import Link from "next/link";
import { format } from "date-fns";
import { cn } from "@/lib/utils";
import type { CountdownVerdict, EpisodeCountdown } from "@/lib/dashboard/ops";

/**
 * Are we going to make the date? One card per episode, sorted by how soon.
 *
 * The bar is the episode's shots by where they actually are, and the row under
 * it is the only comparison that matters: shots per day still needed against
 * shots per day the studio has managed this week.
 */

const VERDICT: Record<CountdownVerdict, { rail: string; chip: string; label: string }> = {
  overdue: { rail: "bg-red-500", chip: "text-red-400 bg-red-500/10", label: "Overdue" },
  behind: { rail: "bg-red-500", chip: "text-red-400 bg-red-500/10", label: "Behind" },
  stalled: { rail: "bg-red-500", chip: "text-red-400 bg-red-500/10", label: "Nothing delivered this week" },
  tight: { rail: "bg-amber-500", chip: "text-amber-400 bg-amber-500/10", label: "No slack" },
  ahead: { rail: "bg-green-500", chip: "text-green-400 bg-green-500/10", label: "On track" },
  complete: { rail: "bg-emerald-500", chip: "text-emerald-400 bg-emerald-500/10", label: "All delivered" },
};

/** Two decimals is false precision for a shot count; one is the real resolution. */
const perDay = (n: number) => n.toFixed(1);

export function DeliveryCountdown({ episodes }: { episodes: EpisodeCountdown[] }) {
  if (episodes.length === 0) {
    return (
      <div className="rounded-lg border border-zinc-800 bg-card px-4 py-8 text-center text-sm text-zinc-500">
        No delivery dates set. Add them on a project&apos;s Episodes tab to see the countdown here.
      </div>
    );
  }

  return (
    <div className="grid gap-4 grid-cols-1 md:grid-cols-2 xl:grid-cols-3">
      {episodes.map((ep) => {
        const verdict = VERDICT[ep.verdict];
        const pct = (n: number) => (ep.total === 0 ? 0 : (n / ep.total) * 100);

        return (
          <Link
            key={`${ep.projectId}:${ep.episode ?? ""}`}
            href={`/shot-status?projectId=${ep.projectId}`}
            className="group relative flex flex-col gap-3.5 overflow-hidden rounded-lg border border-zinc-800 bg-card p-4 pl-[18px] transition-colors hover:border-zinc-700 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-amber-500"
          >
            {/* Severity rail — the card itself stays neutral so only the
                episode in trouble pulls the eye. */}
            <span className={cn("absolute inset-y-0 left-0 w-[3px]", verdict.rail)} aria-hidden="true" />

            <div className="flex items-start justify-between gap-3">
              <div className="min-w-0">
                <div className="truncate text-[15px] font-semibold text-white">
                  {ep.projectCode}
                  {ep.episode && <span className="font-normal text-zinc-500"> · ep {ep.episode}</span>}
                </div>
                <div className="mt-0.5 text-xs text-zinc-400">
                  Due {format(ep.dueDate, "EEE d MMM yyyy")}
                </div>
              </div>
              <div className="shrink-0 text-right">
                <b className="block text-3xl font-bold leading-none tabular-nums text-white">
                  {Math.abs(ep.daysLeft)}
                </b>
                <small className="text-[11px] uppercase tracking-wide text-zinc-500">
                  {ep.daysLeft < 0 ? "days over" : "days left"}
                </small>
              </div>
            </div>

            <div>
              <div
                className="flex h-2 overflow-hidden rounded-full bg-zinc-800"
                role="img"
                aria-label={`${ep.delivered} of ${ep.total} shots delivered, ${ep.inQc} through QC, ${ep.inProgress} in progress`}
              >
                <i className="block h-full bg-emerald-500" style={{ width: `${pct(ep.delivered)}%` }} />
                <i className="block h-full bg-amber-500" style={{ width: `${pct(ep.inQc)}%` }} />
                <i className="block h-full bg-blue-500" style={{ width: `${pct(ep.inProgress)}%` }} />
              </div>
              <div className="mt-2 flex flex-wrap gap-x-3 gap-y-1 text-xs text-zinc-400">
                <span className="inline-flex items-center gap-1.5">
                  <i className="h-2 w-2 rounded-sm bg-emerald-500" /> {ep.delivered} delivered
                </span>
                <span className="inline-flex items-center gap-1.5">
                  <i className="h-2 w-2 rounded-sm bg-amber-500" /> {ep.inQc} in QC
                </span>
                <span className="inline-flex items-center gap-1.5">
                  <i className="h-2 w-2 rounded-sm bg-blue-500" /> {ep.inProgress} in progress
                </span>
                <span className="inline-flex items-center gap-1.5">
                  <i className="h-2 w-2 rounded-sm bg-zinc-700" /> {ep.notStarted} not started
                </span>
              </div>
            </div>

            <div className="flex items-center justify-between gap-3 border-t border-zinc-800/60 pt-3">
              <div>
                <div className="text-[11px] text-zinc-500">Needed / day</div>
                <div className="font-mono text-[15px] tabular-nums text-white">
                  {perDay(ep.requiredPerDay)}
                </div>
              </div>
              <div>
                <div className="text-[11px] text-zinc-500">Last 7 days</div>
                <div className="font-mono text-[15px] tabular-nums text-white">
                  {perDay(ep.actualPerDay)}
                </div>
              </div>
              <span className={cn("rounded-full px-2.5 py-1 text-xs font-semibold", verdict.chip)}>
                {ep.verdict === "behind" && ep.daysBehind
                  ? `${ep.daysBehind} day${ep.daysBehind === 1 ? "" : "s"} behind`
                  : ep.verdict === "overdue" && ep.daysBehind
                    ? `${ep.daysBehind} day${ep.daysBehind === 1 ? "" : "s"} over`
                    : verdict.label}
              </span>
            </div>
          </Link>
        );
      })}
    </div>
  );
}