// islands/TenantSettings.tsx
import { useState } from "preact/hooks";
import { User } from "../db/interfaces.ts";

// Define the structure for the preference objects
interface NotificationPreferences {
  email_messages: boolean;
  email_reminders: boolean;
  email_payments: boolean;
}

interface PaymentPreferences {
  payment_reminders: boolean;
  // Note: default_auto_pay is typically lease-specific, this is for general preference
}

interface TenantSettingsProps {
  user: User;
}

function parsePreferences<T extends Record<string, boolean>>(
  raw: unknown,
  fallback: T,
): T {
  if (!raw) return fallback;
  if (typeof raw === "string") {
    try {
      const parsed = JSON.parse(raw) as Partial<T>;
      return { ...fallback, ...parsed };
    } catch {
      return fallback;
    }
  }
  if (typeof raw === "object") {
    return { ...fallback, ...(raw as Partial<T>) };
  }
  return fallback;
}

export default function TenantSettings({ user }: TenantSettingsProps) {
  const initialNotifPrefs: NotificationPreferences = parsePreferences(
    user.notification_preferences_json as unknown,
    {
      email_messages: true,
      email_reminders: true,
      email_payments: true,
    },
  );

  const initialPaymentPrefs: PaymentPreferences = parsePreferences(
    user.payment_preferences_json as unknown,
    {
      payment_reminders: true,
    },
  );

  const [notificationPrefs, setNotificationPrefs] = useState(initialNotifPrefs);
  const [paymentPrefs, setPaymentPrefs] = useState(initialPaymentPrefs);
  const [status, setStatus] = useState<"idle" | "saving" | "success" | "error">(
    "idle",
  );
  const [errorMessage, setErrorMessage] = useState<string | null>(null);

  const handleNotificationChange = (key: keyof NotificationPreferences) => {
    setNotificationPrefs((prev) => ({ ...prev, [key]: !prev[key] }));
  };

  const handlePaymentChange = (key: keyof PaymentPreferences) => {
    setPaymentPrefs((prev) => ({ ...prev, [key]: !prev[key] }));
  };

  const handleSubmit = async (e: Event) => {
    e.preventDefault();
    setStatus("saving");
    setErrorMessage(null);

    try {
      const response = await fetch("/api/user/preferences", {
        method: "POST",
        headers: {
          "Content-Type": "application/json",
        },
        body: JSON.stringify({
          notification_preferences: notificationPrefs,
          payment_preferences: paymentPrefs,
        }),
      });

      if (response.ok) {
        setStatus("success");
        setTimeout(() => setStatus("idle"), 3000);
      } else {
        const errorData = await response.json();
        setErrorMessage(errorData.error || "Failed to save preferences.");
        setStatus("error");
      }
    } catch (e) {
      console.error("Submission error:", e);
      setErrorMessage("An unexpected error occurred.");
      setStatus("error");
    }
  };

  const StatusMessage = () => {
    switch (status) {
      case "saving":
        return <div class="text-blue-600 text-sm">Saving...</div>;
      case "success":
        return (
          <div class="text-green-600 text-sm">
            Preferences saved successfully!
          </div>
        );
      case "error":
        return <div class="text-red-600 text-sm">Error: {errorMessage}</div>;
      default:
        return null;
    }
  };

  const PreferenceToggle = ({ label, checked, onChange }: {
    label: string;
    checked: boolean;
    onChange: () => void;
  }) => (
    <div class="flex items-center justify-between py-3 border-b border-gray-100 last:border-b-0">
      <span class="text-sm font-medium text-gray-700">{label}</span>
      <label class="relative inline-flex items-center cursor-pointer">
        <input
          type="checkbox"
          checked={checked}
          onChange={onChange}
          class="sr-only peer"
          disabled={status === "saving"}
        />
        <div class="w-11 h-6 bg-gray-200 peer-focus:outline-none peer-focus:ring-4 peer-focus:ring-blue-300 rounded-full peer peer-checked:after:translate-x-full peer-checked:after:border-white after:content-[''] after:absolute after:top-[2px] after:left-[2px] after:bg-white after:border-gray-300 after:border after:rounded-full after:h-5 after:w-5 after:transition-all peer-checked:bg-blue-600">
        </div>
      </label>
    </div>
  );

  return (
    <form onSubmit={handleSubmit} class="space-y-8">
      {/* Notification Preferences */}
      <div class="bg-white shadow sm:rounded-lg">
        <div class="px-4 py-5 sm:p-6">
          <h2 class="text-lg leading-6 font-medium text-gray-900">
            Notification Preferences
          </h2>
          <p class="mt-1 text-sm text-gray-500">
            Control how you receive alerts about your tenancy.
          </p>
          <div class="mt-6 space-y-4">
            <PreferenceToggle
              label="Email for New Messages"
              checked={notificationPrefs.email_messages}
              onChange={() => handleNotificationChange("email_messages")}
            />
            <PreferenceToggle
              label="Email for Reminders (Rent, Tasks)"
              checked={notificationPrefs.email_reminders}
              onChange={() => handleNotificationChange("email_reminders")}
            />
            <PreferenceToggle
              label="Email for Payment Confirmations"
              checked={notificationPrefs.email_payments}
              onChange={() => handleNotificationChange("email_payments")}
            />
          </div>
        </div>
      </div>

      {/* Payment Preferences */}
      <div class="bg-white shadow sm:rounded-lg">
        <div class="px-4 py-5 sm:p-6">
          <h2 class="text-lg leading-6 font-medium text-gray-900">
            Payment Preferences
          </h2>
          <p class="mt-1 text-sm text-gray-500">
            Manage settings related to your rent payments.
          </p>
          <div class="mt-6 space-y-4">
            <PreferenceToggle
              label="Receive Payment Due Reminders"
              checked={paymentPrefs.payment_reminders}
              onChange={() => handlePaymentChange("payment_reminders")}
            />
            <div class="mt-4">
              <a
                href="/tenant/payment-methods"
                class="text-blue-600 hover:text-blue-500 font-medium"
              >
                Manage Payment Methods →
              </a>
            </div>
            {/* Auto-pay setup is handled on the Payment Methods page, not here */}
          </div>
        </div>
      </div>

      {/* Save Button and Status */}
      <div class="flex justify-end items-center space-x-4">
        <StatusMessage />
        <button
          type="submit"
          disabled={status === "saving"}
          class="inline-flex justify-center py-2 px-4 border border-transparent shadow-sm text-sm font-medium rounded-md text-white bg-blue-600 hover:bg-blue-700 focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-blue-500 disabled:opacity-50"
        >
          {status === "saving" ? "Saving..." : "Save Changes"}
        </button>
      </div>
    </form>
  );
}