import React, { useEffect, useState } from "react";
import { Sheet } from "react-modal-sheet";
import { Link } from "react-router";
import { useTranslation } from "react-i18next";
import { Clock, RefreshCw } from "lucide-react";
import LineIcon from "./LineIcon";
import { StopSheetSkeleton } from "./StopSheetSkeleton";
import { ErrorDisplay } from "./ErrorDisplay";
import { StopAlert } from "./StopAlert";
import { type Estimate } from "../routes/estimates-$id";
import { REGIONS, type RegionId, getRegionConfig } from "../data/RegionConfig";
import { useApp } from "../AppContext";
import "./StopSheet.css";
import type { Stop } from "~/data/StopDataProvider";

interface StopSheetProps {
  isOpen: boolean;
  onClose: () => void;
  stop: Stop;
}

interface ErrorInfo {
  type: "network" | "server" | "unknown";
  status?: number;
  message?: string;
}

const loadStopData = async (
  region: RegionId,
  stopId: number,
): Promise<Estimate[]> => {
  const regionConfig = getRegionConfig(region);
  const resp = await fetch(`${regionConfig.estimatesEndpoint}?id=${stopId}`, {
    headers: {
      Accept: "application/json",
    },
  });

  if (!resp.ok) {
    throw new Error(`HTTP ${resp.status}: ${resp.statusText}`);
  }

  return await resp.json();
};

export const StopSheet: React.FC<StopSheetProps> = ({
  isOpen,
  onClose,
  stop,
}) => {
  const { t } = useTranslation();
  const { region } = useApp();
  const regionConfig = getRegionConfig(region);
  const [data, setData] = useState<Estimate[] | null>(null);
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState<ErrorInfo | null>(null);
  const [lastUpdated, setLastUpdated] = useState<Date | null>(null);

  const parseError = (error: any): ErrorInfo => {
    if (!navigator.onLine) {
      return { type: "network", message: "No internet connection" };
    }

    if (
      error.message?.includes("Failed to fetch") ||
      error.message?.includes("NetworkError")
    ) {
      return { type: "network" };
    }

    if (error.message?.includes("HTTP")) {
      const statusMatch = error.message.match(/HTTP (\d+):/);
      const status = statusMatch ? parseInt(statusMatch[1]) : undefined;
      return { type: "server", status };
    }

    return { type: "unknown", message: error.message };
  };

  const loadData = async () => {
    try {
      setLoading(true);
      setError(null);
      setData(null);

      const stopData = await loadStopData(region, stop.stopId);
      setData(stopData);
      setLastUpdated(new Date());
    } catch (err) {
      console.error("Failed to load stop data:", err);
      setError(parseError(err));
    } finally {
      setLoading(false);
    }
  };

  useEffect(() => {
    if (isOpen && stop.stopId) {
      loadData();
    }
  }, [isOpen, stop.stopId, region]);

  const formatTime = (minutes: number) => {
    if (minutes > 15) {
      const now = new Date();
      const arrival = new Date(now.getTime() + minutes * 60000);
      return Intl.DateTimeFormat(
        typeof navigator !== "undefined" ? navigator.language : "en",
        {
          hour: "2-digit",
          minute: "2-digit",
        },
      ).format(arrival);
    } else {
      return `${minutes} ${t("estimates.minutes", "min")}`;
    }
  };

  const formatDistance = (meters: number) => {
    if (meters > 1024) {
      return `${(meters / 1000).toFixed(1)} km`;
    } else {
      return `${meters} ${t("estimates.meters", "m")}`;
    }
  };

  // Show only the next 4 arrivals
  const limitedEstimates =
    data?.sort((a, b) => a.minutes - b.minutes).slice(0, 4) || [];

  return (
    <Sheet isOpen={isOpen} onClose={onClose} detent={"content-height" as any}>
      <Sheet.Container drag="y">
        <Sheet.Header />
        <Sheet.Content>
          <div className="stop-sheet-content">
            <div className="stop-sheet-header">
              <h2 className="stop-sheet-title">{stop.name.original}</h2>
              <span className="stop-sheet-id">({stop.stopId})</span>
            </div>

            <div
              className={`stop-sheet-lines-container ${stop.lines.length >= 10 ? "scrollable" : ""}`}
            >
              {stop.lines.map((line) => (
                <div key={line} className="stop-sheet-line-icon">
                  <LineIcon line={line} region={region} rounded />
                </div>
              ))}
            </div>

            <StopAlert stop={stop} compact />

            {loading ? (
              <StopSheetSkeleton />
            ) : error ? (
              <ErrorDisplay
                error={error}
                onRetry={loadData}
                title={t(
                  "errors.estimates_title",
                  "Error al cargar estimaciones",
                )}
                className="compact"
              />
            ) : data ? (
              <>
                <div className="stop-sheet-estimates">
                  <h3 className="stop-sheet-subtitle">
                    {t("estimates.next_arrivals", "Next arrivals")}
                  </h3>

                  {limitedEstimates.length === 0 ? (
                    <div className="stop-sheet-no-estimates">
                      {t("estimates.none", "No hay estimaciones disponibles")}
                    </div>
                  ) : (
                    <div className="stop-sheet-estimates-list">
                      {limitedEstimates.map((estimate, idx) => (
                        <div key={idx} className="stop-sheet-estimate-item">
                          <div className="stop-sheet-estimate-line">
                            <LineIcon line={estimate.line} region={region} />
                          </div>
                          <div className="stop-sheet-estimate-details">
                            <div className="stop-sheet-estimate-route">
                              {estimate.route}
                            </div>
                          </div>
                          <div className="stop-sheet-estimate-arrival">
                            <div
                              className={`stop-sheet-estimate-time ${estimate.minutes <= 15 ? "is-minutes" : ""}`}
                            >
                              <Clock />
                              {formatTime(estimate.minutes)}
                            </div>
                            {REGIONS[region].showMeters &&
                              estimate.meters >= 0 && (
                                <div className="stop-sheet-estimate-distance">
                                  {formatDistance(estimate.meters)}
                                </div>
                              )}
                          </div>
                        </div>
                      ))}
                    </div>
                  )}
                </div>

                <div className="stop-sheet-footer">
                  {lastUpdated && (
                    <div className="stop-sheet-timestamp">
                      {t("estimates.last_updated", "Actualizado a las")}{" "}
                      {lastUpdated.toLocaleTimeString(undefined, {
                        hour: "2-digit",
                        minute: "2-digit",
                        second: "2-digit",
                      })}
                    </div>
                  )}

                  <div className="stop-sheet-actions">
                    <button
                      className="stop-sheet-reload"
                      onClick={loadData}
                      disabled={loading}
                      title={t("estimates.reload", "Recargar estimaciones")}
                    >
                      <RefreshCw
                        className={`reload-icon ${loading ? "spinning" : ""}`}
                      />
                      {t("estimates.reload", "Recargar")}
                    </button>

                    <Link
                      to={`/estimates/${stop.stopId}`}
                      className="stop-sheet-view-all"
                      onClick={onClose}
                    >
                      {t(
                        "map.view_all_estimates",
                        "Ver todas las estimaciones",
                      )}
                    </Link>
                  </div>
                </div>
              </>
            ) : null}
          </div>
        </Sheet.Content>
      </Sheet.Container>
      <Sheet.Backdrop onTap={onClose} />
    </Sheet>
  );
};