"use client";

import { useState } from "react";
import { useRouter } from "next/navigation";
import { formatDate } from "~/lib/format.js";
import { InfoTooltip } from "~/components/ui/InfoTooltip.js";
import { FillOpenDemandModal } from "~/components/allocations/FillOpenDemandModal.js";
import { AllocationModal } from "~/components/allocations/AllocationModal.js";
import type { AllocationWithDetails } from "@planarchy/shared";
import type { OpenDemandAssignment } from "~/components/timeline/TimelineProjectPanel.js";
import { usePermissions } from "~/hooks/usePermissions.js";
import { trpc } from "~/lib/trpc/client.js";
import { ALLOCATION_STATUS_BADGE as ALLOC_STATUS_COLORS } from "~/lib/status-styles.js";

interface DemandRow {
  id: string;
  projectId: string;
  role: string | null;
  roleId: string | null;
  roleEntity?: { id: string; name: string; color: string | null } | null;
  startDate: Date | string;
  endDate: Date | string;
  hoursPerDay: number;
  headcount: number;
  budgetCents?: number;
  requestedHeadcount: number;
  unfilledHeadcount: number;
  status: string;
  project?: { id: string; name: string; shortCode: string };
  assignments?: Array<{ dailyCostCents: number; startDate: Date | string; endDate: Date | string; status: string }>;
}

interface ProjectDemandsTableProps {
  demands: DemandRow[];
  project: { id: string; name: string; shortCode: string };
}

export function ProjectDemandsTable({ demands, project }: ProjectDemandsTableProps) {
  const [fillTarget, setFillTarget] = useState<OpenDemandAssignment | null>(null);
  const [editTarget, setEditTarget] = useState<AllocationWithDetails | null>(null);
  const { canEdit } = usePermissions();
  const router = useRouter();
  const utils = trpc.useUtils();

  function handleMutationSuccess() {
    // Invalidate budget status so BudgetStatusCard refetches
    void utils.timeline.getBudgetStatus.invalidate();
    void utils.allocation.listView.invalidate();
    router.refresh();
  }

  const activeDemands = demands.filter((d) => d.status !== "CANCELLED" && d.status !== "COMPLETED");
  const allDemands = demands;

  return (
    <>
      <div className="bg-white dark:bg-gray-900 rounded-xl border border-gray-200 dark:border-gray-700 overflow-hidden">
        <div className="px-6 py-4 border-b border-gray-200 dark:border-gray-700 flex items-center justify-between">
          <h2 className="text-sm font-semibold text-gray-700 dark:text-gray-300 uppercase tracking-wider">
            Open Demands ({allDemands.length})
          </h2>
          {activeDemands.length > 0 && (
            <span className="text-xs text-amber-600 dark:text-amber-400">
              {activeDemands.reduce((sum, d) => sum + d.unfilledHeadcount, 0)} seats unfilled
            </span>
          )}
        </div>
        <table className="w-full">
          <thead className="bg-gray-50 dark:bg-gray-800/50 border-b border-gray-200 dark:border-gray-700">
            <tr>
              <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 dark:text-gray-400 uppercase tracking-wider">
                Role
              </th>
              <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 dark:text-gray-400 uppercase tracking-wider">
                Period
              </th>
              <th className="px-4 py-3 text-right text-xs font-medium text-gray-500 dark:text-gray-400 uppercase tracking-wider">
                <span className="inline-flex items-center justify-end gap-0.5">
                  Headcount <InfoTooltip content="Requested / Unfilled seats for this demand." />
                </span>
              </th>
              <th className="px-4 py-3 text-right text-xs font-medium text-gray-500 dark:text-gray-400 uppercase tracking-wider">
                Hours/Day
              </th>
              <th className="px-4 py-3 text-right text-xs font-medium text-gray-500 dark:text-gray-400 uppercase tracking-wider">
                <span className="inline-flex items-center justify-end gap-0.5">
                  Budget <InfoTooltip content="Allocated role budget vs. booked cost from assignments." />
                </span>
              </th>
              <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 dark:text-gray-400 uppercase tracking-wider">
                Status
              </th>
              {canEdit && (
                <th className="px-4 py-3 text-right text-xs font-medium text-gray-500 dark:text-gray-400 uppercase tracking-wider">
                  Actions
                </th>
              )}
            </tr>
          </thead>
          <tbody className="divide-y divide-gray-100 dark:divide-gray-800">
            {allDemands.map((demand) => {
              const isFillable = demand.status !== "CANCELLED" && demand.status !== "COMPLETED" && demand.unfilledHeadcount > 0;
              return (
                <tr key={demand.id} className="hover:bg-gray-50 dark:hover:bg-gray-800/30 transition-colors">
                  <td className="px-4 py-3 text-sm text-gray-900 dark:text-gray-100">
                    {demand.roleEntity?.name ?? demand.role ?? "Unassigned"}
                  </td>
                  <td className="px-4 py-3 text-xs text-gray-500 dark:text-gray-400">
                    {formatDate(demand.startDate)} → {formatDate(demand.endDate)}
                  </td>
                  <td className="px-4 py-3 text-sm text-right text-gray-900 dark:text-gray-100">
                    <span className="font-medium">{demand.unfilledHeadcount}</span>
                    <span className="text-gray-400"> / {demand.requestedHeadcount}</span>
                  </td>
                  <td className="px-4 py-3 text-sm text-right text-gray-900 dark:text-gray-100">{demand.hoursPerDay}h</td>
                  <td className="px-4 py-3 text-right text-sm">
                    {demand.budgetCents && demand.budgetCents > 0 ? (() => {
                      // Calculate booked cost from assignments
                      const bookedCents = (demand.assignments ?? [])
                        .filter((a) => a.status !== "CANCELLED")
                        .reduce((sum, a) => {
                          const s = new Date(a.startDate);
                          const e = new Date(a.endDate);
                          let days = 0;
                          const cur = new Date(s);
                          while (cur <= e) { if (cur.getDay() !== 0 && cur.getDay() !== 6) days++; cur.setDate(cur.getDate() + 1); }
                          return sum + a.dailyCostCents * days;
                        }, 0);
                      const remainCents = demand.budgetCents! - bookedCents;
                      return (
                        <div>
                          <div className="text-gray-900 dark:text-gray-100">
                            {(demand.budgetCents! / 100).toLocaleString("de-DE", { minimumFractionDigits: 2 })} EUR
                          </div>
                          <div className={`text-xs ${remainCents < 0 ? "text-red-500" : "text-gray-400"}`}>
                            {bookedCents > 0 ? `${(bookedCents / 100).toLocaleString("de-DE", { minimumFractionDigits: 2 })} booked` : ""}
                            {remainCents < 0 ? ` (${(Math.abs(remainCents) / 100).toLocaleString("de-DE", { minimumFractionDigits: 2 })} over)` : ""}
                          </div>
                        </div>
                      );
                    })() : (
                      <span className="text-gray-400 text-xs">—</span>
                    )}
                  </td>
                  <td className="px-4 py-3">
                    <span className={`inline-block px-2 py-0.5 text-xs rounded-full ${ALLOC_STATUS_COLORS[demand.status] ?? "bg-gray-100 text-gray-600"}`}>
                      {demand.status}
                    </span>
                  </td>
                  {canEdit && (
                    <td className="px-4 py-3 text-right">
                      <div className="flex items-center justify-end gap-2">
                        <button
                          type="button"
                          onClick={() => setEditTarget(demand as unknown as AllocationWithDetails)}
                          className="text-xs font-medium text-blue-600 hover:text-blue-800 dark:text-blue-400 dark:hover:text-blue-200"
                        >
                          Edit
                        </button>
                        {isFillable && (
                          <button
                            type="button"
                            onClick={() => setFillTarget({
                              id: demand.id,
                              projectId: demand.projectId,
                              roleId: demand.roleId,
                              role: demand.role,
                              headcount: demand.headcount,
                              ...(demand.budgetCents ? { budgetCents: demand.budgetCents } : {}),
                              startDate: new Date(demand.startDate),
                              endDate: new Date(demand.endDate),
                              hoursPerDay: demand.hoursPerDay,
                              roleEntity: demand.roleEntity ?? null,
                              project,
                            })}
                            className="inline-flex items-center gap-1 text-xs font-medium text-brand-600 hover:text-brand-800 dark:text-brand-400 dark:hover:text-brand-200"
                          >
                            <svg className="h-3.5 w-3.5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M18 9v3m0 0v3m0-3h3m-3 0h-3m-2-5a4 4 0 11-8 0 4 4 0 018 0zM3 20a6 6 0 0112 0v1H3v-1z" />
                            </svg>
                            Assign
                          </button>
                        )}
                      </div>
                    </td>
                  )}
                </tr>
              );
            })}
          </tbody>
        </table>
        {allDemands.length === 0 && (
          <div className="text-center py-12 text-gray-500 dark:text-gray-400 text-sm">No open demands for this project.</div>
        )}
      </div>

      {fillTarget && (
        <FillOpenDemandModal
          allocation={fillTarget as never}
          onClose={() => { setFillTarget(null); handleMutationSuccess(); }}
          onSuccess={() => { setFillTarget(null); handleMutationSuccess(); }}
        />
      )}

      {editTarget && (
        <AllocationModal
          allocation={editTarget}
          onClose={() => { setEditTarget(null); handleMutationSuccess(); }}
          onSuccess={() => { setEditTarget(null); handleMutationSuccess(); }}
        />
      )}
    </>
  );
}
