"use client";

import { EstimateVersionStatus } from "@capakraken/shared";
import { clsx } from "clsx";
import { VersionCompare } from "~/components/estimates/VersionCompare.js";
import type {
  EstimateMetricView,
  EstimateVersionView,
  EstimateWorkspaceView,
} from "~/components/estimates/EstimateWorkspace.types.js";
import { InfoTooltip } from "~/components/ui/InfoTooltip.js";
import { formatDateLong, formatMoney } from "~/lib/format.js";

const VERSION_STYLES: Record<EstimateVersionStatus, string> = {
  WORKING: "bg-sky-100 text-sky-700 dark:bg-sky-900/30 dark:text-sky-300",
  BASELINE: "bg-violet-100 text-violet-700 dark:bg-violet-900/30 dark:text-violet-300",
  SUBMITTED: "bg-amber-100 text-amber-700 dark:bg-amber-900/30 dark:text-amber-300",
  APPROVED: "bg-emerald-100 text-emerald-700 dark:bg-emerald-900/30 dark:text-emerald-300",
  SUPERSEDED: "bg-zinc-200 text-zinc-700 dark:bg-zinc-800 dark:text-zinc-300",
};

function formatMetricValue(metric: EstimateMetricView) {
  if (metric.valueCents != null) {
    return formatMoney(metric.valueCents, metric.currency ?? "EUR");
  }
  if (metric.key === "margin_percent") {
    return `${metric.valueDecimal.toFixed(0)}%`;
  }
  return new Intl.NumberFormat("de-DE", { maximumFractionDigits: 1 }).format(metric.valueDecimal);
}

function EmptyState({ children }: { children: React.ReactNode }) {
  return (
    <div className="rounded-3xl border border-dashed border-gray-200 dark:border-gray-700 bg-white dark:bg-gray-800 px-5 py-10 text-center text-sm text-gray-400">
      {children}
    </div>
  );
}

export interface VersionsTabProps {
  estimate: EstimateWorkspaceView;
  canEdit: boolean;
  hasLinkedProject: boolean;
  onSubmitVersion: (versionId: string) => void;
  onApproveVersion: (versionId: string) => void;
  onCreateRevision: (versionId: string) => void;
  onCreatePlanningHandoff: (versionId: string) => void;
  isSubmitting: boolean;
  isApproving: boolean;
  isCreatingRevision: boolean;
  isCreatingPlanningHandoff: boolean;
}

export function VersionsTab({
  estimate,
  canEdit,
  hasLinkedProject,
  onSubmitVersion,
  onApproveVersion,
  onCreateRevision,
  onCreatePlanningHandoff,
  isSubmitting,
  isApproving,
  isCreatingRevision,
  isCreatingPlanningHandoff,
}: VersionsTabProps) {
  const versions = estimate.versions as EstimateVersionView[];
  const hasWorkingVersion = versions.some(
    (version) => version.status === EstimateVersionStatus.WORKING,
  );

  if (versions.length === 0) {
    return <EmptyState>No versions available for this estimate yet.</EmptyState>;
  }

  return (
    <div className="space-y-3">
      <div className="flex items-center gap-2 text-sm text-gray-500 dark:text-gray-400">
        <span>Versions are immutable snapshots of the estimate for comparison and audit.</span>
        <InfoTooltip content="Each version captures a full copy of scope, assumptions, demand lines, and metrics. WORKING versions can be edited; SUBMITTED and APPROVED versions are locked." />
      </div>
      {versions.map((version) => (
        <div key={version.id} className="rounded-3xl border border-gray-200 dark:border-gray-700 bg-white dark:bg-gray-800 p-5 shadow-sm">
          <div className="flex flex-wrap items-start justify-between gap-4">
            <div>
              <div className="flex items-center gap-2">
                <span className="text-lg font-semibold text-gray-900 dark:text-gray-100">v{version.versionNumber}</span>
                <span className={clsx("rounded-full px-2.5 py-1 text-xs font-medium", VERSION_STYLES[version.status])}>
                  {version.status}
                </span>
              </div>
              <p className="mt-2 text-sm text-gray-600 dark:text-gray-400">{version.label ?? "Unlabeled version"}</p>
              {version.notes && <p className="mt-2 text-sm text-gray-500 dark:text-gray-400">{version.notes}</p>}
            </div>
            <div className="text-right text-sm text-gray-500 dark:text-gray-400">
              <p>Updated {formatDateLong(version.updatedAt)}</p>
              {version.lockedAt && (
                <p className="mt-1">Locked {formatDateLong(version.lockedAt)}</p>
              )}
              <p className="mt-1">{version.demandLines.length} lines</p>
            </div>
          </div>

          {canEdit && (
            <div className="mt-4 flex flex-wrap gap-2">
              {version.status === EstimateVersionStatus.WORKING && (
                <button
                  type="button"
                  onClick={() => onSubmitVersion(version.id)}
                  disabled={isSubmitting || isApproving || isCreatingRevision}
                  className="rounded-2xl border border-amber-200 bg-amber-50 px-3 py-2 text-sm font-semibold text-amber-800 transition hover:border-amber-300 hover:bg-amber-100 disabled:cursor-not-allowed disabled:opacity-60"
                >
                  {isSubmitting ? "Submitting..." : "Submit for review"}
                </button>
              )}

              {version.status === EstimateVersionStatus.SUBMITTED && (
                <button
                  type="button"
                  onClick={() => onApproveVersion(version.id)}
                  disabled={isSubmitting || isApproving || isCreatingRevision}
                  className="rounded-2xl border border-emerald-200 bg-emerald-50 px-3 py-2 text-sm font-semibold text-emerald-800 transition hover:border-emerald-300 hover:bg-emerald-100 disabled:cursor-not-allowed disabled:opacity-60"
                >
                  {isApproving ? "Approving..." : "Approve version"}
                </button>
              )}

              {version.status !== EstimateVersionStatus.WORKING && !hasWorkingVersion && (
                <button
                  type="button"
                  onClick={() => onCreateRevision(version.id)}
                  disabled={isSubmitting || isApproving || isCreatingRevision || isCreatingPlanningHandoff}
                  className="rounded-2xl border border-brand-200 bg-white dark:bg-gray-800 px-3 py-2 text-sm font-semibold text-brand-700 transition hover:border-brand-300 hover:bg-brand-50 disabled:cursor-not-allowed disabled:opacity-60"
                >
                  {isCreatingRevision ? "Creating revision..." : "Create working revision"}
                </button>
              )}

              {version.status === EstimateVersionStatus.APPROVED && (
                <button
                  type="button"
                  onClick={() => onCreatePlanningHandoff(version.id)}
                  disabled={
                    isSubmitting ||
                    isApproving ||
                    isCreatingRevision ||
                    isCreatingPlanningHandoff ||
                    !hasLinkedProject
                  }
                  className="rounded-2xl border border-sky-200 bg-sky-50 px-3 py-2 text-sm font-semibold text-sky-800 transition hover:border-sky-300 hover:bg-sky-100 disabled:cursor-not-allowed disabled:opacity-60"
                >
                  {isCreatingPlanningHandoff
                    ? "Creating planning allocations..."
                    : hasLinkedProject
                      ? "Create planning allocations"
                      : "Link project to hand off"}
                </button>
              )}
            </div>
          )}

          {version.status === EstimateVersionStatus.APPROVED && !hasLinkedProject && (
            <p className="mt-3 text-sm text-amber-700 dark:text-amber-300">
              Link this estimate to a project before handing approved demand into planning.
            </p>
          )}

          {version.metrics.length > 0 && (
            <div className="mt-4 grid gap-3 md:grid-cols-2 xl:grid-cols-5">
              {version.metrics.map((metric) => (
                <div key={metric.id} className="rounded-2xl bg-gray-50 dark:bg-gray-900 px-4 py-3">
                  <p className="text-xs uppercase tracking-wide text-gray-400">{metric.label}</p>
                  <p className="mt-1 text-sm font-semibold text-gray-900 dark:text-gray-100">{formatMetricValue(metric)}</p>
                </div>
              ))}
            </div>
          )}
        </div>
      ))}

      {versions.length >= 2 && <VersionCompare versions={versions} />}
    </div>
  );
}