#include "message_handler.h"
#include "query_utils.h"
#include "pipeline.hh"
using namespace ccls;

namespace {
MethodType kMethodType = "$ccls/vars";

struct In_CclsVars : public RequestInMessage {
  MethodType GetMethodType() const override { return kMethodType; }
  struct Params : lsTextDocumentPositionParams {
    // 1: field
    // 2: local
    // 4: parameter
    unsigned kind = ~0u;
  } params;
};
MAKE_REFLECT_STRUCT(In_CclsVars::Params,
                    textDocument,
                    position,
                    kind);
MAKE_REFLECT_STRUCT(In_CclsVars, id, params);
REGISTER_IN_MESSAGE(In_CclsVars);

struct Handler_CclsVars : BaseMessageHandler<In_CclsVars> {
  MethodType GetMethodType() const override { return kMethodType; }

  void Run(In_CclsVars* request) override {
    auto& params = request->params;
    QueryFile* file;
    if (!FindFileOrFail(db, project, request->id,
                        params.textDocument.uri.GetPath(), &file))
      return;

    WorkingFile* working_file =
        working_files->GetFileByFilename(file->def->path);

    Out_LocationList out;
    out.id = request->id;
    for (SymbolRef sym :
         FindSymbolsAtLocation(working_file, file, params.position)) {
      Usr usr = sym.usr;
      switch (sym.kind) {
        default:
          break;
        case SymbolKind::Var: {
          const QueryVar::Def* def = db->GetVar(sym).AnyDef();
          if (!def || !def->type)
            continue;
          usr = def->type;
          [[fallthrough]];
        }
        case SymbolKind::Type:
          out.result = GetLsLocationExs(
              db, working_files,
              GetVarDeclarations(db, db->Type(usr).instances, params.kind));
          break;
      }
    }
    pipeline::WriteStdout(kMethodType, out);
  }
};
REGISTER_MESSAGE_HANDLER(Handler_CclsVars);
}  // namespace