import { Briefcase, ClipboardList, RefreshCw, ShieldCheck, Users } from 'lucide-react'

import { ToolHeader } from '../../components/ToolHeader'
import { Bar, Panel, Stat } from '../../components/ui'
import { num } from '../../lib/format'
import type { RMFunnelStage } from '../../lib/types'
import { recruitBrand } from './brand'
import { useAlerts, useRecommendations, useRecruitDashboard } from './queries'

// Severity maps onto the shared status palette. An unknown severity falls back to muted rather than
// throwing, because the alert_type CHECK can gain values without the UI shipping at the same time.
function severityColor(s: string): string {
  if (s === 'urgent') return 'var(--color-risk)'
  if (s === 'watch') return 'var(--color-warn)'
  return 'var(--color-muted)'
}

// Funnel colors are a fixed progression, deliberately NOT the engine bands. A screen through rate of 50
// percent is not a red candidate: banding a conversion percentage with scoring thresholds would conflate
// two different scales. The backend emits no color for the same reason.
const STAGE_COLOR: Record<string, string> = {
  identified: 'var(--color-blue-soft)',
  screened: 'var(--color-screen)',
  submitted: 'var(--color-recruit)',
  approved: 'var(--color-ok)',
}

function stageColor(s: RMFunnelStage): string {
  return STAGE_COLOR[s.key] ?? 'var(--color-blue)'
}

export function RecruiterDashboard() {
  const { data: d, isLoading, isError, error, refetch, isFetching } = useRecruitDashboard()
  const alerts = useAlerts()
  const recs = useRecommendations()

  if (isLoading) {
    return <Panel className="grid place-items-center py-24 text-muted">Aggregating recruiting operations…</Panel>
  }
  if (isError || !d) {
    return (
      <Panel className="grid place-items-center py-24 text-warn">
        Could not load the recruiting dashboard. {(error as Error)?.message}
      </Panel>
    )
  }

  const benchEmpty = d.headline.identified === 0

  return (
    <div className="space-y-4">
      <ToolHeader name={recruitBrand.name} tagline={recruitBrand.tagline} accent={recruitBrand.accent}>
        <button
          onClick={() => void refetch()}
          disabled={isFetching}
          className="flex items-center gap-2 rounded-lg border border-line/70 px-3 py-2 text-sm font-semibold text-muted hover:text-ink disabled:opacity-50"
        >
          <RefreshCw size={14} className={isFetching ? 'animate-spin' : ''} />
          Refresh
        </button>
      </ToolHeader>

      <p className="text-[11px] font-bold uppercase tracking-wider text-faint">as of {d.as_of}</p>

      <div className="grid grid-cols-2 gap-3 md:grid-cols-3 xl:grid-cols-6">
        <Stat label="Open roles" value={d.headline.active_jobs} icon={<Briefcase size={16} />} accent="var(--color-recruit)" />
        <Stat label="Candidates" value={d.headline.identified} icon={<Users size={16} />} />
        <Stat label="On bench" value={d.headline.on_bench} icon={<ShieldCheck size={16} />} />
        <Stat label="Screened" value={d.headline.screened} />
        <Stat label="Submitted" value={d.headline.submitted} />
        <Stat label="Approved" value={d.headline.approved} accent="var(--color-ok)" />
      </div>

      {/* items-start stops the grid stretching every panel to the tallest column, which is what left
          the short lists sitting in a tall empty box. */}
      <div className="grid grid-cols-1 items-start gap-4 xl:grid-cols-12">
        <Panel title="Pipeline overview" hint="share of the bench" className="xl:col-span-5">
          {benchEmpty ? (
            <p className="py-6 text-center text-sm text-faint">
              No candidates yet. The funnel fills as candidates are added and screened.
            </p>
          ) : (
            <ul className="space-y-3">
              {d.funnel.map((s) => (
                <li key={s.key}>
                  <div className="flex items-baseline justify-between">
                    <span className="text-sm font-semibold">{s.label}</span>
                    <span className="text-sm tabular-nums text-muted">
                      {s.count} <span className="text-faint">({num(s.pct).toFixed(1)}%)</span>
                    </span>
                  </div>
                  <Bar value={num(s.pct)} color={stageColor(s)} />
                </li>
              ))}
            </ul>
          )}
        </Panel>

        <Panel title="Clearance" hint="self reported indicator" className="xl:col-span-4">
          {benchEmpty ? (
            <p className="py-6 text-center text-sm text-faint">No candidates on the bench yet.</p>
          ) : (
            <ul className="space-y-3">
              {d.clearance.map((c) => (
                <li key={c.code}>
                  <div className="flex items-baseline justify-between">
                    <span className="text-sm font-semibold">{c.label}</span>
                    <span className="text-sm tabular-nums text-muted">
                      {c.count} <span className="text-faint">({num(c.pct).toFixed(1)}%)</span>
                    </span>
                  </div>
                  <Bar value={num(c.pct)} color="var(--color-recruit)" />
                </li>
              ))}
            </ul>
          )}
        </Panel>

        <div className="space-y-4 xl:col-span-3">
          <Panel title="Review queue">
            {d.decisions.total === 0 ? (
              <p className="py-6 text-center text-sm text-faint">
                No slate members yet. Generate a slate in slateMATCH.
              </p>
            ) : (
              <ul className="space-y-2.5">
                <li className="flex items-center justify-between">
                  <span className="text-sm" style={{ color: 'var(--color-ok)' }}>Approved</span>
                  <span className="tabular-nums">{d.decisions.approved}</span>
                </li>
                <li className="flex items-center justify-between">
                  <span className="text-sm" style={{ color: 'var(--color-risk)' }}>Rejected</span>
                  <span className="tabular-nums">{d.decisions.rejected}</span>
                </li>
                <li className="flex items-center justify-between">
                  <span className="text-sm" style={{ color: 'var(--color-warn)' }}>Pending</span>
                  <span className="tabular-nums">{d.decisions.pending}</span>
                </li>
                <li className="flex items-center justify-between border-t border-line/50 pt-2.5">
                  <span className="text-[11px] font-bold uppercase tracking-wider text-muted">Approve rate</span>
                  <span className="tabular-nums font-bold">{num(d.decisions.approve_rate).toFixed(1)}%</span>
                </li>
              </ul>
            )}
          </Panel>

          <Panel title="Screening bands">
            {d.band_mix.total === 0 ? (
              <p className="py-6 text-center text-sm text-faint">Nothing screened yet.</p>
            ) : (
              <ul className="space-y-2.5">
                <li className="flex items-center justify-between">
                  <span className="text-sm" style={{ color: 'var(--color-ok)' }}>Proposal ready</span>
                  <span className="tabular-nums">{d.band_mix.green}</span>
                </li>
                <li className="flex items-center justify-between">
                  <span className="text-sm" style={{ color: 'var(--color-warn)' }}>Potential</span>
                  <span className="tabular-nums">{d.band_mix.yellow}</span>
                </li>
                <li className="flex items-center justify-between">
                  <span className="text-sm" style={{ color: 'var(--color-risk)' }}>Recruiting required</span>
                  <span className="tabular-nums">{d.band_mix.red}</span>
                </li>
              </ul>
            )}
          </Panel>
        </div>
      </div>

      <div className="grid grid-cols-1 items-start gap-4 xl:grid-cols-2">
        <Panel title="Open roles by submissions" hint={`${d.top_jobs.length} shown`}>
          {d.top_jobs.length === 0 ? (
            <p className="py-6 text-center text-sm text-faint">No open requirements yet.</p>
          ) : (
            // A list rather than a table. Federal requirement titles and agency names are long enough
            // that a three column table forced the agency to wrap onto three lines and left every row a
            // different height. The agency reads as a subtitle instead, so the title gets the full width.
            <ul className="divide-y divide-line/50">
              {d.top_jobs.map((j) => (
                <li key={j.requirement_id} className="flex items-center justify-between gap-4 py-2.5">
                  <div className="min-w-0">
                    <p className="truncate text-sm font-semibold" title={j.title}>{j.title}</p>
                    <p className="truncate text-[11px] text-faint" title={j.customer_agency || 'n/a'}>
                      {j.customer_agency || 'n/a'}
                    </p>
                  </div>
                  <span className="shrink-0 text-sm tabular-nums text-muted">{j.submitted}</span>
                </li>
              ))}
            </ul>
          )}
        </Panel>

        <Panel title="Recruiter activity" hint="attribution, not a score">
          {d.recruiters.length === 0 ? (
            <p className="py-6 text-center text-sm text-faint">No active users in this organization yet.</p>
          ) : (
            <table className="w-full text-sm">
              <thead>
                <tr className="text-left text-[11px] uppercase tracking-wider text-faint">
                  <th className="pb-2 font-semibold">Recruiter</th>
                  <th className="pb-2 text-right font-semibold">Screened</th>
                  <th className="pb-2 text-right font-semibold">Decided</th>
                  <th className="pb-2 text-right font-semibold">Approved</th>
                </tr>
              </thead>
              <tbody className="divide-y divide-line/50">
                {d.recruiters.map((r) => (
                  <tr key={r.user_id} className="hover:bg-navy-800/40">
                    <td className="py-2.5 font-semibold">{r.full_name}</td>
                    <td className="py-2.5 text-right tabular-nums">{r.screened}</td>
                    <td className="py-2.5 text-right tabular-nums">{r.decided}</td>
                    <td className="py-2.5 text-right tabular-nums">{r.approved}</td>
                  </tr>
                ))}
              </tbody>
            </table>
          )}
        </Panel>
      </div>

      <div className="grid grid-cols-1 items-start gap-4 xl:grid-cols-2">
        <Panel
          title="Alerts"
          hint={alerts.isLoading ? 'loading' : alerts.data ? `${alerts.data.length} unread` : ''}
        >
          {alerts.isError ? (
            <p className="py-6 text-center text-sm text-warn">Alerts are unavailable for your role.</p>
          ) : !alerts.data || alerts.data.length === 0 ? (
            <p className="py-6 text-center text-sm text-faint">
              No open alerts. The watch loop runs daily and posts clearance expiry, recompete and
              coverage findings here.
            </p>
          ) : (
            <ul className="divide-y divide-line/50">
              {alerts.data.slice(0, 6).map((a) => (
                <li key={a.id} className="flex items-start justify-between gap-3 py-2.5">
                  <div className="min-w-0">
                    <p className="truncate text-sm font-semibold" title={a.title}>{a.title}</p>
                    {a.detail ? (
                      <p className="truncate text-[11px] text-faint" title={a.detail}>{a.detail}</p>
                    ) : null}
                  </div>
                  <span
                    className="shrink-0 rounded-full px-2 py-0.5 text-[10px] font-bold uppercase tracking-wide"
                    style={{
                      color: severityColor(a.severity),
                      background: `color-mix(in srgb, ${severityColor(a.severity)} 14%, transparent)`,
                    }}
                  >
                    {a.severity}
                  </span>
                </li>
              ))}
            </ul>
          )}
        </Panel>

        <Panel title="Recommended actions" hint="human decides, never automatic">
          {recs.isError ? (
            <p className="py-6 text-center text-sm text-warn">
              Recommendations are unavailable for your role.
            </p>
          ) : !recs.data || recs.data.recommendations.length === 0 ? (
            <p className="py-6 text-center text-sm text-faint">
              No recommendations yet. These are generated from open requirements and the current bench.
            </p>
          ) : (
            <ul className="divide-y divide-line/50">
              {recs.data.recommendations.map((r) => (
                <li key={r.id} className="py-2.5">
                  <div className="flex items-baseline justify-between gap-3">
                    <span className="text-sm font-semibold capitalize">{r.action}</span>
                    <span className="shrink-0 text-[11px] tabular-nums text-faint">
                      confidence {(num(r.confidence) * 100).toFixed(0)}%
                    </span>
                  </div>
                  <p className="mt-0.5 text-[11px] leading-relaxed text-muted">{r.rationale}</p>
                  {r.rationale_source === 'deterministic' ? (
                    <p className="mt-0.5 text-[10px] uppercase tracking-wide text-faint">
                      deterministic rationale
                    </p>
                  ) : null}
                </li>
              ))}
            </ul>
          )}
        </Panel>
      </div>

      <Panel title="Not tracked yet" hint="named feeds, never invented numbers">
        <ul className="grid grid-cols-1 gap-2 sm:grid-cols-2 xl:grid-cols-3">
          {d.empty_panels.map((p) => (
            <li key={p.key} className="rounded-lg border border-line/60 bg-navy-950/40 p-3">
              <div className="flex items-center gap-2">
                <ClipboardList size={13} className="text-faint" />
                <p className="text-sm font-semibold text-muted">{p.title}</p>
              </div>
              <p className="mt-1 text-[11px] leading-relaxed text-faint">{p.reason}</p>
            </li>
          ))}
        </ul>
      </Panel>
    </div>
  )
}