unit PM.Handler.Audit;

(*
  POST /audit    body {action, site}            -> {ok:true}
  GET  /audit?limit=N&before=<id>               -> [{id, action, ip, created_at}, ...]

  audit_log is auto-purged after 30 days by Database init. The viewer
  reads page-by-page via the `before` cursor (id < before).
*)

interface

implementation

uses
  System.SysUtils, System.JSON,
  IdCustomHTTPServer,
  Data.DB, FireDAC.Comp.Client, FireDAC.Stan.Param,
  PM.Router, PM.JSON, PM.Session, PM.Audit, PM.Database;

function GetClientIP(ARequest: TIdHTTPRequestInfo): string;
begin
  Result := ARequest.RemoteIP;
  if Result = '' then Result := '127.0.0.1';
end;

procedure HandlePostAudit(ARequest: TIdHTTPRequestInfo;
  AResponse: TIdHTTPResponseInfo; const AParams: TArray<string>);
var
  LUserId: Integer;
  LBody: TJSONObject;
  LAction, LSite: string;
begin
  LUserId := Authenticate(ARequest, AResponse);
  RequireCSRF(ARequest, AResponse, LUserId);

  LBody := TJSONHelper.ReadBody(ARequest);
  try
    LAction := LBody.GetValue<string>('action', '');
    LSite   := LBody.GetValue<string>('site',   '');
  finally
    LBody.Free;
  end;

  if LAction = '' then
  begin
    TJSONHelper.SendError(AResponse, 400, 'action required');
    Exit;
  end;

  // Keep the log compact: "autofill:github.com" rather than repeating
  // structured columns we don't have in the current schema.
  if LSite <> '' then
    LAction := LAction + ':' + LSite;

  LogAudit(LUserId, LAction, GetClientIP(ARequest));

  TJSONHelper.SendOK(AResponse);
end;

// GET /audit — return up to `limit` log entries for the current user,
// optionally newer-than-cursor (`before` = id). Most-recent first.
procedure HandleGetAudit(ARequest: TIdHTTPRequestInfo;
  AResponse: TIdHTTPResponseInfo; const AParams: TArray<string>);
var
  LUserId, LLimit, LBefore: Integer;
  LQ: TFDQuery;
  LArr: TJSONArray;
  LObj: TJSONObject;
begin
  LUserId := Authenticate(ARequest, AResponse);

  LLimit  := StrToIntDef(ARequest.Params.Values['limit'], 100);
  if LLimit <= 0 then LLimit := 100;
  if LLimit > 500 then LLimit := 500;
  LBefore := StrToIntDef(ARequest.Params.Values['before'], 0);

  LArr := TJSONArray.Create;
  DB.Lock;
  try
    LQ := TFDQuery.Create(nil);
    try
      LQ.Connection := DB.Connection;
      if LBefore > 0 then
        LQ.SQL.Text :=
          'SELECT id, action, ip, created_at FROM audit_log ' +
          'WHERE user_id = :uid AND id < :b ' +
          'ORDER BY id DESC LIMIT :l'
      else
        LQ.SQL.Text :=
          'SELECT id, action, ip, created_at FROM audit_log ' +
          'WHERE user_id = :uid ' +
          'ORDER BY id DESC LIMIT :l';
      LQ.ParamByName('uid').AsInteger := LUserId;
      LQ.ParamByName('l').AsInteger   := LLimit;
      if LBefore > 0 then
        LQ.ParamByName('b').AsInteger := LBefore;
      LQ.Open;
      while not LQ.Eof do
      begin
        LObj := TJSONObject.Create;
        LObj.AddPair('id', TJSONNumber.Create(LQ.FieldByName('id').AsInteger));
        LObj.AddPair('action', LQ.FieldByName('action').AsString);
        LObj.AddPair('ip', LQ.FieldByName('ip').AsString);
        LObj.AddPair('created_at',
          FormatDateTime('yyyy-mm-dd hh:nn:ss',
            LQ.FieldByName('created_at').AsDateTime));
        LArr.Add(LObj);
        LQ.Next;
      end;
    finally
      LQ.Free;
    end;
  finally
    DB.Unlock;
  end;
  TJSONHelper.SendJSON(AResponse, LArr);
end;

initialization
  Router.Register('POST', '/audit', HandlePostAudit);
  Router.Register('GET',  '/audit', HandleGetAudit);

end.