import React, { useMemo, useState } from "react";
import { motion } from "framer-motion";
import { Play, Pause, UploadCloud, Sparkles, Music, Settings2, Gauge, Share2, Wand2 } from "lucide-react";
import { ResponsiveContainer, RadialBarChart, RadialBar, PolarAngleAxis } from "recharts";
import {
  Card,
  CardContent,
  CardDescription,
  CardFooter,
  CardHeader,
  CardTitle,
} from "@/components/ui/card";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { Textarea } from "@/components/ui/textarea";
import { Label } from "@/components/ui/label";
import { Slider } from "@/components/ui/slider";
import { Switch } from "@/components/ui/switch";
import { Tabs, TabsContent, TabsList, TabsTrigger } from "@/components/ui/tabs";
import { Separator } from "@/components/ui/separator";

// --- Helper comps ---
const Stat = ({ label, value, hint }: { label: string; value: string; hint?: string }) => (
  <div className="flex flex-col">
    <span className="text-xs text-muted-foreground">{label}</span>
    <span className="font-semibold">{value}</span>
    {hint ? <span className="text-[11px] text-muted-foreground">{hint}</span> : null}
  </div>
);

const ScoreGauge = ({ score = 72, label = "Algorithm Fit" }: { score?: number; label?: string }) => {
  const data = useMemo(() => [{ name: label, value: score, fill: "hsl(var(--primary))" }], [score, label]);
  return (
    <div className="h-40 w-40">
      <ResponsiveContainer>
        <RadialBarChart innerRadius="70%" outerRadius="100%" data={data} startAngle={220} endAngle={-40}>
          <PolarAngleAxis type="number" domain={[0, 100]} tick={false} />
          <RadialBar dataKey="value" cornerRadius={20} />
        </RadialBarChart>
      </ResponsiveContainer>
      <div className="-mt-24 text-center">
        <div className="text-3xl font-bold">{score}</div>
        <div className="text-xs text-muted-foreground">{label}</div>
      </div>
    </div>
  );
};

export default function PromptComposer() {
  const [prompt, setPrompt] = useState("Upbeat 115 BPM house track with soulful vocals; short 5s intro; bright mix; optimized for workout playlists.");
  const [title, setTitle] = useState("Moving On (Pop‑Punk Revival)");
  const [tempo, setTempo] = useState(115);
  const [lufs, setLufs] = useState(-14);
  const [autoMaster, setAutoMaster] = useState(true);
  const [generating, setGenerating] = useState(false);
  const [playing, setPlaying] = useState(false);

  const score = useMemo(() => {
    // Fake score from inputs (for mock only)
    let s = 60 + Math.min(20, Math.max(0, 120 - Math.abs(120 - tempo)) / 2);
    s += autoMaster ? 8 : 0;
    s += lufs >= -14 && lufs <= -13 ? 6 : 0;
    return Math.min(99, Math.round(s));
  }, [tempo, lufs, autoMaster]);

  const recs = useMemo(() => {
    const list: string[] = [];
    if (prompt.toLowerCase().includes("intro") === false) list.push("Add a clear hook within first 10s to reduce early skips.");
    if (lufs < -16) list.push("Raise loudness toward −14 LUFS (Spotify norm)." );
    if (tempo < 100) list.push("Consider +10–15 BPM for workout playlists.");
    list.push("Tag with 3–5 micro‑genres your audience actually searches.");
    list.push("Add call‑to‑action in description (save/share)." );
    return list;
  }, [prompt, lufs, tempo]);

  const handleGenerate = async () => {
    setGenerating(true);
    await new Promise(r => setTimeout(r, 1200)); // simulate
    setGenerating(false);
  };

  return (
    <div className="mx-auto max-w-6xl p-6 space-y-6">
      <div className="flex items-center gap-3">
        <motion.div initial={{ opacity: 0, y: -6 }} animate={{ opacity: 1, y: 0 }}>
          <Sparkles className="h-6 w-6 text-primary" />
        </motion.div>
        <h1 className="text-2xl md:text-3xl font-semibold">Prompt Composer — AI‑Aware Music Creation</h1>
      </div>

      <Card className="shadow-sm">
        <CardHeader>
          <CardTitle className="flex items-center gap-2"><Wand2 className="h-5 w-5"/> Compose from Prompt</CardTitle>
          <CardDescription>Describe your track. We’ll structure it for generation and platform algorithms.</CardDescription>
        </CardHeader>
        <CardContent className="space-y-4">
          <div className="grid md:grid-cols-2 gap-4">
            <div className="space-y-3">
              <Label htmlFor="prompt">Music prompt</Label>
              <Textarea id="prompt" value={prompt} onChange={e => setPrompt(e.target.value)} className="min-h-[110px]" />
              <div className="grid grid-cols-3 gap-3">
                <div>
                  <Label>Tempo (BPM)</Label>
                  <div className="flex items-center gap-3">
                    <Slider value={[tempo]} min={70} max={200} step={1} onValueChange={(v) => setTempo(v[0])} />
                    <div className="w-10 text-right text-sm">{tempo}</div>
                  </div>
                </div>
                <div>
                  <Label>Target loudness (LUFS)</Label>
                  <div className="flex items-center gap-3">
                    <Slider value={[lufs]} min={-20} max={-10} step={0.5} onValueChange={(v) => setLufs(v[0])} />
                    <div className="w-12 text-right text-sm">{lufs}</div>
                  </div>
                </div>
                <div className="flex items-center gap-3 pt-6">
                  <Switch checked={autoMaster} onCheckedChange={setAutoMaster} id="am" />
                  <Label htmlFor="am">Auto‑master</Label>
                </div>
              </div>
            </div>
            <div className="space-y-3">
              <Label>Working title</Label>
              <Input value={title} onChange={e => setTitle(e.target.value)} />
              <div className="grid grid-cols-2 gap-3">
                <Stat label="Hook ETA" value="0:08" hint="Aim &lt; 0:15" />
                <Stat label="Energy curve" value="Rising → Chorus" />
                <Stat label="Key (est.)" value="A minor" />
                <Stat label="Mood" value="Upbeat • Confident" />
              </div>
            </div>
          </div>
        </CardContent>
        <CardFooter className="flex items-center justify-between">
          <Button size="sm" variant="secondary" className="gap-2" onClick={() => setPrompt(p => p + (p.endsWith(".") ? "" : ".") + " Short 8s intro; keep vocals upfront; chorus by 0:20.")}>Quick improve</Button>
          <Button className="gap-2" onClick={handleGenerate} disabled={generating}>
            <Sparkles className="h-4 w-4"/>
            {generating ? "Generating…" : "Generate mock"}
          </Button>
        </CardFooter>
      </Card>

      <div className="grid md:grid-cols-3 gap-4">
        <Card>
          <CardHeader className="pb-2"><CardTitle className="flex items-center gap-2"><Gauge className="h-5 w-5"/> Algorithm Fit</CardTitle></CardHeader>
          <CardContent className="flex items-center justify-center">
            <ScoreGauge score={score} />
          </CardContent>
          <CardFooter className="text-xs text-muted-foreground">Based on tempo proximity, mastering target and intro/hook heuristics.</CardFooter>
        </Card>

        <Card>
          <CardHeader className="pb-2"><CardTitle className="flex items-center gap-2"><Settings2 className="h-5 w-5"/> Metadata Optimizer</CardTitle></CardHeader>
          <CardContent className="space-y-3 text-sm">
            <div>
              <Label>SoundCloud</Label>
              <ul className="list-disc pl-5 mt-1 space-y-1">
                <li>Genre: <b>house</b></li>
                <li>Tags: soulful, workout, vocal house, 115bpm</li>
                <li>Desc: “Hook by 0:08 • Bright mix • Save & share if it moves you.”</li>
              </ul>
            </div>
            <Separator />
            <div>
              <Label>Spotify</Label>
              <ul className="list-disc pl-5 mt-1 space-y-1">
                <li>Playlists fit: <b>Cardio</b>, <b>Dance Rising</b>, <b>mint Fresh</b></li>
                <li>Keywords: upbeat, energetic, vocal, gym</li>
                <li>Loudness target: −14 LUFS (true‑peak ≤ −1 dB)</li>
              </ul>
            </div>
          </CardContent>
        </Card>

        <Card>
          <CardHeader className="pb-2"><CardTitle className="flex items-center gap-2"><Music className="h-5 w-5"/> Prescriptive Advice</CardTitle></CardHeader>
          <CardContent>
            <ul className="list-disc pl-5 text-sm space-y-1">
              {recs.map((r, i) => (
                <li key={i}>{r}</li>
              ))}
            </ul>
          </CardContent>
        </Card>
      </div>

      <Card>
        <CardHeader>
          <CardTitle className="flex items-center gap-2"><Share2 className="h-5 w-5"/> Export & Upload (Mock)</CardTitle>
          <CardDescription>Preview how you'd ship this to platforms. Buttons are disabled in the mock.</CardDescription>
        </CardHeader>
        <CardContent className="grid md:grid-cols-3 gap-4">
          <Card className="border-dashed">
            <CardHeader>
              <CardTitle className="text-base">Audio</CardTitle>
              <CardDescription>2:57 • 115 BPM • A min</CardDescription>
            </CardHeader>
            <CardContent>
              <div className="flex items-center gap-3">
                <Button variant="secondary" size="icon" className="rounded-full" onClick={() => setPlaying(p=>!p)}>
                  {playing ? <Pause className="h-4 w-4"/> : <Play className="h-4 w-4"/>}
                </Button>
                <div className="text-sm text-muted-foreground">(Mock preview)</div>
              </div>
            </CardContent>
            <CardFooter>
              <Button size="sm" variant="outline" disabled className="gap-2"><UploadCloud className="h-4 w-4"/> Upload WAV</Button>
            </CardFooter>
          </Card>

          <Card className="border-dashed">
            <CardHeader>
              <CardTitle className="text-base">SoundCloud Package</CardTitle>
            </CardHeader>
            <CardContent className="text-sm space-y-2">
              <div>Title: <b>{title}</b></div>
              <div>Genre: <b>house</b></div>
              <div>Tags: soulful; workout; vocal‑house; 115bpm</div>
            </CardContent>
            <CardFooter>
              <Button size="sm" variant="outline" disabled className="gap-2"><UploadCloud className="h-4 w-4"/> Upload to SC</Button>
            </CardFooter>
          </Card>

          <Card className="border-dashed">
            <CardHeader>
              <CardTitle className="text-base">Spotify Package</CardTitle>
            </CardHeader>
            <CardContent className="text-sm space-y-2">
              <div>Title: <b>{title}</b></div>
              <div>Playlist pitch: cardio • dance rising • gym anthems</div>
              <div>Master target: −14 LUFS / −1 dBTP</div>
            </CardContent>
            <CardFooter>
              <Button size="sm" variant="outline" disabled className="gap-2"><UploadCloud className="h-4 w-4"/> Upload to Spotify</Button>
            </CardFooter>
          </Card>
        </CardContent>
      </Card>

      <div className="text-xs text-muted-foreground text-center">
        SIMULATED — No external calls. Replace with Suno/Udio + platform SDKs in a real build.
      </div>
    </div>
  );
}