"use client";

import { useEffect, useRef, useState, useCallback } from "react";
import {
  ChevronLeft, ChevronRight, Copy, Plus, Check, Loader2,
  Trash2, AlertCircle, ChevronDown, ChevronUp,
} from "lucide-react";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { Textarea } from "@/components/ui/textarea";
import { cn } from "@/lib/utils";
import { TakeImageGallery } from "./TakeImageGallery";
import { PreviousTakePanel } from "./PreviousTakePanel";
import type { TakeQuality } from "@prisma/client";

// ─── Types ────────────────────────────────────────────────────────────────────

export interface TakeAttachmentData {
  id: string;
  fileUrl: string;
  fileName: string;
  fileType: string;
  category: string;
  caption: string | null;
  sortOrder: number;
}

export interface FullTake {
  id: string;
  setupId: string;
  takeNumber: number;
  scene: string | null;
  shotLabel: string | null;
  unitLabel: string | null;
  cameraLetter: string | null;
  clipName: string | null;
  roll: string | null;
  cameraModel: string | null;
  resolution: string | null;
  codec: string | null;
  fps: number | null;
  shutter: string | null;
  iso: number | null;
  whiteBalance: number | null;
  colourSpace: string | null;
  lensSet: string | null;
  lens: string | null;
  tStop: string | null;
  filters: string | null;
  isAnamorphic: boolean;
  hasHdri: boolean;
  hasChromeBall: boolean;
  hasGreyBall: boolean;
  hasMacbeth: boolean;
  hasCleanPlate: boolean;
  hasSurvey: boolean;
  hasLidar: boolean;
  hasWitnessCamera: boolean;
  hasLensGrid: boolean;
  hasTexturePhotos: boolean;
  hasPhotogrammetry: boolean;
  weather: string | null;
  sunDirection: string | null;
  artificialLights: string | null;
  supervisorNotes: string | null;
  continuityNotes: string | null;
  vfxRequirements: string | null;
  quality: TakeQuality;
  attachments: TakeAttachmentData[];
  setup: {
    takes: { id: string; takeNumber: number }[];
    shootDay: { id: string; date: string; unit: string; label: string | null; projectId: string };
  };
}

// ─── Quality config ───────────────────────────────────────────────────────────

const QUALITIES: { value: TakeQuality; label: string; color: string; active: string }[] = [
  { value: "FALSE_START", label: "False Start", color: "border-zinc-700 text-zinc-500", active: "bg-zinc-700 text-zinc-200 border-zinc-600" },
  { value: "NO_GOOD",     label: "No Good",     color: "border-red-900/60 text-red-500",   active: "bg-red-900/60 text-red-200 border-red-700" },
  { value: "PRINT",       label: "Print",       color: "border-amber-800/60 text-amber-500", active: "bg-amber-800/60 text-amber-200 border-amber-600" },
  { value: "GOOD",        label: "Good",        color: "border-blue-800/60 text-blue-400",  active: "bg-blue-900/60 text-blue-200 border-blue-600" },
  { value: "HERO",        label: "Hero ★",      color: "border-green-800/60 text-green-500", active: "bg-green-900/60 text-green-200 border-green-600" },
];

const TRACKING_ITEMS: { key: keyof FullTake; label: string }[] = [
  { key: "hasHdri",           label: "HDRI" },
  { key: "hasChromeBall",     label: "Chrome Ball" },
  { key: "hasGreyBall",       label: "Grey Ball" },
  { key: "hasMacbeth",        label: "Macbeth" },
  { key: "hasCleanPlate",     label: "Clean Plate" },
  { key: "hasSurvey",         label: "Survey" },
  { key: "hasLidar",          label: "LiDAR" },
  { key: "hasWitnessCamera",  label: "Witness Cam" },
  { key: "hasLensGrid",       label: "Lens Grid" },
  { key: "hasTexturePhotos",  label: "Texture Photos" },
  { key: "hasPhotogrammetry", label: "Photogrammetry" },
];

// ─── Autosave hook ────────────────────────────────────────────────────────────

type SaveStatus = "clean" | "dirty" | "saving" | "saved" | "error";

function useAutosave(takeId: string) {
  const [status, setStatus] = useState<SaveStatus>("clean");
  const timerRef = useRef<ReturnType<typeof setTimeout> | null>(null);
  const pendingRef = useRef<Record<string, unknown>>({});

  const flush = useCallback(async () => {
    if (Object.keys(pendingRef.current).length === 0) return;
    const patch = { ...pendingRef.current };
    pendingRef.current = {};
    setStatus("saving");
    try {
      const res = await fetch(`/api/shoot-log/takes/${takeId}`, {
        method: "PATCH",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify(patch),
      });
      if (!res.ok) throw new Error("save failed");
      setStatus("saved");
      setTimeout(() => setStatus("clean"), 2000);
    } catch {
      setStatus("error");
    }
  }, [takeId]);

  const queue = useCallback(
    (patch: Record<string, unknown>) => {
      pendingRef.current = { ...pendingRef.current, ...patch };
      setStatus("dirty");
      if (timerRef.current) clearTimeout(timerRef.current);
      timerRef.current = setTimeout(flush, 800);
    },
    [flush]
  );

  // Flush immediately when takeId changes
  useEffect(() => {
    return () => {
      if (timerRef.current) clearTimeout(timerRef.current);
    };
  }, [takeId]);

  return { status, queue, flush };
}

// ─── Field components ─────────────────────────────────────────────────────────

function Field({
  label,
  children,
  className,
}: {
  label: string;
  children: React.ReactNode;
  className?: string;
}) {
  return (
    <div className={cn("flex flex-col gap-1", className)}>
      <label className="text-[10px] font-semibold uppercase tracking-wider text-zinc-500">
        {label}
      </label>
      {children}
    </div>
  );
}

function TF({
  value,
  onChange,
  placeholder,
  type = "text",
  className,
}: {
  value: string;
  onChange: (v: string) => void;
  placeholder?: string;
  type?: string;
  className?: string;
}) {
  return (
    <Input
      type={type}
      value={value}
      onChange={(e) => onChange(e.target.value)}
      placeholder={placeholder}
      className={cn("h-9 bg-zinc-900 border-zinc-700 text-sm", className)}
    />
  );
}

function SectionHeader({ title }: { title: string }) {
  return (
    <div className="flex items-center gap-3 py-1">
      <span className="text-[10px] font-bold uppercase tracking-widest text-zinc-500">{title}</span>
      <div className="flex-1 h-px bg-zinc-800" />
    </div>
  );
}

// ─── Main component ───────────────────────────────────────────────────────────

interface Props {
  take: FullTake;
  previousTake: FullTake | null;
  onPrev: (() => void) | null;
  onNext: (() => void) | null;
  onDuplicate: () => void;
  onNewTake: () => void;
  onDelete: () => void;
  onAttachmentsChange: () => void;
}

export function TakeEditorPanel({
  take,
  previousTake,
  onPrev,
  onNext,
  onDuplicate,
  onNewTake,
  onDelete,
  onAttachmentsChange,
}: Props) {
  const { status, queue } = useAutosave(take.id);

  // Local field state — initialised from take prop, synced when take.id changes
  const [fields, setFields] = useState<FullTake>(take);
  const prevIdRef = useRef(take.id);

  useEffect(() => {
    if (take.id !== prevIdRef.current) {
      setFields(take);
      prevIdRef.current = take.id;
    }
  }, [take]);

  const [showPrevPanel, setShowPrevPanel] = useState(false);

  function set<K extends keyof FullTake>(key: K, value: FullTake[K]) {
    setFields((f) => ({ ...f, [key]: value }));
    queue({ [key]: value });
  }

  const str = (v: string | null) => v ?? "";
  const num = (v: number | null) => (v !== null && v !== undefined ? String(v) : "");

  // Keyboard shortcuts
  useEffect(() => {
    function handleKey(e: KeyboardEvent) {
      if (e.target instanceof HTMLInputElement || e.target instanceof HTMLTextAreaElement) return;
      if (e.key === "ArrowLeft" && onPrev) onPrev();
      if (e.key === "ArrowRight" && onNext) onNext();
      if (e.key === "d" && !e.metaKey && !e.ctrlKey) onDuplicate();
      if (e.key === "n" && !e.metaKey && !e.ctrlKey) onNewTake();
    }
    window.addEventListener("keydown", handleKey);
    return () => window.removeEventListener("keydown", handleKey);
  }, [onPrev, onNext, onDuplicate, onNewTake]);

  return (
    <div className="flex flex-col h-full overflow-hidden">
      {/* ── Nav bar ── */}
      <div className="flex items-center gap-2 px-4 py-3 border-b border-zinc-800 shrink-0 flex-wrap">
        <div className="flex items-center gap-1">
          <Button size="icon-sm" variant="ghost" disabled={!onPrev} onClick={onPrev ?? undefined} title="Previous take (←)">
            <ChevronLeft className="h-4 w-4" />
          </Button>
          <Button size="icon-sm" variant="ghost" disabled={!onNext} onClick={onNext ?? undefined} title="Next take (→)">
            <ChevronRight className="h-4 w-4" />
          </Button>
        </div>

        <div className="flex-1 min-w-0">
          <h2 className="text-sm font-semibold text-white">
            Setup {take.setup.shootDay.unit} · Take {take.takeNumber}
          </h2>
          <p className="text-[11px] text-zinc-500">
            {new Date(take.setup.shootDay.date).toLocaleDateString("en-GB", {
              weekday: "short", day: "numeric", month: "short", year: "numeric",
            })}
            {take.setup.shootDay.label ? ` · ${take.setup.shootDay.label}` : ""}
          </p>
        </div>

        {/* Save status */}
        <div className="shrink-0">
          {status === "saving" && <Loader2 className="h-4 w-4 animate-spin text-zinc-500" />}
          {status === "saved" && <Check className="h-4 w-4 text-green-500" />}
          {status === "dirty" && <span className="h-2 w-2 rounded-full bg-amber-400 inline-block" />}
          {status === "error" && <AlertCircle className="h-4 w-4 text-red-500" />}
        </div>

        <div className="flex items-center gap-1 shrink-0">
          <Button size="sm" variant="secondary" onClick={onDuplicate} title="Duplicate take (D)">
            <Copy className="h-3.5 w-3.5" />
            Dup
          </Button>
          <Button size="sm" variant="secondary" onClick={onNewTake} title="New take (N)">
            <Plus className="h-3.5 w-3.5" />
            Take
          </Button>
          <Button size="icon-sm" variant="destructive" onClick={onDelete} title="Delete take">
            <Trash2 className="h-3.5 w-3.5" />
          </Button>
        </div>
      </div>

      {/* ── Quality bar ── */}
      <div className="flex items-center gap-2 px-4 py-3 border-b border-zinc-800 shrink-0 flex-wrap">
        {QUALITIES.map((q) => (
          <button
            key={q.value}
            onClick={() => set("quality", q.value)}
            className={cn(
              "px-4 py-2 rounded-lg border text-xs font-semibold transition-all min-h-[36px]",
              fields.quality === q.value ? q.active : q.color
            )}
          >
            {q.label}
          </button>
        ))}
      </div>

      {/* ── Scrollable form ── */}
      <div className="flex-1 overflow-y-auto">
        <div className="px-4 py-4 space-y-5 max-w-4xl">

          {/* General */}
          <SectionHeader title="General" />
          <div className="grid grid-cols-2 sm:grid-cols-3 lg:grid-cols-4 gap-3">
            <Field label="Scene">
              <TF value={str(fields.scene)} onChange={(v) => set("scene", v || null)} placeholder="e.g. 12" />
            </Field>
            <Field label="Shot">
              <TF value={str(fields.shotLabel)} onChange={(v) => set("shotLabel", v || null)} placeholder="e.g. 12A" />
            </Field>
            <Field label="Unit">
              <TF value={str(fields.unitLabel)} onChange={(v) => set("unitLabel", v || null)} placeholder="e.g. A" />
            </Field>
            <Field label="Take #">
              <TF value={String(fields.takeNumber)} onChange={() => {}} placeholder="—" className="opacity-60 cursor-default" />
            </Field>
          </div>

          {/* Camera */}
          <SectionHeader title="Camera" />
          <div className="grid grid-cols-2 sm:grid-cols-3 lg:grid-cols-4 gap-3">
            <Field label="Camera Letter">
              <TF value={str(fields.cameraLetter)} onChange={(v) => set("cameraLetter", v || null)} placeholder="A" />
            </Field>
            <Field label="Clip Name" className="sm:col-span-2">
              <TF value={str(fields.clipName)} onChange={(v) => set("clipName", v || null)} placeholder="A001_C001" />
            </Field>
            <Field label="Roll">
              <TF value={str(fields.roll)} onChange={(v) => set("roll", v || null)} placeholder="A001" />
            </Field>
            <Field label="Camera Model" className="sm:col-span-2">
              <TF value={str(fields.cameraModel)} onChange={(v) => set("cameraModel", v || null)} placeholder="Alexa Mini LF" />
            </Field>
            <Field label="Resolution">
              <TF value={str(fields.resolution)} onChange={(v) => set("resolution", v || null)} placeholder="4.5K" />
            </Field>
            <Field label="Codec">
              <TF value={str(fields.codec)} onChange={(v) => set("codec", v || null)} placeholder="ARRIRAW" />
            </Field>
            <Field label="FPS">
              <TF
                type="number"
                value={num(fields.fps)}
                onChange={(v) => set("fps", v ? Number(v) : null)}
                placeholder="24"
              />
            </Field>
            <Field label="Shutter">
              <TF value={str(fields.shutter)} onChange={(v) => set("shutter", v || null)} placeholder="180°" />
            </Field>
            <Field label="ISO">
              <TF
                type="number"
                value={num(fields.iso)}
                onChange={(v) => set("iso", v ? Number(v) : null)}
                placeholder="800"
              />
            </Field>
            <Field label="White Balance">
              <TF
                type="number"
                value={num(fields.whiteBalance)}
                onChange={(v) => set("whiteBalance", v ? Number(v) : null)}
                placeholder="5600"
              />
            </Field>
            <Field label="Colour Space" className="sm:col-span-2">
              <TF value={str(fields.colourSpace)} onChange={(v) => set("colourSpace", v || null)} placeholder="LogC3 AWG3" />
            </Field>
          </div>

          {/* Lens */}
          <SectionHeader title="Lens" />
          <div className="grid grid-cols-2 sm:grid-cols-3 lg:grid-cols-4 gap-3">
            <Field label="Lens Set" className="sm:col-span-2">
              <TF value={str(fields.lensSet)} onChange={(v) => set("lensSet", v || null)} placeholder="Cooke S4" />
            </Field>
            <Field label="Lens">
              <TF value={str(fields.lens)} onChange={(v) => set("lens", v || null)} placeholder="50mm" />
            </Field>
            <Field label="T Stop">
              <TF value={str(fields.tStop)} onChange={(v) => set("tStop", v || null)} placeholder="T2.8" />
            </Field>
            <Field label="Filters" className="sm:col-span-2">
              <TF value={str(fields.filters)} onChange={(v) => set("filters", v || null)} placeholder="IRND 0.6" />
            </Field>
            <Field label="Anamorphic">
              <button
                onClick={() => set("isAnamorphic", !fields.isAnamorphic)}
                className={cn(
                  "h-9 px-3 rounded-lg border text-xs font-medium transition-colors text-left",
                  fields.isAnamorphic
                    ? "bg-amber-500/20 border-amber-600 text-amber-300"
                    : "bg-zinc-900 border-zinc-700 text-zinc-500"
                )}
              >
                {fields.isAnamorphic ? "Yes" : "No"}
              </button>
            </Field>
          </div>

          {/* Tracking */}
          <SectionHeader title="Tracking" />
          <div className="flex flex-wrap gap-2">
            {TRACKING_ITEMS.map(({ key, label }) => {
              const checked = fields[key] as boolean;
              return (
                <button
                  key={key}
                  onClick={() => set(key as keyof FullTake, !checked as never)}
                  className={cn(
                    "px-3 py-2 rounded-lg border text-xs font-medium transition-all min-h-[36px]",
                    checked
                      ? "bg-amber-500/15 border-amber-600/60 text-amber-300"
                      : "bg-zinc-900 border-zinc-700 text-zinc-500 hover:border-zinc-600 hover:text-zinc-400"
                  )}
                >
                  {label}
                </button>
              );
            })}
          </div>

          {/* Environment */}
          <SectionHeader title="Environment" />
          <div className="grid grid-cols-2 sm:grid-cols-3 gap-3">
            <Field label="Weather" className="sm:col-span-1">
              <TF value={str(fields.weather)} onChange={(v) => set("weather", v || null)} placeholder="Overcast" />
            </Field>
            <Field label="Sun Direction">
              <TF value={str(fields.sunDirection)} onChange={(v) => set("sunDirection", v || null)} placeholder="NW high" />
            </Field>
            <Field label="Artificial Lights" className="sm:col-span-3">
              <Textarea
                value={str(fields.artificialLights)}
                onChange={(e) => set("artificialLights", e.target.value || null)}
                placeholder="2x HMI 12K softbox, practical tungsten..."
                className="bg-zinc-900 border-zinc-700 text-sm min-h-[72px] resize-none"
              />
            </Field>
          </div>

          {/* Supervisor */}
          <SectionHeader title="Supervisor" />
          <div className="grid gap-3">
            <Field label="Notes">
              <Textarea
                value={str(fields.supervisorNotes)}
                onChange={(e) => set("supervisorNotes", e.target.value || null)}
                placeholder="General notes on this take..."
                className="bg-zinc-900 border-zinc-700 text-sm min-h-[80px] resize-none"
              />
            </Field>
            <Field label="Continuity">
              <Textarea
                value={str(fields.continuityNotes)}
                onChange={(e) => set("continuityNotes", e.target.value || null)}
                placeholder="Continuity concerns..."
                className="bg-zinc-900 border-zinc-700 text-sm min-h-[72px] resize-none"
              />
            </Field>
            <Field label="VFX Requirements">
              <Textarea
                value={str(fields.vfxRequirements)}
                onChange={(e) => set("vfxRequirements", e.target.value || null)}
                placeholder="Screen replacement, wire removal, creature interaction..."
                className="bg-zinc-900 border-zinc-700 text-sm min-h-[72px] resize-none"
              />
            </Field>
          </div>

          {/* Images */}
          <SectionHeader title="Reference Images" />
          <TakeImageGallery
            takeId={take.id}
            attachments={fields.attachments}
            onChange={(attachments) => {
              setFields((f) => ({ ...f, attachments }));
              onAttachmentsChange();
            }}
          />

          {/* Previous Take comparison */}
          {previousTake && (
            <div>
              <button
                onClick={() => setShowPrevPanel((p) => !p)}
                className="flex items-center gap-2 text-xs text-zinc-500 hover:text-zinc-300 transition-colors mb-2"
              >
                {showPrevPanel ? <ChevronUp className="h-3.5 w-3.5" /> : <ChevronDown className="h-3.5 w-3.5" />}
                Compare with Take {previousTake.takeNumber}
              </button>
              {showPrevPanel && (
                <PreviousTakePanel current={fields} previous={previousTake} />
              )}
            </div>
          )}

          {/* Bottom padding */}
          <div className="h-8" />
        </div>
      </div>
    </div>
  );
}