"use client";
import { useEffect, useMemo, useState } from "react";
import { useAuth } from "@/hooks/useAuth";
import { api, type Finding } from "@/lib/api";
import Sidebar from "@/components/Sidebar";
import Link from "next/link";
import { Shield, Filter, ArrowUpDown, CheckCircle2, Search, Download } from "lucide-react";

const SEVERITY_ORDER: Record<string, number> = { critical: 0, high: 1, medium: 2, low: 3, info: 4 };
const STATUS_COLORS: Record<string, string> = {
  open: "vault-badge-critical",
  in_progress: "vault-badge-medium",
  resolved: "vault-badge-low",
  verified: "vault-badge-info",
  accepted_risk: "vault-badge-info",
};
const CATEGORY_LABELS: Record<string, string> = {
  external_exposure: "External Exposure",
  cloud_posture: "Cloud Posture",
  credential_exposure: "Credential Exposure",
  digital_footprint: "Digital Footprint",
  web_application: "Web Application",
  network: "Network",
  identity: "Identity",
  third_party: "Third Party",
  compliance: "Compliance",
  other: "Other",
};

type SortKey = "severity" | "created" | "title";

export default function FindingsPage() {
  const { tenantId, ready } = useAuth();
  const [findings, setFindings] = useState<Finding[]>([]);
  const [loading, setLoading] = useState(true);
  const [filterSeverity, setFilterSeverity] = useState("all");
  const [filterStatus, setFilterStatus] = useState("open");
  const [query, setQuery] = useState("");
  const [sortKey, setSortKey] = useState<SortKey>("severity");

  useEffect(() => {
    if (!ready || !tenantId) return;
    const params = [
      filterSeverity !== "all" ? `severity=${filterSeverity}` : "",
      filterStatus !== "all" ? `status=${filterStatus}` : "",
    ].filter(Boolean).join("&");
    api.findings(tenantId, params)
      .then(setFindings)
      .finally(() => setLoading(false));
  }, [ready, tenantId, filterSeverity, filterStatus]);

  const visible = useMemo(() => {
    let list = findings;
    if (query.trim()) {
      const q = query.toLowerCase();
      list = list.filter(f =>
        f.title.toLowerCase().includes(q) ||
        (f.ai_summary ?? "").toLowerCase().includes(q) ||
        (f.affected_component ?? "").toLowerCase().includes(q) ||
        (f.cve_id ?? "").toLowerCase().includes(q)
      );
    }
    return [...list].sort((a, b) => {
      if (sortKey === "severity") {
        return (SEVERITY_ORDER[a.severity] ?? 9) - (SEVERITY_ORDER[b.severity] ?? 9);
      }
      if (sortKey === "created") {
        return new Date(b.created_at).getTime() - new Date(a.created_at).getTime();
      }
      return a.title.localeCompare(b.title);
    });
  }, [findings, query, sortKey]);

  const counts = useMemo(() => {
    const c: Record<string, number> = { critical: 0, high: 0, medium: 0, low: 0 };
    for (const f of findings) if (f.severity in c) c[f.severity]++;
    return c;
  }, [findings]);

  function exportCsv() {
    const header = ["Title", "Severity", "Status", "Category", "CVE", "CVSS", "Component", "Created"];
    const rows = visible.map(f => [
      f.title, f.severity, f.status, f.category,
      f.cve_id ?? "", f.cvss_score ?? "", f.affected_component ?? "",
      new Date(f.created_at).toISOString().slice(0, 10),
    ]);
    const csv = [header, ...rows]
      .map(r => r.map(v => `"${String(v).replace(/"/g, '""')}"`).join(","))
      .join("\n");
    const blob = new Blob([csv], { type: "text/csv" });
    const url = URL.createObjectURL(blob);
    const a = document.createElement("a");
    a.href = url;
    a.download = "trustos_findings.csv";
    a.click();
    URL.revokeObjectURL(url);
  }

  return (
    <div className="flex min-h-screen bg-vault-black">
      <Sidebar />
      <main className="ml-64 flex-1 p-8">
        <div className="mb-6 flex items-center justify-between">
          <div>
            <h1 className="text-2xl font-bold text-vault-text flex items-center gap-2">
              <Shield className="w-6 h-6 text-vault-sapphire" />
              Findings
            </h1>
            <p className="text-vault-muted text-sm mt-0.5">All security findings across your environment</p>
          </div>
          <div className="flex items-center gap-3">
            <div className="flex items-center gap-2">
              {(["critical", "high", "medium", "low"] as const).map(s => (
                counts[s] > 0 && (
                  <span key={s} className={`vault-badge-${s}`}>{counts[s]} {s}</span>
                )
              ))}
            </div>
            <button onClick={exportCsv} className="btn-ghost border border-vault-border rounded-lg" title="Export CSV">
              <Download className="w-4 h-4" /> CSV
            </button>
          </div>
        </div>

        {/* Search + sort */}
        <div className="flex gap-3 mb-4 items-center flex-wrap">
          <div className="relative flex-1 min-w-64 max-w-md">
            <Search className="w-4 h-4 text-vault-muted absolute left-3 top-1/2 -translate-y-1/2" />
            <input
              value={query}
              onChange={e => setQuery(e.target.value)}
              placeholder="Search title, CVE, component…"
              className="w-full pl-9 pr-3.5 py-2 rounded-lg bg-vault-dark border border-vault-border text-vault-text placeholder-vault-muted text-sm focus:outline-none focus:border-vault-sapphire"
            />
          </div>
          <div className="flex items-center gap-2">
            <ArrowUpDown className="w-4 h-4 text-vault-muted" />
            <select
              value={sortKey}
              onChange={e => setSortKey(e.target.value as SortKey)}
              className="px-3 py-2 rounded-lg bg-vault-dark border border-vault-border text-vault-text text-sm focus:outline-none focus:border-vault-sapphire"
            >
              <option value="severity">Sort: Severity</option>
              <option value="created">Sort: Newest</option>
              <option value="title">Sort: Title</option>
            </select>
          </div>
        </div>

        {/* Filters */}
        <div className="flex gap-3 mb-6 flex-wrap">
          <div className="flex items-center gap-2">
            <Filter className="w-4 h-4 text-vault-muted" />
            <span className="text-vault-muted text-sm">Filter:</span>
          </div>
          {["all", "critical", "high", "medium", "low"].map(s => (
            <button
              key={s}
              onClick={() => { setFilterSeverity(s); setLoading(true); }}
              className={`px-3 py-1 rounded-full text-xs font-semibold border transition-colors ${
                filterSeverity === s
                  ? "bg-vault-sapphire text-white border-vault-sapphire"
                  : "bg-vault-surface border-vault-border text-vault-muted hover:text-vault-text"
              }`}
            >
              {s === "all" ? "All Severities" : s.toUpperCase()}
            </button>
          ))}
          <div className="border-l border-vault-border mx-1" />
          {["all", "open", "in_progress", "resolved", "verified"].map(s => (
            <button
              key={s}
              onClick={() => { setFilterStatus(s); setLoading(true); }}
              className={`px-3 py-1 rounded-full text-xs font-semibold border transition-colors ${
                filterStatus === s
                  ? "bg-vault-sapphire text-white border-vault-sapphire"
                  : "bg-vault-surface border-vault-border text-vault-muted hover:text-vault-text"
              }`}
            >
              {s === "all" ? "All Statuses" : s.replace("_", " ")}
            </button>
          ))}
          <span className="ml-auto text-vault-muted text-sm self-center">{visible.length} results</span>
        </div>

        {/* Findings table */}
        <div className="vault-card overflow-hidden p-0">
          {loading ? (
            <div className="flex items-center justify-center h-40">
              <div className="animate-spin w-6 h-6 border-2 border-vault-sapphire border-t-transparent rounded-full" />
            </div>
          ) : visible.length === 0 ? (
            <div className="text-center py-16">
              <CheckCircle2 className="w-10 h-10 text-emerald-400 mx-auto mb-3" />
              <p className="text-vault-text font-semibold">No findings match these filters</p>
            </div>
          ) : (
            <table className="w-full">
              <thead>
                <tr className="border-b border-vault-border">
                  {["Severity", "Title", "Category", "Status", "Priority", ""].map(h => (
                    <th key={h} className="px-5 py-3 text-left text-xs font-semibold text-vault-muted uppercase tracking-wider">
                      {h}
                    </th>
                  ))}
                </tr>
              </thead>
              <tbody>
                {visible.map(f => (
                  <tr key={f.id} className="border-b border-vault-border/50 hover:bg-vault-titanium/30 transition-colors">
                    <td className="px-5 py-4">
                      <span className={`vault-badge-${f.severity}`}>{f.severity.toUpperCase()}</span>
                    </td>
                    <td className="px-5 py-4">
                      <p className="text-vault-text text-sm font-medium leading-snug max-w-md">{f.title}</p>
                      {f.ai_summary && (
                        <p className="text-vault-muted text-xs mt-0.5 line-clamp-1">{f.ai_summary}</p>
                      )}
                    </td>
                    <td className="px-5 py-4 text-vault-muted text-xs whitespace-nowrap">
                      {CATEGORY_LABELS[f.category] ?? f.category}
                    </td>
                    <td className="px-5 py-4">
                      <span className={STATUS_COLORS[f.status] ?? "vault-badge-info"}>
                        {f.status.replace("_", " ")}
                      </span>
                    </td>
                    <td className="px-5 py-4">
                      {f.ai_fix_priority && (
                        <span className={
                          f.ai_fix_priority === "urgent" ? "text-red-400 text-xs font-semibold" :
                          f.ai_fix_priority === "soon" ? "text-amber-400 text-xs font-semibold" :
                          "text-vault-muted text-xs"
                        }>
                          {f.ai_fix_priority}
                        </span>
                      )}
                    </td>
                    <td className="px-5 py-4">
                      <Link
                        href={`/findings/${f.id}`}
                        className="text-vault-sapphireLight text-xs hover:underline whitespace-nowrap"
                      >
                        View →
                      </Link>
                    </td>
                  </tr>
                ))}
              </tbody>
            </table>
          )}
        </div>
      </main>
    </div>
  );
}