=false"
        "${err != null ? "\nERROR: $err" : ""}"
        "${msg != null ? "\nMESSAGE: $msg" : ""}"
        "${detail != null ? "\nDETAIL: $detail" : ""}",
      );
    }
  }

  static Future<_ApiResponse> listRestaurantsRaw() async {
    return _getJson("/businesses/list.cfm");
  }

  static Future<List<Restaurant>> listRestaurants() async {
    final r = await listRestaurantsRaw();
    if (r.statusCode != 200) {
      throw StateError("Restaurants request failed: ${r.statusCode}\n${r.rawBody}");
    }

    final data = r.json;
    if (data == null) {
      throw StateError("Restaurants response was not JSON.\n${r.rawBody}");
    }

    _throwIfApiError(data, "Restaurants");

    final rows = data["Businesses"];
    if (rows is! List) {
      throw StateError(
        "Restaurants JSON missing Businesses array.\nKeys present: ${data.keys.toList()}\nRaw: ${r.rawBody}",
      );
    }

    return rows
        .whereType<Map<String, dynamic>>()
        .map((e) => Restaurant.fromJson(e))
        .toList();
  }

  static Future<_ApiResponse> listServicePointsRaw({required int businessId}) async {
    return _postJson("/servicepoints/list.cfm", {"BusinessID": businessId});
  }

  static Future<List<ServicePoint>> listServicePoints({required int businessId}) async {
    final r = await listServicePointsRaw(businessId: businessId);
    if (r.statusCode != 200) {
      throw StateError("ServicePoints request failed: ${r.statusCode}\n${r.rawBody}");
    }

    final data = r.json;
    if (data == null) {
      throw StateError("ServicePoints response was not JSON.\n${r.rawBody}");
    }

    _throwIfApiError(data, "ServicePoints");

    // STRICT: hump case
    final rows = data["ServicePoints"];
    if (rows is! List) {
      throw StateError(
        "ServicePoints JSON missing ServicePoints array.\nKeys present: ${data.keys.toList()}\nRaw: ${r.rawBody}",
      );
    }

    return rows
        .whereType<Map<String, dynamic>>()
        .map((e) => ServicePoint.fromJson(e))
        .toList();
  }
}

class _ApiResponse {
  final int statusCode;
  final String rawBody;
  final Map<String, dynamic>? json;

  const _ApiResponse({
    required this.statusCode,
    required this.rawBody,
    required this.json,
  });
}