"use client";

import { useRef, useState } from "react";
import { useFocusTrap } from "~/hooks/useFocusTrap.js";
import { trpc } from "~/lib/trpc/client.js";

const TARGET_TYPES = [
  { value: "all", label: "All Users" },
  { value: "role", label: "By Role" },
  { value: "project", label: "By Project" },
  { value: "orgUnit", label: "By Org Unit" },
] as const;

const ROLES = ["ADMIN", "MANAGER", "CONTROLLER", "USER", "VIEWER"] as const;

const PRIORITY_OPTIONS = [
  { value: "LOW", label: "Low" },
  { value: "NORMAL", label: "Normal" },
  { value: "HIGH", label: "High" },
  { value: "URGENT", label: "Urgent" },
] as const;

const CHANNEL_OPTIONS = [
  { value: "in_app", label: "In-App" },
  { value: "email", label: "Email" },
  { value: "both", label: "Both" },
] as const;

interface BroadcastModalProps {
  onClose: () => void;
  onSuccess: () => void;
}

export function BroadcastModal({ onClose, onSuccess }: BroadcastModalProps) {
  const [title, setTitle] = useState("");
  const [body, setBody] = useState("");
  const [targetType, setTargetType] = useState<string>("all");
  const [targetValue, setTargetValue] = useState("");
  const [priority, setPriority] = useState("NORMAL");
  const [channel, setChannel] = useState("in_app");
  const [link, setLink] = useState("");
  const [serverError, setServerError] = useState<string | null>(null);
  const [result, setResult] = useState<{ recipientCount: number } | null>(null);

  const panelRef = useRef<HTMLDivElement>(null);
  useFocusTrap(panelRef, true);

  const utils = trpc.useUtils();

  const createMutation = trpc.notification.createBroadcast.useMutation({
    onSuccess: async (data) => {
      await utils.notification.listBroadcasts.invalidate();
      const count = (data as { recipientCount?: number }).recipientCount ?? 0;
      setResult({ recipientCount: count });
    },
    onError: (err) => setServerError(err.message),
  });

  const isPending = createMutation.isPending;

  function handleSubmit(e: React.FormEvent) {
    e.preventDefault();
    setServerError(null);

    if (!title.trim()) {
      setServerError("Title is required.");
      return;
    }

    createMutation.mutate({
      title: title.trim(),
      ...(body.trim() ? { body: body.trim() } : {}),
      targetType: targetType as "all" | "role" | "project" | "orgUnit" | "user",
      ...(targetType !== "all" && targetValue.trim() ? { targetValue: targetValue.trim() } : {}),
      priority: priority as "LOW" | "NORMAL" | "HIGH" | "URGENT",
      channel: channel as "in_app" | "email" | "both",
      ...(link.trim() ? { link: link.trim() } : {}),
    });
  }

  const inputClass =
    "w-full px-3 py-2 border border-gray-300 dark:border-gray-600 rounded-lg focus:outline-none focus:ring-2 focus:ring-brand-500 text-sm dark:bg-gray-900 dark:text-gray-100";
  const labelClass = "block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1";

  // After successful send, show result
  if (result) {
    return (
      <div
        className="fixed inset-0 bg-black/50 z-50 flex items-start justify-center overflow-y-auto py-8"
        onClick={(e) => {
          if (e.target === e.currentTarget) { onSuccess(); onClose(); }
        }}
      >
        <div
          ref={panelRef}
          className="bg-white dark:bg-gray-800 rounded-xl shadow-2xl w-full max-w-lg mx-4"
          onKeyDown={(e) => { if (e.key === "Escape") { onSuccess(); onClose(); } }}
        >
          <div className="px-6 py-8 text-center">
            <div className="mx-auto mb-4 flex h-12 w-12 items-center justify-center rounded-full bg-green-100 dark:bg-green-900/30">
              <svg className="h-6 w-6 text-green-600 dark:text-green-400" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M5 13l4 4L19 7" />
              </svg>
            </div>
            <h3 className="text-lg font-semibold text-gray-900 dark:text-gray-100">Broadcast Sent</h3>
            <p className="mt-2 text-sm text-gray-500 dark:text-gray-400">
              Sent to {result.recipientCount} recipient{result.recipientCount !== 1 ? "s" : ""}
            </p>
            <button
              type="button"
              onClick={() => { onSuccess(); onClose(); }}
              className="mt-6 px-4 py-2 bg-brand-600 text-white rounded-lg hover:bg-brand-700 text-sm font-medium"
            >
              Close
            </button>
          </div>
        </div>
      </div>
    );
  }

  return (
    <div
      className="fixed inset-0 bg-black/50 z-50 flex items-start justify-center overflow-y-auto py-8"
      onClick={(e) => {
        if (e.target === e.currentTarget) onClose();
      }}
    >
      <div
        ref={panelRef}
        className="bg-white dark:bg-gray-800 rounded-xl shadow-2xl w-full max-w-lg mx-4"
        onKeyDown={(e) => { if (e.key === "Escape") onClose(); }}
      >
        {/* Header */}
        <div className="flex items-center justify-between px-6 py-4 border-b border-gray-200 dark:border-gray-700">
          <h2 className="text-lg font-semibold text-gray-900 dark:text-gray-100">Send Broadcast</h2>
          <button
            type="button"
            onClick={onClose}
            className="text-gray-400 hover:text-gray-600 dark:hover:text-gray-300 transition-colors text-xl leading-none"
            aria-label="Close"
          >
            &times;
          </button>
        </div>

        <form onSubmit={handleSubmit} className="px-6 py-5 space-y-4">
          {/* Title */}
          <div>
            <label htmlFor="bc-title" className={labelClass}>
              Title <span className="text-red-500">*</span>
            </label>
            <input
              id="bc-title"
              type="text"
              value={title}
              onChange={(e) => setTitle(e.target.value)}
              maxLength={200}
              className={inputClass}
              required
              placeholder="Broadcast title..."
            />
          </div>

          {/* Body */}
          <div>
            <label htmlFor="bc-body" className={labelClass}>
              Message (optional)
            </label>
            <textarea
              id="bc-body"
              value={body}
              onChange={(e) => setBody(e.target.value)}
              rows={3}
              maxLength={2000}
              className={`${inputClass} resize-none`}
              placeholder="Message body..."
            />
          </div>

          {/* Target type */}
          <div>
            <label htmlFor="bc-target" className={labelClass}>
              Target Audience
            </label>
            <select
              id="bc-target"
              value={targetType}
              onChange={(e) => { setTargetType(e.target.value); setTargetValue(""); }}
              className={inputClass}
            >
              {TARGET_TYPES.map((t) => (
                <option key={t.value} value={t.value}>{t.label}</option>
              ))}
            </select>
          </div>

          {/* Target value selector */}
          {targetType === "role" && (
            <div>
              <label htmlFor="bc-role" className={labelClass}>
                Role
              </label>
              <select
                id="bc-role"
                value={targetValue}
                onChange={(e) => setTargetValue(e.target.value)}
                className={inputClass}
              >
                <option value="">Select a role...</option>
                {ROLES.map((r) => (
                  <option key={r} value={r}>{r}</option>
                ))}
              </select>
            </div>
          )}

          {targetType === "project" && (
            <div>
              <label htmlFor="bc-project" className={labelClass}>
                Project ID
              </label>
              <input
                id="bc-project"
                type="text"
                value={targetValue}
                onChange={(e) => setTargetValue(e.target.value)}
                className={inputClass}
                placeholder="Project ID..."
              />
            </div>
          )}

          {targetType === "orgUnit" && (
            <div>
              <label htmlFor="bc-orgunit" className={labelClass}>
                Org Unit ID
              </label>
              <input
                id="bc-orgunit"
                type="text"
                value={targetValue}
                onChange={(e) => setTargetValue(e.target.value)}
                className={inputClass}
                placeholder="Org Unit ID..."
              />
            </div>
          )}

          {/* Priority + Channel */}
          <div className="grid grid-cols-2 gap-4">
            <div>
              <label htmlFor="bc-priority" className={labelClass}>
                Priority
              </label>
              <select
                id="bc-priority"
                value={priority}
                onChange={(e) => setPriority(e.target.value)}
                className={inputClass}
              >
                {PRIORITY_OPTIONS.map((p) => (
                  <option key={p.value} value={p.value}>{p.label}</option>
                ))}
              </select>
            </div>
            <div>
              <label htmlFor="bc-channel" className={labelClass}>
                Channel
              </label>
              <select
                id="bc-channel"
                value={channel}
                onChange={(e) => setChannel(e.target.value)}
                className={inputClass}
              >
                {CHANNEL_OPTIONS.map((c) => (
                  <option key={c.value} value={c.value}>{c.label}</option>
                ))}
              </select>
            </div>
          </div>

          {/* Link */}
          <div>
            <label htmlFor="bc-link" className={labelClass}>
              Link (optional)
            </label>
            <input
              id="bc-link"
              type="text"
              value={link}
              onChange={(e) => setLink(e.target.value)}
              className={inputClass}
              placeholder="/some/page or https://..."
            />
          </div>

          {/* Server error */}
          {serverError && (
            <div className="rounded-lg bg-red-50 border border-red-200 px-4 py-3 text-sm text-red-700 dark:bg-red-900/20 dark:border-red-800 dark:text-red-300">
              {serverError}
            </div>
          )}

          {/* Footer */}
          <div className="flex items-center justify-end gap-3 pt-2">
            <button
              type="button"
              onClick={onClose}
              disabled={isPending}
              className="px-4 py-2 text-sm font-medium text-gray-700 dark:text-gray-300 hover:text-gray-900 dark:hover:text-gray-100 disabled:opacity-50"
            >
              Cancel
            </button>
            <button
              type="submit"
              disabled={isPending}
              className="px-4 py-2 bg-brand-600 text-white rounded-lg hover:bg-brand-700 text-sm font-medium disabled:opacity-50"
            >
              {isPending ? "Sending..." : "Send Broadcast"}
            </button>
          </div>
        </form>
      </div>
    </div>
  );
}
