/* Admin-Dashboard des Kundenportals (Ticketsystem-Mitarbeiter). */

async function api(path, options = {}) {
  const response = await fetch(path, {
    credentials: 'same-origin',
    headers: { 'Content-Type': 'application/json', ...(options.headers || {}) },
    ...options,
  })
  const data = await response.json().catch(() => ({}))
  if (!response.ok) {
    const err = new Error(data.error || `Fehler ${response.status}`)
    err.status = response.status
    throw err
  }
  return data
}

function escapeHtml(str) {
  return String(str ?? '')
    .replace(/&/g, '&')
    .replace(/</g, '&lt;')
    .replace(/>/g, '&gt;')
    .replace(/"/g, '&quot;')
}

function fmtDate(value) {
  if (!value) return '–'
  const d = new Date(value)
  if (Number.isNaN(d.getTime())) return escapeHtml(value)
  return d.toLocaleDateString('de-DE', { day: '2-digit', month: '2-digit', year: 'numeric' })
}

function fmtDateTime(value) {
  if (!value) return '–'
  const d = new Date(value)
  if (Number.isNaN(d.getTime())) return escapeHtml(value)
  return d.toLocaleString('de-DE', { day: '2-digit', month: '2-digit', year: '2-digit', hour: '2-digit', minute: '2-digit' })
}

function fmtEuro(value) {
  return Number(value || 0).toLocaleString('de-DE', { style: 'currency', currency: 'EUR' })
}

function stagePill(status) {
  const s = String(status || '').toLowerCase()
  if (s === 'lead') return '<span class="pill pill-warn">Lead</span>'
  if (s === 'lost') return '<span class="pill pill-muted">Abgesagt</span>'
  return '<span class="pill pill-ok">Fester Kunde</span>'
}

function statusPill(project) {
  const s = String(project.provisioningStatus || project.status || '').toLowerCase()
  if (['ready', 'deployed'].includes(s)) return '<span class="pill pill-ok">deployed</span>'
  if (s.includes('fail')) return '<span class="pill pill-red">Fehler</span>'
  if (!project.subdomain) return '<span class="pill pill-muted">ohne Website</span>'
  return `<span class="pill pill-warn">${escapeHtml(project.status || 'pending')}</span>`
}

function showError(message) {
  const el = document.getElementById('admin-error')
  el.textContent = message
  el.classList.remove('hidden')
}

/* ------------------------------------------------------------ Übersicht --- */
async function loadOverview() {
  const grid = document.getElementById('stat-grid')
  const logins = document.getElementById('recent-logins')
  const recent = document.getElementById('recent-projects')
  try {
    const o = await api('/api/portal-admin/overview')
    grid.innerHTML = [
      { num: o.projects.total, lbl: 'Projekte gesamt' },
      { num: o.projects.deployed, lbl: 'Websites online' },
      { num: o.projects.withoutWebsite, lbl: 'Projekte ohne Website' },
      { num: o.customers.total, lbl: 'Kunden gesamt' },
      { num: o.customers.leads, lbl: 'Leads' },
      { num: o.customers.portalEnabled, lbl: 'Portal-Zugänge' },
    ].map((s) => `<div class="stat-tile"><span class="num">${s.num}</span><span class="lbl">${s.lbl}</span></div>`).join('')

    logins.innerHTML = o.recentLogins.length
      ? o.recentLogins.map((l) => `<li>${escapeHtml(l.customerName)} <span class="muted">– ${fmtDateTime(l.lastLoginAt)}</span></li>`).join('')
      : '<li class="muted">Noch keine Portal-Logins.</li>'

    recent.innerHTML = o.recentProjects.length
      ? o.recentProjects.map((p) => `<li>${escapeHtml(p.projectName)}${p.customerName ? ` <span class="muted">(${escapeHtml(p.customerName)})</span>` : ''} <span class="muted">– ${fmtDateTime(p.updatedAt)}</span></li>`).join('')
      : '<li class="muted">Keine Projekte.</li>'
  } catch (err) {
    grid.innerHTML = ''
    showError(err.message)
  }
}

/* ------------------------------------------------------------- Projekte --- */
let projectSearchTimer = null

async function loadProjects(search = '') {
  const tbody = document.getElementById('project-rows')
  try {
    const { projects } = await api(`/api/portal-admin/projects?search=${encodeURIComponent(search)}`)
    if (!projects.length) {
      tbody.innerHTML = '<tr><td colspan="6" class="muted">Keine Projekte gefunden.</td></tr>'
      return
    }
    tbody.innerHTML = projects.map((p) => `
      <tr>
        <td>${escapeHtml(p.projectName || p.repoFullName || '–')}</td>
        <td>${p.subdomain ? escapeHtml(p.subdomain) : '<span class="muted">–</span>'}</td>
        <td>${p.customerName ? escapeHtml(p.customerName) : '<span class="muted">–</span>'}</td>
        <td>${statusPill(p)}</td>
        <td>${p.projectType === 'repo' ? 'Repo' : 'Website'}</td>
        <td>
          ${p.previewUrl ? `<a class="plain" href="${escapeHtml(p.previewUrl)}" target="_blank" rel="noreferrer">Vorschau</a>` : ''}
          ${p.giteaRepoUrl ? ` · <a class="plain" href="${escapeHtml(p.giteaRepoUrl)}" target="_blank" rel="noreferrer">Gitea</a>` : ''}
        </td>
      </tr>`).join('')
  } catch (err) {
    tbody.innerHTML = `<tr><td colspan="6" class="error">${escapeHtml(err.message)}</td></tr>`
  }
}

/* --------------------------------------------------------------- Kunden --- */
let customerSearchTimer = null

async function saveCustomerCode(customerId, btn) {
  const input = document.querySelector(`input[data-code-for="${customerId}"]`)
  if (!input) return
  btn.disabled = true
  try {
    await api(`/api/portal-admin/customers/${encodeURIComponent(customerId)}`, {
      method: 'PATCH',
      body: JSON.stringify({ code: input.value }),
    })
    btn.textContent = '✓ Gespeichert'
    setTimeout(() => { btn.textContent = '✓'; btn.disabled = false }, 1200)
  } catch (err) {
    btn.disabled = false
    alert('Kundennummer konnte nicht gespeichert werden: ' + err.message)
  }
}

async function viewAsCustomer(customerId) {
  try {
    await api(`/api/portal-admin/view-as/${encodeURIComponent(customerId)}`, { method: 'POST' })
    window.location.href = '/dashboard.html'
  } catch (err) {
    alert('Ansicht konnte nicht gewechselt werden: ' + err.message)
  }
}

function renderActivity(tickets) {
  if (!tickets.length) return '<p class="muted">Keine Tickets für diesen Kunden.</p>'
  return tickets.map((t) => `
    <div class="detail-box">
      <strong>${escapeHtml(t.woid ? `#${t.woid}` : '')} ${escapeHtml(t.topic || '–')}</strong>
      <span class="pill pill-muted">${escapeHtml(t.status || '–')}</span>
      <span class="muted">${escapeHtml(t.type || '')} · ${fmtDate(t.createdAt)}</span>
      ${(t.worksheets || []).map((w) => `
        <div class="ws-line">→ ${fmtDate(w.date)} ${escapeHtml(w.employeeName)} (${escapeHtml(w.serviceType || '–')}${w.totalTime ? `, ${escapeHtml(w.totalTime)}` : ''}): ${escapeHtml((w.details || '').slice(0, 160))}</div>
      `).join('')}
    </div>`).join('')
}

function renderInvoices(data) {
  if (!data.linked) return '<p class="muted">Kunde ist nicht mit InvoiceNinja verknüpft.</p>'
  if (!data.invoices.length) return '<p class="muted">Keine Rechnungen vorhanden.</p>'
  return `<table class="admin-table"><thead><tr><th>Nr.</th><th>Datum</th><th>Betrag</th><th>Offen</th><th>Status</th><th></th></tr></thead><tbody>
    ${data.invoices.map((i) => `
      <tr>
        <td>${escapeHtml(i.number)}</td>
        <td>${fmtDate(i.date)}</td>
        <td>${fmtEuro(i.amount)}</td>
        <td>${fmtEuro(i.balance)}</td>
        <td><span class="pill ${i.overdue ? 'pill-red' : i.statusId === 4 ? 'pill-ok' : 'pill-warn'}">${escapeHtml(i.status)}</span></td>
        <td>${i.portalUrl ? `<a class="plain" href="${escapeHtml(i.portalUrl)}" target="_blank" rel="noreferrer">Ansehen</a>` : ''}</td>
      </tr>`).join('')}
  </tbody></table>`
}

async function toggleCustomerDetail(customerId, kind, cell) {
  const existing = document.getElementById(`detail-${customerId}`)
  if (existing) {
    const wasKind = existing.dataset.kind
    existing.remove()
    if (wasKind === kind) return
  }

  const row = document.querySelector(`tr[data-customer-row="${customerId}"]`)
  if (!row) return
  const tr = document.createElement('tr')
  tr.id = `detail-${customerId}`
  tr.dataset.kind = kind
  tr.className = 'detail-row'
  tr.innerHTML = `<td colspan="7"><div class="detail-box muted">Lade…</div></td>`
  row.after(tr)

  try {
    if (kind === 'activity') {
      const { tickets } = await api(`/api/portal-admin/customers/${encodeURIComponent(customerId)}/activity`)
      tr.innerHTML = `<td colspan="7"><h4>Tickets &amp; Arbeiten</h4>${renderActivity(tickets)}</td>`
    } else {
      const data = await api(`/api/portal-admin/customers/${encodeURIComponent(customerId)}/invoices`)
      tr.innerHTML = `<td colspan="7"><h4>Rechnungen</h4>${renderInvoices(data)}</td>`
    }
  } catch (err) {
    tr.innerHTML = `<td colspan="7"><span class="error">${escapeHtml(err.message)}</span></td>`
  }
}

async function loadCustomers(search = '') {
  const tbody = document.getElementById('customer-rows')
  try {
    const { customers } = await api(`/api/portal-admin/customers?search=${encodeURIComponent(search)}`)
    if (!customers.length) {
      tbody.innerHTML = '<tr><td colspan="7" class="muted">Keine Kunden gefunden.</td></tr>'
      return
    }
    tbody.innerHTML = customers.map((c) => `
      <tr data-customer-row="${escapeHtml(c.id)}">
        <td style="white-space:nowrap">
          <input class="code-input" data-code-for="${escapeHtml(c.id)}" value="${escapeHtml(c.code)}" placeholder="–">
          <button class="mini-btn" data-save-code="${escapeHtml(c.id)}" title="Kundennummer speichern">✓</button>
        </td>
        <td>
          <strong>${escapeHtml(c.name)}</strong><br>
          <span class="muted">${escapeHtml(c.email || '–')}</span>
        </td>
        <td>${stagePill(c.customerStatus)}</td>
        <td>${c.portalAccessEnabled ? '<span class="pill pill-ok">aktiv</span>' : '<span class="pill pill-muted">kein Zugang</span>'}</td>
        <td>${fmtDateTime(c.lastLoginAt)}</td>
        <td>${c.projectCount}</td>
        <td style="white-space:nowrap">
          <button class="mini-btn primary" data-view-as="${escapeHtml(c.id)}">Als Kunde ansehen</button>
          <button class="mini-btn" data-activity="${escapeHtml(c.id)}">Arbeiten</button>
          <button class="mini-btn" data-invoices="${escapeHtml(c.id)}"${c.invoiceNinjaLinked ? '' : ' title="Nicht mit InvoiceNinja verknüpft"'}>Rechnungen</button>
        </td>
      </tr>`).join('')

    tbody.querySelectorAll('[data-save-code]').forEach((btn) =>
      btn.addEventListener('click', () => saveCustomerCode(btn.dataset.saveCode, btn)))
    tbody.querySelectorAll('[data-view-as]').forEach((btn) =>
      btn.addEventListener('click', () => viewAsCustomer(btn.dataset.viewAs)))
    tbody.querySelectorAll('[data-activity]').forEach((btn) =>
      btn.addEventListener('click', () => toggleCustomerDetail(btn.dataset.activity, 'activity')))
    tbody.querySelectorAll('[data-invoices]').forEach((btn) =>
      btn.addEventListener('click', () => toggleCustomerDetail(btn.dataset.invoices, 'invoices')))
  } catch (err) {
    tbody.innerHTML = `<tr><td colspan="7" class="error">${escapeHtml(err.message)}</td></tr>`
  }
}

/* ----------------------------------------------------------------- Chat --- */
const adminChat = {
  activeCustomerId: '',
  activeCustomerName: '',
  lastCreatedAt: '',
  threadTimer: null,
}

function updateAdminChatBadge(unread) {
  const badge = document.getElementById('admin-chat-badge')
  if (!badge) return
  if (unread > 0) {
    badge.textContent = unread
    badge.classList.remove('hidden')
  } else {
    badge.classList.add('hidden')
  }
}

async function pollAdminChatBadge() {
  if (document.hidden) return
  try {
    const { unread } = await api('/api/portal-admin/chats/unread-count')
    updateAdminChatBadge(unread)
  } catch {
    /* ignore */
  }
}

async function loadChatList() {
  const list = document.getElementById('admin-chat-list')
  try {
    const { chats } = await api('/api/portal-admin/chats')
    if (!chats.length) {
      list.innerHTML = '<div class="chat-list-item"><span class="muted">Noch keine Unterhaltungen.</span></div>'
      return
    }
    list.innerHTML = chats.map((c) => `
      <div class="chat-list-item${c.customerId === adminChat.activeCustomerId ? ' active' : ''}" data-chat-customer="${escapeHtml(c.customerId)}" data-chat-name="${escapeHtml(c.customerName)}">
        <div style="display:flex;justify-content:space-between;align-items:center;gap:8px">
          <strong>${escapeHtml(c.customerName)}</strong>
          ${c.unreadFromCustomer ? `<span class="badge-pill">${c.unreadFromCustomer}</span>` : ''}
        </div>
        <div class="last">${c.lastSender === 'admin' ? 'Du: ' : ''}${escapeHtml(c.lastText)}</div>
        <div class="last">${fmtDateTime(c.lastAt)}</div>
      </div>`).join('')
    list.querySelectorAll('[data-chat-customer]').forEach((el) =>
      el.addEventListener('click', () => openChatThread(el.dataset.chatCustomer, el.dataset.chatName)))
  } catch (err) {
    list.innerHTML = `<div class="chat-list-item"><span class="error">${escapeHtml(err.message)}</span></div>`
  }
}

function appendAdminChatMessages(messages) {
  const box = document.getElementById('admin-chat-messages')
  if (!box || !messages.length) return
  for (const msg of messages) {
    const div = document.createElement('div')
    div.className = `chat-bubble ${msg.sender === 'admin' ? 'mine' : 'theirs'}`
    div.innerHTML = `${escapeHtml(msg.text)}<span class="chat-meta">${msg.sender === 'admin' ? escapeHtml(msg.senderName || 'Admin') : escapeHtml(adminChat.activeCustomerName)} · ${fmtDateTime(msg.createdAt)}</span>`
    box.appendChild(div)
    if (msg.createdAt > adminChat.lastCreatedAt) adminChat.lastCreatedAt = msg.createdAt
  }
  box.scrollTop = box.scrollHeight
}

async function pollAdminThread() {
  if (!adminChat.activeCustomerId || document.hidden) return
  try {
    const q = adminChat.lastCreatedAt ? `?since=${encodeURIComponent(adminChat.lastCreatedAt)}` : ''
    const { messages } = await api(`/api/portal-admin/chats/${encodeURIComponent(adminChat.activeCustomerId)}/messages${q}`)
    if (messages.length) {
      appendAdminChatMessages(messages)
      await api(`/api/portal-admin/chats/${encodeURIComponent(adminChat.activeCustomerId)}/read`, { method: 'POST' }).catch(() => {})
    }
  } catch {
    /* naechster Poll */
  }
}

async function sendAdminChatMessage() {
  const input = document.getElementById('admin-chat-input')
  const btn = document.getElementById('admin-chat-send')
  const text = input.value.trim()
  if (!text || !adminChat.activeCustomerId) return
  btn.disabled = true
  try {
    const { message } = await api(`/api/portal-admin/chats/${encodeURIComponent(adminChat.activeCustomerId)}/messages`, {
      method: 'POST',
      body: JSON.stringify({ text }),
    })
    input.value = ''
    appendAdminChatMessages([message])
    loadChatList()
  } catch (err) {
    alert('Nachricht konnte nicht gesendet werden: ' + err.message)
  } finally {
    btn.disabled = false
    input.focus()
  }
}

async function openChatThread(customerId, customerName) {
  adminChat.activeCustomerId = customerId
  adminChat.activeCustomerName = customerName || 'Kunde'
  adminChat.lastCreatedAt = ''

  const thread = document.getElementById('admin-chat-thread')
  thread.innerHTML = `
    <div style="margin-bottom:8px"><strong>${escapeHtml(adminChat.activeCustomerName)}</strong></div>
    <div class="chat-messages" id="admin-chat-messages"></div>
    <div class="chat-input-row">
      <textarea id="admin-chat-input" maxlength="2000" placeholder="Antwort an ${escapeHtml(adminChat.activeCustomerName)}…"></textarea>
      <button type="button" class="mini-btn primary" id="admin-chat-send" style="padding:12px 18px">Senden</button>
    </div>`

  document.getElementById('admin-chat-send').addEventListener('click', sendAdminChatMessage)
  document.getElementById('admin-chat-input').addEventListener('keydown', (e) => {
    if (e.key === 'Enter' && !e.shiftKey) {
      e.preventDefault()
      sendAdminChatMessage()
    }
  })

  try {
    const { messages } = await api(`/api/portal-admin/chats/${encodeURIComponent(customerId)}/messages`)
    appendAdminChatMessages(messages)
    await api(`/api/portal-admin/chats/${encodeURIComponent(customerId)}/read`, { method: 'POST' }).catch(() => {})
    updateAdminChatBadge(0)
    pollAdminChatBadge()
    loadChatList()
  } catch (err) {
    document.getElementById('admin-chat-messages').innerHTML = `<span class="error">${escapeHtml(err.message)}</span>`
  }

  clearInterval(adminChat.threadTimer)
  adminChat.threadTimer = setInterval(pollAdminThread, 15000)
}

/* ----------------------------------------------------------------- Init --- */
async function initAdminPage() {
  document.getElementById('logout-btn')?.addEventListener('click', async () => {
    await api('/api/auth/logout', { method: 'POST' }).catch(() => {})
    window.location.href = '/login.html'
  })

  try {
    const me = await api('/api/auth/me')
    if (!me.authenticated || me.role !== 'admin') {
      window.location.href = '/login.html'
      return
    }
    if (me.viewAs) {
      // Admin ist gerade in der Kundenansicht -> zurückholen
      await api('/api/portal-admin/exit-view-as', { method: 'POST' }).catch(() => {})
    }
    document.getElementById('admin-meta').textContent =
      `${me.admin?.name || 'Admin'} (${me.admin?.email || ''})`
  } catch {
    window.location.href = '/login.html'
    return
  }

  let chatListLoaded = false
  document.querySelectorAll('.admin-tab').forEach((tab) => {
    tab.addEventListener('click', () => {
      document.querySelectorAll('.admin-tab').forEach((t) => t.classList.remove('active'))
      document.querySelectorAll('.admin-section').forEach((s) => s.classList.remove('active'))
      tab.classList.add('active')
      document.getElementById(`tab-${tab.dataset.tab}`).classList.add('active')
      if (tab.dataset.tab === 'chat' && !chatListLoaded) {
        chatListLoaded = true
        loadChatList()
      }
    })
  })

  document.getElementById('project-search')?.addEventListener('input', (e) => {
    clearTimeout(projectSearchTimer)
    projectSearchTimer = setTimeout(() => loadProjects(e.target.value.trim()), 250)
  })
  document.getElementById('customer-search')?.addEventListener('input', (e) => {
    clearTimeout(customerSearchTimer)
    customerSearchTimer = setTimeout(() => loadCustomers(e.target.value.trim()), 250)
  })

  loadOverview()
  loadProjects()
  loadCustomers()

  // Chat-Badge global pollen
  pollAdminChatBadge()
  setInterval(pollAdminChatBadge, 60000)
}

window.initAdminPage = initAdminPage