#include "semantic_highlight_symbol_cache.h"

SemanticHighlightSymbolCache::Entry::Entry(
    SemanticHighlightSymbolCache* all_caches,
    const std::string& path)
    : all_caches_(all_caches), path(path) {}

optional<int> SemanticHighlightSymbolCache::Entry::TryGetStableId(
    SymbolKind kind,
    const std::string& detailed_name) {
  TNameToId* map = GetMapForSymbol_(kind);
  auto it = map->find(detailed_name);
  if (it != map->end())
    return it->second;

  return nullopt;
}

int SemanticHighlightSymbolCache::Entry::GetStableId(
    SymbolKind kind,
    const std::string& detailed_name) {
  optional<int> id = TryGetStableId(kind, detailed_name);
  if (id)
    return *id;

  // Create a new id. First try to find a key in another map.
  all_caches_->cache_.IterateValues([&](const std::shared_ptr<Entry>& entry) {
    optional<int> other_id = entry->TryGetStableId(kind, detailed_name);
    if (other_id) {
      id = other_id;
      return false;
    }
    return true;
  });

  // Create a new id.
  TNameToId* map = GetMapForSymbol_(kind);
  if (!id)
    id = all_caches_->next_stable_id_++;
  return (*map)[detailed_name] = *id;
}

SemanticHighlightSymbolCache::Entry::TNameToId*
SemanticHighlightSymbolCache::Entry::GetMapForSymbol_(SymbolKind kind) {
  switch (kind) {
    case SymbolKind::Type:
      return &detailed_type_name_to_stable_id;
    case SymbolKind::Func:
      return &detailed_func_name_to_stable_id;
    case SymbolKind::Var:
      return &detailed_var_name_to_stable_id;
    case SymbolKind::File:
    case SymbolKind::Invalid:
      break;
  }
  assert(false);
  return nullptr;
}

SemanticHighlightSymbolCache::SemanticHighlightSymbolCache()
    : cache_(kCacheSize) {}

std::shared_ptr<SemanticHighlightSymbolCache::Entry>
SemanticHighlightSymbolCache::GetCacheForFile(const std::string& path) {
  return cache_.Get(
      path, [&, this]() { return std::make_shared<Entry>(this, path); });
}