// Uplink form: choose a binary file (or type hex) and transmit it.

import { api } from './api.js';
import { h, clear, toast } from './dom.js';
import { hexView, parseHex } from './hexview.js';

export function uplinkView(ctx) {
  const ship = ctx.ship;
  const limit = ctx.state.info?.comm_bytes ?? 1024;
  const open = ship && (ship.status === 'launching' || ship.status === 'active');

  let bytes = null;
  let label = '';

  const preview = h('div', { class: 'uplink-preview' });
  const meter = h('div', { class: 'meter', role: 'meter', 'aria-valuemin': '0', 'aria-valuemax': String(limit), 'aria-label': 'Message size' }, h('div', { class: 'fill' }));
  const sizeText = h('p', { class: 'dim' }, `NO MESSAGE LOADED. LIMIT ${limit} BYTES.`);
  const err = h('p', { class: 'form-error', role: 'alert' });
  const send = h('button', { class: 'btn primary', type: 'button', disabled: true }, ship ? `TRANSMIT TO SHIP #${ship.id}` : 'NO SHIP');

  function set(b, from) {
    bytes = b;
    label = from;
    err.textContent = '';
    const over = b.length > limit;
    meter.classList.toggle('over', over);
    meter.setAttribute('aria-valuenow', String(b.length));
    meter.querySelector('.fill').style.setProperty('width', `${Math.min(100, (b.length / limit) * 100)}%`);
    sizeText.textContent = `${from}: ${b.length} BYTES OF ${limit}${over ? ' -- TOO LARGE' : ''}`;
    if (over) err.textContent = `MESSAGE EXCEEDS THE ${limit}-BYTE LINK. REMOVE ${b.length - limit} BYTES.`;
    else if (b.length === 0) err.textContent = 'MESSAGE IS EMPTY.';
    send.disabled = !open || over || b.length === 0;
    clear(preview);
    if (b.length) {
      preview.append(hexView(b, { rows: 8 }).el);
      if (b.length > 128) preview.append(h('p', { class: 'hint' }, `SHOWING THE FIRST 128 OF ${b.length} BYTES.`));
    }
  }

  // ---- file chooser / drop zone ------------------------------------------
  const file = h('input', { type: 'file', id: 'uplink-file', class: 'sr-only' });
  const drop = h('label', { class: `drop ${open ? '' : 'disabled'}`, for: 'uplink-file' },
    h('span', { class: 'drop-big' }, 'DROP A BINARY FILE HERE'),
    h('span', { class: 'dim' }, 'or click to choose one'),
  );
  file.disabled = !open;
  const takeFile = async (f) => {
    if (!f) return;
    if (f.size > 1 << 20) { err.textContent = 'THAT FILE IS FAR TOO LARGE FOR THE LINK.'; return; }
    set(new Uint8Array(await f.arrayBuffer()), f.name.toUpperCase());
  };
  file.addEventListener('change', () => takeFile(file.files[0]));
  for (const ev of ['dragenter', 'dragover']) drop.addEventListener(ev, (e) => { e.preventDefault(); if (open) drop.classList.add('over'); });
  for (const ev of ['dragleave', 'drop']) drop.addEventListener(ev, () => drop.classList.remove('over'));
  drop.addEventListener('drop', (e) => { e.preventDefault(); if (open) takeFile(e.dataTransfer.files[0]); });

  // ---- hex entry ---------------------------------------------------------
  const hexIn = h('textarea', { id: 'hex-in', rows: '3', spellcheck: 'false', placeholder: 'DE AD BE EF 00 01 ...', disabled: !open, 'aria-label': 'Message as hexadecimal' });
  const useHex = h('button', { class: 'btn small', type: 'button', disabled: !open, onclick: () => {
    try { set(parseHex(hexIn.value), 'HEX ENTRY'); } catch (e) { err.textContent = `HEX ERROR: ${e.message}`; }
  } }, 'USE HEX');

  send.addEventListener('click', async () => {
    send.disabled = true;
    try {
      await api.setUplink(ship.id, bytes);
      toast(`UPLINK QUEUED FOR SHIP #${ship.id}: ${bytes.length} BYTES. DELIVERED AT THE START OF THE NEXT RUN.`);
    } catch (e) {
      err.textContent = `TRANSMISSION FAILED: ${e.message}`;
      send.disabled = false;
    }
  });

  const status = !ship
    ? 'YOU HAVE NO SHIP.'
    : open
      ? `TARGET: SHIP #${ship.id}. A NEW UPLINK REPLACES ONE ALREADY QUEUED.`
      : `SHIP #${ship.id} IS ${ship.status.toUpperCase()}. UPLINKS CAN ONLY BE SENT TO SHIPS THAT ARE LAUNCHING OR IN THE BELT.`;

  return h('div', { class: 'grid-2 uplink-grid' },
    h('section', { class: 'panel' },
      h('div', { class: 'panel-title' }, 'UPLINK TRANSMITTER'),
      h('div', { class: 'panel-body stack' },
        h('p', { class: open ? 'hint' : 'warn' }, status),
        drop, file,
        h('label', { for: 'hex-in' }, 'OR ENTER HEX'),
        hexIn,
        h('div', null, useHex),
        meter, sizeText, err,
        h('div', null, send),
      ),
    ),
    h('section', { class: 'panel' },
      h('div', { class: 'panel-title' }, 'OUTGOING MESSAGE'),
      h('div', { class: 'panel-body' },
        preview,
        h('p', { class: 'hint' }, 'THE MESSAGE IS OPAQUE BYTES. YOUR SHIP\'S PROGRAM DECIDES WHAT IT MEANS. IT ARRIVES IN THE UPLINK BUFFER (RAM 0-1023) BEFORE THE FIRST TICK OF THE NEXT DAILY RUN.'),
      ),
    ),
  );
}