// SQLite editor of the file manager: the agent opens the database and runs
// the queries, so a database in use keeps its locks. Tables and views in
// tabs, rows a page at a time; a click on a value edits it (Enter saves,
// Esc cancels, Shift+Enter a new line, the ∅ button makes it NULL). Rows are
// added and deleted, and a tab runs any SQL.
(function () {
  'use strict';
  var PAGE = 200;
  var esc = function (s) { return String(s).replace(/[&<>"]/g, function (c) { return {'&': '&amp;', '<': '&lt;', '>': '&gt;', '"': '&quot;'}[c]; }); };

  function cellHTML(c) {
    if (c.t === 'n') return '<i class="dbx-null">NULL</i>';
    if (c.t === 'b') return '<i class="dbx-null">BLOB ' + esc(c.v) + ' Б</i>';
    var v = c.v || '';
    return esc(v.length > 300 ? v.slice(0, 300) + '…' : v);
  }
  // The type a typed value goes as: what the value was, or what the column
  // is declared as, when the text fits it.
  function typeFor(text, was, decl) {
    var d = (decl || '').toUpperCase();
    var int = /^\s*-?\d+\s*$/.test(text), num = text.trim() !== '' && isFinite(Number(text));
    if (was === 'i' || (was !== 's' && /INT/.test(d))) return int ? 'i' : num ? 'r' : 's';
    if (was === 'r' || (was !== 's' && /REAL|FLOA|DOUB|NUM|DEC/.test(d))) return num ? 'r' : 's';
    return 's';
  }

  function open(box, path, call, toast) {
    var S = {tables: [], cur: null, offset: 0, data: null, sel: new Set()};
    box.innerHTML =
      '<div class="dbx">' +
      '<div class="dbx-tabs" role="tablist"></div>' +
      '<div class="dbx-tools">' +
      '  <span class="muted dbx-info"></span>' +
      '  <span class="dbx-pager"><button type="button" class="btn ghost small icon dbx-prev" title="Назад" aria-label="Назад">‹</button>' +
      '  <span class="muted dbx-range"></span><button type="button" class="btn ghost small icon dbx-next" title="Дальше" aria-label="Дальше">›</button></span>' +
      '  <span class="dbx-sp"></span>' +
      '  <button type="button" class="btn ghost small dbx-add">+ Строка</button>' +
      '  <button type="button" class="btn danger small dbx-del" disabled>Удалить</button>' +
      '</div>' +
      '<div class="dbx-grid"></div>' +
      '<div class="dbx-sql" hidden>' +
      '  <textarea class="dbx-q" spellcheck="false" placeholder="SELECT * FROM … - Ctrl+Enter выполнить"></textarea>' +
      '  <div class="dbx-sqlbar"><button type="button" class="dbx-run">Выполнить</button><span class="muted dbx-sqlmsg"></span></div>' +
      '  <div class="dbx-sqlres"></div>' +
      '</div>' +
      '</div>';
    var $ = function (s) { return box.querySelector(s); };

    function busy(on) { box.querySelector('.dbx').classList.toggle('busy', on); }
    function req(op, args) {
      args.path = path;
      busy(true);
      return call(op, args).then(function (r) { busy(false); return r; }, function (e) { busy(false); throw e; });
    }

    function tabs() {
      var t = $('.dbx-tabs');
      t.innerHTML = '';
      S.tables.forEach(function (x) {
        var b = document.createElement('button');
        b.type = 'button';
        b.textContent = x.name;
        if (x.type === 'view') b.title = 'представление - только чтение';
        b.className = x.name === S.cur ? 'on' : '';
        b.onclick = function () { show(x.name, 0); };
        t.appendChild(b);
      });
      var q = document.createElement('button');
      q.type = 'button';
      q.textContent = 'SQL';
      q.className = 'dbx-sqltab' + (S.cur === null ? ' on' : '');
      q.onclick = sqlTab;
      t.appendChild(q);
    }

    function show(name, offset) {
      S.cur = name; S.offset = offset; S.sel.clear();
      tabs();
      $('.dbx-sql').hidden = true;
      $('.dbx-grid').hidden = false;
      $('.dbx-tools').hidden = false;
      return req('db.rows', {table: name, offset: offset, limit: PAGE}).then(function (r) {
        if (!r.ok) { $('.dbx-grid').innerHTML = '<p class="dv-note">' + esc(r.error || 'ошибка') + '</p>'; return; }
        S.data = r.data;
        draw();
      });
    }

    function draw() {
      var d = S.data, t = d.table, editable = !!t.key;
      // An INTEGER PRIMARY KEY column already shows the rowid.
      var showRowid = t.key === 'rowid' && !t.alias;
      $('.dbx-info').textContent = d.total + ' ' + plural(d.total) + (t.type === 'view' ? ' · представление' : !editable ? ' · только чтение' : '');
      $('.dbx-range').textContent = d.rows.length ? (d.offset + 1) + '–' + (d.offset + d.rows.length) : '';
      $('.dbx-prev').disabled = d.offset <= 0;
      $('.dbx-next').disabled = d.offset + d.rows.length >= d.total;
      $('.dbx-pager').hidden = d.total <= PAGE;
      $('.dbx-add').hidden = t.type !== 'table';
      $('.dbx-del').hidden = !editable;
      selInfo();
      var h = '<table class="dbx-t"><thead><tr>' + (editable ? '<th class="dbx-ck"><input type="checkbox" class="dbx-all" aria-label="Выбрать все"></th>' : '') +
        (showRowid ? '<th class="dbx-k">rowid</th>' : '');
      t.columns.forEach(function (c) {
        h += '<th title="' + esc(c.type + (c.pk ? ' · ключ' : '') + (c.notnull ? ' · NOT NULL' : '')) + '">' + esc(c.name) +
          (c.type ? '<small>' + esc(c.type.toLowerCase()) + '</small>' : '') + '</th>';
      });
      h += '</tr></thead><tbody>';
      d.rows.forEach(function (row, i) {
        h += '<tr data-i="' + i + '">' + (editable ? '<td class="dbx-ck"><input type="checkbox" aria-label="Выбрать строку"></td>' : '') +
          (showRowid ? '<td class="dbx-k">' + esc(row.k) + '</td>' : '');
        row.v.forEach(function (c, j) {
          h += '<td data-j="' + j + '" class="' + (c.t === 'i' || c.t === 'r' ? 'num' : '') + (editable && c.t !== 'b' ? ' ed' : '') + '">' + cellHTML(c) + '</td>';
        });
        h += '</tr>';
      });
      h += '</tbody></table>';
      if (!d.rows.length) h += '<p class="dv-note">строк нет</p>';
      $('.dbx-grid').innerHTML = h;
      $('.dbx-grid').scrollTop = 0;
      fixWidths($('.dbx-grid table'));
    }
    // The columns keep the widths they first came out at, so a value being
    // edited does not move the table about.
    function fixWidths(table) {
      if (!table) return;
      var ths = table.querySelectorAll('thead th'), ws = [], sum = 0;
      ths.forEach(function (th) { var w = Math.ceil(th.getBoundingClientRect().width); ws.push(w); sum += w; });
      ths.forEach(function (th, i) { th.style.width = ws[i] + 'px'; });
      table.style.width = sum + 'px';
      table.style.tableLayout = 'fixed';
    }
    function plural(n) {
      var m10 = n % 10, m100 = n % 100;
      return m10 === 1 && m100 !== 11 ? 'строка' : m10 >= 2 && m10 <= 4 && (m100 < 12 || m100 > 14) ? 'строки' : 'строк';
    }
    function selInfo() {
      var b = $('.dbx-del');
      b.disabled = !S.sel.size;
      b.textContent = S.sel.size ? 'Удалить (' + S.sel.size + ')' : 'Удалить';
    }

    $('.dbx-prev').onclick = function () { show(S.cur, Math.max(0, S.offset - PAGE)); };
    $('.dbx-next').onclick = function () { show(S.cur, S.offset + PAGE); };

    // ---- selecting rows ----
    $('.dbx-grid').addEventListener('change', function (ev) {
      var el = ev.target;
      if (el.classList.contains('dbx-all')) {
        box.querySelectorAll('tbody .dbx-ck input').forEach(function (c, i) { c.checked = el.checked; el.checked ? S.sel.add(i) : S.sel.delete(i); });
      } else if (el.closest('tbody .dbx-ck')) {
        var i = +el.closest('tr').dataset.i;
        el.checked ? S.sel.add(i) : S.sel.delete(i);
      }
      selInfo();
    });

    // ---- editing a value ----
    var editing = null;
    $('.dbx-grid').addEventListener('click', function (ev) {
      var td = ev.target.closest('td.ed');
      if (!td || td.querySelector('textarea') || ev.target.closest('.dbx-edit')) return;
      edit(td);
    });
    function edit(td) {
      if (editing) finish(editing, true);
      var i = +td.parentNode.dataset.i, j = +td.dataset.j;
      var row = S.data.rows[i], cell = row.v[j], col = S.data.table.columns[j];
      var hgt = td.offsetHeight;
      td.classList.add('editing');
      td.innerHTML = '<div class="dbx-edit"><textarea spellcheck="false"></textarea><button type="button" class="dbx-nullb" title="Сделать NULL" aria-label="Сделать NULL">∅</button></div>';
      var ta = td.querySelector('textarea');
      ta.value = cell.t === 'n' ? '' : cell.v;
      ta.placeholder = cell.t === 'n' ? 'NULL' : '';
      ta.style.height = Math.max(hgt, 30) + 'px';
      ta.focus();
      ta.select();
      editing = {td: td, i: i, j: j, ta: ta, cell: cell, col: col, nul: false};
      ta.addEventListener('keydown', function (ev) {
        if (ev.key === 'Enter' && !ev.shiftKey) { ev.preventDefault(); finish(editing, true); }
        else if (ev.key === 'Escape') { ev.preventDefault(); ev.stopPropagation(); finish(editing, false); }
        else if (ev.key === 'Tab') {
          ev.preventDefault();
          var cur = editing, next = ev.shiftKey ? cur.td.previousElementSibling : cur.td.nextElementSibling;
          finish(cur, true);
          if (next && next.classList.contains('ed')) edit(next);
        }
      });
      ta.addEventListener('blur', function () { setTimeout(function () { if (editing && editing.ta === ta && document.activeElement !== td.querySelector('.dbx-nullb')) finish(editing, true); }, 120); });
      td.querySelector('.dbx-nullb').onmousedown = function (ev) { ev.preventDefault(); editing.nul = true; finish(editing, true); };
    }
    function finish(e, keep) {
      if (!e || editing !== e) return;
      editing = null;
      var text = e.ta.value, cell = e.cell;
      var value = e.nul ? {t: 'n'} : {t: typeFor(text, cell.t, e.col.type), v: text};
      var same = e.nul ? cell.t === 'n' : (cell.t !== 'n' || text !== '') && text === (cell.v || '') && (cell.t === value.t || cell.t === 's' || value.t === 's');
      if (cell.t === 'n' && !e.nul && text === '') same = true;
      e.td.classList.remove('editing');
      if (!keep || same) { e.td.innerHTML = cellHTML(cell); return; }
      e.td.innerHTML = cellHTML(value);
      e.td.classList.add('saving');
      req('db.set', {table: S.cur, key: S.data.rows[e.i].k, column: e.col.name, value: value}).then(function (r) {
        e.td.classList.remove('saving');
        if (!r.ok) {
          e.td.innerHTML = cellHTML(cell);
          flash(e.td, 'bad');
          toast(r.error || 'не сохранилось', true);
          return;
        }
        var got = r.data.value;
        S.data.rows[e.i].v[e.j] = got;
        // A changed key column moves the row's key too.
        if (r.data.key !== undefined) S.data.rows[e.i].k = r.data.key;
        e.td.innerHTML = cellHTML(got);
        e.td.className = (got.t === 'i' || got.t === 'r' ? 'num' : '') + ' ed';
        flash(e.td, 'ok');
      });
    }
    function flash(td, kind) {
      td.classList.remove('flash-ok', 'flash-bad');
      void td.offsetWidth;
      td.classList.add('flash-' + kind);
    }

    // ---- adding and deleting rows ----
    $('.dbx-add').onclick = function () {
      if (box.querySelector('tr.dbx-new')) return;
      var t = S.data.table, tbody = box.querySelector('.dbx-t tbody');
      var tr = document.createElement('tr');
      tr.className = 'dbx-new';
      var h = (t.key ? '<td class="dbx-ck"></td>' : '') + (t.key === 'rowid' && !t.alias ? '<td class="dbx-k">новая</td>' : '');
      t.columns.forEach(function (c) {
        h += '<td><input type="text" data-c="' + esc(c.name) + '" placeholder="' + esc(c.default ? 'по умолч.: ' + c.default : c.notnull ? 'обязательно' : 'NULL') + '"></td>';
      });
      tr.innerHTML = h;
      tbody.insertBefore(tr, tbody.firstChild);
      var bar = document.createElement('tr');
      bar.className = 'dbx-newbar';
      bar.innerHTML = '<td colspan="' + (t.columns.length + 2) + '"><button type="button" class="small dbx-addok">Добавить</button> <button type="button" class="btn ghost small dbx-addno">Отмена</button> <span class="muted">пустое поле - значение по умолчанию</span></td>';
      tbody.insertBefore(bar, tr.nextSibling);
      $('.dbx-grid').scrollTop = 0;
      tr.querySelector('input').focus();
      var done = function () { tr.remove(); bar.remove(); };
      bar.querySelector('.dbx-addno').onclick = done;
      var add = function () {
        var values = {};
        tr.querySelectorAll('input').forEach(function (inp) {
          if (inp.value === '') return;
          var c = t.columns.filter(function (x) { return x.name === inp.dataset.c; })[0];
          values[c.name] = {t: typeFor(inp.value, '', c.type), v: inp.value};
        });
        req('db.add', {table: S.cur, values: values}).then(function (r) {
          if (!r.ok) { toast(r.error || 'не добавилось', true); return; }
          toast('строка добавлена');
          var total = S.data.total + 1;
          show(S.cur, Math.floor((total - 1) / PAGE) * PAGE);
        });
      };
      bar.querySelector('.dbx-addok').onclick = add;
      tr.addEventListener('keydown', function (ev) {
        if (ev.key === 'Enter') { ev.preventDefault(); add(); }
        if (ev.key === 'Escape') { ev.preventDefault(); ev.stopPropagation(); done(); }
      });
    };
    $('.dbx-del').onclick = function () {
      var keys = [];
      S.sel.forEach(function (i) { keys.push(S.data.rows[i].k); });
      if (!keys.length || !confirm('Удалить строк: ' + keys.length + '?')) return;
      req('db.del', {table: S.cur, keys: keys}).then(function (r) {
        if (!r.ok) { toast(r.error || 'не удалилось', true); return; }
        toast('удалено строк: ' + r.data.deleted);
        show(S.cur, S.offset);
      });
    };

    // ---- SQL ----
    function sqlTab() {
      S.cur = null;
      tabs();
      $('.dbx-grid').hidden = true;
      $('.dbx-tools').hidden = true;
      $('.dbx-sql').hidden = false;
      $('.dbx-q').focus();
    }
    function run() {
      var q = $('.dbx-q').value;
      if (!q.trim()) return;
      $('.dbx-sqlmsg').textContent = '';
      req('db.sql', {sql: q}).then(function (r) {
        var out = $('.dbx-sqlres');
        if (!r.ok) { out.innerHTML = ''; $('.dbx-sqlmsg').textContent = r.error || 'ошибка'; $('.dbx-sqlmsg').className = 'dbx-sqlmsg bad'; return; }
        $('.dbx-sqlmsg').className = 'muted dbx-sqlmsg';
        var d = r.data;
        if (d.columns) {
          $('.dbx-sqlmsg').textContent = 'строк: ' + d.rows.length + (d.more ? ' (показаны первые 500)' : '');
          var h = '<table class="dbx-t"><thead><tr>' + d.columns.map(function (c) { return '<th>' + esc(c) + '</th>'; }).join('') + '</tr></thead><tbody>';
          d.rows.forEach(function (row) {
            h += '<tr>' + row.map(function (c) { return '<td class="' + (c.t === 'i' || c.t === 'r' ? 'num' : '') + '">' + cellHTML(c) + '</td>'; }).join('') + '</tr>';
          });
          out.innerHTML = h + '</tbody></table>';
        } else {
          out.innerHTML = '';
          $('.dbx-sqlmsg').textContent = 'готово · изменено строк: ' + d.changed;
          loadTables(true);
        }
      });
    }
    $('.dbx-run').onclick = run;
    $('.dbx-q').addEventListener('keydown', function (ev) {
      if (ev.key === 'Enter' && (ev.ctrlKey || ev.metaKey)) { ev.preventDefault(); run(); }
    });

    function loadTables(keep) {
      return req('db.tables', {}).then(function (r) {
        if (!r.ok) return r;
        S.tables = r.data.tables;
        if (keep) { tabs(); return r; }
        if (S.tables.length) show(S.tables[0].name, 0); else sqlTab();
        return r;
      });
    }
    return loadTables(false);
  }

  window.DBEdit = {open: open};
})();