From dd43119332c64c7a7f63c1a33b61d4dcd9f9fb4d Mon Sep 17 00:00:00 2001
From: =?utf8?q?Vin=C3=ADcius=20R=2E=20Miguel?= <lemao.vrm07@hotmail.com>
Date: Thu, 4 Jun 2020 01:58:47 -0300
Subject: [PATCH] Add history

---
 Headers/opsys.h   |  5 ++++-
 Sources/input.cpp | 13 +++++++++++--
 Sources/opsys.cpp | 25 +++++++++++++++++++++----
 3 files changed, 36 insertions(+), 7 deletions(-)

diff --git a/Headers/opsys.h b/Headers/opsys.h
index 94c49ff..0464b39 100644
--- a/Headers/opsys.h
+++ b/Headers/opsys.h
@@ -26,14 +26,17 @@ public:
 class OpSys
 {
     string get_cwd();
+    vector<vector<string>> history;
 public:
     string username;        // Username
     string hostname;        // User's hostname
     string cwd;             // Current working directory
     OpSys();
-    void change_dir(vector<string>);
+    void  change_dir(vector<string>);
+    void  show_history();
     short simple_command(vector<string>);
     short piped_command (vector<string>, int);
+    friend class Prompt;
 };
 
 extern OpSys OS;
diff --git a/Sources/input.cpp b/Sources/input.cpp
index dfff7c6..f182baa 100644
--- a/Sources/input.cpp
+++ b/Sources/input.cpp
@@ -87,10 +87,14 @@ void Prompt::parse(string input)
 short int Prompt::run()
 {
     string pipe = "|";
+
+        // Counts occurrences of a pipe character in the given command
     int pipe_count = std::count(tokens.begin(), tokens.end(), pipe);
 
+    OS.history.push_back(tokens);   // Save the current command on OS.history
+
     if(pipe_count)
-    {       // Checks if there's any pipe in the given command
+    {       // If there were pipes on the command, run OS.piped_command();
         return OS.piped_command(tokens, pipe_count);
     }
     if(!tokens[0].compare("cd"))
@@ -105,7 +109,12 @@ short int Prompt::run()
     {
         cout << "Insert help text here.\n";
         return 1;
-    } else if (!tokens[0].compare("quit"))
+    } else if (!tokens[0].compare("history"))
+    {
+        OS.show_history();
+        return 1;
+    }
+    else if (!tokens[0].compare("quit"))
     {
         std::cerr << "Exiting.\n";
         exit_program = true;
diff --git a/Sources/opsys.cpp b/Sources/opsys.cpp
index 37f9ed2..b2319b6 100644
--- a/Sources/opsys.cpp
+++ b/Sources/opsys.cpp
@@ -99,7 +99,7 @@ short OpSys::piped_command(vector<string> tokens, int pipe_count)
     for(i=0; i < n_commands; i++)
     {
         if (n_commands > 10)
-        {
+        {               // This is an arbitrary decision. Allowing for more pipes is easily possible.
             cerr << "More pipes than supported.\n";
             return -1;
         }
@@ -107,12 +107,13 @@ short OpSys::piped_command(vector<string> tokens, int pipe_count)
         for(;j<tokens.size();)
         {
             if (!tokens[j].compare(pipe_str))
-            {
-                j++;
+            {               //  We've hit a pipe character.
+                j++;        //  Skip a position for the next iteration.
                 break;
             }
             else
-            {
+            {               /*  Current token is not a pipe character
+                             *  so let's add it to our auxiliary command vector */
                 aux_cmd.push_back(tokens[j++]);
             }
         }
@@ -166,6 +167,22 @@ short OpSys::piped_command(vector<string> tokens, int pipe_count)
     return 1;
 }
 
+void OpSys::show_history()              // TODO: save (and read) history on a file? use Bourne Again's history??
+{
+    unsigned short i = 0, j;
+    for(vector<string> command : history)
+    {
+        string command_str = "";
+        for(j=0; j<command.size()-1; j++)
+        {
+            command_str += command[j] + ' ';
+        }
+        command_str += command.back();
+        printf("%-20hu\t%s\n", i++,  command_str.c_str());       // You may think this is unoptimized... which would actually be quite true.
+    }
+    fflush(stdout);
+}
+
 short OpSys::simple_command(vector<string> tokens)
 {
     int status;
-- 
2.11.4.GIT