"use client";

import { useCallback, useState } from "react";
import { 
  Sparkles, 
  Settings2, 
  Clock, 
  Zap, 
  Tv2, 
  LoaderCircle,
  CheckCircle2,
  Target,
} from "lucide-react";
import type { LucideIcon } from "lucide-react";
import { Modal, PrimaryButton, SecondaryButton } from "@/components/dashboard/dashboardPrimitives";
import { useJobPolling } from "@/hooks/useJobPolling";
import { getVideoPlanExtended } from "@/lib/api/intelligence";
import { createVideoRenderJob, createVideoScenePlan, getVideoRenderJob } from "@/lib/api/video";
import { normalizeApiError } from "@/lib/api/client";
import type {
  StudentLevel,
  VideoFormat,
  VideoPlanV2Response,
  VideoPlanDurationType,
  VideoPlanStyle,
  VideoRenderJob,
  VoiceMode,
  VoiceProfile,
} from "@/lib/api/types";
import { prepareScenePlanForRender } from "@/lib/video/durations";
import { cn } from "@/lib/utils";

const ALLOW_LOCAL_PREVIEW_AUDIO = process.env.NODE_ENV !== "production";

const durationOptions: { value: VideoPlanDurationType; label: string; time: string; icon: LucideIcon }[] = [
  { value: "quick_concept", label: "5-minute video", time: "5 min", icon: Zap },
  { value: "exam_focus", label: "10-minute video", time: "10 min", icon: Target },
  { value: "deep_masterclass", label: "30-minute video", time: "30 min", icon: Tv2 },
];

const styleOptions: { value: VideoPlanStyle; label: string; desc: string }[] = [
  { value: "normal_teacher", label: "Normal Teacher", desc: "Traditional academic style" },
  { value: "visual_tutor", label: "Visual Tutor", desc: "Heavy on diagrams & flowcharts" },
  { value: "anime_tutor", label: "Anime Tutor", desc: "High energy, character-led" },
  { value: "malayalam_english_tutor", label: "Mixed Mode", desc: "Malayalam + English key terms" },
  { value: "exam_war_mode", label: "Exam War Mode", desc: "Strictly mark-focused, fast-paced" },
];

const formatOptions: { value: VideoFormat; label: string }[] = [
  { value: "16:9", label: "Wide Class Video" },
  { value: "9:16", label: "Phone Revision" },
];

const voiceOptions: { value: VoiceProfile; label: string; voiceMode: VoiceMode }[] = [
  { value: "anime_female_tutor", label: "Anime Tutor", voiceMode: "english_soft" },
  { value: "calm_teacher", label: "Calm Teacher", voiceMode: "english_soft" },
  { value: "malayalam_english_teacher", label: "Malayalam + English Tutor", voiceMode: "ml_en_mix" },
  { value: "exam_war_coach", label: "Exam War Coach", voiceMode: "english_soft" },
  { value: "premium_human_teacher", label: "Premium Human Teacher", voiceMode: "english_soft" },
];

export function VideoTutorBrainModal({
  isOpen,
  onClose,
  documentId,
  studentLevel,
  onPlanGenerated
}: {
  isOpen: boolean;
  onClose: () => void;
  documentId: string;
  studentLevel: StudentLevel;
  onPlanGenerated: (plan: VideoPlanV2Response) => void;
}) {
  const [step, setStep] = useState<"config" | "loading" | "success">("config");
  const [duration, setDuration] = useState<VideoPlanDurationType>("exam_focus");
  const [style, setStyle] = useState<VideoPlanStyle>("visual_tutor");
  const [format, setFormat] = useState<VideoFormat>("16:9");
  const [voiceProfile, setVoiceProfile] = useState<VoiceProfile>("calm_teacher");
  const [generatedPlan, setGeneratedPlan] = useState<VideoPlanV2Response | null>(null);
  const [renderStep, setRenderStep] = useState<"idle" | "planning" | "voice" | "building" | "ready" | "failed">("idle");
  const [renderJob, setRenderJob] = useState<VideoRenderJob | null>(null);
  const [error, setError] = useState<string | null>(null);

  const pollRenderJob = useCallback(async () => {
    if (!renderJob) throw new Error("No video render job is running.");
    return getVideoRenderJob(renderJob.id);
  }, [renderJob]);

  useJobPolling({
    enabled: Boolean(renderJob && (renderJob.status === "queued" || renderJob.status === "running")),
    fetcher: pollRenderJob,
    shouldContinue: (job) => job.status === "queued" || job.status === "running",
    onData: (job) => {
      setRenderJob(job);
      if (job.status === "ready") {
        setRenderStep("ready");
      } else if (job.status === "failed") {
        setRenderStep("failed");
        setError("DocDoe could not finish this video. Try again from a shorter source.");
      } else if (job.current_step?.startsWith("generating_audio")) {
        setRenderStep("voice");
      } else {
        setRenderStep("building");
      }
    },
    onError: () => setError("DocDoe could not refresh the video status. Open Videos to check it."),
  });

  async function generatePlan() {
    setStep("loading");
    setError(null);
    try {
      const data = await getVideoPlanExtended(documentId, duration, style);
      setGeneratedPlan(data);
      setStep("success");
      onPlanGenerated(data);
    } catch (caughtError) {
      setError(normalizeApiError(caughtError));
      setStep("config");
    }
  }

  async function buildVideo() {
    setRenderStep("planning");
    setError(null);
    try {
      const selectedVoice = voiceOptions.find((option) => option.value === voiceProfile) ?? voiceOptions[1];
      const durationMinutes =
        duration === "quick_concept" ? 5 :
        duration === "exam_focus" ? 10 :
        duration === "deep_masterclass" ? 30 :
        10;
      const scenePlan = prepareScenePlanForRender(
        await createVideoScenePlan({
          document_id: documentId,
          title: generatedPlan?.title ?? "DocDoe Study Video",
          language: selectedVoice.voiceMode === "ml_en_mix" ? "Malayalam + English" : "English",
          duration_minutes: durationMinutes,
          visual_style: style === "anime_tutor" ? "anime_visual_explainer" : "clean_explainer",
          video_format: format,
        }),
        durationMinutes * 60,
      );
      setRenderStep("voice");
      const job = await createVideoRenderJob({
        scene_plan: scenePlan,
        title: scenePlan.title,
        allow_mock_audio: ALLOW_LOCAL_PREVIEW_AUDIO,
        voice_mode: selectedVoice.voiceMode,
        voice: selectedVoice.value,
        language: scenePlan.language,
      });
      setRenderJob(job);
      setRenderStep(job.status === "ready" ? "ready" : "building");
    } catch (caughtError) {
      setError(normalizeApiError(caughtError));
      setRenderStep("failed");
    }
  }

  return (
    <Modal isOpen={isOpen} onClose={onClose} title="Video Tutor Brain V2">
      {step === "config" && (
        <div className="space-y-6 py-2">
          <div className="space-y-3">
             <p className="flex items-center gap-2 text-[11px] font-bold text-violet-400 uppercase tracking-widest">
               <Clock className="size-3" />
               Select Duration
             </p>
             <div className="grid grid-cols-2 gap-2">
                {durationOptions.map((opt) => (
                  <button
                    key={opt.value}
                    onClick={() => setDuration(opt.value)}
                    className={cn(
                      "p-3 rounded-2xl border text-left transition-all",
                      duration === opt.value
                        ? "border-violet-500 bg-violet-500/10 shadow-[0_0_20px_rgba(124,58,237,0.15)]"
                        : "border-white/5 bg-white/[0.02] hover:border-white/10"
                    )}
                  >
                    <opt.icon className={cn("size-4 mb-2", duration === opt.value ? "text-violet-400" : "text-white/20")} />
                    <p className="text-[12px] font-bold text-white">{opt.label}</p>
                    <p className="text-[10px] font-medium text-white/30">{opt.time}</p>
                  </button>
                ))}
             </div>
          </div>

          <div className="space-y-3">
             <p className="flex items-center gap-2 text-[11px] font-bold text-violet-400 uppercase tracking-widest">
               <Settings2 className="size-3" />
               Teaching Style
             </p>
             <div className="grid gap-2">
                {styleOptions.map((opt) => (
                  <button
                    key={opt.value}
                    onClick={() => setStyle(opt.value)}
                    className={cn(
                      "flex items-center justify-between p-3 rounded-xl border transition-all text-left",
                      style === opt.value
                        ? "border-violet-500 bg-violet-500/10"
                        : "border-white/5 bg-white/[0.02] hover:bg-white/[0.04]"
                    )}
                  >
                    <div className="min-w-0">
                       <p className="text-[12px] font-bold text-white">{opt.label}</p>
                       <p className="text-[10px] font-medium text-white/30 truncate">{opt.desc}</p>
                    </div>
                    {style === opt.value && <CheckCircle2 className="size-4 text-violet-400 shrink-0" />}
                  </button>
                ))}
             </div>
          </div>

          <div className="grid gap-3 sm:grid-cols-2">
            <div className="space-y-2">
              <p className="text-[11px] font-bold text-violet-400 uppercase tracking-widest">Format</p>
              <div className="grid gap-2">
                {formatOptions.map((opt) => (
                  <button
                    key={opt.value}
                    onClick={() => setFormat(opt.value)}
                    className={cn(
                      "rounded-xl border px-3 py-2 text-left text-[12px] font-bold transition",
                      format === opt.value ? "border-violet-500 bg-violet-500/10 text-white" : "border-white/5 bg-white/[0.02] text-white/50",
                    )}
                  >
                    {opt.label}
                  </button>
                ))}
              </div>
            </div>
            <div className="space-y-2">
              <p className="text-[11px] font-bold text-violet-400 uppercase tracking-widest">Voice</p>
              <select
                value={voiceProfile}
                onChange={(event) => setVoiceProfile(event.target.value as VoiceProfile)}
                className="h-10 w-full rounded-xl border border-white/5 bg-black/40 px-3 text-[12px] font-bold text-white outline-none"
              >
                {voiceOptions.map((option) => (
                  <option key={option.value} value={option.value}>{option.label}</option>
                ))}
              </select>
              <p className="text-[10.5px] leading-4 text-white/32">Current level: {studentLevel}. Long videos can take more time to prepare.</p>
            </div>
          </div>

          {error ? (
            <p className="rounded-2xl border border-rose-300/12 bg-rose-500/[0.06] px-3 py-2 text-[12px] leading-5 text-rose-50/70">
              {error}
            </p>
          ) : null}

          <PrimaryButton onClick={generatePlan} className="w-full h-12 shadow-[0_0_30px_rgba(124,58,237,0.2)]">
            <Sparkles className="size-4" />
            Generate Extended Video Plan
          </PrimaryButton>
        </div>
      )}

      {step === "loading" && (
        <div className="py-20 flex flex-col items-center justify-center gap-4 text-center px-6">
           <div className="relative">
              <div className="absolute inset-0 bg-violet-500/20 blur-3xl rounded-full animate-pulse" />
              <LoaderCircle className="relative size-12 animate-spin text-violet-400" strokeWidth={1.5} />
           </div>
           <div className="space-y-1">
              <p className="text-[15px] font-bold text-white tracking-tight">DocDoe is building your study video plan.</p>
              <p className="text-[12px] text-white/40">Creating hook, analogy, and source-based teaching flow for your {duration.replace("_", " ")} video.</p>
           </div>
        </div>
      )}

      {step === "success" && generatedPlan && (
        <div className="space-y-6 py-2">
           <div className="flex items-center gap-4 p-4 rounded-[24px] bg-emerald-500/10 border border-emerald-500/20">
              <div className="size-10 grid place-items-center rounded-xl bg-emerald-500/20 text-emerald-400">
                 <CheckCircle2 className="size-6" />
              </div>
              <div className="min-w-0">
                 <p className="text-[11px] font-bold text-emerald-400 uppercase tracking-wider">Plan Ready</p>
                 <h3 className="text-[15px] font-bold text-white truncate">{generatedPlan.title}</h3>
              </div>
           </div>

           <div className="space-y-4">
              <div className="space-y-1.5">
                 <p className="text-[10px] font-bold text-white/30 uppercase tracking-widest">Master Script Hook</p>
                 <div className="p-3 rounded-xl bg-white/5 border border-white/5 text-[13px] text-white/70 italic leading-relaxed">
                    &quot;{generatedPlan.hook}&quot;
                 </div>
              </div>
              
              <div className="space-y-1.5">
                 <p className="text-[10px] font-bold text-white/30 uppercase tracking-widest">The Analogy</p>
                 <p className="text-[13px] text-white/80 font-medium px-1">{generatedPlan.analogy}</p>
              </div>

              <div className="space-y-2">
                 <p className="text-[10px] font-bold text-white/30 uppercase tracking-widest">Scene Breakdown ({generatedPlan.sections.length} scenes)</p>
                 <div className="grid gap-2">
                    {generatedPlan.sections.map(s => (
                       <div key={s.scene_number} className="flex gap-3 p-2.5 rounded-xl bg-black/20 border border-white/5">
                          <span className="text-[11px] font-black text-violet-400/50 mt-0.5">#{s.scene_number}</span>
                          <div className="min-w-0">
                             <p className="text-[12px] font-bold text-white/90">{s.label}</p>
                             <p className="text-[11px] text-white/40 mt-1">{s.visual_suggestion}</p>
                          </div>
                       </div>
                    ))}
                 </div>
              </div>
           </div>

           {renderStep !== "idle" ? (
             <div className="rounded-2xl border border-white/5 bg-white/[0.03] p-3">
               <p className="text-[11px] font-bold uppercase tracking-wider text-violet-200/70">
                 {renderStep === "planning" ? "Preparing" :
                  renderStep === "voice" ? "Adding voice" :
                  renderStep === "building" ? "Building" :
                  renderStep === "ready" ? "Your video is ready" :
                  "Could not build video"}
               </p>
               {renderJob ? (
                 <p className="mt-1 text-[12px] text-white/52">Open Videos to track progress and preview the final study video.</p>
               ) : error ? (
                 <p className="mt-1 text-[12px] text-rose-50/70">{error}</p>
               ) : (
                 <p className="mt-1 text-[12px] text-white/42">Long videos can take more time to prepare.</p>
               )}
             </div>
           ) : null}

           <div className="grid grid-cols-2 gap-3">
              <SecondaryButton onClick={() => setStep("config")} className="h-11">Edit Config</SecondaryButton>
              <PrimaryButton onClick={buildVideo} disabled={renderStep === "planning" || renderStep === "voice" || renderStep === "building"} className="h-11">
                {renderStep === "idle" || renderStep === "failed" ? "Build Video" : renderStep === "ready" ? "Build Again" : "Preparing"}
              </PrimaryButton>
           </div>
           {renderStep === "ready" ? (
             <PrimaryButton onClick={onClose} className="w-full h-11">Close & Save</PrimaryButton>
           ) : null}
        </div>
      )}
    </Modal>
  );
}