#pragma once

#include "language_server_api.h"
#include "utils.h"

#include <clang-c/Index.h>
#include <optional.h>

#include <mutex>
#include <string>

struct WorkingFile {
  int version = 0;
  std::string filename;

  std::string buffer_content;
  // Note: This assumes 0-based lines (1-based lines are normally assumed).
  std::vector<std::string> index_lines;
  // Note: This assumes 0-based lines (1-based lines are normally assumed).
  // Note: all_buffer_lines is whitespace stripped.
  std::vector<std::string> all_buffer_lines;
  // Note: This assumes 0-based lines (1-based lines are normally assumed).
  std::vector<std::string> raw_buffer_lines;
  // This map goes from disk-line -> indicies+1 in index_lines.
  // Note: The items in the value entry are 1-based lines.
  std::unordered_map<std::string, std::vector<int>> index_lines_lookup;
  // This map goes from buffer-line -> indices+1 in all_buffer_lines.
  // Note: The items in the value entry are 1-based liness.
  std::unordered_map<std::string, std::vector<int>> all_buffer_lines_lookup;
  // A set of diagnostics that have been reported for this file.
  // NOTE: _ is appended because it must be accessed under the WorkingFiles
  // lock!
  std::vector<lsDiagnostic> diagnostics_;

  WorkingFile(const std::string& filename, const std::string& buffer_content);

  // This should be called when the indexed content has changed.
  void SetIndexContent(const std::string& index_content);
  // This should be called whenever |buffer_content| has changed.
  void OnBufferContentUpdated();

  // Find the buffer-line which should be shown for |indexed_line|. This
  // accepts and returns 1-based lines.
  optional<int> GetBufferLineFromIndexLine(int indexed_line) const;
  // Find the indexed-line which should be shown for |buffer_line|. This
  // accepts and returns 1-based lines.
  optional<int> GetIndexLineFromBufferLine(int buffer_line) const;

  optional<std::string> GetBufferLineContentFromIndexLine(
      int indexed_line,
      optional<int>* out_buffer_line) const;

  // TODO: Move FindClosestCallNameInBuffer and FindStableCompletionSource into
  // lex_utils.h/cc

  // Finds the closest 'callable' name prior to position. This is used for
  // signature help to filter code completion results.
  //
  // |completion_position| will be point to a good code completion location to
  // for fetching signatures.
  std::string FindClosestCallNameInBuffer(
      lsPosition position,
      int* active_parameter,
      lsPosition* completion_position = nullptr) const;

  // Returns a relatively stable completion position (it jumps back until there
  // is a non-alphanumeric character).
  //
  // The out param |is_global_completion| is set to true if this looks like a
  // global completion.
  // The out param |existing_completion| is set to any existing completion
  // content the user has entered.
  lsPosition FindStableCompletionSource(lsPosition position,
                                        bool* is_global_completion,
                                        std::string* existing_completion) const;
};

struct WorkingFiles {
  struct Snapshot {
    struct File {
      std::string filename;
      std::string content;
    };

    std::vector<CXUnsavedFile> AsUnsavedFiles() const;
    std::vector<File> files;
  };


  //
  // :: IMPORTANT :: All methods in this class are guarded by a single lock.
  //

  // Find the file with the given filename.
  WorkingFile* GetFileByFilename(const std::string& filename);
  WorkingFile* GetFileByFilenameNoLock(const std::string& filename);

  // Run |action| under the lock.
  void DoAction(const std::function<void()>& action);
  // Run |action| on the file identified by |filename|. This executes under the
  // lock.
  void DoActionOnFile(const std::string& filename,
                      const std::function<void(WorkingFile* file)>& action);

  WorkingFile* OnOpen(const lsTextDocumentItem& open);
  void OnChange(const lsTextDocumentDidChangeParams& change);
  void OnClose(const lsTextDocumentItem& close);

  // If |filter_paths| is non-empty, only files which contain any of the given
  // strings. For example, {"foo", "bar"} means that every result has either the
  // string "foo" or "bar" contained within it.
  Snapshot AsSnapshot(const std::vector<std::string>& filter_paths);

  // Use unique_ptrs so we can handout WorkingFile ptrs and not have them
  // invalidated if we resize files.
  std::vector<std::unique_ptr<WorkingFile>> files;
  std::mutex files_mutex;  // Protects |files|.
};