ccls/src/message_handler.h

// Copyright 2017-2018 ccls Authors
// SPDX-License-Identifier: Apache-2.0

#pragma once

#include "lru_cache.h"
#include "lsp.h"
#include "match.h"
#include "method.h"
#include "query.h"

#include <memory>
#include <optional>
#include <unordered_map>
#include <vector>

struct ClangCompleteManager;
struct CodeCompleteCache;
struct Config;
class DiagnosticsPublisher;
struct VFS;
struct ImportManager;
struct IncludeComplete;
struct MultiQueueWaiter;
struct Project;
struct DB;
struct WorkingFile;
struct WorkingFiles;

// Caches symbols for a single file for semantic highlighting to provide
// relatively stable ids. Only supports xxx files at a time.
struct SemanticHighlightSymbolCache {
  struct Entry {
    SemanticHighlightSymbolCache *all_caches_ = nullptr;

    // The path this cache belongs to.
    std::string path;
    // Detailed symbol name to stable id.
    using TNameToId = std::unordered_map<std::string, int>;
    TNameToId detailed_type_name_to_stable_id;
    TNameToId detailed_func_name_to_stable_id;
    TNameToId detailed_var_name_to_stable_id;

    Entry(SemanticHighlightSymbolCache *all_caches, const std::string &path);

    std::optional<int> TryGetStableId(SymbolKind kind,
                                      const std::string &detailed_name);
    int GetStableId(SymbolKind kind, const std::string &detailed_name);

    TNameToId *GetMapForSymbol_(SymbolKind kind);
  };

  constexpr static int kCacheSize = 10;
  LruCache<std::string, Entry> cache_;
  uint32_t next_stable_id_ = 0;
  std::unique_ptr<GroupMatch> match_;

  SemanticHighlightSymbolCache();
  void Init();
  std::shared_ptr<Entry> GetCacheForFile(const std::string &path);
};

struct Out_CclsPublishSemanticHighlighting
    : public lsOutMessage<Out_CclsPublishSemanticHighlighting> {
  struct Symbol {
    int stableId = 0;
    lsSymbolKind parentKind;
    lsSymbolKind kind;
    uint8_t storage;
    std::vector<std::pair<int, int>> ranges;

    // `lsRanges` is used to compute `ranges`.
    std::vector<lsRange> lsRanges;
  };
  struct Params {
    lsDocumentUri uri;
    std::vector<Symbol> symbols;
  };
  std::string method = "$ccls/publishSemanticHighlighting";
  Params params;
};
MAKE_REFLECT_STRUCT(Out_CclsPublishSemanticHighlighting::Symbol, stableId,
                    parentKind, kind, storage, ranges, lsRanges);
MAKE_REFLECT_STRUCT(Out_CclsPublishSemanticHighlighting::Params, uri, symbols);
MAKE_REFLECT_STRUCT(Out_CclsPublishSemanticHighlighting, jsonrpc, method,
                    params);

// Usage:
//
//  struct FooHandler : MessageHandler {
//    // ...
//  };
//  REGISTER_MESSAGE_HANDLER(FooHandler);
//
// Then there will be a global FooHandler instance in
// |MessageHandler::message_handlers|.

#define REGISTER_MESSAGE_HANDLER(type)                                         \
  static type type##message_handler_instance_;

struct MessageHandler {
  DB *db = nullptr;
  MultiQueueWaiter *waiter = nullptr;
  Project *project = nullptr;
  DiagnosticsPublisher *diag_pub = nullptr;
  VFS *vfs = nullptr;
  ImportManager *import_manager = nullptr;
  SemanticHighlightSymbolCache *semantic_cache = nullptr;
  WorkingFiles *working_files = nullptr;
  ClangCompleteManager *clang_complete = nullptr;
  IncludeComplete *include_complete = nullptr;
  CodeCompleteCache *global_code_complete_cache = nullptr;
  CodeCompleteCache *non_global_code_complete_cache = nullptr;
  CodeCompleteCache *signature_cache = nullptr;

  virtual MethodType GetMethodType() const = 0;
  virtual void Run(std::unique_ptr<InMessage> message) = 0;

  static std::vector<MessageHandler *> *message_handlers;

protected:
  MessageHandler();
};

template <typename TMessage> struct BaseMessageHandler : MessageHandler {
  virtual void Run(TMessage *message) = 0;

  // MessageHandler:
  void Run(std::unique_ptr<InMessage> message) override {
    Run(static_cast<TMessage *>(message.get()));
  }
};

bool FindFileOrFail(DB *db, Project *project, std::optional<lsRequestId> id,
                    const std::string &absolute_path,
                    QueryFile **out_query_file, int *out_file_id = nullptr);

void EmitSkippedRanges(WorkingFile *working_file,
                       const std::vector<Range> &skipped_ranges);

void EmitSemanticHighlighting(DB *db,
                              SemanticHighlightSymbolCache *semantic_cache,
                              WorkingFile *working_file, QueryFile *file);