/* teach - beheerpaneel (👥): gebruikers, klassen en scholen.
   Zichtbaar voor super (alles), admin (eigen school) en teacher (leerlingen). */
"use strict";
(function(){
  /* het beheerpaneel is een tabblad binnen Instellingen (settingsWrap/settingsModal),
     geen los venster meer - modal is alleen nog de content-container voor render() */
  const modal = document.getElementById("adminModal");
  const btn = document.getElementById("btnAdmin");
  let SCHOOLS = [], USERS = [], CLASSES = [], selSchool = null;
  /* resultaat van een laatste multireset (klas/school): blijft zichtbaar
     totdat de beheerder het venster zelf sluit, zodat wachtwoorden niet
     meteen weer verdwijnen na een reload() */
  let resetResults = null;
  /* actief tabblad, blijft behouden over her-renders heen (na elke actie) */
  let adminTab = "gebruikers";

  const esc = s => String(s ?? "").replace(/&/g,"&amp;").replace(/</g,"&lt;");
  const h = (tag, cls, text)=>{
    const el = document.createElement(tag);
    if(cls) el.className = cls;
    if(text != null) el.textContent = text;
    return el;
  };
  /* wachtwoorden/koppelcodes zijn maar eenmalig zichtbaar - een kopieerknop
     zorgt dat ze veilig bewaard kunnen worden voordat het scherm ververst */
  async function copyText(btn, text){
    try{ await navigator.clipboard.writeText(text); }
    catch(e){
      const ta = document.createElement("textarea");
      ta.value = text; ta.style.position = "fixed"; ta.style.opacity = "0";
      document.body.appendChild(ta); ta.select();
      try{ document.execCommand("copy"); }catch(_){ /* niets meer te doen */ }
      document.body.removeChild(ta);
    }
    const orig = btn.textContent;
    btn.textContent = "✅";
    setTimeout(()=>{ btn.textContent = orig; }, 1200);
  }
  function copyBtn(text, cls){
    const b = h("button", cls || "am-copy", "📋");
    b.type = "button";
    b.title = T("amCopy");
    b.addEventListener("click", e=>{ e.preventDefault(); if(text) copyText(b, text); });
    return b;
  }
  const msg = (t, copyValue) => {
    const m = modal.querySelector(".am-msg");
    if(!m) return;
    m.innerHTML = "";
    if(!t) return;
    m.appendChild(document.createTextNode(t));
    if(copyValue) m.appendChild(copyBtn(copyValue));
  };

  btn.addEventListener("click", async ()=>{
    if(!can("admin.access")) return;
    selSchool = currentUser.role==="super" ? (selSchool ?? "") : currentUser.schoolId;
    await reload();
    switchSettingsTab("admin");
  });
  document.addEventListener("userchange", ()=>{ if(!currentUser) resetResults = null; });

  async function reload(){
    try{
      if(currentUser.role==="super") SCHOOLS = await api("/schools");
      const q = currentUser.role==="super" && selSchool ? "?school="+selSchool : "";
      USERS = (await api("/admin/users"+q)).users;
      const cq = currentUser.role==="super" ? (selSchool ? "?school="+selSchool : "?school=0") : "";
      CLASSES = (await api("/admin/classes"+cq)).classes || [];
    }catch(e){ USERS = []; CLASSES = []; }
    render();
  }

  function classSel(current){
    const sel = h("select","am-sel");
    sel.appendChild(new Option(T("amNoClass"), ""));
    CLASSES.forEach(c=>sel.appendChild(new Option(c.name, c.id)));
    sel.value = current ?? "";
    return sel;
  }

  function userRow(u){
    const row = h("div","am-row");
    /* actieknoppen (kopieer/genereer/verwijder) samen in één groep, zodat
       ze op smalle schermen als blok rechts blijven staan i.p.v. los
       tussen de andere rij-elementen te wrappen */
    const actions = h("div","am-actions");
    row.appendChild(h("span","am-name", u.displayName + (u.displayName!==u.username ? ` (${u.username})` : "")));
    if(u.role!=="pupil" && can("users.role.change") && u.id!==currentUser.id){
      /* super mag de rol van andere stafaccounts wijzigen - leerlingen blijven altijd leerling */
      const rs = h("select","am-sel");
      ["teacher","admin","super"].forEach(r=>rs.appendChild(new Option(T(roleKey(r)), r)));
      rs.value = u.role;
      rs.addEventListener("change", async ()=>{
        try{ await api("/admin/users/"+u.id, {method:"PATCH", body:{role: rs.value}}); reload(); }
        catch(e){ msg(e.message); }
      });
      row.appendChild(rs);
    }else{
      row.appendChild(h("span","am-role", T(roleKey(u.role))));
    }
    if(u.role==="pupil"){
      /* klas (uitwisselen met andere klassen) */
      const cs = classSel(u.classId);
      cs.addEventListener("change", async ()=>{
        try{ await api("/admin/users/"+u.id, {method:"PATCH", body:{classId: cs.value ? +cs.value : null}}); }
        catch(e){ msg(e.message); }
      });
      row.appendChild(cs);
      /* wachtwoord inzien en aanpassen - alleen zichtbaar zolang de leerling
         nog niet is ingelogd; daarna kan alleen een nieuw wachtwoord gezet worden */
      const pw = h("input","am-pw");
      pw.value = u.password || "";
      pw.placeholder = u.everLoggedIn ? T("amPwHidden") : "";
      pw.title = T("amPw");
      pw.addEventListener("keydown", ev=>ev.stopPropagation());
      pw.addEventListener("change", async ()=>{
        if(pw.value.length < 4) return;
        try{ await api("/admin/users/"+u.id, {method:"PATCH", body:{password: pw.value}}); reload(); }
        catch(e){ msg(e.message); }
      });
      row.appendChild(pw);
      const pwCopy = h("button","am-copy","📋");
      pwCopy.type = "button";
      pwCopy.title = T("amCopy");
      pwCopy.addEventListener("click", e=>{ e.preventDefault(); if(pw.value) copyText(pwCopy, pw.value); });
      actions.appendChild(pwCopy);
      if(u.everLoggedIn){
        const gen = h("button","am-btn","🎲");
        gen.title = T("amGenerate");
        gen.addEventListener("click", async ()=>{
          try{
            const { password } = await api("/admin/genpw?role=pupil");
            await api("/admin/users/"+u.id, {method:"PATCH", body:{password}});
            await reload();
            msg(`${T("amPwSet")} ${password}`, password);
          }catch(e){ msg(e.message); }
        });
        actions.appendChild(gen);
      }
    }else{
      if(u.pending && u.linkCode){
        row.appendChild(h("span","am-code", T("amCode")+": "+u.linkCode));
      }else if(u.pending){
        row.appendChild(h("span","am-code", T("amPending")));
      }
      if(can("users.staffCredentials") && u.role!=="pupil" && u.id!==currentUser.id){
        const nc = h("button","am-btn", T("amNewCode"));
        nc.addEventListener("click", async ()=>{
          try{
            const r = await api("/admin/users/"+u.id, {method:"PATCH", body:{newLinkCode:true}});
            await reload();
            msg(`${T("amCreated")} ${r.linkCode}`, r.linkCode);
          }catch(e){ msg(e.message); }
        });
        actions.appendChild(nc);
        /* direct een nieuw wachtwoord zetten, zonder de koppelcode-activatie */
        const np = h("button","am-btn", T("amNewPw"));
        np.addEventListener("click", async ()=>{
          try{
            const r = await api("/admin/users/"+u.id, {method:"PATCH", body:{generatePassword:true}});
            await reload();
            msg(`${T("amPwSet")} ${r.password}`, r.password);
          }catch(e){ msg(e.message); }
        });
        actions.appendChild(np);
      }
    }
    if(u.id !== currentUser.id){
      const del = h("button","am-del","🗑");
      del.title = T("amDelete") || "";
      del.addEventListener("click", async ()=>{
        if(!confirm(T("amConfirmDel"))) return;
        try{ await api("/admin/users/"+u.id, {method:"DELETE"}); reload(); }
        catch(e){ msg(e.message); }
      });
      actions.appendChild(del);
    }
    if(actions.childNodes.length) row.appendChild(actions);
    return row;
  }

  function addForm(role){
    const f = h("div","am-add");
    const name = h("input","am-inp");
    name.placeholder = T("amUserPh");
    name.addEventListener("keydown", ev=>ev.stopPropagation());
    f.appendChild(name);
    let cs = null;
    if(role==="pupil"){ cs = classSel(""); f.appendChild(cs); }
    let pwInp = null;
    if(role!=="pupil"){
      /* optioneel: meteen zelf een wachtwoord instellen i.p.v. een koppelcode
         (die de gebruiker normaal zelf gebruikt om een wachtwoord te kiezen) */
      pwInp = h("input","am-inp am-pwinp");
      pwInp.type = "password";
      pwInp.autocomplete = "new-password";
      pwInp.placeholder = T("amPwOptional");
      pwInp.addEventListener("keydown", ev=>ev.stopPropagation());
      f.appendChild(pwInp);
      const gen = h("button","am-btn","🎲");
      gen.type = "button";
      gen.title = T("amGenerate");
      gen.addEventListener("click", async ()=>{
        try{
          const { password } = await api("/admin/genpw");
          pwInp.type = "text";
          pwInp.value = password;
        }catch(e){ msg(e.message); }
      });
      f.appendChild(gen);
    }
    const go = h("button","tbtn", T(role==="pupil" ? "amNewPupil" : role==="teacher" ? "amNewTeacher" : role==="admin" ? "amNewAdmin" : "amNewSuper"));
    go.addEventListener("click", async ()=>{
      const body = { role, username: name.value.trim(), displayName: name.value.trim() };
      if(role==="pupil" && cs && cs.value) body.classId = +cs.value;
      if(pwInp && pwInp.value.trim()) body.password = pwInp.value.trim();
      if(currentUser.role==="super" && role!=="super") body.school = +selSchool;
      try{
        const r = await api("/admin/users", { body });
        name.value = "";
        if(pwInp) pwInp.value = "";
        await reload();
        msg(role==="pupil"
          ? `${T("amPupilMade")} ${r.user.password}`
          : r.user.password
            ? `${T("amPwSet")} ${r.user.password}`
            : `${T("amCreated")} ${r.user.linkCode}`,
          r.user.password || r.user.linkCode);
      }catch(e){ msg(e.message); }
    });
    f.appendChild(go);
    return f;
  }

  /* paneel met het resultaat van een multireset (klas/school): een lijst
     nieuwe leerlingwachtwoorden die stuk voor stuk of allemaal ineens
     gekopieerd kunnen worden. Blijft staan tot de beheerder ✕ klikt. */
  function resetPanel(){
    if(!resetResults) return null;
    const box = h("div","am-reset");
    const head = h("div","am-reset-head");
    head.appendChild(h("strong",null, resetResults.title));
    const close = h("button","wclose","✕");
    close.addEventListener("click", ()=>{ resetResults = null; render(); });
    head.appendChild(close);
    box.appendChild(head);
    if(!resetResults.entries.length){
      box.appendChild(h("div","am-msg", T("amResetNone")));
      return box;
    }
    const all = resetResults.entries.map(en=>`${en.displayName}\t${en.password}`).join("\n");
    const copyAll = h("button","am-btn","📋 "+T("amCopyAll"));
    copyAll.type = "button";
    copyAll.addEventListener("click", e=>{ e.preventDefault(); copyText(copyAll, all); });
    box.appendChild(copyAll);
    const list = h("div","am-reset-list");
    resetResults.entries.forEach(en=>{
      const row = h("div","am-reset-row");
      row.appendChild(h("span","am-name", en.displayName));
      row.appendChild(h("span","am-reset-pw", en.password));
      row.appendChild(copyBtn(`${en.displayName}: ${en.password}`));
      list.appendChild(row);
    });
    box.appendChild(list);
    return box;
  }

  /* super: schoolkiezer + nieuwe school */
  function renderScholenPanel(panel){
    const bar = h("div","am-add");
    const sel = h("select","am-sel");
    sel.appendChild(new Option(T("amAllSchools"), ""));
    SCHOOLS.forEach(s=>sel.appendChild(new Option(s.name, s.id)));
    sel.value = selSchool ?? "";
    sel.addEventListener("change", ()=>{ selSchool = sel.value; reload(); });
    bar.appendChild(sel);
    const inp = h("input","am-inp");
    inp.placeholder = T("amNamePh");
    inp.addEventListener("keydown", ev=>ev.stopPropagation());
    bar.appendChild(inp);
    const add = h("button","tbtn", T("amNewSchool"));
    add.addEventListener("click", async ()=>{
      if(!inp.value.trim()) return;
      try{
        const r = await api("/admin/schools", { body:{ name: inp.value.trim() } });
        selSchool = r.school.id; inp.value = "";
        reload();
      }catch(e){ msg(e.message); }
    });
    bar.appendChild(add);
    panel.appendChild(bar);
  }

  /* klassen (admin/super binnen een school) */
  function renderKlassenPanel(panel){
    const schoolChosen = currentUser.role!=="super" || !!selSchool;
    if(!schoolChosen) return;
    const canResetPw = can("schools.resetPasswords");
    const cwrapEl = h("div","am-classes");
    CLASSES.forEach(c=>{
      const chip = h("span","am-chip", c.name);
      if(canResetPw){
        const rs = h("button","am-chipx","🔄");
        rs.title = T("amResetClass");
        rs.addEventListener("click", async ()=>{
          if(!confirm(`${T("amConfirmReset")} ${c.name}?`)) return;
          try{
            const r = await api("/admin/classes/"+c.id+"/reset-passwords", {method:"POST"});
            await reload();
            resetResults = { title: `${T("amResetClass")}: ${c.name}`, entries: r.users };
            render();
          }catch(e){ msg(e.message); }
        });
        chip.appendChild(rs);
        const x = h("button","am-chipx","✕");
        x.addEventListener("click", async ()=>{
          try{ await api("/admin/classes/"+c.id, {method:"DELETE"}); reload(); }
          catch(e){ msg(e.message); }
        });
        chip.appendChild(x);
      }
      cwrapEl.appendChild(chip);
    });
    panel.appendChild(cwrapEl);
    if(canResetPw){
      const f = h("div","am-add");
      const inp = h("input","am-inp");
      inp.placeholder = T("amNamePh");
      inp.addEventListener("keydown", ev=>ev.stopPropagation());
      f.appendChild(inp);
      const go = h("button","tbtn", T("amNewClass"));
      go.addEventListener("click", async ()=>{
        if(!inp.value.trim()) return;
        try{
          await api("/admin/classes", { body:{ name: inp.value.trim(), school: selSchool ? +selSchool : undefined } });
          reload();
        }catch(e){ msg(e.message); }
      });
      f.appendChild(go);
      panel.appendChild(f);

      /* multireset: alle leerlingwachtwoorden van de hele school in één keer */
      const rsAll = h("button","am-btn","🔄 "+T("amResetSchool"));
      rsAll.type = "button";
      rsAll.addEventListener("click", async ()=>{
        const schoolId = currentUser.role==="super" ? selSchool : currentUser.schoolId;
        if(!schoolId) return;
        if(!confirm(T("amConfirmResetSchool"))) return;
        try{
          const r = await api("/admin/schools/"+schoolId+"/reset-passwords", {method:"POST"});
          await reload();
          resetResults = { title: T("amResetSchool"), entries: r.users };
          render();
        }catch(e){ msg(e.message); }
      });
      panel.appendChild(rsAll);
    }
  }

  /* gebruikers: lijst (altijd, ook zonder gekozen school) + aanmaak-formulieren */
  function renderGebruikersPanel(panel){
    const list = h("div","am-list");
    const groups = [["super", T("amSuperGroup")], ["admin", T("roleAdmin")], ["teacher", T("roleTeacher")], ["pupil", T("rolePupil")]];
    groups.forEach(([role, label])=>{
      const us = USERS.filter(u=>u.role===role);
      if(!us.length) return;
      list.appendChild(h("div","am-group", label));
      us.forEach(u=>list.appendChild(userRow(u)));
    });
    panel.appendChild(list);

    /* toevoegen - welke rollen deze gebruiker mag aanmaken (CREATABLE_ROLES) */
    const schoolChosen = currentUser.role!=="super" || !!selSchool;
    const creatable = CREATABLE_ROLES[currentUser.role];
    if(schoolChosen){
      ["pupil","teacher","admin"].forEach(r=>{ if(creatable.includes(r)) panel.appendChild(addForm(r)); });
    }
    if(creatable.includes("super")) panel.appendChild(addForm("super"));
  }

  function switchAdminTab(tab){
    adminTab = tab;
    modal.querySelectorAll(".ed-tabs button").forEach(b=>b.classList.toggle("active", b.dataset.tab===tab));
    modal.querySelectorAll(".am-tabpanel").forEach(p=>{ p.style.display = p.dataset.panel===tab ? "block" : "none"; });
  }

  function render(){
    modal.innerHTML = "";
    modal.appendChild(h("div","am-msg"));
    const rp = resetPanel();
    if(rp) modal.appendChild(rp);

    const tabDefs = [];
    if(currentUser.role==="super") tabDefs.push(["scholen", T("amSchools")]);
    tabDefs.push(["klassen", T("amClasses")]);
    tabDefs.push(["gebruikers", T("amUsers")]);
    if(!tabDefs.some(([t])=>t===adminTab)) adminTab = tabDefs[0][0];

    const tabsBar = h("div","ed-tabs");
    tabDefs.forEach(([t, label])=>{
      const b = h("button", null, label);
      b.type = "button";
      b.dataset.tab = t;
      b.addEventListener("click", ()=>switchAdminTab(t));
      tabsBar.appendChild(b);
    });
    modal.appendChild(tabsBar);

    const panels = { scholen: renderScholenPanel, klassen: renderKlassenPanel, gebruikers: renderGebruikersPanel };
    tabDefs.forEach(([t])=>{
      const panel = h("div","am-tabpanel");
      panel.dataset.panel = t;
      panels[t](panel);
      modal.appendChild(panel);
    });

    switchAdminTab(adminTab);
  }
})();