import React, { useState, useEffect, useMemo } from "react";
import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
import { __ } from "../lib/i18n";
import { useToast } from "../components/ui/toast";
import {
  Card,
  CardContent,
  CardHeader,
  CardTitle,
} from "../components/ui/card";
import { Button } from "../components/ui/button";
import { Input } from "../components/ui/input";
import { Badge } from "../components/ui/badge";
import {
  Mail,
  ArrowLeft,
  Save,
  Eye,
  Send,
  Loader2,
  Code,
  Copy,
  Check,
  Info,
  Zap,
  ChevronDown,
  Sparkles,
} from "lucide-react";
import { AiEmailTemplateModal } from "../components/ai/AiEmailTemplateModal";
import { isAiEligible, isAiModuleEnabled } from "../lib/ai-availability";
import { Switch } from "../components/ui/switch";
import {
  getCatalogEntryByTemplateKey,
  getCoreTemplateDefinition,
  isCoreTemplateSlug,
} from "../lib/email-templates-catalog";
import {
  isEmailAutomationModuleEnabled,
  isModuleActive,
  isProPluginActive,
} from "../lib/plugin-utils";
import {
  fetchSettings,
  previewCoreEmailTemplate,
  saveSettings,
} from "../api/settings-api";
import { EmailPreviewModal } from "../components/email/EmailPreviewModal";
import {
  createEmailTemplate,
  fetchEmailTemplate,
  fetchEmailTemplateVariables,
  previewEmailTemplate,
  sendEmailTemplateTest,
  updateEmailTemplate,
} from "../api/email-automation-api";

interface PreviewData {
  subject: string;
  body: string;
}

const EmailTemplateForm: React.FC = () => {
  const { id, isCreateMode, coreTemplateSlug, coreReadOnlyParam } =
    useMemo(() => {
      const params = new URLSearchParams(window.location.search);
      const templateId = params.get("id");
      const action = params.get("action");
      const core = params.get("core_template") || "";
      return {
        id: templateId,
        isCreateMode: action === "create",
        coreTemplateSlug: core,
        coreReadOnlyParam: params.get("readonly") === "1",
      };
    }, []);

  const isCoreSettingsEdit = isCoreTemplateSlug(coreTemplateSlug);
  const coreDef = isCoreSettingsEdit
    ? getCoreTemplateDefinition(coreTemplateSlug)
    : undefined;

  const catalogEntryForCore = useMemo(
    () =>
      coreTemplateSlug
        ? getCatalogEntryByTemplateKey(coreTemplateSlug)
        : undefined,
    [coreTemplateSlug],
  );

  /** URL ?readonly=1 — no edits at all from this screen */
  const isCoreStrictViewOnly = isCoreSettingsEdit && Boolean(coreReadOnlyParam);

  /** Module required but inactive: subject/body/save locked; on/off can still be changed (site setting). */
  const isCoreModuleBodyLocked = useMemo(() => {
    if (!isCoreSettingsEdit || isCoreStrictViewOnly) {
      return false;
    }
    const req = catalogEntryForCore?.requiresModule;
    if (!req) {
      return false;
    }
    return !isProPluginActive() || !isModuleActive(req);
  }, [isCoreSettingsEdit, isCoreStrictViewOnly, catalogEntryForCore]);

  /** Subject/body (and merge-tag insert) read-only; strict URL also locks status. */
  const isCoreBodyReadOnly = isCoreStrictViewOnly || isCoreModuleBodyLocked;

  const isCoreViewMode = isCoreStrictViewOnly || isCoreModuleBodyLocked;

  const goBack = () => {
    window.location.href = `admin.php?page=yatra&subpage=email-automation&tab=templates`;
  };
  const queryClient = useQueryClient();
  const { showToast } = useToast();

  const [formData, setFormData] = useState({
    name: "",
    description: "",
    from_name: "",
    from_email: "",
    to_email: "",
    reply_to: "",
    subject: "",
    body: "",
    event_key: "",
    is_active: true,
  });
  const [showPreview, setShowPreview] = useState(false);
  const [previewData, setPreviewData] = useState<PreviewData | null>(null);
  const [testEmail, setTestEmail] = useState("");
  const [copiedVar, setCopiedVar] = useState<string | null>(null);
  const [showEventDropdown, setShowEventDropdown] = useState(false);
  const [showAiModal, setShowAiModal] = useState(false);

  useEffect(() => {
    if (isCreateMode && !isEmailAutomationModuleEnabled()) {
      window.location.href =
        "admin.php?page=yatra&subpage=email-automation&tab=templates";
    }
  }, [isCreateMode]);

  useEffect(() => {
    const params = new URLSearchParams(window.location.search);
    if (params.get("action") !== "edit") return;
    const ct = params.get("core_template");
    if (ct && !isCoreTemplateSlug(ct)) {
      window.location.href =
        "admin.php?page=yatra&subpage=email-automation&tab=templates";
    }
  }, []);

  const { data: settings, isLoading: settingsLoading } = useQuery({
    queryKey: ["settings"],
    queryFn: () => fetchSettings(),
    enabled: isCoreSettingsEdit,
  });

  const { data: templateData, isLoading } = useQuery({
    queryKey: ["email-template", id],
    queryFn: () => fetchEmailTemplate(id as string),
    enabled: Boolean(id) && !isCoreSettingsEdit,
  });

  // Event-scoped variables: the sidebar re-fetches whenever the
  // operator switches the trigger event so the "Available
  // Variables" panel reflects only tags that will actually
  // resolve at send-time for the chosen event. Empty event_key
  // returns the full union (for the create-template starter
  // state before they've picked an event).
  const { data: variablesData } = useQuery({
    queryKey: ["email-variables", formData.event_key || ""],
    queryFn: () => fetchEmailTemplateVariables(formData.event_key || ""),
    enabled: !isCoreSettingsEdit && isEmailAutomationModuleEnabled(),
  });

  // Get events from window.yatraAdmin (passed from PHP)
  const events = (window as any).yatraAdmin?.emailEvents || [];

  useEffect(() => {
    if (!templateData || typeof templateData !== "object") return;
    const t = templateData as Record<string, unknown>;
    setFormData({
      name: String(t.name ?? ""),
      description: String(t.description ?? ""),
      from_name: String(t.from_name ?? ""),
      from_email: String(t.from_email ?? ""),
      to_email: String(t.to_email ?? ""),
      reply_to: String(t.reply_to ?? ""),
      subject: String(t.subject ?? ""),
      body: String(t.body ?? ""),
      event_key: String(t.event_key ?? ""),
      is_active: Boolean(t.is_active ?? true),
    });
  }, [templateData]);

  useEffect(() => {
    if (!isCoreSettingsEdit || !settings || !coreDef) return;
    const flag = coreDef.settingsFlag;
    const subj = coreDef.settingsSubject;
    const bodyKey = coreDef.settingsBody;
    if (!flag || !subj || !bodyKey) return;
    const s = settings as Record<string, unknown>;
    setFormData({
      name: coreDef.name,
      description: coreDef.description,
      from_name: "",
      from_email: "",
      to_email: coreDef.to_email || "",
      reply_to: "",
      subject: String(s[subj] ?? ""),
      body: String(s[bodyKey] ?? ""),
      event_key: coreDef.event_key,
      is_active: Boolean(s[flag]),
    });
  }, [isCoreSettingsEdit, settings, coreDef]);

  const saveMutation = useMutation({
    mutationFn: async (data: typeof formData) => {
      if (isCreateMode) {
        const response = await createEmailTemplate(data);
        const r = response as {
          success?: boolean;
          message?: string;
          data?: { id?: string | number };
        };
        if (r && r.success === false) {
          throw new Error(r.message || __("Failed to create template"));
        }
        return response;
      }
      return await updateEmailTemplate(id as string, data);
    },
    onSuccess: (response) => {
      queryClient.invalidateQueries({ queryKey: ["email-templates"] });
      if (isCreateMode) {
        showToast(__("Template created successfully"), "success");
        // Redirect to edit page after creation - response.data contains the template
        const newId = (response as { data?: { id?: string | number } })?.data
          ?.id;
        if (newId) {
          window.location.href = `admin.php?page=yatra&subpage=email-automation&tab=template&action=edit&id=${newId}`;
        } else {
          // Fallback to list page
          window.location.href =
            "admin.php?page=yatra&subpage=email-automation&tab=templates";
        }
      } else {
        queryClient.invalidateQueries({ queryKey: ["email-template", id] });
        showToast(__("Template saved successfully"), "success");
      }
    },
    onError: (error: any) => {
      const message =
        error?.message ||
        (isCreateMode
          ? __("Failed to create template")
          : __("Failed to save template"));
      showToast(message, "error");
    },
  });

  const saveCoreMutation = useMutation({
    mutationFn: async () => {
      if (isCoreStrictViewOnly) {
        throw new Error(__("This template is view-only.", "yatra"));
      }
      if (
        !coreDef?.settingsFlag ||
        !coreDef.settingsSubject ||
        !coreDef.settingsBody
      ) {
        throw new Error(__("Invalid template", "yatra"));
      }
      if (!settings) {
        throw new Error(__("Settings not loaded", "yatra"));
      }
      const base = { ...(settings as Record<string, unknown>) };
      if (isCoreModuleBodyLocked) {
        base[coreDef.settingsFlag] = formData.is_active;
        await saveSettings(base);
        return base;
      }
      base[coreDef.settingsSubject] = formData.subject;
      base[coreDef.settingsBody] = formData.body;
      base[coreDef.settingsFlag] = formData.is_active;
      await saveSettings(base);
      return base;
    },
    onSuccess: (saved) => {
      queryClient.setQueryData(["settings"], saved);
      showToast(__("Template saved", "yatra"), "success");
    },
    onError: (error: unknown) => {
      const message =
        error instanceof Error ? error.message : __("Failed to save", "yatra");
      showToast(message, "error");
    },
  });

  const previewMutation = useMutation({
    mutationFn: async () => {
      return previewEmailTemplate(id as string);
    },
    onSuccess: (data) => {
      setPreviewData(data);
      setShowPreview(true);
    },
    onError: () => {
      showToast(__("Failed to load preview"), "error");
    },
  });

  const corePreviewMutation = useMutation({
    mutationFn: async () => {
      if (!coreTemplateSlug) {
        throw new Error(__("Invalid template", "yatra"));
      }
      return previewCoreEmailTemplate({
        template_key: coreTemplateSlug,
        subject: formData.subject,
        body: formData.body,
      });
    },
    onSuccess: (data) => {
      setPreviewData(data);
      setShowPreview(true);
    },
    onError: (error: unknown) => {
      const message =
        error instanceof Error ? error.message : __("Preview failed", "yatra");
      showToast(message, "error");
    },
  });

  const testMutation = useMutation({
    mutationFn: async (email: string) => {
      return sendEmailTemplateTest(id as string, email);
    },
    onSuccess: () => {
      showToast(__("Test email sent successfully"), "success");
      setTestEmail("");
    },
    onError: () => {
      showToast(__("Failed to send test email"), "error");
    },
  });

  const handleSubmit = (e?: React.FormEvent | React.MouseEvent) => {
    if (e) e.preventDefault();

    if (isCoreSettingsEdit) {
      if (isCoreStrictViewOnly) {
        return;
      }
      saveCoreMutation.mutate();
      return;
    }

    if (!formData.name.trim()) {
      showToast(__("Template name is required"), "error");
      return;
    }
    if (!formData.subject.trim()) {
      showToast(__("Subject line is required"), "error");
      return;
    }

    saveMutation.mutate(formData);
  };

  const copyVariable = (variable: string) => {
    navigator.clipboard.writeText(`{{${variable}}}`);
    setCopiedVar(variable);
    setTimeout(() => setCopiedVar(null), 2000);
  };

  const insertVariable = (variable: string) => {
    if (isCoreBodyReadOnly) {
      return;
    }
    const textarea = document.getElementById(
      "email-body",
    ) as HTMLTextAreaElement;
    if (textarea) {
      const start = textarea.selectionStart;
      const end = textarea.selectionEnd;
      const text = formData.body;
      const newText =
        text.substring(0, start) + `{{${variable}}}` + text.substring(end);
      setFormData({ ...formData, body: newText });
    }
  };

  const showEditSkeleton =
    !isCreateMode && (isCoreSettingsEdit ? settingsLoading : isLoading);

  if (showEditSkeleton) {
    return (
      <div className="space-y-6">
        {/* Header Skeleton */}
        <div className="flex items-center justify-between animate-pulse">
          <div className="flex items-center gap-4">
            <div className="h-10 w-20 bg-gray-200 dark:bg-gray-700 rounded"></div>
            <div>
              <div className="h-8 w-56 bg-gray-200 dark:bg-gray-700 rounded mb-2"></div>
              <div className="h-4 w-40 bg-gray-200 dark:bg-gray-700 rounded"></div>
            </div>
          </div>
          <div className="flex items-center gap-3">
            <div className="h-10 w-24 bg-gray-200 dark:bg-gray-700 rounded"></div>
            <div className="h-10 w-32 bg-gray-200 dark:bg-gray-700 rounded"></div>
          </div>
        </div>

        <div className="grid grid-cols-1 lg:grid-cols-3 gap-6">
          {/* Main Form Skeleton */}
          <div className="lg:col-span-2 space-y-6">
            {/* Template Details Card */}
            <Card>
              <CardHeader>
                <div className="flex items-center justify-between">
                  <div className="h-6 w-36 bg-gray-200 dark:bg-gray-700 rounded"></div>
                  <div className="h-6 w-20 bg-gray-200 dark:bg-gray-700 rounded"></div>
                </div>
              </CardHeader>
              <CardContent className="space-y-4">
                <div className="space-y-2">
                  <div className="h-4 w-28 bg-gray-200 dark:bg-gray-700 rounded"></div>
                  <div className="h-10 w-full bg-gray-200 dark:bg-gray-700 rounded"></div>
                </div>
                <div className="space-y-2">
                  <div className="h-4 w-24 bg-gray-200 dark:bg-gray-700 rounded"></div>
                  <div className="h-10 w-full bg-gray-200 dark:bg-gray-700 rounded"></div>
                </div>
                <div className="space-y-2">
                  <div className="h-4 w-20 bg-gray-200 dark:bg-gray-700 rounded"></div>
                  <div className="h-10 w-full bg-gray-200 dark:bg-gray-700 rounded"></div>
                </div>
                <div className="space-y-2">
                  <div className="h-4 w-32 bg-gray-200 dark:bg-gray-700 rounded"></div>
                  <div className="h-64 w-full bg-gray-200 dark:bg-gray-700 rounded"></div>
                </div>
              </CardContent>
            </Card>

            {/* Test Email Card */}
            <Card>
              <CardHeader>
                <div className="h-6 w-32 bg-gray-200 dark:bg-gray-700 rounded"></div>
              </CardHeader>
              <CardContent>
                <div className="flex gap-3">
                  <div className="h-10 flex-1 bg-gray-200 dark:bg-gray-700 rounded"></div>
                  <div className="h-10 w-10 bg-gray-200 dark:bg-gray-700 rounded"></div>
                </div>
              </CardContent>
            </Card>
          </div>

          {/* Sidebar Skeleton */}
          <div className="space-y-6">
            {/* Variables Card */}
            <Card>
              <CardHeader>
                <div className="h-6 w-36 bg-gray-200 dark:bg-gray-700 rounded"></div>
              </CardHeader>
              <CardContent className="space-y-4">
                <div className="h-4 w-full bg-gray-200 dark:bg-gray-700 rounded"></div>
                {[1, 2, 3].map((group) => (
                  <div key={group} className="space-y-2">
                    <div className="h-3 w-20 bg-gray-200 dark:bg-gray-700 rounded"></div>
                    {[1, 2, 3].map((item) => (
                      <div
                        key={item}
                        className="h-12 w-full bg-gray-200 dark:bg-gray-700 rounded"
                      ></div>
                    ))}
                  </div>
                ))}
              </CardContent>
            </Card>

            {/* Template Info Card */}
            <Card>
              <CardHeader>
                <div className="h-6 w-28 bg-gray-200 dark:bg-gray-700 rounded"></div>
              </CardHeader>
              <CardContent className="space-y-3">
                {[1, 2, 3].map((i) => (
                  <div key={i} className="flex justify-between">
                    <div className="h-4 w-16 bg-gray-200 dark:bg-gray-700 rounded"></div>
                    <div className="h-4 w-24 bg-gray-200 dark:bg-gray-700 rounded"></div>
                  </div>
                ))}
              </CardContent>
            </Card>
          </div>
        </div>
      </div>
    );
  }

  return (
    <div className="space-y-6">
      {/* Header */}
      <div className="flex items-center justify-between">
        <div className="flex items-center gap-4">
          <Button variant="ghost" onClick={() => goBack()}>
            <ArrowLeft className="w-4 h-4 mr-2" />
            {__("Back")}
          </Button>
          <div>
            <h1 className="text-2xl font-bold text-gray-900 dark:text-white flex items-center gap-2">
              <Mail className="w-6 h-6 text-blue-500" />
              {isCreateMode
                ? __("Create Email Template")
                : isCoreViewMode
                  ? __("View email template", "yatra")
                  : __("Edit Email Template")}
            </h1>
            <p className="text-gray-500 dark:text-gray-400 mt-1">
              {isCreateMode
                ? __("Create a new custom email template")
                : isCoreSettingsEdit
                  ? isCoreViewMode
                    ? __(
                        "This template uses site settings. Enable Yatra Pro and the required module to edit subject and HTML body.",
                        "yatra",
                      )
                    : __(
                        "Core customer email (saved with site settings). From address is set under Email → Delivery.",
                        "yatra",
                      )
                  : String(templateData?.name ?? "")}
            </p>
          </div>
        </div>
        <div className="flex items-center gap-3">
          {!isCreateMode && (
            <Button
              variant="outline"
              onClick={() =>
                isCoreSettingsEdit
                  ? corePreviewMutation.mutate()
                  : previewMutation.mutate()
              }
              disabled={
                previewMutation.isPending || corePreviewMutation.isPending
              }
            >
              {previewMutation.isPending || corePreviewMutation.isPending ? (
                <Loader2 className="w-4 h-4 mr-2 animate-spin" />
              ) : (
                <Eye className="w-4 h-4 mr-2" />
              )}
              {__("Preview")}
            </Button>
          )}
          <Button
            onClick={handleSubmit}
            disabled={
              saveMutation.isPending ||
              saveCoreMutation.isPending ||
              isCoreStrictViewOnly
            }
            className="bg-blue-600 hover:bg-blue-700 text-white"
          >
            {saveMutation.isPending || saveCoreMutation.isPending ? (
              <Loader2 className="w-4 h-4 mr-2 animate-spin" />
            ) : (
              <Save className="w-4 h-4 mr-2" />
            )}
            {isCreateMode ? __("Create Template") : __("Save Template")}
          </Button>
        </div>
      </div>

      {isCoreBodyReadOnly && (
        <div className="flex items-start gap-2 rounded-lg border border-amber-200 bg-amber-50 px-4 py-3 text-sm text-amber-900 dark:border-amber-800 dark:bg-amber-950/40 dark:text-amber-100">
          <Info className="w-5 h-5 flex-shrink-0 mt-0.5" />
          <p>
            {isCoreStrictViewOnly
              ? __(
                  "This link is view-only. Subject, body, and status cannot be changed from this screen.",
                  "yatra",
                )
              : __(
                  "Subject and HTML body are read-only until the required module is active. You can still turn this email on or off below; values reflect your site settings.",
                  "yatra",
                )}
          </p>
        </div>
      )}

      <div className="grid grid-cols-1 lg:grid-cols-3 gap-6">
        {/* Main Form */}
        <div className="lg:col-span-2 space-y-6">
          <Card>
            <CardHeader>
              <CardTitle className="flex items-center justify-between">
                <span>{__("Template Details")}</span>
                <div className="flex items-center gap-2">
                  <span
                    className={`text-sm ${formData.is_active ? "text-green-600 dark:text-green-400" : "text-gray-500"}`}
                  >
                    {formData.is_active ? __("Active") : __("Inactive")}
                  </span>
                  <Switch
                    checked={formData.is_active}
                    disabled={isCoreStrictViewOnly}
                    onCheckedChange={(checked) =>
                      setFormData({ ...formData, is_active: checked })
                    }
                  />
                </div>
              </CardTitle>
            </CardHeader>
            <CardContent className="space-y-4">
              <div>
                <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
                  {__("Template Name")}
                </label>
                <Input
                  value={formData.name}
                  onChange={(e) =>
                    setFormData({ ...formData, name: e.target.value })
                  }
                  placeholder={__("Enter template name")}
                  readOnly={isCoreSettingsEdit}
                  className={
                    isCoreSettingsEdit ? "bg-gray-50 dark:bg-gray-900/40" : ""
                  }
                />
              </div>

              <div>
                <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
                  {__("Description")}
                </label>
                <Input
                  value={formData.description}
                  onChange={(e) =>
                    setFormData({ ...formData, description: e.target.value })
                  }
                  placeholder={__(
                    "Brief description of when this email is sent",
                  )}
                  readOnly={isCoreSettingsEdit}
                  className={
                    isCoreSettingsEdit ? "bg-gray-50 dark:bg-gray-900/40" : ""
                  }
                />
              </div>

              {/* Event Selector */}
              <div>
                <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
                  {__("Trigger Event")}
                </label>
                {Boolean(templateData?.is_system) || isCoreSettingsEdit ? (
                  <div className="space-y-2">
                    <div className="flex items-center gap-2">
                      <span className="inline-flex items-center gap-1.5 px-3 py-2 rounded-lg text-sm font-medium bg-indigo-100 text-indigo-800 dark:bg-indigo-900/30 dark:text-indigo-400 border border-indigo-200 dark:border-indigo-800">
                        <Zap className="w-4 h-4" />
                        {formData.event_key || "-"}
                      </span>
                      <span className="text-xs text-gray-500 dark:text-gray-400">
                        {__("System templates cannot change events")}
                      </span>
                    </div>
                    {formData.event_key && (
                      <div className="p-3 bg-indigo-50 dark:bg-indigo-900/20 rounded-lg border border-indigo-200 dark:border-indigo-800">
                        <p className="text-sm text-indigo-800 dark:text-indigo-300">
                          {events.find((e: any) => e.key === formData.event_key)
                            ?.description || ""}
                        </p>
                      </div>
                    )}
                  </div>
                ) : (
                  <div className="relative">
                    {/* Dropdown Trigger Button */}
                    <button
                      type="button"
                      onClick={() => setShowEventDropdown(!showEventDropdown)}
                      className="w-full px-3 py-2.5 border border-gray-300 dark:border-gray-600 rounded-lg bg-white dark:bg-gray-800 text-left flex items-center justify-between hover:border-gray-400 dark:hover:border-gray-500 transition-colors"
                    >
                      {formData.event_key ? (
                        <div className="flex items-center gap-2">
                          <Zap className="w-4 h-4 text-blue-500" />
                          <span className="text-sm font-medium text-gray-900 dark:text-white">
                            {events.find(
                              (e: any) => e.key === formData.event_key,
                            )?.name || formData.event_key}
                          </span>
                        </div>
                      ) : (
                        <div className="flex items-center gap-2">
                          <Mail className="w-4 h-4 text-gray-400" />
                          <span className="text-sm text-gray-500 dark:text-gray-400">
                            {__("No Event (Sequence Only)")}
                          </span>
                        </div>
                      )}
                      <ChevronDown
                        className={`w-4 h-4 text-gray-400 transition-transform ${showEventDropdown ? "rotate-180" : ""}`}
                      />
                    </button>

                    {/* Dropdown List */}
                    {showEventDropdown && (
                      <div className="absolute z-50 w-full mt-1 bg-white dark:bg-gray-800 border border-gray-200 dark:border-gray-700 rounded-lg shadow-lg max-h-80 overflow-y-auto">
                        <div className="p-2 border-b border-gray-200 dark:border-gray-700">
                          <p className="text-xs text-gray-500 dark:text-gray-400 px-2">
                            {__(
                              "Select an event to trigger this email, or leave empty for sequence use",
                            )}
                          </p>
                        </div>
                        <div className="py-1">
                          {/* None option - for templates used in sequences */}
                          <button
                            type="button"
                            onClick={() => {
                              setFormData({ ...formData, event_key: "" });
                              setShowEventDropdown(false);
                            }}
                            className={`w-full px-3 py-3 text-left hover:bg-gray-50 dark:hover:bg-gray-700 transition-colors border-b border-gray-100 dark:border-gray-700 ${
                              !formData.event_key
                                ? "bg-indigo-50 dark:bg-indigo-900/20"
                                : ""
                            }`}
                          >
                            <div className="flex items-start gap-2">
                              <Mail
                                className={`w-4 h-4 mt-0.5 flex-shrink-0 ${
                                  !formData.event_key
                                    ? "text-blue-500"
                                    : "text-gray-400"
                                }`}
                              />
                              <div className="flex-1 min-w-0">
                                <div className="flex items-center gap-2">
                                  <span
                                    className={`text-sm font-medium ${
                                      !formData.event_key
                                        ? "text-blue-800 dark:text-blue-400"
                                        : "text-gray-900 dark:text-white"
                                    }`}
                                  >
                                    {__("No Event (Sequence Only)")}
                                  </span>
                                </div>
                                <p className="text-xs text-gray-500 dark:text-gray-400 mt-0.5">
                                  {__(
                                    "This template will only be used in email sequences",
                                  )}
                                </p>
                              </div>
                              {!formData.event_key && (
                                <Check className="w-4 h-4 text-blue-500 flex-shrink-0" />
                              )}
                            </div>
                          </button>
                          {events.map((event: any) => (
                            <button
                              key={event.key}
                              type="button"
                              onClick={() => {
                                setFormData({
                                  ...formData,
                                  event_key: event.key,
                                });
                                setShowEventDropdown(false);
                              }}
                              className={`w-full px-3 py-3 text-left hover:bg-gray-50 dark:hover:bg-gray-700 transition-colors border-b border-gray-100 dark:border-gray-700 last:border-b-0 ${
                                formData.event_key === event.key
                                  ? "bg-indigo-50 dark:bg-indigo-900/20"
                                  : ""
                              }`}
                            >
                              <div className="flex items-start gap-2">
                                <Zap
                                  className={`w-4 h-4 mt-0.5 flex-shrink-0 ${
                                    formData.event_key === event.key
                                      ? "text-blue-500"
                                      : "text-gray-400"
                                  }`}
                                />
                                <div className="flex-1 min-w-0">
                                  <div className="flex items-center gap-2">
                                    <span
                                      className={`text-sm font-medium ${
                                        formData.event_key === event.key
                                          ? "text-blue-800 dark:text-blue-400"
                                          : "text-gray-900 dark:text-white"
                                      }`}
                                    >
                                      {event.name}
                                    </span>
                                    <code className="text-xs px-1.5 py-0.5 bg-gray-100 dark:bg-gray-700 text-gray-500 dark:text-gray-400 rounded">
                                      {event.key}
                                    </code>
                                  </div>
                                  <p className="text-xs text-gray-500 dark:text-gray-400 mt-0.5 line-clamp-2">
                                    {event.description}
                                  </p>
                                </div>
                                {formData.event_key === event.key && (
                                  <Check className="w-4 h-4 text-blue-500 flex-shrink-0" />
                                )}
                              </div>
                            </button>
                          ))}
                        </div>
                      </div>
                    )}

                    {/* Click outside to close */}
                    {showEventDropdown && (
                      <div
                        className="fixed inset-0 z-40"
                        onClick={() => setShowEventDropdown(false)}
                      />
                    )}
                  </div>
                )}
                <p className="text-xs text-gray-500 dark:text-gray-400 mt-1">
                  {__(
                    "This email will be triggered when the selected event occurs",
                  )}
                </p>
              </div>

              {!isCoreSettingsEdit && (
                <>
                  {/* From/Reply-To Settings */}
                  <div className="grid grid-cols-1 md:grid-cols-2 gap-4">
                    <div>
                      <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
                        {__("From Name")}
                      </label>
                      <Input
                        value={formData.from_name}
                        onChange={(e) =>
                          setFormData({
                            ...formData,
                            from_name: e.target.value,
                          })
                        }
                        placeholder={__("e.g., Travel Agency Name")}
                      />
                      <p className="text-xs text-gray-500 dark:text-gray-400 mt-1">
                        {__("Leave empty to use site default")}
                      </p>
                    </div>
                    <div>
                      <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
                        {__("From Email")}
                      </label>
                      <Input
                        type="email"
                        value={formData.from_email}
                        onChange={(e) =>
                          setFormData({
                            ...formData,
                            from_email: e.target.value,
                          })
                        }
                        placeholder={__("e.g., noreply@yoursite.com")}
                      />
                      <p className="text-xs text-gray-500 dark:text-gray-400 mt-1">
                        {__("Leave empty to use site default")}
                      </p>
                    </div>
                  </div>

                  <div className="grid grid-cols-1 md:grid-cols-2 gap-4">
                    <div>
                      <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
                        {__("To Email")}
                      </label>
                      <Input
                        type="email"
                        value={formData.to_email}
                        onChange={(e) =>
                          setFormData({ ...formData, to_email: e.target.value })
                        }
                        placeholder={__("e.g., {{customer_email}}")}
                      />
                      <p className="text-xs text-gray-500 dark:text-gray-400 mt-1">
                        {__(
                          "Recipient email. Use variables or leave empty for default",
                        )}
                      </p>
                    </div>
                    <div>
                      <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
                        {__("Reply-To Email")}
                      </label>
                      <Input
                        type="email"
                        value={formData.reply_to}
                        onChange={(e) =>
                          setFormData({ ...formData, reply_to: e.target.value })
                        }
                        placeholder={__("e.g., support@yoursite.com")}
                      />
                      <p className="text-xs text-gray-500 dark:text-gray-400 mt-1">
                        {__(
                          "Where replies will be sent. Leave empty to use From Email",
                        )}
                      </p>
                    </div>
                  </div>
                </>
              )}

              {isCoreSettingsEdit && (
                <p className="text-sm text-gray-600 dark:text-gray-400 rounded-lg border border-gray-200 dark:border-gray-600 p-3 bg-gray-50 dark:bg-gray-800/50">
                  {__(
                    "From / reply addresses are configured under Email → Delivery. Recipient uses the customer on the booking.",
                    "yatra",
                  )}
                </p>
              )}

              <div>
                <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
                  {__("Subject Line")}
                </label>
                <Input
                  value={formData.subject}
                  onChange={(e) =>
                    setFormData({ ...formData, subject: e.target.value })
                  }
                  placeholder={__("Email subject with {{variables}}")}
                  readOnly={isCoreBodyReadOnly}
                  className={`font-mono text-sm ${isCoreBodyReadOnly ? "bg-gray-50 dark:bg-gray-900/40" : ""}`}
                />
                <p className="text-xs text-gray-500 dark:text-gray-400 mt-1">
                  {__("Use {{variable}} syntax to insert dynamic content")}
                </p>
              </div>

              <div>
                {/* Label + AI sparkle on the same row — sparkle sits
                    to the right of the "Email Body (HTML)" label so
                    it's visually associated with the editor it
                    affects, not floating above Subject Line. */}
                <div className="mb-1 flex items-center justify-between">
                  <label className="block text-sm font-medium text-gray-700 dark:text-gray-300">
                    {__("Email Body (HTML)")}
                  </label>
                  {!isCoreBodyReadOnly &&
                    isAiEligible() &&
                    isAiModuleEnabled() && (
                      <Button
                        type="button"
                        variant="outline"
                        size="sm"
                        onClick={() => setShowAiModal(true)}
                        className="border-blue-300 text-blue-700 hover:bg-blue-50 dark:border-blue-500/40 dark:text-blue-200 dark:hover:bg-blue-900/30"
                      >
                        <Sparkles className="mr-1.5 h-3.5 w-3.5" />
                        {__("Generate with AI", "yatra")}
                      </Button>
                    )}
                </div>
                <textarea
                  id="email-body"
                  value={formData.body}
                  onChange={(e) =>
                    setFormData({ ...formData, body: e.target.value })
                  }
                  rows={20}
                  readOnly={isCoreBodyReadOnly}
                  className={`w-full px-3 py-2 border border-gray-300 dark:border-gray-600 rounded-lg font-mono text-sm ${
                    isCoreBodyReadOnly
                      ? "bg-gray-50 dark:bg-gray-900/40 text-gray-900 dark:text-white"
                      : "bg-white dark:bg-gray-800 text-gray-900 dark:text-white"
                  }`}
                  placeholder={__("HTML email content...")}
                />
              </div>
            </CardContent>
          </Card>

          {/* Test Email - Only show in edit mode */}
          {!isCreateMode && !isCoreSettingsEdit && (
            <Card>
              <CardHeader>
                <CardTitle className="flex items-center gap-2">
                  <Send className="w-5 h-5 text-blue-500" />
                  {__("Send Test Email")}
                </CardTitle>
              </CardHeader>
              <CardContent>
                <div className="flex gap-3">
                  <Input
                    type="email"
                    value={testEmail}
                    onChange={(e) => setTestEmail(e.target.value)}
                    placeholder={__("Enter email address")}
                    className="flex-1"
                  />
                  <Button
                    onClick={() => testMutation.mutate(testEmail)}
                    disabled={!testEmail || testMutation.isPending}
                  >
                    {testMutation.isPending ? (
                      <Loader2 className="w-4 h-4 animate-spin" />
                    ) : (
                      <Send className="w-4 h-4" />
                    )}
                  </Button>
                </div>
                <p className="text-xs text-gray-500 dark:text-gray-400 mt-2">
                  {__(
                    "Send a test email with sample data to preview how it looks",
                  )}
                </p>
              </CardContent>
            </Card>
          )}
        </div>

        {/* Sidebar - Variables */}
        <div className="space-y-6">
          <Card>
            <CardHeader>
              <CardTitle className="flex items-center gap-2">
                <Code className="w-5 h-5 text-blue-500" />
                {__("Available Variables")}
              </CardTitle>
            </CardHeader>
            <CardContent className="space-y-4">
              {!isCoreSettingsEdit && (
                <>
                  <p className="text-sm text-gray-500 dark:text-gray-400">
                    {__("Click to copy, double-click to insert at cursor")}
                  </p>
                  {/*
                    Subtitle showing which event the variables list is
                    scoped to. Without this hint, operators see a
                    different set of tags every time they switch the
                    event dropdown and have no clear explanation why.
                  */}
                  {formData.event_key ? (
                    // Show the technical event KEY (dot-notation, monospace)
                    // as the primary label so it can't be confused with the
                    // template's display title — earlier versions showed
                    // the event's friendly name, which often matches what
                    // operators name their templates ("Customer email
                    // verification" appears as both the event name and a
                    // common template title) and made it unclear what the
                    // chip was scoped to. Friendly name still appears as
                    // the parenthesised clarifier.
                    <p className="text-xs text-blue-700 dark:text-blue-300 bg-blue-50 dark:bg-blue-950/30 rounded px-2 py-1.5">
                      {__("Variables available for trigger event:", "yatra")}{" "}
                      <code className="font-mono text-blue-800 dark:text-blue-200 bg-blue-100 dark:bg-blue-900/40 px-1 rounded">
                        {formData.event_key}
                      </code>
                      {(() => {
                        const match = events.find(
                          (e: any) => e.key === formData.event_key,
                        );
                        return match?.name ? (
                          <span className="text-blue-600/80 dark:text-blue-400/80">
                            {" "}
                            ({match.name})
                          </span>
                        ) : null;
                      })()}
                    </p>
                  ) : (
                    <p className="text-xs text-amber-700 dark:text-amber-400 bg-amber-50 dark:bg-amber-950/30 rounded px-2 py-1.5">
                      {__(
                        "Pick a trigger event below to see the variables that apply to that event. Showing the full catalog until then.",
                        "yatra",
                      )}
                    </p>
                  )}
                </>
              )}

              {isCoreSettingsEdit && coreDef?.mergeTags ? (
                <div className="space-y-2">
                  <p className="text-xs font-semibold text-gray-500 dark:text-gray-400 uppercase">
                    {__("Merge tags", "yatra")}
                  </p>
                  <p className="text-xs text-gray-500 dark:text-gray-400">
                    {__(
                      "Click a tag to copy; paste into subject or HTML body.",
                      "yatra",
                    )}
                  </p>
                  <div className="flex flex-wrap gap-1">
                    {coreDef.mergeTags.split(",").map((raw) => {
                      const tag = raw.trim();
                      const inner = tag.replace(/\{\{|\}\}/g, "").trim();
                      if (!inner) return null;
                      return (
                        <button
                          key={tag}
                          type="button"
                          onClick={() => copyVariable(inner)}
                          className="rounded border border-gray-200 dark:border-gray-600 px-2 py-1 text-xs font-mono text-blue-600 dark:text-blue-400 hover:bg-gray-50 dark:hover:bg-gray-800"
                        >
                          {tag}
                        </button>
                      );
                    })}
                  </div>
                </div>
              ) : (
                variablesData &&
                Object.entries(variablesData).map(
                  ([category, variables]: [string, any]) => (
                    <div key={category}>
                      <h4 className="text-xs font-semibold text-gray-500 dark:text-gray-400 uppercase mb-2">
                        {category}
                      </h4>
                      <div className="space-y-1">
                        {variables.map((v: any) => (
                          <button
                            key={v.key}
                            type="button"
                            onClick={() => copyVariable(v.key)}
                            onDoubleClick={() => insertVariable(v.key)}
                            className="w-full text-left px-2 py-1.5 rounded hover:bg-gray-100 dark:hover:bg-gray-800 transition-colors group"
                          >
                            <div className="flex items-center justify-between">
                              <code className="text-xs text-blue-600 dark:text-blue-400">
                                {`{{${v.key}}}`}
                              </code>
                              {copiedVar === v.key ? (
                                <Check className="w-3 h-3 text-green-500" />
                              ) : (
                                <Copy className="w-3 h-3 text-gray-400 opacity-0 group-hover:opacity-100" />
                              )}
                            </div>
                            <p className="text-xs text-gray-500 dark:text-gray-400 mt-0.5">
                              {v.description}
                            </p>
                          </button>
                        ))}
                      </div>
                    </div>
                  ),
                )
              )}
            </CardContent>
          </Card>

          {/* Template Info - Different content for create vs edit */}
          <Card>
            <CardHeader>
              <CardTitle className="flex items-center gap-2">
                <Info className="w-5 h-5 text-gray-500" />
                {isCreateMode ? __("New Template") : __("Template Info")}
              </CardTitle>
            </CardHeader>
            <CardContent className="space-y-3 text-sm">
              <div className="space-y-2">
                <div className="flex justify-between items-center">
                  <span className="text-gray-500 dark:text-gray-400">
                    {__("Event")}
                  </span>
                  <span className="inline-flex items-center gap-1.5 px-2 py-1 rounded-full text-xs font-medium bg-indigo-100 text-indigo-800 dark:bg-indigo-900/30 dark:text-indigo-400">
                    <Zap className="w-3 h-3" />
                    {formData.event_key || "-"}
                  </span>
                </div>
                {formData.event_key && (
                  <p className="text-xs text-gray-500 dark:text-gray-400 italic">
                    {events.find((e: any) => e.key === formData.event_key)
                      ?.description || ""}
                  </p>
                )}
              </div>
              {isCreateMode ? (
                <>
                  <div className="flex justify-between">
                    <span className="text-gray-500 dark:text-gray-400">
                      {__("Type")}
                    </span>
                    <span className="text-gray-900 dark:text-white">
                      {__("Custom")}
                    </span>
                  </div>
                  <div className="p-3 bg-blue-50 dark:bg-blue-900/20 rounded-lg border border-blue-200 dark:border-blue-800">
                    <p className="text-xs text-blue-700 dark:text-blue-300">
                      {__(
                        "Custom templates can be edited and deleted. Select an event to trigger this email automatically.",
                      )}
                    </p>
                  </div>
                </>
              ) : (
                <>
                  <div className="flex justify-between">
                    <span className="text-gray-500 dark:text-gray-400">
                      {__("Key")}
                    </span>
                    <code className="text-xs bg-gray-100 dark:bg-gray-800 px-2 py-0.5 rounded">
                      {isCoreSettingsEdit
                        ? coreDef?.template_key
                        : String(templateData?.template_key ?? "")}
                    </code>
                  </div>
                  <div className="flex justify-between">
                    <span className="text-gray-500 dark:text-gray-400">
                      {__("Category")}
                    </span>
                    <Badge className="bg-blue-100 text-blue-700 dark:bg-blue-900/30 dark:text-blue-400">
                      {isCoreSettingsEdit
                        ? coreDef?.category
                        : String(templateData?.category ?? "")}
                    </Badge>
                  </div>
                  <div className="flex justify-between">
                    <span className="text-gray-500 dark:text-gray-400">
                      {__("Recipient")}
                    </span>
                    <span
                      className={`inline-flex items-center px-2 py-0.5 rounded-full text-xs font-medium ${
                        (isCoreSettingsEdit
                          ? coreDef?.recipient_type
                          : String(templateData?.recipient_type ?? "")) ===
                        "admin"
                          ? "bg-orange-100 text-orange-700 dark:bg-orange-900/30 dark:text-orange-400"
                          : "bg-blue-100 text-blue-700 dark:bg-blue-900/30 dark:text-blue-400"
                      }`}
                    >
                      {(isCoreSettingsEdit
                        ? coreDef?.recipient_type
                        : String(templateData?.recipient_type ?? "")) ===
                      "admin"
                        ? __("Admin")
                        : __("Customer")}
                    </span>
                  </div>
                  <div className="flex justify-between">
                    <span className="text-gray-500 dark:text-gray-400">
                      {__("Type")}
                    </span>
                    <span className="text-gray-900 dark:text-white">
                      {isCoreSettingsEdit || Boolean(templateData?.is_system)
                        ? __("System")
                        : __("Custom")}
                    </span>
                  </div>
                </>
              )}
            </CardContent>
          </Card>
        </div>
      </div>

      <EmailPreviewModal
        open={showPreview && Boolean(previewData)}
        onClose={() => {
          setShowPreview(false);
          setPreviewData(null);
        }}
        subject={previewData?.subject ?? ""}
        body={previewData?.body ?? ""}
      />

      {/* AI: subject + body generator. The merge-tag list comes from
          the catalog entry when it's a core template, falling back
          to a sensible default set when editing a custom template. */}
      <AiEmailTemplateModal
        open={showAiModal}
        onClose={() => setShowAiModal(false)}
        templateKey={
          coreTemplateSlug || formData.event_key || "custom_template"
        }
        templateName={coreDef?.name || formData.name || formData.event_key}
        templateDescription={coreDef?.description || formData.description}
        recipientType={
          (catalogEntryForCore?.recipient_type as "customer" | "admin") ||
          "customer"
        }
        mergeTags={(() => {
          // Catalog stores mergeTags as a comma-string like
          // "{{customer_name}}, {{booking_reference}}, …". Coerce to
          // the bare tag names ('customer_name') that the agent's
          // server-side normalizer accepts.
          const raw = catalogEntryForCore?.mergeTags ?? "";
          if (!raw) {
            return [
              "site_name",
              "site_url",
              "customer_name",
              "customer_email",
              "booking_reference",
              "trip_name",
              "travel_date",
              "total_amount",
              "currency",
            ];
          }
          return raw
            .split(",")
            .map((s) =>
              s
                .trim()
                .replace(/^\{\{|\}\}$/g, "")
                .trim(),
            )
            .filter(Boolean);
        })()}
        currentSubject={formData.subject}
        currentBody={formData.body}
        onAccept={({ subject, body }) =>
          setFormData({ ...formData, subject, body })
        }
      />
    </div>
  );
};

export default EmailTemplateForm;