Add JSON output.

Closes: #3

man/epubgrep.1.adoc

@@ -81,6 +81,8 @@ suppresses errors related to them.
 
 *--debug*::
 Write debug output to the terminal and log file.
+*--json*::
+Output JSON instead of plain text.
 
 == USAGE
 

src/main.cpp

@@ -233,7 +233,14 @@ int main(int argc, char *argv[])
 
     for (const auto &matches : matches_all)
     {
-        output::print_matches(matches, opts, input_files.size() == 1);
+        if (opts.json)
+        {
+            output::json(matches);
+        }
+        else
+        {
+            output::print_matches(matches, opts, input_files.size() == 1);
+        }
     }
 
     LOG(log::sev::info) << "Exiting program with return code " << return_code;

src/options.cpp

@@ -93,6 +93,8 @@ options parse_options(int argc, char *argv[])
          translate("Ignore errors about wrong file formats.") .str().data())
         ("debug",
          translate("Enable debug output.") .str().data())
+        ("json",
+         translate("Output JSON instead of plain text.") .str().data())
     ;
 
     po::options_description options_hidden("Hidden options");
@@ -232,6 +234,7 @@ options parse_again(const po::variables_map &vm)
     opts.dereference_recursive = vm.count("dereference-recursive") > 0;
     opts.ignore_archive_errors = vm.count("ignore-archive-errors") > 0;
     opts.debug = vm.count("debug") > 0;
+    opts.json = vm.count("json") > 0;
 
     if (vm.count("regexp") > 0)
     {

src/options.hpp

@@ -57,6 +57,7 @@ struct options
     std::vector<std::string> input_file;
     bool ignore_archive_errors{false};
     bool debug{false};
+    bool json{false};
 
     //! For the debug output.
     friend std::ostream &operator<<(std::ostream &out, const options &opts);

src/output.cpp

@@ -19,6 +19,7 @@
 #include <boost/locale/message.hpp>
 #include <fmt/format.h>
 #include <fmt/ostream.h> // For compatibility with fmt 4.
+#include <nlohmann/json.hpp>
 #include <termcolor/termcolor.hpp>
 
 #include <iostream>
@@ -39,15 +40,15 @@ void print_matches(const std::vector<search::match> &matches,
     {
         if (!single_file && !opts.no_fn_fs)
         {
-            if (match.epub_filepath != last_epub)
+            if (match.filepath_epub != last_epub)
             {
                 if (!opts.nocolor)
                 {
                     cout << termcolor::yellow;
                 }
                 cout << format(translate("  In {0:s}: \n").str(),
-                               fs::relative(match.epub_filepath));
+                               fs::relative(match.filepath_epub));
-                last_epub = match.epub_filepath;
+                last_epub = match.filepath_epub;
                 if (!opts.nocolor)
                 {
                     cout << termcolor::reset;
@@ -110,4 +111,20 @@ void print_matches(const std::vector<search::match> &matches,
     }
 }
 
+void json(const std::vector<search::match> &matches)
+{
+    nlohmann::json json;
+
+    for (const auto &match : matches)
+    {
+        json[match.filepath_epub].push_back(
+            {{"filepath", match.filepath_inside},
+             {"match", match.text},
+             {"context", match.context},
+             {"headline", match.headline},
+             {"page", match.page}});
+    }
+    std::cout << json.dump(2) << '\n';
+}
+
 } // namespace epubgrep::output

src/output.hpp

@@ -28,6 +28,8 @@ namespace epubgrep::output
 void print_matches(const std::vector<search::match> &matches,
                    const options::options &opts, bool single_file);
 
+void json(const std::vector<search::match> &matches);
+
 } // namespace epubgrep::output
 
 #endif // EPUBGREP_OUTPUT_HPP