import { useState } from "react";
import { useMutation, useQueryClient } from "@tanstack/react-query";
import type { Bootstrap, Item } from "../../types.js";
import { TYPES } from "../../types.js";
import { fmt, TYPE_GLYPHS } from "../../format.js";
import { api } from "../../api.js";
import { Btn, Field, Input, Select } from "../primitives/index.js";
import { ModalBackdrop, ModalHeader, ModalFooter } from "./ModalChrome.js";

const NEW_BRAND = "__new_brand__";
const NEW_SHOP = "__new_shop__";
const NEW_BIN = "__new_bin__";

export function EditInventoryFlow({
  data,
  item,
  onClose,
}: {
  data: Bootstrap;
  item: Item;
  onClose: () => void;
}) {
  const qc = useQueryClient();

  const isDiscrete = item.kind === "discrete";
  // form.price is total for bulk, per-unit for discrete. Convert at I/O boundaries.
  const initialPrice =
    isDiscrete && item.countOriginal > 0
      ? item.price / item.countOriginal
      : item.price;

  const [form, setForm] = useState({
    brandId: item.brandId ?? NEW_BRAND,
    shopId: item.shopId ?? NEW_SHOP,
    binId: item.binId ?? NEW_BIN,
    weight: item.weight,
    countOriginal: item.countOriginal,
    unitWeight: item.unitWeight,
    price: initialPrice,
    thc: item.thc,
    cbd: item.cbd,
    totalCannabinoids: item.totalCannabinoids,
    purchaseDate: item.purchaseDate,
  });
  const [newBrand, setNewBrand] = useState("");
  const [newShopName, setNewShopName] = useState("");
  const [newShopLocation, setNewShopLocation] = useState("");
  const [newBinName, setNewBinName] = useState("");
  const [newBinCapacity, setNewBinCapacity] = useState(10);
  const [error, setError] = useState<string | null>(null);

  const update = <K extends keyof typeof form>(k: K, v: (typeof form)[K]) =>
    setForm((f) => ({ ...f, [k]: v }));

  const cfg = TYPES.find((t) => t.id === item.type);
  const totalPrice = isDiscrete ? form.price * form.countOriginal : form.price;
  const cpg = !isDiscrete && form.weight > 0 ? form.price / form.weight : 0;

  const save = useMutation({
    mutationFn: async () => {
      let { brandId, shopId, binId } = form;
      if (brandId === NEW_BRAND) {
        if (!newBrand.trim()) throw new Error("New brand name required");
        const b = await api.createBrand(newBrand.trim());
        brandId = b.id;
      }
      if (shopId === NEW_SHOP) {
        if (!newShopName.trim()) throw new Error("New shop name required");
        const s = await api.createShop({
          name: newShopName.trim(),
          location: newShopLocation.trim(),
        });
        shopId = s.id;
      }
      if (binId === NEW_BIN) {
        if (!newBinName.trim()) throw new Error("New bin name required");
        const b = await api.createBin({
          name: newBinName.trim(),
          capacity: newBinCapacity,
        });
        binId = b.id;
      }
      return api.updateInventoryItem(item.id, {
        brandId,
        shopId,
        binId,
        weight: isDiscrete ? undefined : form.weight,
        countOriginal: isDiscrete ? form.countOriginal : undefined,
        unitWeight: isDiscrete ? form.unitWeight : undefined,
        price: totalPrice,
        thc: form.thc,
        cbd: form.cbd,
        totalCannabinoids: form.totalCannabinoids,
        purchaseDate: form.purchaseDate,
      });
    },
    onSuccess: () => {
      qc.invalidateQueries({ queryKey: ["bootstrap"] });
      onClose();
    },
    onError: (e: Error) => setError(e.message),
  });

  const isNewBrand = form.brandId === NEW_BRAND;
  const isNewShop = form.shopId === NEW_SHOP;
  const isNewBin = form.binId === NEW_BIN;

  return (
    <ModalBackdrop onClose={onClose}>
      <div
        style={{
          width: "min(840px, 96vw)",
          margin: "40px 20px",
          background: "var(--bg)",
          border: "1px solid var(--line)",
          borderRadius: "var(--r-lg)",
          boxShadow: "var(--shadow-lg)",
        }}
      >
        <ModalHeader
          title={`Edit ${item.name}`}
          eyebrow={`Inventory · ${item.assetId}`}
          onClose={onClose}
        />

        <div style={{ padding: 32 }}>
          <div
            style={{
              marginBottom: 24,
              padding: "10px 14px",
              background: "var(--bg-2)",
              border: "1px solid var(--line)",
              borderRadius: "var(--r-sm)",
              fontSize: 12,
              color: "var(--ink-3)",
              display: "flex",
              alignItems: "center",
              gap: 8,
            }}
          >
            <span style={{ fontFamily: "var(--serif)", fontSize: 16 }}>
              {TYPE_GLYPHS[item.type]}
            </span>
            <span>
              Editing this physical instance of{" "}
              <strong style={{ color: "var(--ink-2)" }}>{item.name}</strong> ({item.type} ·{" "}
              {item.kind}). To change the product (SKU, name, type), edit the catalog entry.
            </span>
          </div>

          <div className="smallcaps" style={{ color: "var(--ink-3)", marginBottom: 16 }}>
            Source
          </div>
          <div
            style={{
              display: "grid",
              gridTemplateColumns: "repeat(2, 1fr)",
              gap: 16,
              marginBottom: 28,
            }}
          >
            <Field label="Brand">
              <Select value={form.brandId} onChange={(e) => update("brandId", e.target.value)}>
                {data.brands.map((b) => (
                  <option key={b.id} value={b.id}>
                    {b.name}
                  </option>
                ))}
                <option value={NEW_BRAND}>+ Add new brand…</option>
              </Select>
            </Field>
            <Field label="Shop">
              <Select value={form.shopId} onChange={(e) => update("shopId", e.target.value)}>
                {data.shops.map((s) => (
                  <option key={s.id} value={s.id}>
                    {s.name}
                  </option>
                ))}
                <option value={NEW_SHOP}>+ Add new shop…</option>
              </Select>
            </Field>
            {isNewBrand && (
              <Field label="New brand name" span={2}>
                <Input
                  value={newBrand}
                  onChange={(e) => setNewBrand(e.target.value)}
                  placeholder="e.g. Foxglove Farms"
                />
              </Field>
            )}
            {isNewShop && (
              <>
                <Field label="New shop name">
                  <Input
                    value={newShopName}
                    onChange={(e) => setNewShopName(e.target.value)}
                    placeholder="e.g. Greenleaf Co-op"
                  />
                </Field>
                <Field label="Location (optional)">
                  <Input
                    value={newShopLocation}
                    onChange={(e) => setNewShopLocation(e.target.value)}
                    placeholder="e.g. Capitol Hill"
                  />
                </Field>
              </>
            )}
            <Field label="Bin">
              <Select value={form.binId} onChange={(e) => update("binId", e.target.value)}>
                {data.bins.map((b) => (
                  <option key={b.id} value={b.id}>
                    {b.name}
                  </option>
                ))}
                <option value={NEW_BIN}>+ Add new bin…</option>
              </Select>
            </Field>
            {isNewBin && (
              <>
                <Field label="New bin name">
                  <Input
                    value={newBinName}
                    onChange={(e) => setNewBinName(e.target.value)}
                    placeholder="e.g. A1"
                  />
                </Field>
                <Field label="Capacity">
                  <Input
                    type="number"
                    min={1}
                    step={1}
                    value={newBinCapacity}
                    onChange={(e) =>
                      setNewBinCapacity(Math.max(1, Math.floor(+e.target.value || 1)))
                    }
                  />
                </Field>
              </>
            )}
          </div>

          <div className="smallcaps" style={{ color: "var(--ink-3)", marginBottom: 16 }}>
            Acquisition
          </div>
          <div
            style={{
              display: "grid",
              gridTemplateColumns: "repeat(4, 1fr)",
              gap: 16,
              marginBottom: 8,
            }}
          >
            {isDiscrete ? (
              <>
                <Field label={`Quantity (${cfg!.unit})`}>
                  <Input
                    type="number"
                    step="1"
                    value={form.countOriginal}
                    onChange={(e) => update("countOriginal", +e.target.value)}
                  />
                </Field>
                <Field label="Per-unit weight (g)" hint="For grams stats">
                  <Input
                    type="number"
                    step="0.1"
                    value={form.unitWeight}
                    onChange={(e) => update("unitWeight", +e.target.value)}
                  />
                </Field>
              </>
            ) : (
              <Field label={`Size (${cfg?.unit ?? "g"})`} span={2}>
                <Input
                  type="number"
                  step="0.1"
                  value={form.weight}
                  onChange={(e) => update("weight", +e.target.value)}
                />
              </Field>
            )}
            <Field label={isDiscrete ? "Price per unit ($)" : "Price ($)"}>
              <Input
                type="number"
                step="0.01"
                value={form.price}
                onChange={(e) => update("price", +e.target.value)}
              />
            </Field>
            <Field label="Purchase date">
              <Input
                type="date"
                value={form.purchaseDate}
                onChange={(e) => update("purchaseDate", e.target.value)}
              />
            </Field>
          </div>

          {!isDiscrete && cpg > 0 && (
            <div style={{ marginTop: 12, fontSize: 12, color: "var(--ink-3)" }}>
              Cost per {cfg?.unit ?? "g"}:{" "}
              <span className="mono" style={{ color: "var(--ink-2)" }}>
                {fmt.money(cpg)}
              </span>
            </div>
          )}
          {isDiscrete && form.price > 0 && form.countOriginal > 0 && (
            <div style={{ marginTop: 12, fontSize: 12, color: "var(--ink-3)" }}>
              Total:{" "}
              <span className="mono" style={{ color: "var(--ink-2)" }}>
                {fmt.money(totalPrice)}
              </span>
              <span style={{ marginLeft: 6 }}>
                ({form.countOriginal} × {fmt.money(form.price)})
              </span>
            </div>
          )}

          <div
            className="smallcaps"
            style={{ color: "var(--ink-3)", margin: "28px 0 16px" }}
          >
            Cannabinoid profile
          </div>
          <div style={{ display: "grid", gridTemplateColumns: "repeat(3, 1fr)", gap: 16 }}>
            <Field label="THC %">
              <Input
                type="number"
                step="0.1"
                value={form.thc}
                onChange={(e) => update("thc", +e.target.value)}
              />
            </Field>
            <Field label="CBD %">
              <Input
                type="number"
                step="0.1"
                value={form.cbd}
                onChange={(e) => update("cbd", +e.target.value)}
              />
            </Field>
            <Field label="Total cannabinoids %">
              <Input
                type="number"
                step="0.1"
                value={form.totalCannabinoids}
                onChange={(e) => update("totalCannabinoids", +e.target.value)}
              />
            </Field>
          </div>

          {item.audits.length > 0 && (
            <div
              style={{
                marginTop: 18,
                fontSize: 12,
                color: "var(--ink-3)",
                fontStyle: "italic",
              }}
            >
              {item.audits.length} audit{item.audits.length === 1 ? "" : "s"} on file —
              audit history is preserved unchanged. Editing the original size only updates
              the percent-remaining math going forward.
            </div>
          )}

          {error && (
            <div style={{ marginTop: 14, fontSize: 12, color: "var(--terracotta)" }}>{error}</div>
          )}
        </div>

        <ModalFooter>
          <div />
          <div style={{ display: "flex", gap: 8 }}>
            <Btn variant="ghost" onClick={onClose}>
              Cancel
            </Btn>
            <Btn
              variant="primary"
              icon="check"
              disabled={save.isPending}
              onClick={() => save.mutate()}
            >
              {save.isPending ? "Saving…" : "Save changes"}
            </Btn>
          </div>
        </ModalFooter>
      </div>
    </ModalBackdrop>
  );
}