"use client";

import { useMemo, useState } from "react";
import { useRouter } from "next/navigation";
import { CreditCard, Plus } from "lucide-react";
import { cashBalance, hasOpening, rand, sign } from "@/lib/cash-float";
import { inBounds, presetBounds, saDay, type LogPreset } from "@/lib/oil-log";

export type CashRow = {
  id: string; kind: string; amount: number; at: string; supplier: string; costCode: string;
  asset: string; comment: string; photo: boolean; by: string;
};

const PRESETS: { id: LogPreset; label: string }[] = [
  { id: "today", label: "Today" }, { id: "week", label: "This week" }, { id: "month", label: "This month" },
  { id: "all", label: "Everything" }, { id: "range", label: "Date range" },
];
const when = (s: string) => (s ? new Date(s.replace(" ", "T")).toLocaleString("en-ZA", {
  timeZone: "Africa/Johannesburg", day: "numeric", month: "short", year: "numeric", hour: "2-digit", minute: "2-digit", hourCycle: "h23" }) : "—");
const KIND: Record<string, string> = { opening: "Opening balance", topup: "Top-up", expense: "Slip" };

/**
 * The cash-float card: opening balance, then every slip (photographed in the Plant Clock app)
 * comes off it. Shown as a ledger so any rand can be traced to a slip.
 */
export function CashFloatCard({ rows, costCodes = [], suppliers = [] }: { rows: CashRow[]; costCodes?: string[]; suppliers?: string[] }) {
  const router = useRouter();
  const [preset, setPreset] = useState<LogPreset>("month");
  const [from, setFrom] = useState("");
  const [to, setTo] = useState("");
  const [dialog, setDialog] = useState<"opening" | "topup" | "correct" | null>(null);
  const [manual, setManual] = useState(false);
  const [mSupplier, setMSupplier] = useState("");
  const [mCode, setMCode] = useState("");
  const [mComment, setMComment] = useState("");
  const [mAmount, setMAmount] = useState("");
  const [mDate, setMDate] = useState("");
  const [mPhoto, setMPhoto] = useState<File | null>(null);
  const [amount, setAmount] = useState("");
  const [comment, setComment] = useState("");
  const [busy, setBusy] = useState(false);
  const [error, setError] = useState("");
  const [deleting, setDeleting] = useState<CashRow | null>(null);

  const started = hasOpening(rows);
  const balance = cashBalance(rows);
  const opening = rows.find((r) => r.kind === "opening")?.amount ?? 0;
  const toppedUp = rows.filter((r) => r.kind === "topup").reduce((s, r) => s + r.amount, 0);
  const spent = rows.filter((r) => r.kind === "expense").reduce((s, r) => s + r.amount, 0);

  const shown = useMemo(() => {
    const b = presetBounds(preset, saDay(new Date().toISOString()), from, to);
    return rows.filter((r) => r.kind !== "opening" && inBounds(saDay(r.at), b));
  }, [rows, preset, from, to]);
  const shownSpent = shown.filter((r) => r.kind === "expense").reduce((s, r) => s + r.amount, 0);

  function open(kind: "opening" | "topup" | "correct") {
    setDialog(kind); setError("");
    setAmount(kind === "correct" ? String(opening) : ""); setComment("");
  }
  async function send(url: string, method: string, body: object) {
    setBusy(true); setError("");
    try {
      const res = await fetch(url, { method, headers: { "Content-Type": "application/json" }, body: JSON.stringify(body) });
      const j = await res.json().catch(() => ({}));
      if (!res.ok || j.ok === false || j.error) throw new Error(j.error || "Could not save");
      setDialog(null); setDeleting(null); router.refresh();
    } catch (e: any) { setError(e.message); } finally { setBusy(false); }
  }
  function openManual() {
    setManual(true); setError(""); setMSupplier(""); setMCode(""); setMComment(""); setMAmount(""); setMPhoto(null);
    const d = new Date(); d.setMinutes(d.getMinutes() - d.getTimezoneOffset());
    setMDate(d.toISOString().slice(0, 16));
  }
  async function submitManual(e: React.FormEvent) {
    e.preventDefault();
    setBusy(true); setError("");
    try {
      const body = new FormData();
      body.set("supplier", mSupplier); body.set("cost_code", mCode); body.set("comment", mComment); body.set("amount", mAmount);
      if (mDate) body.set("occurred_on", new Date(mDate).toISOString());
      if (mPhoto) body.set("slip_photo", mPhoto);
      const res = await fetch("/api/cash-float/entries", { method: "POST", body });
      const j = await res.json().catch(() => ({}));
      if (!res.ok || !j.ok) throw new Error(j.error || "Could not save");
      setManual(false); router.refresh();
    } catch (err: any) { setError(err.message); } finally { setBusy(false); }
  }
  function submit(e: React.FormEvent) {
    e.preventDefault();
    if (dialog === "opening") send("/api/clock/cash-float/opening", "POST", { amount });
    else if (dialog === "correct") send("/api/cash-float/opening", "PUT", { amount });
    else if (dialog === "topup") send("/api/cash-float/topup", "POST", { amount, comment });
  }

  const field = "min-h-[44px] rounded-lg border border-gray-200 dark:border-border bg-white dark:bg-surface px-3 text-sm";
  const card = "bg-white dark:bg-surface border border-gray-100 dark:border-border rounded-2xl shadow-sm";

  return (
    <section className="mb-8">
      <div className="flex flex-wrap items-start justify-between gap-3 mb-4">
        <div className="flex items-center gap-3">
          <div className="w-10 h-10 shrink-0 rounded-xl bg-gradient-to-br from-[#00798C]/15 to-[#30638E]/15 grid place-items-center text-[#00798C]"><CreditCard className="w-5 h-5" /></div>
          <div>
            <h1 className="text-2xl font-semibold text-[#003D5B] dark:text-white">Cash Floats</h1>
            <p className="text-xs text-gray-500 dark:text-gray-400">The cash-float card. Slips photographed in the Plant Clock app, or added here by hand, come off the balance.</p>
          </div>
        </div>
        {started && (
          <div className="flex gap-2">
            <button onClick={() => open("correct")} className="min-h-[44px] px-3 rounded-lg border border-gray-200 dark:border-border text-xs font-medium">Correct opening balance</button>
            <button onClick={openManual} className="min-h-[44px] px-4 rounded-lg bg-[#00798C] text-white text-xs font-medium inline-flex items-center gap-1.5"><Plus className="w-4 h-4" />Add entry</button>
            <button onClick={() => open("topup")} className="min-h-[44px] px-4 rounded-lg bg-[#30638E] text-white text-xs font-medium inline-flex items-center gap-1.5"><Plus className="w-4 h-4" />Top up card</button>
          </div>
        )}
      </div>

      {!started ? (
        <div className={`${card} p-6 text-center`}>
          <p className="text-sm font-medium text-[#003D5B] dark:text-white">The card has no opening balance yet</p>
          <p className="text-xs text-gray-500 dark:text-gray-400 mt-1">Enter what is on the card now. Every slip will come off this amount.</p>
          <button onClick={() => open("opening")} className="mt-4 min-h-[44px] px-5 rounded-lg bg-[#30638E] text-white text-sm font-medium">Set opening balance</button>
        </div>
      ) : (
        <>
          <div className="grid grid-cols-2 lg:grid-cols-4 gap-3 mb-4">
            <div className={`${card} p-4`}><p className="text-xs text-gray-500">Balance on card</p><p className={`text-2xl font-semibold tabular-nums mt-1 ${balance < 0 ? "text-[#D1495B]" : "text-[#00798C]"}`}>{rand(balance)}</p></div>
            <div className={`${card} p-4`}><p className="text-xs text-gray-500">Opening balance</p><p className="text-xl font-semibold tabular-nums mt-1">{rand(opening)}</p></div>
            <div className={`${card} p-4`}><p className="text-xs text-gray-500">Topped up</p><p className="text-xl font-semibold tabular-nums mt-1">{rand(toppedUp)}</p></div>
            <div className={`${card} p-4`}><p className="text-xs text-gray-500">Spent on slips</p><p className="text-xl font-semibold tabular-nums mt-1">{rand(spent)}</p></div>
          </div>

          <div className={`${card} p-4 sm:p-5`}>
            <div className="flex flex-col lg:flex-row lg:items-center gap-3 mb-3">
              <div className="hidden lg:flex gap-1.5" role="group" aria-label="Period">
                {PRESETS.map((p) => (
                  <button key={p.id} onClick={() => setPreset(p.id)} aria-pressed={preset === p.id}
                    className={`min-h-[44px] px-4 rounded-lg text-xs font-medium border ${preset === p.id ? "bg-[#30638E] text-white border-[#30638E]" : "border-gray-200 dark:border-border text-gray-600 dark:text-gray-300"}`}>{p.label}</button>
                ))}
              </div>
              <select className={`${field} lg:hidden`} value={preset} onChange={(e) => setPreset(e.target.value as LogPreset)} aria-label="Period">
                {PRESETS.map((p) => <option key={p.id} value={p.id}>{p.label}</option>)}
              </select>
              {preset === "range" && (
                <div className="flex items-center gap-2">
                  <input type="date" className={field} value={from} max={to || undefined} onChange={(e) => setFrom(e.target.value)} aria-label="From" />
                  <span className="text-xs text-gray-500">to</span>
                  <input type="date" className={field} value={to} min={from || undefined} onChange={(e) => setTo(e.target.value)} aria-label="To" />
                </div>
              )}
              <span className="lg:ml-auto text-xs font-medium px-3 py-1.5 rounded-lg bg-[#D1495B]/10 text-[#D1495B]">Spent in this period: {rand(shownSpent)}</span>
            </div>

            {shown.length === 0 ? (
              <p className="text-xs text-gray-500 dark:text-gray-400 py-4">No slips in this period. Office staff photograph slips in the Plant Clock app, on the Slips tab.</p>
            ) : (
              <div className="overflow-x-auto [-webkit-overflow-scrolling:touch]">
                <table className="w-full text-sm min-w-[900px]">
                  <thead>
                    <tr className="text-left text-xs text-gray-500 dark:text-gray-400">
                      <th className="sticky left-0 bg-white dark:bg-surface py-2 pr-3 font-medium">When</th>
                      <th className="py-2 pr-3 font-medium">Type</th>
                      <th className="py-2 pr-3 font-medium">Supplier</th>
                      <th className="py-2 pr-3 font-medium">Cost code</th>
                      <th className="py-2 pr-3 font-medium">Comments</th>
                      <th className="py-2 pr-3 font-medium text-right">Amount</th>
                      <th className="py-2 pr-3 font-medium">By</th>
                      <th className="py-2 font-medium">Slip</th>
                    </tr>
                  </thead>
                  <tbody>
                    {shown.map((r) => (
                      <tr key={r.id} className="border-t border-gray-100 dark:border-border align-top">
                        <td className="sticky left-0 bg-white dark:bg-surface py-2 pr-3 whitespace-nowrap tabular-nums">{when(r.at)}</td>
                        <td className="py-2 pr-3 whitespace-nowrap">{KIND[r.kind] ?? r.kind}</td>
                        <td className="py-2 pr-3">{r.supplier || "—"}</td>
                        <td className="py-2 pr-3 font-mono">{r.costCode || "—"}{r.asset && <span className="ml-1 text-[10px] text-[#00798C]" title="Linked to a vehicle">●</span>}</td>
                        <td className="py-2 pr-3 min-w-[200px] whitespace-pre-wrap break-words">{r.comment || "—"}</td>
                        <td className={`py-2 pr-3 text-right tabular-nums whitespace-nowrap ${sign(r.kind) < 0 ? "text-[#D1495B]" : "text-[#00798C]"}`}>{sign(r.kind) < 0 ? "−" : "+"}{rand(r.amount)}</td>
                        <td className="py-2 pr-3">{r.by || "—"}</td>
                        <td className="py-2 whitespace-nowrap">
                          <div className="flex items-center gap-1">
                            {r.photo && <a href={`/api/cash-float/entries/${r.id}/photo`} target="_blank" rel="noopener noreferrer" className="inline-flex min-h-[44px] items-center px-2 text-[#30638E] underline">View slip</a>}
                            <button onClick={() => { setError(""); setDeleting(r); }} className="min-h-[44px] px-2 text-xs text-[#D1495B] hover:bg-[#D1495B]/10 rounded-lg">Delete</button>
                          </div>
                        </td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>
            )}
          </div>
        </>
      )}

      {manual && (
        <div className="fixed inset-0 z-50 grid place-items-center bg-black/50 p-4" onClick={() => !busy && setManual(false)}>
          <form onClick={(e) => e.stopPropagation()} onSubmit={submitManual} role="dialog" aria-modal="true" aria-label="Add entry"
            className="w-full max-w-md max-h-[92svh] overflow-y-auto rounded-2xl bg-white dark:bg-surface p-5 shadow-xl">
            <h3 className="text-base font-semibold text-[#003D5B] dark:text-white">Add an entry by hand</h3>
            <p className="text-xs text-gray-500 dark:text-gray-400 mt-1">For a slip that was not photographed. It comes off the card balance like any other slip.</p>
            <label htmlFor="m-supplier" className="block text-sm font-medium mt-4">Supplier</label>
            <input id="m-supplier" autoFocus list="cf-suppliers" value={mSupplier} onChange={(e) => setMSupplier(e.target.value)} maxLength={200} className={`${field} w-full mt-1`} />
            <datalist id="cf-suppliers">{suppliers.map((s) => <option key={s} value={s} />)}</datalist>
            <label htmlFor="m-amount" className="block text-sm font-medium mt-3">Amount (R)</label>
            <input id="m-amount" type="text" inputMode="decimal" value={mAmount} onChange={(e) => setMAmount(e.target.value)} className={`${field} w-full mt-1 text-lg tabular-nums`} placeholder="0.00" />
            <label htmlFor="m-date" className="block text-sm font-medium mt-3">Date and time of the slip</label>
            <input id="m-date" type="datetime-local" value={mDate} onChange={(e) => setMDate(e.target.value)} className={`${field} w-full mt-1`} />
            <label htmlFor="m-code" className="block text-sm font-medium mt-3">Cost code <span className="font-normal text-gray-500">(optional)</span></label>
            <input id="m-code" list="cf-codes" value={mCode} onChange={(e) => setMCode(e.target.value)} maxLength={100} className={`${field} w-full mt-1`} placeholder="e.g. TLB04" />
            <datalist id="cf-codes">{costCodes.map((c) => <option key={c} value={c} />)}</datalist>
            <label htmlFor="m-comment" className="block text-sm font-medium mt-3">Comments <span className="font-normal text-gray-500">(optional)</span></label>
            <textarea id="m-comment" value={mComment} onChange={(e) => setMComment(e.target.value)} maxLength={1000} className="mt-1 w-full min-h-[70px] rounded-lg border border-gray-200 dark:border-border bg-white dark:bg-surface p-2 text-sm" />
            <label htmlFor="m-photo" className="block text-sm font-medium mt-3">Photo of the slip <span className="font-normal text-gray-500">(optional)</span></label>
            <input id="m-photo" type="file" accept="image/*" onChange={(e) => setMPhoto(e.target.files?.[0] ?? null)} className="mt-1 w-full text-sm" />
            {error && <p role="alert" className="text-xs text-[#D1495B] mt-3">{error}</p>}
            <div className="flex justify-end gap-2 mt-5">
              <button type="button" disabled={busy} onClick={() => setManual(false)} className="min-h-[44px] px-4 rounded-lg text-sm border border-gray-200 dark:border-border">Cancel</button>
              <button type="submit" disabled={busy || !mSupplier.trim() || !mAmount.trim()} className="min-h-[44px] px-5 rounded-lg text-sm font-medium text-white bg-[#00798C] disabled:opacity-60">{busy ? "Saving…" : "Add entry"}</button>
            </div>
          </form>
        </div>
      )}

      {dialog && (
        <div className="fixed inset-0 z-50 grid place-items-center bg-black/50 p-4" onClick={() => !busy && setDialog(null)}>
          <form onClick={(e) => e.stopPropagation()} onSubmit={submit} role="dialog" aria-modal="true" className="w-full max-w-sm rounded-2xl bg-white dark:bg-surface p-5 shadow-xl">
            <h3 className="text-base font-semibold text-[#003D5B] dark:text-white">
              {dialog === "opening" ? "Set the opening balance" : dialog === "correct" ? "Correct the opening balance" : "Top up the card"}
            </h3>
            <p className="text-xs text-gray-500 dark:text-gray-400 mt-1">
              {dialog === "topup" ? "Money loaded onto the card. It is added to the balance." : "The balance on the card when tracking started. Slips and top-ups are not changed."}
            </p>
            <label htmlFor="cf-amount" className="block text-sm font-medium mt-4">Amount (R)</label>
            <input id="cf-amount" autoFocus type="text" inputMode="decimal" value={amount} onChange={(e) => setAmount(e.target.value)} className={`${field} w-full text-lg tabular-nums mt-1`} placeholder="0.00" />
            {dialog === "topup" && (<>
              <label htmlFor="cf-comment" className="block text-sm font-medium mt-3">Note <span className="font-normal text-gray-500">(optional)</span></label>
              <input id="cf-comment" value={comment} onChange={(e) => setComment(e.target.value)} className={`${field} w-full mt-1`} maxLength={1000} />
            </>)}
            {error && <p role="alert" className="text-xs text-[#D1495B] mt-3">{error}</p>}
            <div className="flex justify-end gap-2 mt-5">
              <button type="button" disabled={busy} onClick={() => setDialog(null)} className="min-h-[44px] px-4 rounded-lg text-sm border border-gray-200 dark:border-border">Cancel</button>
              <button type="submit" disabled={busy || !amount.trim()} className="min-h-[44px] px-5 rounded-lg text-sm font-medium text-white bg-[#30638E] disabled:opacity-60">{busy ? "Saving…" : "Save"}</button>
            </div>
          </form>
        </div>
      )}

      {deleting && (
        <div className="fixed inset-0 z-50 grid place-items-center bg-black/50 p-4" onClick={() => !busy && setDeleting(null)}>
          <div onClick={(e) => e.stopPropagation()} role="alertdialog" aria-modal="true" className="w-full max-w-sm rounded-2xl bg-white dark:bg-surface p-5 shadow-xl">
            <h3 className="text-base font-semibold text-[#003D5B] dark:text-white">Delete this entry?</h3>
            <p className="text-sm text-gray-600 dark:text-gray-300 mt-2">{KIND[deleting.kind]} · {deleting.supplier || "—"} · {rand(deleting.amount)}</p>
            <p className="text-xs text-gray-500 dark:text-gray-400 mt-2">The balance is recalculated without it. The slip photo is deleted too. This cannot be undone.</p>
            {error && <p role="alert" className="text-xs text-[#D1495B] mt-3">{error}</p>}
            <div className="flex justify-end gap-2 mt-5">
              <button disabled={busy} onClick={() => setDeleting(null)} className="min-h-[44px] px-4 rounded-lg text-sm border border-gray-200 dark:border-border">Cancel</button>
              <button disabled={busy} onClick={() => send(`/api/cash-float/entries/${deleting.id}`, "DELETE", {})} className="min-h-[44px] px-5 rounded-lg text-sm font-medium text-white bg-[#D1495B] disabled:opacity-60">{busy ? "Deleting…" : "Delete"}</button>
            </div>
          </div>
        </div>
      )}
    </section>
  );
}