"use client"

import { useState, useEffect, useRef, Suspense } from "react"
import { useSearchParams, useRouter } from "next/navigation"
import { Eye, EyeOff, Loader2 } from "lucide-react"

const WEBSITE_THEME_KEY = "crm-website-theme"

const waves = [
  { a: 16, f: 0.011, s: 0.018, y: 0.38, fill: "rgba(27,176,206,0.18)" },
  { a: 20, f: 0.008, s: 0.013, y: 0.52, fill: "rgba(27,176,206,0.25)" },
  { a: 12, f: 0.015, s: 0.025, y: 0.28, fill: "rgba(180,192,210,0.06)" },
  { a: 26, f: 0.006, s: 0.010, y: 0.65, fill: "rgba(180,192,210,0.15)" },
  { a: 10, f: 0.019, s: 0.030, y: 0.20, fill: "rgba(27,176,206,0.10)" },
]

export default function LoginPage() {
  return (
    <Suspense fallback={
      <div className="flex min-h-screen bg-[#0a0a0f] items-center justify-center">
        <div className="w-8 h-8 border-2 border-[#1BB0CE] border-t-transparent rounded-full animate-spin" />
      </div>
    }>
      <LoginForm />
    </Suspense>
  )
}

function LoginForm() {
  const router = useRouter()
  const searchParams = useSearchParams()
  const [email, setEmail] = useState("")
  const [password, setPassword] = useState("")
  const [showPassword, setShowPassword] = useState(false)
  const [loading, setLoading] = useState(false)
  const [remember, setRemember] = useState(false)
  const [error, setError] = useState("")
  const [counts, setCounts] = useState({ leads: 0, conversion: 0, users: 0 })
  const counterStarted = useRef(false)
  const [testimonialIndex, setTestimonialIndex] = useState(0)

  const testimonials = [
    {
      text: "This CRM transformed how we manage our sales pipeline. We've seen a 40% increase in lead conversion.",
      author: "Marcus Johnson, Sales Lead at Black Cipher",
    },
    {
      text: "When you're not sure, flip a coin, because when the coin is in the air, you realize which option you're actually hoping for.",
      author: "Dillen van der Merwe, Madman of Black Cipher",
    },
  ]

  useEffect(() => {
    const timer = setInterval(() => {
      setTestimonialIndex((prev) => (prev + 1) % testimonials.length)
    }, 5000)
    return () => clearInterval(timer)
  }, [testimonials.length])
  const canvasRef = useRef<HTMLCanvasElement>(null)
  const starsCanvasRightRef = useRef<HTMLCanvasElement>(null)

  useEffect(() => {
    const canvas = canvasRef.current
    if (!canvas) return
    const ctx = canvas.getContext("2d")
    if (!ctx) return

    let animId: number
    let time = 0

    const resize = () => {
      const parent = canvas.parentElement!
      const rect = parent.getBoundingClientRect()
      const dpr = window.devicePixelRatio || 1
      canvas.width = rect.width * dpr
      canvas.height = 200 * dpr
      canvas.style.width = rect.width + "px"
      canvas.style.height = "200px"
      ctx!.setTransform(dpr, 0, 0, dpr, 0, 0)
    }

    resize()
    window.addEventListener("resize", resize)

    const draw = () => {
      const w = canvas.width / (window.devicePixelRatio || 1)
      const h = 200
      ctx!.clearRect(0, 0, w, h)

      for (const wave of waves) {
        ctx!.beginPath()
        ctx!.moveTo(0, h)
        for (let x = 0; x <= w; x++) {
          const y = wave.y * h + Math.sin(x * wave.f + time * wave.s) * wave.a
          ctx!.lineTo(x, y)
        }
        ctx!.lineTo(w, h)
        ctx!.closePath()
        ctx!.fillStyle = wave.fill
        ctx!.fill()
      }

      time += 1
      animId = requestAnimationFrame(draw)
    }

    animId = requestAnimationFrame(draw)

    return () => {
      cancelAnimationFrame(animId)
      window.removeEventListener("resize", resize)
    }
  }, [])

  useEffect(() => {
    const canvases = [starsCanvasRightRef.current].filter(Boolean) as HTMLCanvasElement[]
    if (canvases.length === 0) return

    const stars = Array.from({ length: 312 }, () => ({
      x: Math.random(),
      y: Math.random(),
      r: 0.2 + Math.random() * 0.6,
      baseOpacity: 0.12 + Math.random() * 0.43,
      speed: 0.003 + Math.random() * 0.015,
      phase: Math.random() * Math.PI * 2,
      driftX: (Math.random() - 0.5) * 0.00003,
      driftY: (Math.random() - 0.5) * 0.00003,
    }))

    let animId: number
    let time = 0

    const resize = () => {
      for (const c of canvases) {
        const dpr = window.devicePixelRatio || 1
        const rect = c.getBoundingClientRect()
        c.width = rect.width * dpr
        c.height = rect.height * dpr
        const ctx = c.getContext("2d")
        if (ctx) ctx.setTransform(dpr, 0, 0, dpr, 0, 0)
      }
    }

    resize()
    const ros = canvases.map((c) => {
      const ro = new ResizeObserver(() => resize())
      ro.observe(c.parentElement!)
      return ro
    })
    window.addEventListener("resize", resize)

    const draw = () => {
      time += 1
      for (const c of canvases) {
        const dpr = window.devicePixelRatio || 1
        const w = c.width / dpr
        const h = c.height / dpr
        const ctx = c.getContext("2d")
        if (!ctx) continue
        ctx.clearRect(0, 0, w, h)

        for (const star of stars) {
          const x = ((star.x + time * star.driftX) % 1) * w
          const y = ((star.y + time * star.driftY) % 1) * h
          const opacity = star.baseOpacity * (0.5 + 0.5 * Math.sin(time * star.speed + star.phase))

          ctx.beginPath()
          ctx.arc(x, y, star.r, 0, Math.PI * 2)
          ctx.fillStyle = `rgba(255,255,255,${opacity})`
          ctx.fill()

          if (star.r > 0.5) {
            ctx.beginPath()
            ctx.arc(x, y, star.r * 1.8, 0, Math.PI * 2)
            ctx.fillStyle = `rgba(255,255,255,${opacity * 0.06})`
            ctx.fill()
          }
        }
      }

      animId = requestAnimationFrame(draw)
    }

    animId = requestAnimationFrame(draw)

    return () => {
      cancelAnimationFrame(animId)
      ros.forEach((ro) => ro.disconnect())
      window.removeEventListener("resize", resize)
    }
  }, [])

  useEffect(() => {
    if (counterStarted.current) return
    counterStarted.current = true
    const targets = { leads: 1247, conversion: 40, users: 83 }
    const steps = 150

    const delayTimer = setTimeout(() => {
      let step = 0
      const interval = setInterval(() => {
        step++
        if (step >= steps) {
          clearInterval(interval)
          setCounts(targets)
          return
        }
        setCounts({
          leads: Math.min(Math.floor((targets.leads / steps) * step), targets.leads),
          conversion: Math.min(Math.floor((targets.conversion / steps) * step), targets.conversion),
          users: Math.min(Math.floor((targets.users / steps) * step), targets.users),
        })
      }, 15)
    }, 400)

    return () => clearTimeout(delayTimer)
  }, [])

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault()
    setError("")
    setLoading(true)

    try {
      const res = await fetch("/api/auth/login", {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({ email, password }),
      })

      if (res.ok) {
        localStorage.removeItem(WEBSITE_THEME_KEY)
        const root = document.documentElement
        root.className = root.className.split(" ").filter((c) => !c.startsWith("theme-")).join(" ").trim()
        const redirectTo = searchParams.get("redirect") || "/dashboard"
        router.push(redirectTo)
      } else {
        const data = await res.json().catch(() => ({}))
        setError(data.error || "Invalid email or password.")
      }
    } catch {
      setError("Connection error. Please try again.")
    } finally {
      setLoading(false)
    }
  }

  return (
    <div className="flex min-h-screen bg-[#0a0a0f]">
        <div className="left-panel flex flex-1 flex-col p-12">
          <div className="relative z-10 flex-1 flex items-center justify-center">
            <div className="text-center">
              <div className="bc-logo mb-8" style={{"--theme-primary":"#1BB0CE"} as React.CSSProperties}>
                Black <span className="accent">Cipher</span>
              </div>
              <h1 className="text-[34px] font-extrabold text-[#e8e8ef] leading-tight tracking-[-0.6px]">
                Your Agency&apos;s{" "}
                <span className="growth-word">Growth</span>{" "}
                Starts Here
              </h1>
              <p className="mt-4 text-[13px] leading-[1.7] max-w-[360px] mx-auto body-text">
                Manage leads, track conversions, and grow your web development business with our CRM.
              </p>
              <div className="stats-row">
                <div className="stat">
                  <div className="stat-number">{counts.leads.toLocaleString()}</div>
                  <div className="stat-label">leads tracked</div>
                </div>
                <div className="stat">
                  <div className="stat-number">{counts.conversion}%</div>
                  <div className="stat-label">conversion lift</div>
                </div>
                <div className="stat">
                  <div className="stat-number">{counts.users}</div>
                  <div className="stat-label">active users</div>
                </div>
              </div>
            </div>
          </div>

          <div className="relative z-10 testimonial" style={{ background: "rgba(255,255,255,0.7)", padding: "16px 20px 16px 16px", clipPath: "url(#testimonialClip)" }}>
            <svg width="0" height="0" style={{ position: "absolute" }}>
              <defs>
                <clipPath id="testimonialClip" clipPathUnits="objectBoundingBox">
                  <path d="M0,0 L0.92,0 C0.96,0 1,0.03 1,0.08 C1,0.14 0.97,0.22 0.9,0.3 C0.85,0.36 0.83,0.42 0.83,0.5 C0.83,0.58 0.85,0.64 0.9,0.7 C0.97,0.78 1,0.86 1,0.92 C1,0.97 0.96,1 0.92,1 L0,1 Z" />
                </clipPath>
              </defs>
            </svg>
            <div className="transition-opacity duration-500" key={testimonialIndex}>
              <p className="text-sm font-semibold leading-relaxed" style={{ color: "#0a0a0f" }}>
                &ldquo;{testimonials[testimonialIndex].text}&rdquo;
              </p>
              <p className="text-xs font-bold mt-2" style={{ color: "#0a0a0f" }}>
                {testimonials[testimonialIndex].author}
              </p>
            </div>
            <div className="flex items-center justify-center gap-1.5 mt-3">
              {testimonials.map((_, i) => (
                <button
                  key={i}
                  type="button"
                  onClick={() => setTestimonialIndex(i)}
                  className={`h-1.5 rounded-full transition-all duration-300 ${i === testimonialIndex ? "w-5 bg-[#1BB0CE]" : "w-1.5 bg-[#1BB0CE]/30"}`}
                />
              ))}
            </div>
          </div>

          <canvas ref={canvasRef} className="wave-canvas" />
        </div>

        <div className="panel-divider" />

        <div className="right-panel flex items-center justify-center p-10">
          <canvas ref={starsCanvasRightRef} className="stars-canvas" />
          <div className="accent-line" />

          <div className="w-full" style={{ maxWidth: 340 }}>
            <h2 className="text-[24px] font-bold text-[#e8e8ef] tracking-[-0.3px] mb-[5px]">
              Welcome back
            </h2>
            <p className="text-[13px] mb-[26px] subheading-text">
              Sign in to your account to continue
            </p>

            {error && (
              <div className="mb-4 rounded bg-red-500/10 px-4 py-2 text-sm text-red-400">
                {error}
              </div>
            )}

            <form onSubmit={handleSubmit} className="space-y-5">
              <div>
                <label htmlFor="email" className="login-label">
                  Email
                </label>
                <div className="input-sheen">
                  <input
                    id="email"
                    type="email"
                    placeholder="name@company.com"
                    value={email}
                    onChange={(e) => setEmail(e.target.value)}
                    required
                    autoComplete="email"
                    className="login-input"
                  />
                </div>
              </div>

              <div>
                <div className="flex items-center justify-between mb-[6px]">
                  <label htmlFor="password" className="login-label" style={{ marginBottom: 0 }}>
                    Password
                  </label>
                  <button type="button" className="text-[12px] text-[#1BB0CE] hover:underline" onClick={() => alert("Please contact your administrator to reset your password.")}>
                    Forgot password?
                  </button>
                </div>
                <div className="input-sheen input-sheen-delayed">
                  <div className="relative">
                    <input
                      id="password"
                      type={showPassword ? "text" : "password"}
                      placeholder="Enter your password"
                      value={password}
                      onChange={(e) => setPassword(e.target.value)}
                      required
                      autoComplete="current-password"
                      className="login-input"
                    />
                    <button
                      type="button"
                      onClick={() => setShowPassword(!showPassword)}
                      className="password-toggle"
                    >
                      {showPassword ? (
                        <EyeOff className="h-4 w-4" />
                      ) : (
                        <Eye className="h-4 w-4" />
                      )}
                    </button>
                  </div>
                </div>
              </div>

              <label className="flex items-center gap-2 cursor-pointer">
                <input
                  type="checkbox"
                  checked={remember}
                  onChange={(e) => setRemember(e.target.checked)}
                  className="login-checkbox"
                />
                <span className="text-[13px] checkbox-text">
                  Remember me
                </span>
              </label>

              <button type="submit" className="auth-btn" disabled={loading}>
                {loading && <Loader2 className="h-4 w-4 animate-spin" />}
                {loading ? "Signing in..." : "Sign in"}
              </button>
            </form>

            <p className="text-center text-[11px] mt-4 footer-text">
              By signing in, you agree to our{" "}
              <button type="button" className="text-[#1BB0CE] hover:underline">
                Terms of Service
              </button>{" "}
              and{" "}
              <button type="button" className="text-[#1BB0CE] hover:underline">
                Privacy Policy
              </button>
            </p>
          </div>
        </div>
      </div>
  )
}