import { useEffect, useState } from "react";
import type { MedicalAlert, PetProfileSummary } from "@groombook/types";
import { PetPhotoDisplay } from "./PetPhotoDisplay.js";

interface Props {
  petId: string;
}

type LoadState =
  | { status: "idle" }
  | { status: "loading" }
  | { status: "loaded"; data: PetProfileSummary }
  | { status: "error"; message: string };

function computeAge(dateOfBirth: string | null): string | null {
  if (!dateOfBirth) return null;
  const birth = new Date(dateOfBirth);
  const now = new Date();
  const totalMonths = (now.getFullYear() - birth.getFullYear()) * 12 + (now.getMonth() - birth.getMonth());
  if (totalMonths < 1) return "<1 mo";
  if (totalMonths < 12) return `${totalMonths} mo`;
  const years = Math.floor(totalMonths / 12);
  const months = totalMonths % 12;
  if (months === 0) return `${years} yr`;
  return `${years} yr ${months} mo`;
}

function TemperamentDots({ score }: { score: number }) {
  return (
    <div style={{ display: "flex", gap: 3, alignItems: "center" }}>
      {[1, 2, 3, 4, 5].map((n) => (
        <div
          key={n}
          style={{
            width: 10,
            height: 10,
            borderRadius: "50%",
            background: n <= score ? "var(--color-primary)" : "#e2e8f0",
          }}
        />
      ))}
    </div>
  );
}

const SEVERITY_STYLES: Record<MedicalAlert["severity"], { bg: string; color: string; border: string }> = {
  high: { bg: "#fef2f2", color: "#dc2626", border: "#fca5a5" },
  medium: { bg: "#fffbeb", color: "#d97706", border: "#fde68a" },
  low: { bg: "#eff6ff", color: "#2563eb", border: "#bfdbfe" },
};

function MedicalAlertBadge({ alert }: { alert: MedicalAlert }) {
  const s = SEVERITY_STYLES[alert.severity];
  return (
    <span
      style={{
        display: "inline-flex",
        alignItems: "center",
        gap: "0.25rem",
        fontSize: 11,
        fontWeight: 600,
        padding: "0.15rem 0.45rem",
        borderRadius: 99,
        background: s.bg,
        color: s.color,
        border: `1px solid ${s.border}`,
      }}
    >
      {alert.description}
    </span>
  );
}

function SectionLabel({ children }: { children: React.ReactNode }) {
  return (
    <div style={{ fontSize: 10, fontWeight: 700, color: "#9ca3af", letterSpacing: "0.05em", marginBottom: "0.25rem" }}>
      {children}
    </div>
  );
}

export function PetProfileCard({ petId }: Props) {
  const [state, setState] = useState<LoadState>({ status: "idle" });

  useEffect(() => {
    setState({ status: "loading" });
    fetch(`/api/pets/${petId}/profile-summary`)
      .then(async (res) => {
        if (!res.ok) throw new Error(`HTTP ${res.status}`);
        return res.json() as Promise<PetProfileSummary>;
      })
      .then((data) => setState({ status: "loaded", data }))
      .catch((e: unknown) => setState({ status: "error", message: e instanceof Error ? e.message : "Unknown error" }));
  }, [petId]);

  if (state.status === "idle" || state.status === "loading") {
    return (
      <div style={{
        border: "1px solid #e5e7eb",
        borderRadius: 10,
        padding: "1rem",
        background: "#fff",
        boxShadow: "0 1px 3px rgba(0,0,0,0.04)",
      }}>
        <div style={{ display: "flex", gap: "0.75rem", marginBottom: "0.75rem" }}>
          <div style={{ width: 64, height: 64, borderRadius: 12, background: "linear-gradient(90deg,#f0ebe4 25%,#e8e0d8 50%,#f0ebe4 75%)", backgroundSize: "200% 100%", animation: "shimmer 1.5s infinite", flexShrink: 0 }} />
          <div style={{ flex: 1 }}>
            <div style={{ height: 14, borderRadius: 4, background: "#f0ebe4", width: "60%", marginBottom: 6, animation: "shimmer 1.5s infinite", backgroundSize: "200% 100%" }} />
            <div style={{ height: 12, borderRadius: 4, background: "#f0ebe4", width: "40%", marginBottom: 6, animation: "shimmer 1.5s infinite", backgroundSize: "200% 100%" }} />
            <div style={{ height: 12, borderRadius: 4, background: "#f0ebe4", width: "50%", animation: "shimmer 1.5s infinite", backgroundSize: "200% 100%" }} />
          </div>
        </div>
        <div style={{ height: 10, borderRadius: 4, background: "#f0ebe4", width: "30%", marginBottom: 8, animation: "shimmer 1.5s infinite", backgroundSize: "200% 100%" }} />
        <div style={{ display: "flex", gap: 6, flexWrap: "wrap" }}>
          {[1, 2, 3].map((n) => <div key={n} style={{ height: 22, width: 72, borderRadius: 99, background: "#f0ebe4", animation: "shimmer 1.5s infinite", backgroundSize: "200% 100%" }} />)}
        </div>
      </div>
    );
  }

  if (state.status === "error") {
    return (
      <div style={{
        border: "1px solid #fca5a5",
        borderRadius: 10,
        padding: "1rem",
        background: "#fef2f2",
        color: "#dc2626",
        fontSize: 13,
      }}>
        Failed to load profile: {state.message}
      </div>
    );
  }

  const { data } = state;
  const age = computeAge(data.dateOfBirth);

  return (
    <div style={{
      border: "1px solid #e5e7eb",
      borderRadius: 10,
      padding: "1rem",
      background: "#fff",
      boxShadow: "0 1px 3px rgba(0,0,0,0.04)",
    }}>
      {/* Header */}
      <div style={{ display: "flex", gap: "0.75rem", marginBottom: "0.75rem" }}>
        <PetPhotoDisplay petId={petId} size={64} />
        <div style={{ flex: 1, minWidth: 0 }}>
          <strong style={{ fontSize: 16 }}>{data.name}</strong>
          <div style={{ fontSize: 13, color: "#6b7280", marginTop: "0.15rem" }}>
            {data.breed ?? "Unknown breed"}
            {age && <span> · {age}</span>}
          </div>
          {data.weightKg != null && (
            <div style={{ fontSize: 12, color: "#6b7280" }}>{data.weightKg} kg</div>
          )}
        </div>
      </div>

      {/* Coat type */}
      {data.coatType && (
        <div style={{ marginBottom: "0.6rem" }}>
          <SectionLabel>COAT TYPE</SectionLabel>
          <span style={{ fontSize: 12, padding: "0.15rem 0.5rem", background: "#f0fdf4", color: "#166534", border: "1px solid #bbf7d0", borderRadius: 99, fontWeight: 500 }}>
            {data.coatType}
          </span>
        </div>
      )}

      {/* Temperament */}
      {(data.temperamentScore != null || data.temperamentFlags.length > 0) && (
        <div style={{ marginBottom: "0.6rem" }}>
          <SectionLabel>TEMPERAMENT</SectionLabel>
          <div style={{ display: "flex", alignItems: "center", gap: "0.5rem", flexWrap: "wrap" }}>
            {data.temperamentScore != null && <TemperamentDots score={data.temperamentScore} />}
            {data.temperamentFlags.map((flag) => (
              <span key={flag} style={{ fontSize: 11, padding: "0.1rem 0.4rem", background: "#f5f3ff", color: "#6d28d9", border: "1px solid #ddd6fe", borderRadius: 4, fontWeight: 500 }}>
                {flag}
              </span>
            ))}
          </div>
        </div>
      )}

      {/* Medical alerts — most prominent */}
      {data.medicalAlerts.length > 0 && (
        <div style={{ marginBottom: "0.6rem" }}>
          <SectionLabel>MEDICAL ALERTS</SectionLabel>
          <div style={{ display: "flex", flexWrap: "wrap", gap: "0.35rem" }}>
            {data.medicalAlerts.map((alert) => (
              <MedicalAlertBadge key={alert.id} alert={alert} />
            ))}
          </div>
        </div>
      )}

      {/* Preferred cuts */}
      {data.preferredCuts.length > 0 && (
        <div style={{ marginBottom: "0.6rem" }}>
          <SectionLabel>PREFERRED CUTS</SectionLabel>
          <div style={{ display: "flex", flexWrap: "wrap", gap: "0.35rem" }}>
            {data.preferredCuts.map((cut) => (
              <span key={cut} style={{ fontSize: 11, padding: "0.15rem 0.45rem", background: "#f8fafc", color: "#374151", border: "1px solid #e2e8f0", borderRadius: 4 }}>
                {cut}
              </span>
            ))}
          </div>
        </div>
      )}

      {/* Recent visits */}
      {data.recentVisits.length > 0 && (
        <div style={{ marginBottom: "0.6rem" }}>
          <SectionLabel>RECENT VISITS</SectionLabel>
          {data.recentVisits.slice(0, 3).map((log) => (
            <div key={log.id} style={{ fontSize: 12, color: "#374151", marginBottom: "0.2rem", borderLeft: "2px solid #e2e8f0", paddingLeft: "0.4rem" }}>
              <span style={{ color: "#6b7280" }}>{new Date(log.groomedAt).toLocaleDateString()}</span>
              {log.cutStyle && <span> · {log.cutStyle}</span>}
              {log.staffId && <span> ·</span>}
            </div>
          ))}
        </div>
      )}

      {/* Next appointment */}
      {data.nextAppointment && (
        <div>
          <SectionLabel>NEXT APPOINTMENT</SectionLabel>
          <div style={{ fontSize: 12, color: "#374151" }}>
            {new Date(data.nextAppointment.startTime).toLocaleDateString()} — {data.nextAppointment.serviceName}
          </div>
        </div>
      )}
    </div>
  );
}