diff --git a/task1_git/.gitignore b/task1_git/.gitignore
new file mode 100644
index 0000000..feb4217
--- /dev/null
+++ b/task1_git/.gitignore
@@ -0,0 +1,32 @@
+# Compiled class file
+*.class
+
+# Log file
+*.log
+
+# BlueJ files
+*.ctxt
+
+# Mobile Tools for Java (J2ME)
+.mtj.tmp/
+
+# Package Files #
+*.jar
+*.war
+*.nar
+*.ear
+*.zip
+*.tar.gz
+*.rar
+
+# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
+hs_err_pid*
+
+build
+.gradle
+.idea
+*.iml
+out/
+
+.m_git
+kek/
\ No newline at end of file
diff --git a/task1_git/Readme.md b/task1_git/Readme.md
new file mode 100644
index 0000000..8855357
--- /dev/null
+++ b/task1_git/Readme.md
@@ -0,0 +1,44 @@
+# Git
+
+### Description
+
+This repository contains simple draft of **git**.
+
+### Usage
+
+The following commands are available:
+```
+init
+add
+commit
+reset
+log [from_commit]
+checkout
+```
+where *<smth>* means mandatory argument while *[smth]*
+implies he optional one.
+*commit* is represented as short (at least 7 symbols) or entire hash code.
+
+
+### File hierarchy
+
+ .m_git/
+ logs/
+ [log_file_for_branch]
+ storage/
+ [dir_as_hashcode]
+ [file]
+ index/
+ [file]
+ HEAD - file with information about current state
+
+
+### How to build and run
+
+In order to run this app, follow this steps:
+
+* clone this repository
+* checkout on branch *task1_git*
+* run `./gradlew installDist`
+* go to the `./build/install/task1_git/bin/`
+* execute `task1_git` (or `task1_git.bat` on Windows)
\ No newline at end of file
diff --git a/task1_git/build.gradle b/task1_git/build.gradle
new file mode 100644
index 0000000..c22f615
--- /dev/null
+++ b/task1_git/build.gradle
@@ -0,0 +1,21 @@
+group 'ru.ifmo'
+version '1.0-SNAPSHOT'
+
+apply plugin: 'java'
+apply plugin: 'application'
+
+mainClassName = "ru.ifmo.git.Git"
+
+sourceCompatibility = 1.8
+
+repositories {
+ mavenCentral()
+}
+
+dependencies {
+ testCompile group: 'junit', name: 'junit', version: '4.12'
+ compile group: 'net.sourceforge.argparse4j', name: 'argparse4j', version: '0.2.0'
+ compile group: 'org.apache.commons', name: 'commons-io', version: '1.3.2'
+ implementation 'com.google.code.gson:gson:2.8.5'
+}
+
diff --git a/task1_git/gradle/wrapper/gradle-wrapper.properties b/task1_git/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 0000000..dd32b3d
--- /dev/null
+++ b/task1_git/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,6 @@
+#Fri Sep 14 13:38:27 MSK 2018
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.0-all.zip
diff --git a/task1_git/gradlew b/task1_git/gradlew
new file mode 100755
index 0000000..cccdd3d
--- /dev/null
+++ b/task1_git/gradlew
@@ -0,0 +1,172 @@
+#!/usr/bin/env sh
+
+##############################################################################
+##
+## Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+ ls=`ls -ld "$PRG"`
+ link=`expr "$ls" : '.*-> \(.*\)$'`
+ if expr "$link" : '/.*' > /dev/null; then
+ PRG="$link"
+ else
+ PRG=`dirname "$PRG"`"/$link"
+ fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS=""
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+ echo "$*"
+}
+
+die () {
+ echo
+ echo "$*"
+ echo
+ exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+ CYGWIN* )
+ cygwin=true
+ ;;
+ Darwin* )
+ darwin=true
+ ;;
+ MINGW* )
+ msys=true
+ ;;
+ NONSTOP* )
+ nonstop=true
+ ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+ if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+ # IBM's JDK on AIX uses strange locations for the executables
+ JAVACMD="$JAVA_HOME/jre/sh/java"
+ else
+ JAVACMD="$JAVA_HOME/bin/java"
+ fi
+ if [ ! -x "$JAVACMD" ] ; then
+ die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+ fi
+else
+ JAVACMD="java"
+ which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+ MAX_FD_LIMIT=`ulimit -H -n`
+ if [ $? -eq 0 ] ; then
+ if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+ MAX_FD="$MAX_FD_LIMIT"
+ fi
+ ulimit -n $MAX_FD
+ if [ $? -ne 0 ] ; then
+ warn "Could not set maximum file descriptor limit: $MAX_FD"
+ fi
+ else
+ warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+ fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+ GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin ; then
+ APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+ CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+ JAVACMD=`cygpath --unix "$JAVACMD"`
+
+ # We build the pattern for arguments to be converted via cygpath
+ ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+ SEP=""
+ for dir in $ROOTDIRSRAW ; do
+ ROOTDIRS="$ROOTDIRS$SEP$dir"
+ SEP="|"
+ done
+ OURCYGPATTERN="(^($ROOTDIRS))"
+ # Add a user-defined pattern to the cygpath arguments
+ if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+ OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+ fi
+ # Now convert the arguments - kludge to limit ourselves to /bin/sh
+ i=0
+ for arg in "$@" ; do
+ CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+ CHECK2=`echo "$arg"|egrep -c "^-"` ### Determine if an option
+
+ if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then ### Added a condition
+ eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+ else
+ eval `echo args$i`="\"$arg\""
+ fi
+ i=$((i+1))
+ done
+ case $i in
+ (0) set -- ;;
+ (1) set -- "$args0" ;;
+ (2) set -- "$args0" "$args1" ;;
+ (3) set -- "$args0" "$args1" "$args2" ;;
+ (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+ (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+ (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+ (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+ (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+ (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+ esac
+fi
+
+# Escape application args
+save () {
+ for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+ echo " "
+}
+APP_ARGS=$(save "$@")
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
+if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then
+ cd "$(dirname "$0")"
+fi
+
+exec "$JAVACMD" "$@"
diff --git a/task1_git/gradlew.bat b/task1_git/gradlew.bat
new file mode 100644
index 0000000..e95643d
--- /dev/null
+++ b/task1_git/gradlew.bat
@@ -0,0 +1,84 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS=
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/task1_git/settings.gradle b/task1_git/settings.gradle
new file mode 100644
index 0000000..dd874e4
--- /dev/null
+++ b/task1_git/settings.gradle
@@ -0,0 +1,2 @@
+rootProject.name = 'task1_git'
+
diff --git a/task1_git/src/main/java/ru/ifmo/git/Git.java b/task1_git/src/main/java/ru/ifmo/git/Git.java
new file mode 100644
index 0000000..626a22f
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/Git.java
@@ -0,0 +1,27 @@
+package ru.ifmo.git;
+
+import ru.ifmo.git.masters.GitParser;
+import ru.ifmo.git.util.*;
+
+import net.sourceforge.argparse4j.inf.*;
+
+public class Git {
+
+ public static void main(String[] args) {
+ GitParser gitParser = new GitParser();
+ try {
+ Namespace ns = gitParser.parseArgs(args);
+ Command command = (Command) ns.getAttrs().remove("cmd");
+ CommandResult result = command.execute(ns.getAttrs());
+ if(result.getStatus() != ExitStatus.SUCCESS) {
+ System.out.println("exit with code " + result.getStatus());
+ }
+ System.out.print(result.getMessage().read());
+ } catch (ArgumentParserException e) {
+ gitParser.handleError(e);
+ } catch (GitException e) {
+ System.out.print(e.getMessage());
+ }
+ }
+
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/commands/Add.java b/task1_git/src/main/java/ru/ifmo/git/commands/Add.java
new file mode 100644
index 0000000..cc6fc74
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/commands/Add.java
@@ -0,0 +1,42 @@
+package ru.ifmo.git.commands;
+
+import ru.ifmo.git.masters.*;
+import ru.ifmo.git.util.*;
+
+import java.io.*;
+import java.nio.file.Paths;
+import java.util.*;
+
+public class Add implements Command {
+
+ private List files = new LinkedList<>();
+
+ @Override
+ public boolean correctArgs(Map args) {
+ if (args.isEmpty()) {
+ return false;
+ }
+ //noinspection unchecked
+ List fileNames = ((List) args.get(""));
+ for (String fileName : fileNames) {
+ File file = Paths.get(GitTree.cwd(), fileName).toFile();
+ if (!file.exists()) {
+ return false;
+ }
+ files.add(file);
+ }
+ return true;
+ }
+
+ @Override
+ public CommandResult execute(Map args) {
+ try {
+ checkRepoAndArgs(args);
+ StorageMaster.copyAll(files, new File(GitTree.index()));
+ return new CommandResult(ExitStatus.SUCCESS, "add: done!\n");
+ } catch (GitException e) {
+ return new CommandResult(ExitStatus.ERROR, "add: " + e.getMessage());
+ }
+ }
+
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/commands/Checkout.java b/task1_git/src/main/java/ru/ifmo/git/commands/Checkout.java
new file mode 100644
index 0000000..e3588ca
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/commands/Checkout.java
@@ -0,0 +1,34 @@
+package ru.ifmo.git.commands;
+
+import ru.ifmo.git.masters.*;
+import ru.ifmo.git.util.*;
+
+import java.io.*;
+import java.util.Map;
+
+import org.apache.commons.io.FileUtils;
+
+public class Checkout implements Command {
+
+ private String commit;
+
+ @Override
+ public boolean correctArgs(Map args) {
+ commit = (String) args.get("");
+ return commit.length() > 6;
+ }
+
+ @Override
+ public CommandResult execute(Map args) {
+ try {
+ checkRepoAndArgs(args);
+ File commitDir = FileMaster.findCommitInStorage(commit);
+ FileUtils.copyDirectory(commitDir, new File(GitTree.cwd()));
+ FileMaster.changeCurHash(commitDir.getName(), false);
+ } catch (IOException | GitException e) {
+ return new CommandResult(ExitStatus.ERROR, e.getMessage());
+ }
+ return new CommandResult(ExitStatus.SUCCESS, "checkout: done!");
+ }
+
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/commands/Commit.java b/task1_git/src/main/java/ru/ifmo/git/commands/Commit.java
new file mode 100644
index 0000000..d3a8d1f
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/commands/Commit.java
@@ -0,0 +1,86 @@
+package ru.ifmo.git.commands;
+
+import ru.ifmo.git.masters.*;
+import ru.ifmo.git.util.*;
+import com.google.gson.Gson;
+
+import java.io.*;
+import java.nio.file.Paths;
+import java.text.*;
+import java.util.*;
+
+public class Commit implements Command {
+
+ private HeadInfo headInfo;
+ private CommitInfo commitInfo = new CommitInfo();
+ private List files = new LinkedList<>();
+ private String message;
+
+ @Override
+ public boolean correctArgs(Map args) {
+ //noinspection unchecked
+ List fileNames = ((List) args.get(""));
+ for (String fileName : fileNames) {
+ File file = Paths.get(GitTree.index(), fileName).toFile();
+ if (!file.exists()) {
+ return false;
+ }
+ files.add(file);
+ }
+ message = (String) args.get("message");
+ return true;
+ }
+
+ @Override
+ public CommandResult execute(Map args) {
+ try {
+ if(!correctArgs(args)) {
+ return new CommandResult(ExitStatus.ERROR, "try git add first\n");
+ }
+ checkRepoAndArgs(args);
+ headInfo = FileMaster.getHeadInfo(new File(GitTree.head()));
+ setCommitInfo();
+ StorageMaster.copyAll(files, Paths.get(GitTree.storage(), headInfo.currentHash).toFile());
+ writeLog();
+ return new CommandResult(ExitStatus.SUCCESS, "commit: done!\n");
+ } catch (GitException e) {
+ return new CommandResult(ExitStatus.ERROR, "commit: " + e.getMessage());
+ }
+ }
+
+
+ private void setCommitInfo() throws GitException {
+ commitInfo.author = System.getProperty("user.name");
+ commitInfo.message = message;
+ commitInfo.branch = headInfo.branchName;
+
+ DateFormat df = new SimpleDateFormat("EEE MMM dd HH:mm:ss yyyy ZZ");
+ Calendar calendar = Calendar.getInstance();
+ commitInfo.time = df.format(calendar.getTime());
+
+ String hash = String.valueOf(commitInfo.time.concat(String.valueOf(GitTree.cwd())).hashCode());
+ commitInfo.hash = (UUID.randomUUID().toString() + hash).replaceAll("-", "");
+
+ boolean moveHead = headInfo.headHash.equals(headInfo.currentHash);
+ FileMaster.changeCurHash(commitInfo.hash, moveHead);
+ }
+
+ private void writeLog() throws GitException {
+ if (commitInfo.message.isEmpty()) {
+ getUserMessage();
+ }
+ String logContent = (new Gson()).toJson(commitInfo);
+ String logFile = Paths.get(GitTree.log(), headInfo.branchName).toString();
+ FileMaster.writeToFile(logFile, logContent, true);
+ }
+
+ private void getUserMessage() {
+ try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in))) {
+ System.out.print("please enter message: ");
+ commitInfo.message = br.readLine();
+ } catch (IOException e) {
+ commitInfo.message = "no message";
+ }
+ }
+
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/commands/Init.java b/task1_git/src/main/java/ru/ifmo/git/commands/Init.java
new file mode 100644
index 0000000..66d0533
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/commands/Init.java
@@ -0,0 +1,66 @@
+package ru.ifmo.git.commands;
+
+import ru.ifmo.git.masters.*;
+import ru.ifmo.git.util.*;
+
+import java.io.*;
+import java.nio.file.Paths;
+import java.util.*;
+
+import com.google.gson.Gson;
+
+public class Init implements Command {
+
+ private File gitDirectory = null;
+
+ @Override
+ public boolean correctArgs(Map args) {
+ return args == null || args.size() == 0;
+ }
+
+ @Override
+ public CommandResult execute(Map args) {
+ if (!correctArgs(args)) {
+ return new CommandResult(ExitStatus.ERROR, "init: wrong arguments\n");
+ }
+ gitDirectory = Paths.get(GitTree.repo()).toFile();
+ CommandResult result = new CommandResult(ExitStatus.SUCCESS);
+ Message message = new Message();
+ if (repositoryExists()) {
+ message.write("reinitialized existing ");
+ } else {
+ if (initRepository()) {
+ message.write("initialized empty ");
+ } else {
+ result.setStatus(ExitStatus.ERROR);
+ message.write("fail to init ");
+ }
+ }
+ message.write("Git repository in " + gitDirectory.getAbsolutePath() + "\n");
+ result.setMessage(message);
+ return result;
+ }
+
+ private boolean initRepository() {
+ return gitDirectory.mkdir() && createDirs() && createFiles();
+ }
+
+ private boolean createDir(String dirName) {
+ File newDir = Paths.get(GitTree.repo(), dirName).toFile();
+ return newDir.exists() || newDir.mkdirs();
+ }
+
+ private boolean createDirs() {
+ return
+ createDir("/logs/") &&
+ createDir("/storage/") &&
+ createDir("/index/");
+ }
+
+ private boolean createFiles() {
+ HeadInfo masterInfo = new HeadInfo("master");
+ String headInfo = (new Gson()).toJson(masterInfo);
+ return StorageMaster.createFileWithContent(GitTree.head(), headInfo);
+ }
+
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/commands/Log.java b/task1_git/src/main/java/ru/ifmo/git/commands/Log.java
new file mode 100644
index 0000000..8cdefdb
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/commands/Log.java
@@ -0,0 +1,70 @@
+package ru.ifmo.git.commands;
+
+import ru.ifmo.git.masters.*;
+import ru.ifmo.git.util.*;
+
+import java.io.*;
+import java.nio.file.Paths;
+import java.util.*;
+import java.util.function.Predicate;
+
+public class Log implements Command {
+
+ private HeadInfo headInfo;
+ private String commit;
+
+ @Override
+ public boolean correctArgs(Map args) {
+ if (args.size() == 1) {
+ commit = (String) args.get("");
+ return true;
+ }
+ return (args.size() == 0);
+ }
+
+ @Override
+ public CommandResult execute(Map args) {
+ try {
+ checkRepoAndArgs(args);
+ headInfo = FileMaster.getHeadInfo(new File(GitTree.head()));
+ } catch (GitException e) {
+ return new CommandResult(ExitStatus.ERROR, "error while reading HEAD\n");
+ }
+ return readLog(Paths.get(GitTree.log(), headInfo.branchName).toFile(), commit);
+ }
+
+ private CommandResult readLog(File logFile, String revision) {
+ if (logFile.exists()) {
+ Message logContent = new Message();
+ List history;
+ try {
+ history = FileMaster.getHistory(logFile);
+ } catch (GitException e) {
+ return new CommandResult(ExitStatus.ERROR, e.getMessage());
+ }
+ if (history.size() == 0) {
+ return emptyLogResult();
+ }
+ history.stream().filter(
+ new Predicate() {
+
+ private boolean include = (revision == null || revision.isEmpty());
+
+ @Override
+ public boolean test(CommitInfo commitInfo) {
+ include = include || commitInfo.hash.startsWith(revision);
+ return include;
+ }
+ }
+ ).forEach(info -> logContent.write(info.toString()));
+ return new CommandResult(ExitStatus.SUCCESS, logContent);
+ }
+ return emptyLogResult();
+ }
+
+ private CommandResult emptyLogResult() {
+ String failMessage = "fatal: your current branch '" + headInfo.branchName + "' does not have any commits yet\n";
+ return new CommandResult(ExitStatus.FAILURE, failMessage);
+ }
+
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/commands/Reset.java b/task1_git/src/main/java/ru/ifmo/git/commands/Reset.java
new file mode 100644
index 0000000..6c8a311
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/commands/Reset.java
@@ -0,0 +1,34 @@
+package ru.ifmo.git.commands;
+
+import ru.ifmo.git.masters.*;
+import ru.ifmo.git.util.*;
+
+import java.io.*;
+import java.util.Map;
+
+import org.apache.commons.io.FileUtils;
+
+public class Reset implements Command {
+
+ private String commit;
+
+ @Override
+ public boolean correctArgs(Map args) {
+ commit = (String) args.get("");
+ return commit.length() > 6;
+ }
+
+ @Override
+ public CommandResult execute(Map args) {
+ try {
+ checkRepoAndArgs(args);
+ File commitDir = FileMaster.findCommitInStorage(commit);
+ FileUtils.copyDirectory(commitDir, new File(GitTree.index()));
+ FileMaster.changeCurHash(commitDir.getName(), true);
+ } catch (IOException | GitException e) {
+ return new CommandResult(ExitStatus.ERROR, e.getMessage());
+ }
+ return new CommandResult(ExitStatus.SUCCESS, "reset: done!");
+ }
+
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/masters/FileMaster.java b/task1_git/src/main/java/ru/ifmo/git/masters/FileMaster.java
new file mode 100644
index 0000000..c2907e9
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/masters/FileMaster.java
@@ -0,0 +1,67 @@
+package ru.ifmo.git.masters;
+
+import com.google.gson.*;
+import org.apache.commons.io.*;
+
+import ru.ifmo.git.util.*;
+
+import java.io.*;
+import java.util.*;
+
+public class FileMaster {
+
+ static public List getHistory(File logFile) throws GitException {
+ List history = new ArrayList<>();
+ try (BufferedReader br = new BufferedReader(new FileReader(logFile))) {
+ for (String line; (line = br.readLine()) != null; ) {
+ history.add(new GsonBuilder().create().fromJson(line, CommitInfo.class));
+ }
+ } catch (IOException e) {
+ throw new GitException("error while reading log\n");
+ }
+ return history;
+ }
+
+ public static HeadInfo getHeadInfo(File headFile) throws GitException {
+ String headJson;
+ try (FileInputStream inputStream = new FileInputStream(headFile.getAbsolutePath())) {
+ headJson = IOUtils.toString(inputStream);
+ } catch (IOException e) {
+ throw new GitException("error while reading HEAD\n");
+ }
+ return new GsonBuilder().create().fromJson(headJson, HeadInfo.class);
+ }
+
+ static public void writeToFile(String fileName, String content, boolean append) throws GitException {
+ File file = new File(fileName);
+ try (BufferedWriter writer = new BufferedWriter(new FileWriter(file, append))) {
+ writer.write(content + (append ? "\n" : ""));
+ } catch (IOException e) {
+ throw new GitException("error while writing to " + file.getName());
+ }
+ }
+
+ static public void changeCurHash(String newHash, boolean withHead) throws GitException {
+ HeadInfo headInfo = FileMaster.getHeadInfo(new File(GitTree.head()));
+ headInfo.setCurrentHash(newHash);
+ if (withHead) {
+ headInfo.setHeadHash(newHash);
+ }
+ String newHeadContent = (new Gson()).toJson(headInfo);
+ FileMaster.writeToFile(GitTree.head(), newHeadContent, false);
+ }
+
+ static public File findCommitInStorage(String desiredCommit) throws GitException {
+ File[] allCommits = new File(GitTree.storage()).listFiles();
+ if (allCommits == null || allCommits.length == 0) {
+ throw new GitException("no commits yet\n");
+ }
+ Optional commitDir = Arrays.stream(allCommits)
+ .filter(file -> file.getName().startsWith(desiredCommit)).findFirst();
+ if (!commitDir.isPresent()) {
+ throw new GitException("no such commit\n");
+ }
+ return commitDir.get();
+ }
+
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/masters/GitParser.java b/task1_git/src/main/java/ru/ifmo/git/masters/GitParser.java
new file mode 100644
index 0000000..48e3d8a
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/masters/GitParser.java
@@ -0,0 +1,65 @@
+package ru.ifmo.git.masters;
+
+import net.sourceforge.argparse4j.*;
+import net.sourceforge.argparse4j.inf.*;
+import ru.ifmo.git.commands.*;
+
+public class GitParser {
+
+ private ArgumentParser gitParser;
+
+ public GitParser() {
+ createGitParser();
+ }
+
+ private void createGitParser() {
+ gitParser = ArgumentParsers.newArgumentParser("git");
+ gitParser.defaultHelp(true)
+ .description("A version control system created by lergor.");
+
+ Subparsers subparsers = gitParser.addSubparsers()
+ .title("These are common Git commands used in various situations:");
+
+ Subparser parserInit = subparsers.addParser("init")
+ .setDefault("cmd", new Init())
+ .help("Create an empty Git repository or reinitialize an existing one");
+
+ Subparser parserAdd = subparsers.addParser("add")
+ .setDefault("cmd", new Add())
+ .help("Add file contents to the index");
+ parserAdd.addArgument("").type(String.class)
+ .required(true).nargs("+");
+
+ Subparser parserCommit = subparsers.addParser("commit")
+ .setDefault("cmd", new Commit())
+ .help("Record changes to the repository");
+ parserCommit.addArgument("message").type(String.class);
+ parserCommit.addArgument("").type(String.class).nargs("+");
+
+ Subparser parserReset = subparsers.addParser("reset")
+ .setDefault("cmd", new Reset())
+ .help("Reset current HEAD to the specified state");
+ parserReset.addArgument("").type(String.class)
+ .required(true);
+
+ Subparser parserLog = subparsers.addParser("log")
+ .setDefault("cmd", new Log())
+ .help("Show commit logs");
+ parserLog.addArgument("").type(String.class).nargs("?");
+
+ Subparser parserCheckout = subparsers.addParser("checkout")
+ .setDefault("cmd", new Checkout())
+ .help("Switch branches or restore working tree files");
+ parserCheckout.addArgument("").type(String.class);
+
+ }
+
+ public Namespace parseArgs(String[] args) throws ArgumentParserException {
+ return gitParser.parseArgs(args);
+ }
+
+ public void handleError(ArgumentParserException e) {
+ gitParser.handleError(e);
+ }
+
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/masters/StorageMaster.java b/task1_git/src/main/java/ru/ifmo/git/masters/StorageMaster.java
new file mode 100644
index 0000000..33608b2
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/masters/StorageMaster.java
@@ -0,0 +1,52 @@
+package ru.ifmo.git.masters;
+
+import org.apache.commons.io.FileUtils;
+import ru.ifmo.git.util.*;
+
+import java.io.*;
+import java.util.*;
+
+public class StorageMaster {
+
+ static public void copyAll(List args, File targetDir) throws GitException {
+ if (targetDir.exists() || (!targetDir.exists() && targetDir.mkdirs())) {
+ for (File file : args) {
+ try {
+ if (file.isFile()) {
+ FileUtils.copyFileToDirectory(file, targetDir);
+ } else if (file.isDirectory()) {
+ FileUtils.copyDirectoryToDirectory(file, targetDir);
+ }
+ } catch (IOException e) {
+ throw new GitException(e.getMessage());
+ }
+ }
+ }
+ }
+
+ static public boolean createFileWithContent(String fileName, String content) {
+ if (checkAndCreateFile(fileName)) {
+ try {
+ FileUtils.writeStringToFile(new File(fileName), content, "UTF-8");
+ } catch (IOException e) {
+ return false;
+ }
+ }
+ return true;
+ }
+
+ private static boolean checkAndCreateFile(String fileName) {
+ File file = new File(fileName);
+ if (!file.exists()) {
+ try {
+ if (file.createNewFile()) {
+ return file.setReadable(true) && file.setWritable(true);
+ }
+ } catch (IOException e) {
+ return false;
+ }
+ }
+ return file.canRead() && file.canWrite();
+ }
+
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/util/Command.java b/task1_git/src/main/java/ru/ifmo/git/util/Command.java
new file mode 100644
index 0000000..10bad2b
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/util/Command.java
@@ -0,0 +1,25 @@
+package ru.ifmo.git.util;
+
+import java.io.File;
+import java.util.*;
+
+public interface Command {
+
+ default boolean repositoryExists() {
+ return new File(GitTree.repo()).exists();
+ }
+
+ boolean correctArgs(Map args);
+
+ default void checkRepoAndArgs(Map args) throws GitException {
+ if (!repositoryExists()) {
+ throw new GitException("fatal: Not a git repository: .m_git\n");
+ }
+ if (!correctArgs(args)) {
+ throw new GitException("wrong arguments\n");
+ }
+ }
+
+ CommandResult execute(Map args) throws GitException;
+
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/util/CommandResult.java b/task1_git/src/main/java/ru/ifmo/git/util/CommandResult.java
new file mode 100644
index 0000000..dc33213
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/util/CommandResult.java
@@ -0,0 +1,43 @@
+package ru.ifmo.git.util;
+
+public class CommandResult {
+
+ private ExitStatus status;
+ private Message message;
+
+ public CommandResult(ExitStatus status) {
+ this.status = status;
+ this.message = new Message();
+ }
+
+ public CommandResult(ExitStatus status, Message message) {
+ this.status = status;
+ this.message = message;
+ }
+
+ public CommandResult(ExitStatus status, String message) {
+ this.status = status;
+ this.message = new Message(message);
+ }
+
+ public ExitStatus getStatus() {
+ return status;
+ }
+
+ public void setStatus(ExitStatus status) {
+ this.status = status;
+ }
+
+ public Message getMessage() {
+ return message;
+ }
+
+ public void setMessage(Message message) {
+ this.message = message;
+ }
+
+ public void setMessage(String message) {
+ this.message = new Message(message);
+ }
+
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/util/CommitInfo.java b/task1_git/src/main/java/ru/ifmo/git/util/CommitInfo.java
new file mode 100644
index 0000000..aa0908a
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/util/CommitInfo.java
@@ -0,0 +1,20 @@
+package ru.ifmo.git.util;
+
+public class CommitInfo {
+ public String author;
+ public String time;
+ public String hash;
+ public String message;
+ public String branch;
+
+ public CommitInfo() {
+ }
+
+ public String toString() {
+ return "commit " + hash + "\n" +
+ "Author:\t" + author + "\n" +
+ "Date:\t" + time + "\n" +
+ "\t\t" + message + "\n\n";
+ }
+
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/util/ExitStatus.java b/task1_git/src/main/java/ru/ifmo/git/util/ExitStatus.java
new file mode 100644
index 0000000..365b529
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/util/ExitStatus.java
@@ -0,0 +1,5 @@
+package ru.ifmo.git.util;
+
+public enum ExitStatus {
+ SUCCESS, FAILURE, ERROR
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/util/GitException.java b/task1_git/src/main/java/ru/ifmo/git/util/GitException.java
new file mode 100644
index 0000000..10cfb2e
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/util/GitException.java
@@ -0,0 +1,9 @@
+package ru.ifmo.git.util;
+
+public class GitException extends Exception {
+
+ public GitException(String message) {
+ super(message);
+ }
+
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/util/GitTree.java b/task1_git/src/main/java/ru/ifmo/git/util/GitTree.java
new file mode 100644
index 0000000..9fd31e0
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/util/GitTree.java
@@ -0,0 +1,31 @@
+package ru.ifmo.git.util;
+
+import java.nio.file.Paths;
+
+public class GitTree {
+
+ static public String cwd() {
+ return Paths.get(".").toAbsolutePath().normalize().toString();
+ }
+
+ static public String repo() {
+ return Paths.get(cwd(), ".m_git").toString();
+ }
+
+ static public String index() {
+ return Paths.get(repo(), "index").toString();
+ }
+
+ static public String log() {
+ return Paths.get(repo(), "logs").toString();
+ }
+
+ static public String storage() {
+ return Paths.get(repo(), "storage").toString();
+ }
+
+ static public String head() {
+ return Paths.get(repo(), "HEAD").toString();
+ }
+
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/util/HeadInfo.java b/task1_git/src/main/java/ru/ifmo/git/util/HeadInfo.java
new file mode 100644
index 0000000..88bb53f
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/util/HeadInfo.java
@@ -0,0 +1,25 @@
+package ru.ifmo.git.util;
+
+public class HeadInfo {
+
+ public String branchName;
+ public String headHash;
+ public String currentHash;
+
+ public HeadInfo() {
+ }
+
+ public HeadInfo(String branch) {
+ branchName = branch;
+ headHash = "";
+ currentHash = "";
+ }
+
+ public void setHeadHash(String hash) {
+ headHash = hash;
+ }
+
+ public void setCurrentHash(String hash) {
+ currentHash = hash;
+ }
+}
diff --git a/task1_git/src/main/java/ru/ifmo/git/util/Message.java b/task1_git/src/main/java/ru/ifmo/git/util/Message.java
new file mode 100644
index 0000000..3ef5ac4
--- /dev/null
+++ b/task1_git/src/main/java/ru/ifmo/git/util/Message.java
@@ -0,0 +1,34 @@
+package ru.ifmo.git.util;
+
+import java.io.*;
+import java.nio.charset.StandardCharsets;
+
+public class Message {
+
+ private ByteArrayOutputStream os;
+
+ public Message() {
+ os = new ByteArrayOutputStream();
+ }
+
+ public Message(String text) {
+ os = new ByteArrayOutputStream();
+ write(text);
+ }
+
+ public void write(String text) {
+ try (Writer writer = new OutputStreamWriter(os, StandardCharsets.UTF_8)) {
+ writer.write(text);
+ } catch (IOException ignored) {
+ }
+ }
+
+ public String read() {
+ return os.toString();
+ }
+
+ public void clear() {
+ os.reset();
+ }
+
+}