import { TriangleAlert } from "lucide-react";
import Link from "next/link";

import {
  Button,
  Card,
  CardContent,
  CardHeader,
  CardTitle,
} from "@/components/shadcn";
import { issuesHref } from "@/lib/issues/scope";
import { VERDICT_TONE, VERDICTS, VerdictTone } from "@/lib/issues/verdicts";
import { cn } from "@/lib/utils";
import { Verdict } from "@/types/issues";

interface ExploitabilityChartProps {
  counts: Record<Verdict, number>;
  issues: number;
  findings: number;
  actionable: number;
  /** Findings folded into not-exploitable issues: a control already covers them. */
  coveredFindings: number;
  /** Overview scope, carried into every drill-down so the counts still match. */
  scope: Record<string, string>;
}

/** The verdicts below the headline, in the order the card lists them. */
const REST: Verdict[] = ["conditional", "unknown", "not_exploitable"];

/** The dot each verdict row wears. */
const TONE_DOT: Record<VerdictTone, string> = {
  [VERDICT_TONE.fail]: "bg-bg-fail",
  [VERDICT_TONE.warning]: "bg-bg-data-medium",
  [VERDICT_TONE.pass]: "bg-bg-pass",
  [VERDICT_TONE.neutral]: "bg-bg-data-muted",
};

/** The share bar runs worst to best; likely is a lighter exploitable. */
const BAR_SEGMENT: Record<Verdict, string> = {
  exploitable: "bg-bg-fail",
  likely: "bg-bg-fail/60",
  conditional: TONE_DOT[VERDICT_TONE.warning],
  unknown: TONE_DOT[VERDICT_TONE.neutral],
  not_exploitable: TONE_DOT[VERDICT_TONE.pass],
};

/**
 * The fold, sized for the ThreatScore row.
 *
 * The headline is exploitable + likely — the issues someone should look at
 * tonight — on a red surface. Everything else is work, not an incident, so it
 * sits as a quiet list underneath. Every number links into the issue list, so
 * nothing here is a dead end.
 */
export const ExploitabilityChart = ({
  counts,
  issues,
  findings,
  actionable,
  coveredFindings,
  scope,
}: ExploitabilityChartProps) => {
  const barTotal = Object.values(counts).reduce((sum, count) => sum + count, 0);

  return (
    <Card
      variant="base"
      className="flex min-h-[372px] w-full min-w-0 flex-col lg:max-w-[312px]"
    >
      <CardHeader className="flex items-baseline justify-between gap-3">
        <CardTitle>Exploitability</CardTitle>
        <span className="text-text-neutral-tertiary text-xs">
          {issues.toLocaleString()} {issues === 1 ? "issue" : "issues"}
        </span>
      </CardHeader>

      <CardContent className="flex flex-1 flex-col gap-3">
        <Link
          href={issuesHref(scope, {
            "filter[verdict__in]": "exploitable,likely",
          })}
          aria-label={`${actionable} exploitable or likely issues`}
          className="border-bg-fail/35 bg-bg-fail/8 hover:bg-bg-fail/15 focus-visible:ring-ring/50 flex items-center gap-3 rounded-lg border px-4 py-3.5 transition-colors focus-visible:ring-2 focus-visible:outline-none"
        >
          <TriangleAlert className="text-bg-fail size-5 shrink-0" />
          <span className="flex min-w-0 flex-1 flex-col gap-0.5">
            <span className="text-text-neutral-primary text-sm font-medium">
              Exploitable or likely
            </span>
            <span className="text-text-neutral-tertiary text-xs">
              {counts.exploitable} exploitable · {counts.likely} likely
            </span>
          </span>
          <span className="text-text-neutral-primary text-[28px] leading-8 font-light tracking-tight tabular-nums">
            {actionable.toLocaleString()}
          </span>
        </Link>

        {/* The ladder's shape: whether this estate is mostly open or mostly
            blocked, sized by share and never by severity. The rows around it
            carry the same links for keyboard and screen-reader users. */}
        {barTotal > 0 && (
          <div
            aria-hidden="true"
            className="bg-bg-neutral-tertiary flex h-2 w-full overflow-hidden rounded-full"
          >
            {(Object.keys(BAR_SEGMENT) as Verdict[])
              .filter((id) => counts[id] > 0)
              .map((id) => (
                <Link
                  key={id}
                  tabIndex={-1}
                  href={issuesHref(scope, { "filter[verdict]": id })}
                  title={`${counts[id]} ${(VERDICTS.find((item) => item.id === id)?.label ?? id).toLowerCase()}`}
                  style={{ width: `${(counts[id] / barTotal) * 100}%` }}
                  className={cn(
                    "h-full transition-opacity hover:opacity-80",
                    BAR_SEGMENT[id],
                  )}
                />
              ))}
          </div>
        )}

        <Card variant="inner" padding="none" className="gap-0 px-4 py-0.5">
          <ul className="divide-border-neutral-secondary flex flex-col divide-y">
            {REST.map((id) => {
              const verdict = VERDICTS.find((item) => item.id === id);
              return (
                <li key={id}>
                  <Link
                    href={issuesHref(scope, { "filter[verdict]": id })}
                    aria-label={`${counts[id]} ${(verdict?.label ?? id).toLowerCase()} ${counts[id] === 1 ? "issue" : "issues"}`}
                    className="text-text-neutral-secondary hover:text-text-neutral-primary focus-visible:ring-ring/50 flex h-10 items-center gap-2.5 rounded-md text-sm transition-colors focus-visible:ring-2 focus-visible:outline-none"
                  >
                    <span
                      aria-hidden
                      className={cn(
                        "size-2 shrink-0 rounded-full",
                        verdict && TONE_DOT[verdict.tone],
                      )}
                    />
                    <span className="flex-1">{verdict?.label ?? id}</span>
                    <span className="text-text-neutral-primary font-semibold tabular-nums">
                      {counts[id].toLocaleString()}
                    </span>
                  </Link>
                </li>
              );
            })}
          </ul>
        </Card>

        {/* The fold. Without the findings count the issue count says nothing
            about how much noise was removed, so the two are always shown
            together. */}
        <p className="border-border-neutral-secondary text-text-neutral-tertiary mt-auto border-t pt-3 text-xs">
          {findings.toLocaleString()} failed findings folded into{" "}
          {issues.toLocaleString()} {issues === 1 ? "issue" : "issues"}
          {coveredFindings > 0 && (
            <>
              {" · "}
              <Button asChild variant="link" size="link-xs">
                <Link
                  href={issuesHref(scope, {
                    "filter[verdict]": "not_exploitable",
                  })}
                >
                  {coveredFindings.toLocaleString()}{" "}
                  {coveredFindings === 1 ? "finding" : "findings"}
                </Link>
              </Button>{" "}
              already covered by a control
            </>
          )}
        </p>
      </CardContent>
    </Card>
  );
};