function doPost(e) {
  try {
    var data = JSON.parse(e.postData.contents);
    var ss = SpreadsheetApp.getActiveSpreadsheet();
    var s1 = ss.getSheetByName("Sessions") || ss.insertSheet("Sessions");
    if (s1.getLastRow() === 0) {
      s1.appendRow(["Date","Heure","Eleve","Identifiant","Chapitre",
        "Titre","Vitesse mots/min","Precision %","Erreurs","Corrects","Duree min"]);
      s1.getRange(1,1,1,11).setFontWeight("bold").setBackground("#3D6B4A").setFontColor("#FFFFFF");
    }
    if (data.sessions) {
      data.sessions.forEach(function(s) {
        s1.appendRow([s.date,s.time||"",s.displayName,s.username,
          s.chapterId,s.chapterTitle||"",s.wpm,s.accuracy||"",
          s.errors,s.correct,s.duration]);
      });
    }
    var s2 = ss.getSheetByName("Progression") || ss.insertSheet("Progression");
    if (s2.getLastRow() === 0) {
      var hdr = ["Eleve","Identifiant","XP","Niveau","Serie"];
      for (var i=1;i<=20;i++) hdr.push("Ch"+i+"%");
      s2.appendRow(hdr);
      s2.getRange(1,1,1,hdr.length).setFontWeight("bold").setBackground("#3D2010").setFontColor("#FFFFFF");
    }
    if (data.students) {
      if (s2.getLastRow()>1) s2.deleteRows(2,s2.getLastRow()-1);
      data.students.forEach(function(s) {
        var row=[s.displayName,s.username,s.xp||0,s.level||"",s.streak||0];
        for(var i=1;i<=20;i++) row.push(s["ch"+i+"_pct"]||0);
        s2.appendRow(row);
      });
    }
    return ContentService.createTextOutput(JSON.stringify({status:"ok"})).setMimeType(ContentService.MimeType.JSON);
  } catch(err) {
    return ContentService.createTextOutput(JSON.stringify({status:"error",msg:err.toString()})).setMimeType(ContentService.MimeType.JSON);
  }
}
function doGet(){return ContentService.createTextOutput("ClavHero sync OK");}