import { useEffect, useRef, useState } from "react";

/**
 * A pinned note on a phone.
 *
 * There is no margin to write in: a page narrow enough to read on a phone leaves
 * no white space beside it, and stealing 200px for a column would make the
 * document itself unreadable. So the note comes up from the bottom instead —
 * over the page rather than beside it, but only while it is being read or
 * written, and within reach of a thumb rather than at the top of the screen.
 *
 * The page stays visible above it, so the passage the note is about is still
 * there while writing about it.
 */
export function PdfNoteSheet({ T, note, number, onChange, onClose, onRemove }) {
  const [draft, setDraft] = useState(note.text);
  const areaRef = useRef(null);

  useEffect(() => setDraft(note.text), [note.id]);

  const commit = () => {
    if (draft !== note.text) onChange(draft);
  };
  const close = () => {
    commit();
    onClose();
  };

  useEffect(() => {
    const onKey = (e) => {
      if (e.key === "Escape") close();
    };
    window.addEventListener("keydown", onKey);
    return () => window.removeEventListener("keydown", onKey);
  });

  return (
    <div
      data-pin-sheet={note.id}
      style={{
        position: "absolute",
        left: 0,
        right: 0,
        bottom: 0,
        zIndex: 60,
        background: T.bar,
        borderTop: `1px solid ${T.border}`,
        borderRadius: "14px 14px 0 0",
        boxShadow: "0 -8px 26px rgba(0,0,0,.3)",
        padding: "10px 12px calc(10px + env(safe-area-inset-bottom))",
      }}
    >
      <div style={{ display: "flex", alignItems: "center", gap: 8, marginBottom: 8 }}>
        <span
          style={{
            width: 20,
            height: 20,
            borderRadius: "50%",
            background: T.accent,
            color: "#fff",
            fontSize: 11,
            fontWeight: 700,
            display: "flex",
            alignItems: "center",
            justifyContent: "center",
            flexShrink: 0,
          }}
        >
          {number}
        </span>
        <span style={{ fontSize: 11.5, color: T.muted, flex: 1 }}>Note on this passage</span>
        <button
          onClick={onRemove}
          data-pin-remove
          style={{
            border: "none",
            background: "transparent",
            color: T.danger,
            cursor: "pointer",
            fontSize: 11.5,
            padding: 0,
          }}
        >
          Remove
        </button>
      </div>

      <textarea
        ref={areaRef}
        autoFocus
        value={draft}
        onChange={(e) => setDraft(e.target.value)}
        onKeyDown={(e) => e.stopPropagation()}
        aria-label="Pinned note"
        placeholder="Note on this passage…"
        rows={3}
        style={{
          width: "100%",
          resize: "none",
          border: `1px solid ${T.border}`,
          borderRadius: 8,
          background: "transparent",
          color: T.text,
          fontSize: 13,
          lineHeight: 1.5,
          padding: "8px 10px",
          outline: "none",
          fontFamily: "inherit",
        }}
      />

      <button
        onClick={close}
        style={{
          width: "100%",
          marginTop: 8,
          border: "none",
          background: T.accent,
          color: "#fff",
          borderRadius: 10,
          cursor: "pointer",
          fontSize: 13,
          fontWeight: 600,
          padding: "9px 0",
        }}
      >
        Done
      </button>
    </div>
  );
}