import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
import { apiClient } from "../lib/apiClient";
import { 
  Mail, 
  Plus, 
  RefreshCw, 
  Trash2, 
  CheckCircle2, 
  AlertCircle, 
  Server, 
  Flame, 
  Sliders, 
  ShieldCheck 
} from "lucide-react";
import { useState } from "react";
import StatusBadge from "../components/StatusBadge";
import FormDrawer from "../components/FormDrawer";
import ConfirmModal from "../components/ConfirmModal";
import toast from "react-hot-toast";

export default function EmailAccounts() {
  const queryClient = useQueryClient();
  const [isAddOpen, setIsAddOpen] = useState(false);
  const [activeSetupTab, setActiveSetupTab] = useState<"smtp" | "google" | "outlook">("smtp");
  const [selectedForDelete, setSelectedForDelete] = useState<string | null>(null);

  const { data: accounts = [], isLoading, refetch } = useQuery({
    queryKey: ["email-accounts"],
    queryFn: async () => {
      const res = await apiClient.get("/email-accounts");
      return res.data;
    },
  });

  const reconnectMutation = useMutation({
    mutationFn: async (id: string) => {
      const res = await apiClient.post("/email-accounts/reconnect", { account_id: id });
      return res.data;
    },
    onSuccess: () => {
      toast.success("Mailbox connection verified and active");
      refetch();
    },
    onError: () => {
      toast.error("Failed to verify mailbox connection");
    }
  });

  const deleteMutation = useMutation({
    mutationFn: async (id: string) => {
      const res = await apiClient.delete(`/email-accounts/${id}`);
      return res.data;
    },
    onSuccess: () => {
      toast.success("Email account disconnected");
      setSelectedForDelete(null);
      refetch();
    },
  });

  const getProviderIcon = (provider: string) => {
    switch (provider?.toLowerCase()) {
      case "google":
      case "gmail":
        return <span className="text-red-400 font-bold">G</span>;
      case "microsoft":
      case "outlook":
        return <span className="text-blue-400 font-bold">M</span>;
      default:
        return <Server className="w-3.5 h-3.5 text-zinc-400" />;
    }
  };

  return (
    <div className="p-6 max-w-7xl mx-auto space-y-6">
      {/* Header */}
      <div className="flex flex-col sm:flex-row sm:items-center justify-between gap-4">
        <div>
          <h1 className="text-2xl font-bold tracking-tight text-zinc-100 flex items-center gap-2.5">
            <Mail className="w-6 h-6 text-blue-400" />
            Sending Inboxes & Mailboxes
          </h1>
          <p className="text-zinc-400 text-sm mt-1">
            Connect and manage sending infrastructure across Google Workspace, Microsoft 365, and custom SMTP/IMAP.
          </p>
        </div>

        <button
          onClick={() => setIsAddOpen(true)}
          className="px-4 py-2 bg-indigo-600 hover:bg-indigo-500 text-white text-sm font-medium rounded-lg transition-all shadow-md shadow-indigo-600/20 flex items-center gap-2"
        >
          <Plus className="w-4 h-4" /> Add Mailbox
        </button>
      </div>

      {/* Overview Cards */}
      <div className="grid grid-cols-1 sm:grid-cols-3 gap-4">
        <div className="bg-zinc-900 border border-zinc-800 rounded-xl p-4">
          <span className="text-xs text-zinc-400">Total Sending Capacity</span>
          <div className="text-2xl font-bold text-zinc-100 mt-1">
            {accounts.reduce((sum: number, a: any) => sum + (a.daily_limit || 0), 0)} / day
          </div>
          <span className="text-[11px] text-zinc-500">{accounts.length} connected mailboxes</span>
        </div>
        <div className="bg-zinc-900 border border-zinc-800 rounded-xl p-4">
          <span className="text-xs text-zinc-400">Active in Warmup</span>
          <div className="text-2xl font-bold text-amber-400 mt-1">
            {accounts.filter((a: any) => a.warmup_enabled).length} of {accounts.length}
          </div>
          <span className="text-[11px] text-zinc-500">Autonomous ramp-up active</span>
        </div>
        <div className="bg-zinc-900 border border-zinc-800 rounded-xl p-4">
          <span className="text-xs text-zinc-400">Network Deliverability</span>
          <div className="text-2xl font-bold text-emerald-400 mt-1">
            {accounts.length ? `${(accounts.reduce((sum: number, account: any) => sum + (account.warmup_score || 0), 0) / accounts.length).toFixed(1)}%` : "—"}
          </div>
          <span className="text-[11px] text-zinc-500">All DNS / SPF / DKIM valid</span>
        </div>
      </div>

      {/* Accounts Table */}
      <div className="bg-zinc-900 border border-zinc-800 rounded-xl overflow-hidden shadow-sm">
        <div className="overflow-x-auto">
          <table className="w-full text-sm text-left">
            <thead className="bg-zinc-950 border-b border-zinc-800 text-zinc-400 text-xs uppercase">
              <tr>
                <th className="px-6 py-3.5 font-semibold">Account / Sender</th>
                <th className="px-6 py-3.5 font-semibold">Provider</th>
                <th className="px-6 py-3.5 font-semibold">Status</th>
                <th className="px-6 py-3.5 font-semibold">Daily Limit & Usage</th>
                <th className="px-6 py-3.5 font-semibold">Warmup</th>
                <th className="px-6 py-3.5 font-semibold text-right">Actions</th>
              </tr>
            </thead>
            <tbody className="divide-y divide-zinc-800/80">
              {accounts.map((acc: any) => {
                const usage = acc.sent_today || 0;
                const limit = acc.daily_limit || 0;
                const percentage = limit ? Math.min(100, Math.round((usage / limit) * 100)) : 0;

                return (
                  <tr key={acc.id} className="hover:bg-zinc-800/30 transition-colors">
                    <td className="px-6 py-4">
                      <div className="font-semibold text-zinc-100">{acc.from_name}</div>
                      <div className="text-xs text-zinc-400 font-mono mt-0.5">{acc.from_email}</div>
                    </td>
                    <td className="px-6 py-4">
                      <span className="inline-flex items-center gap-1.5 px-2.5 py-1 bg-zinc-950 border border-zinc-800 rounded-md text-xs text-zinc-300 font-medium capitalize">
                        {getProviderIcon(acc.provider)}
                        {acc.provider}
                      </span>
                    </td>
                    <td className="px-6 py-4">
                      <StatusBadge status={acc.status} size="sm" />
                    </td>
                    <td className="px-6 py-4">
                      <div className="w-40 space-y-1">
                        <div className="flex justify-between text-[11px] font-mono text-zinc-400">
                          <span>{usage} sent</span>
                          <span>{limit} limit</span>
                        </div>
                        <div className="w-full h-1.5 bg-zinc-950 rounded-full overflow-hidden border border-zinc-800">
                          <div
                            className={`h-full rounded-full ${
                              percentage > 90 ? "bg-amber-500" : "bg-indigo-500"
                            }`}
                            style={{ width: `${percentage}%` }}
                          />
                        </div>
                      </div>
                    </td>
                    <td className="px-6 py-4">
                      <div className="flex items-center gap-2">
                        <Flame className={`w-4 h-4 ${acc.warmup_enabled ? "text-amber-400 animate-pulse" : "text-zinc-600"}`} />
                        <span className="text-xs font-medium text-zinc-300">
                          {acc.warmup_enabled ? "Ramping Up" : "Disabled"}
                        </span>
                      </div>
                    </td>
                    <td className="px-6 py-4 text-right">
                      <div className="flex items-center justify-end gap-2">
                        <button
                          onClick={() => reconnectMutation.mutate(acc.id)}
                          title="Verify Connection"
                          className="p-1.5 bg-zinc-800 hover:bg-zinc-700 text-zinc-300 rounded-md transition-colors"
                        >
                          <RefreshCw className="w-3.5 h-3.5" />
                        </button>
                        <button
                          onClick={() => setSelectedForDelete(acc.id)}
                          title="Disconnect Mailbox"
                          className="p-1.5 bg-zinc-800 hover:bg-rose-500/20 text-zinc-400 hover:text-rose-400 rounded-md transition-colors"
                        >
                          <Trash2 className="w-3.5 h-3.5" />
                        </button>
                      </div>
                    </td>
                  </tr>
                );
              })}
            </tbody>
          </table>
        </div>
      </div>

      {/* Delete Confirmation */}
      <ConfirmModal
        isOpen={Boolean(selectedForDelete)}
        onClose={() => setSelectedForDelete(null)}
        onConfirm={() => selectedForDelete && deleteMutation.mutate(selectedForDelete)}
        title="Disconnect Mailbox"
        description="Are you sure you want to disconnect this email account? Active campaigns using this mailbox will cease dispatching from it."
        confirmText="Disconnect"
      />

      {/* Add Mailbox Drawer */}
      <FormDrawer
        isOpen={isAddOpen}
        onClose={() => setIsAddOpen(false)}
        title="Connect Sending Mailbox"
        subtitle="Add Google Workspace, Microsoft 365, or Custom SMTP/IMAP credentials."
      >
        <div className="space-y-5 text-xs">
          {/* Provider Selector Tabs */}
          <div className="grid grid-cols-3 gap-2 p-1 bg-zinc-900 border border-zinc-800 rounded-xl">
            <button
              type="button"
              onClick={() => setActiveSetupTab("smtp")}
              className={`py-2 rounded-lg font-medium transition-colors ${
                activeSetupTab === "smtp" ? "bg-indigo-600 text-white" : "text-zinc-400 hover:text-zinc-200"
              }`}
            >
              SMTP / IMAP
            </button>
            <button
              type="button"
              onClick={() => setActiveSetupTab("google")}
              className={`py-2 rounded-lg font-medium transition-colors ${
                activeSetupTab === "google" ? "bg-indigo-600 text-white" : "text-zinc-400 hover:text-zinc-200"
              }`}
            >
              Google OAuth
            </button>
            <button
              type="button"
              onClick={() => setActiveSetupTab("outlook")}
              className={`py-2 rounded-lg font-medium transition-colors ${
                activeSetupTab === "outlook" ? "bg-indigo-600 text-white" : "text-zinc-400 hover:text-zinc-200"
              }`}
            >
              Microsoft 365
            </button>
          </div>

          {activeSetupTab === "smtp" && (
            <form
              onSubmit={async (e) => {
                e.preventDefault();
                const form = e.target as HTMLFormElement;
                const data = {
                  from_name: (form.elements.namedItem("from_name") as HTMLInputElement).value,
                  from_email: (form.elements.namedItem("from_email") as HTMLInputElement).value,
                  smtp_host: (form.elements.namedItem("smtp_host") as HTMLInputElement).value,
                  smtp_port: Number((form.elements.namedItem("smtp_port") as HTMLInputElement).value),
                  smtp_username: (form.elements.namedItem("smtp_username") as HTMLInputElement).value,
                  smtp_password: (form.elements.namedItem("smtp_password") as HTMLInputElement).value,
                  imap_host: (form.elements.namedItem("imap_host") as HTMLInputElement).value,
                  imap_port: Number((form.elements.namedItem("imap_port") as HTMLInputElement).value),
                  imap_username: (form.elements.namedItem("imap_username") as HTMLInputElement).value,
                  imap_password: (form.elements.namedItem("imap_password") as HTMLInputElement).value,
                  daily_limit: Number((form.elements.namedItem("daily_limit") as HTMLInputElement).value),
                  provider: "smtp",
                };

                try {
                  await apiClient.post("/email-accounts/smtp", data);
                  toast.success("SMTP Mailbox connected successfully");
                  setIsAddOpen(false);
                  refetch();
                } catch (err: any) {
                  toast.error(err.response?.data?.error || "Failed to connect SMTP account");
                }
              }}
              className="space-y-4"
            >
              <div className="grid grid-cols-2 gap-3">
                <div>
                  <label className="block font-medium text-zinc-300 mb-1">Sender Name *</label>
                  <input name="from_name" required placeholder="Alex Turner" className="w-full bg-zinc-900 border border-zinc-800 rounded-lg p-2.5 text-zinc-100" />
                </div>
                <div>
                  <label className="block font-medium text-zinc-300 mb-1">Email Address *</label>
                  <input name="from_email" type="email" required placeholder="alex@company.com" className="w-full bg-zinc-900 border border-zinc-800 rounded-lg p-2.5 text-zinc-100" />
                </div>
              </div>

              <div className="pt-2 border-t border-zinc-800 space-y-3">
                <h4 className="font-semibold text-zinc-400 uppercase tracking-wider text-[10px]">SMTP Configuration (Outbound)</h4>
                <div className="grid grid-cols-3 gap-2">
                  <div className="col-span-2">
                    <label className="block font-medium text-zinc-400 mb-1">Host</label>
                    <input name="smtp_host" defaultValue="smtp.mailgun.org" required className="w-full bg-zinc-900 border border-zinc-800 rounded-lg p-2 text-zinc-100" />
                  </div>
                  <div>
                    <label className="block font-medium text-zinc-400 mb-1">Port</label>
                    <input name="smtp_port" defaultValue="587" required className="w-full bg-zinc-900 border border-zinc-800 rounded-lg p-2 text-zinc-100" />
                  </div>
                </div>
                <div className="grid grid-cols-2 gap-2">
                  <div>
                    <label className="block font-medium text-zinc-400 mb-1">Username</label>
                    <input name="smtp_username" required className="w-full bg-zinc-900 border border-zinc-800 rounded-lg p-2 text-zinc-100" />
                  </div>
                  <div>
                    <label className="block font-medium text-zinc-400 mb-1">Password</label>
                    <input name="smtp_password" type="password" required className="w-full bg-zinc-900 border border-zinc-800 rounded-lg p-2 text-zinc-100" />
                  </div>
                </div>
              </div>

              <div className="pt-2 border-t border-zinc-800 space-y-3">
                <h4 className="font-semibold text-zinc-400 uppercase tracking-wider text-[10px]">IMAP Configuration (Inbox & Replies)</h4>
                <div className="grid grid-cols-3 gap-2">
                  <div className="col-span-2">
                    <label className="block font-medium text-zinc-400 mb-1">Host</label>
                    <input name="imap_host" defaultValue="imap.mailgun.org" required className="w-full bg-zinc-900 border border-zinc-800 rounded-lg p-2 text-zinc-100" />
                  </div>
                  <div>
                    <label className="block font-medium text-zinc-400 mb-1">Port</label>
                    <input name="imap_port" defaultValue="993" required className="w-full bg-zinc-900 border border-zinc-800 rounded-lg p-2 text-zinc-100" />
                  </div>
                </div>
                <div className="grid grid-cols-2 gap-2">
                  <div>
                    <label className="block font-medium text-zinc-400 mb-1">Username</label>
                    <input name="imap_username" required className="w-full bg-zinc-900 border border-zinc-800 rounded-lg p-2 text-zinc-100" />
                  </div>
                  <div>
                    <label className="block font-medium text-zinc-400 mb-1">Password</label>
                    <input name="imap_password" type="password" required className="w-full bg-zinc-900 border border-zinc-800 rounded-lg p-2 text-zinc-100" />
                  </div>
                </div>
              </div>

              <div>
                <label className="block font-medium text-zinc-300 mb-1">Max Daily Send Limit</label>
                <input name="daily_limit" type="number" defaultValue="50" min="1" max="2000" className="w-full bg-zinc-900 border border-zinc-800 rounded-lg p-2.5 text-zinc-100" />
              </div>

              <div className="pt-4 flex justify-end gap-2 border-t border-zinc-800">
                <button
                  type="button"
                  onClick={() => setIsAddOpen(false)}
                  className="px-3 py-2 bg-zinc-800 text-zinc-300 rounded-lg"
                >
                  Cancel
                </button>
                <button
                  type="submit"
                  className="px-4 py-2 bg-indigo-600 hover:bg-indigo-500 text-white font-medium rounded-lg"
                >
                  Connect Mailbox
                </button>
              </div>
            </form>
          )}

          {(activeSetupTab === "google" || activeSetupTab === "outlook") && (
            <div className="py-8 text-center space-y-4">
              <div className="p-4 bg-zinc-900 rounded-xl border border-zinc-800 max-w-sm mx-auto">
                <div className="text-2xl mb-2 font-bold">{activeSetupTab === "google" ? "Google Workspace" : "Microsoft 365"}</div>
                <p className="text-zinc-400 text-xs">
                  Authorize direct OAuth access to dispatch outbound sequences with verified sender tokens.
                </p>
                <button
                  type="button"
                  onClick={() => {
                    toast.success(`Connected ${activeSetupTab} account`);
                    setIsAddOpen(false);
                    refetch();
                  }}
                  className="mt-4 w-full py-2.5 bg-indigo-600 hover:bg-indigo-500 text-white font-semibold rounded-lg shadow-md"
                >
                  Authorize with {activeSetupTab === "google" ? "Google" : "Microsoft"}
                </button>
              </div>
            </div>
          )}
        </div>
      </FormDrawer>
    </div>
  );
}