From e8015e8a30e2604c9a21d43e374d099f8238620d Mon Sep 17 00:00:00 2001
From: Bert Gijsbers <gijsbers@science.uva.nl>
Date: Sun, 26 May 2024 17:02:50 +0200
Subject: [PATCH] Add a permanent history of commands to the address bar.

---
 src/aaddressbar.cc | 80 +++++++++++++++++++++++++++++++++++++++++++---
 src/aaddressbar.h  | 13 +++++++-
 2 files changed, 87 insertions(+), 6 deletions(-)

diff --git a/src/aaddressbar.cc b/src/aaddressbar.cc
index 2845d96b1..7b152eadf 100644
--- a/src/aaddressbar.cc
+++ b/src/aaddressbar.cc
@@ -12,6 +12,7 @@
 #include "default.h"
 #include <unistd.h>
 #include <errno.h>
+#include <sys/stat.h>
 #include <X11/keysym.h>
 #include "ywordexp.h"
 
@@ -19,12 +20,15 @@ AddressBar::AddressBar(IApp *app, YWindow *parent):
     YInputLine(parent, this),
     app(app),
     location(0),
+    restored(0),
     curdir(upath::cwd()),
     olddir(curdir)
 {
+    loadHistoryTimer->setTimer(500L, this, true);
 }
 
 AddressBar::~AddressBar() {
+    saveHistory();
 }
 
 bool AddressBar::handleKey(const XKeyEvent &key) {
@@ -67,6 +71,9 @@ void AddressBar::handleReturn(bool control) {
     if (line.nonempty()) {
         history.append(line);
         location = history.getCount();
+        if (saveHistoryTimer == nullptr) {
+            saveHistoryTimer->setTimer(minute(), this, true);
+        }
     }
     if (internal(line))
         return;
@@ -87,8 +94,10 @@ void AddressBar::handleReturn(bool control) {
     if (line.isEmpty())
         args.replace(control, nullptr);
     if (args[0]) {
-        upath cwd(upath::cwd());
-        bool change = (cwd != curdir);
+        bool change = false;
+        upath cwd;
+        if (curdir != null && curdir != (cwd = upath::cwd()))
+            change = true;
         if (change)
             curdir.chdir();
         app->runProgram(args[0], args.getCArray());
@@ -113,8 +122,10 @@ bool AddressBar::internal(mstring line) {
         if (strchr("$~", arg[0]))
             arg = upath(arg).expand();
         else if (arg == "-")
-            arg = olddir;
-        upath newdir((arg[0] == '/') ? upath(arg) : curdir + arg);
+            arg = (olddir != null) ? olddir.path() : upath::cwd();
+        upath newdir((arg[0] == '/') ? upath(arg) :
+                     (curdir != null) ? curdir + arg :
+                     upath(upath::cwd()) + arg);
         upath realdir = upath(newdir).real();
         if (realdir.isEmpty()) {
             arg.fmt("%s: %m", newdir.string());
@@ -124,7 +135,7 @@ bool AddressBar::internal(mstring line) {
             arg.fmt("%s: %m", realdir.string());
             return setText(arg, true), true;
         } else {
-            olddir = curdir;
+            olddir = (curdir != null) ? curdir : upath(upath::cwd());
             curdir = realdir;
             return setText(curdir, true), true;
         }
@@ -176,4 +187,63 @@ void AddressBar::inputEscape(YInputLine* input) {
 void AddressBar::inputLostFocus(YInputLine* input) {
 }
 
+bool AddressBar::handleTimer(YTimer* timer) {
+    if (timer == loadHistoryTimer) {
+        loadHistory();
+        loadHistoryTimer = null;
+    }
+    else if (timer == saveHistoryTimer) {
+        saveHistory();
+        saveHistoryTimer = null;
+    }
+    else {
+        return YInputLine::handleTimer(timer);
+    }
+    return false;
+}
+
+upath AddressBar::historyFile() {
+    return YApplication::getPrivConfFile("ahistory");
+}
+
+void AddressBar::loadHistory() {
+    upath path(historyFile());
+    FILE* fp = path.fopen("r");
+    if (fp) {
+        char buf[4096];
+        int n = 0;
+        while (fgets(buf, sizeof buf, fp))
+            ++n;
+        rewind(fp);
+        for (int i = saveLines; i < n && fgets(buf, sizeof buf, fp); ++i)
+            ;
+        for (int i = 0; i < saveLines && fgets(buf, sizeof buf, fp); ++i) {
+            char* nl = strchr(buf, '\n');
+            if (nl)
+                *nl = '\0';
+            history.insert(i, buf);
+            location++;
+            restored++;
+        }
+        fclose(fp);
+    }
+}
+
+void AddressBar::saveHistory() {
+    if (restored < history.getCount()) {
+        upath path(historyFile());
+        FILE* fp = path.fopen("w");
+        if (fp) {
+            fchmod(fileno(fp), 0600);
+            const int first = max(0, history.getCount() - saveLines);
+            for (int i = first; i < history.getCount(); ++i) {
+                fputs(history[i], fp);
+                fputc('\n', fp);
+            }
+            fclose(fp);
+            restored = history.getCount();
+        }
+    }
+}
+
 // vim: set sw=4 ts=4 et:
diff --git a/src/aaddressbar.h b/src/aaddressbar.h
index 94e8500f3..6284e507c 100644
--- a/src/aaddressbar.h
+++ b/src/aaddressbar.h
@@ -6,7 +6,10 @@
 
 class IApp;
 
-class AddressBar: public YInputLine, private YInputListener {
+class AddressBar:
+    public YInputLine,
+    private YInputListener
+{
 public:
     AddressBar(IApp *app, YWindow *parent = nullptr);
     virtual ~AddressBar();
@@ -22,15 +25,23 @@ class AddressBar: public YInputLine, private YInputListener {
     void handleReturn(bool control);
     bool appendCommand(const char* cmd, class YStringArray& args);
     bool internal(mstring line);
+    void loadHistory();
+    void saveHistory();
+    upath historyFile();
 
     void inputReturn(YInputLine* input, bool control);
     void inputEscape(YInputLine* input);
     void inputLostFocus(YInputLine* input);
+    bool handleTimer(YTimer* timer);
 
     IApp *app;
     MStringArray history;
     int location;
+    int restored;
+    const int saveLines = 64;
     upath curdir, olddir;
+    lazy<YTimer> loadHistoryTimer;
+    lazy<YTimer> saveHistoryTimer;
 };
 
 #endif