Introduce IndexFile class

3 files changed, 80 insertions, 0 deletions

diff --git a/src/index.cc b/src/index.cc
new file mode 100644
index 0000000..c8dc6de
--- /dev/null
+++ b/src/index.cc
@@ -0,0 +1,50 @@
+#include "index.h"
+
+#include "util/query.h"
+#include "util/base64.h"
+
+#include <algorithm>
+
+
+namespace dictzip {
+
+IndexFile::Entry parse_from_line(const std::string& line) {
+	const std::size_t start = line.find_first_of('\t');
+	const std::size_t end   = line.find_last_of('\t');
+
+	return IndexFile::Entry(
+		line.substr(0, start),
+		base64_decode(line.substr(start + 1, end - (start + 1))),
+		base64_decode(line.substr(end + 1)));
+}
+
+IndexFile::Entry::Entry(const std::string& line):
+	IndexFile::Entry{parse_from_line(line)} { }
+
+IndexFile::Entry::Entry(
+	const std::string& word, std::size_t offset, std::size_t length):
+	word(word),
+	offset(offset),
+	length(length) { }
+
+IndexFile::IndexFile(const std::string& path):
+	path_(path) { }
+
+std::vector<IndexFile::Entry> IndexFile::get(const std::string& word) {
+	const std::vector<std::string> lines = get_lines_starting_with(this->path_, word);
+
+	std::vector<Entry> entries;
+	entries.reserve(lines.size());
+
+	std::for_each(
+		lines.begin(),
+		lines.end(),
+		[&entries](const std::string& line) {
+			entries.emplace_back(line);
+		}
+	);
+
+	return entries;
+}
+
+}
diff --git a/src/index.h b/src/index.h
new file mode 100644
index 0000000..50acb2e
--- /dev/null
+++ b/src/index.h
@@ -0,0 +1,29 @@
+#pragma once
+
+#include <string>
+#include <vector>
+#include <cstdint>
+
+namespace dictzip {
+
+class IndexFile {
+public:
+	struct Entry {
+		Entry(const std::string& line);
+		Entry(const std::string& word, std::size_t offset, std::size_t length);
+
+		const std::string word;
+		const std::size_t offset;
+		const std::size_t length;
+	};
+
+	IndexFile(const std::string& path);
+
+	std::vector<Entry> get(const std::string& word);
+
+private:
+	const std::string path_;
+
+};
+
+}
diff --git a/src/util/query.cc b/src/util/query.cc
index f210613..f71b257 100644
--- a/src/util/query.cc
+++ b/src/util/query.cc
@@ -15,6 +15,7 @@ std::vector<std::string> get_lines_starting_with(
 		return std::vector<std::string>{};
 	}
 
+
 	posix_fadvise(fileno(file), 0, 0, 1);  // FDADVICE_SEQUENTIAL
 
 	std::vector<std::string> result;