From e73440918709cf7b496db21883a4cf90b8e129f7 Mon Sep 17 00:00:00 2001
From: nick black <dankamongmen@gmail.com>
Date: Thu, 24 Jun 2021 07:52:05 -0400
Subject: [PATCH] implement NCOPTION_PRESERVE_CURSOR #1823

---
 src/lib/direct.c    |  2 +-
 src/lib/input.c     | 15 +++++++++++----
 src/lib/notcurses.c |  8 +++++++-
 src/lib/termdesc.c  | 19 +++++++++++--------
 src/lib/termdesc.h  |  3 ++-
 5 files changed, 32 insertions(+), 15 deletions(-)

diff --git a/src/lib/direct.c b/src/lib/direct.c
index b966bea3a..3734083dc 100644
--- a/src/lib/direct.c
+++ b/src/lib/direct.c
@@ -825,7 +825,7 @@ ncdirect* ncdirect_core_init(const char* termtype, FILE* outfp, uint64_t flags){
   shortname_term = termname();
   if(interrogate_terminfo(&ret->tcache, ret->ctermfd, shortname_term, utf8,
                           1, flags & NCDIRECT_OPTION_INHIBIT_CBREAK,
-                          TERMINAL_UNKNOWN)){
+                          TERMINAL_UNKNOWN, NULL, NULL)){
     goto err;
   }
   if(ncvisual_init(NCLOGLEVEL_SILENT)){
diff --git a/src/lib/input.c b/src/lib/input.c
index a28ec0045..b045e1d9c 100644
--- a/src/lib/input.c
+++ b/src/lib/input.c
@@ -884,6 +884,9 @@ pump_control_read(query_state* inits, unsigned char c){
         inits->state = STATE_SDA;
       }else if(isdigit(c)){
         inits->numeric = 0;
+        if(ruts_numeric(&inits->numeric, c)){
+          return -1;
+        }
         inits->state = STATE_CURSOR;
       }else if(c >= 0x40 && c <= 0x7E){
         inits->state = STATE_NULL;
@@ -891,7 +894,7 @@ pump_control_read(query_state* inits, unsigned char c){
       break;
     case STATE_CURSOR:
       if(isdigit(c)){
-        if(ruts_hex(&inits->numeric, c)){
+        if(ruts_numeric(&inits->numeric, c)){
           return -1;
         }
       }else if(c == ';'){
@@ -904,7 +907,7 @@ pump_control_read(query_state* inits, unsigned char c){
       break;
     case STATE_CURSOR_COL:
       if(isdigit(c)){
-        if(ruts_hex(&inits->numeric, c)){
+        if(ruts_numeric(&inits->numeric, c)){
           return -1;
         }
       }else if(c == 'R'){
@@ -1231,8 +1234,12 @@ int ncinputlayer_init(tinfo* tcache, FILE* infp, queried_terminals_e* detected,
       tcache->termversion = inits.version;
       *detected = inits.qterm;
       *appsync = inits.appsync;
-      *cursor_x = inits.cursor_x;
-      *cursor_y = inits.cursor_y;
+      if(cursor_x){
+        *cursor_x = inits.cursor_x - 1;
+      }
+      if(cursor_y){
+        *cursor_y = inits.cursor_y - 1;
+      }
     }
   }
   return 0;
diff --git a/src/lib/notcurses.c b/src/lib/notcurses.c
index f0505f8c2..1f4cf41cc 100644
--- a/src/lib/notcurses.c
+++ b/src/lib/notcurses.c
@@ -1097,9 +1097,12 @@ notcurses* notcurses_core_init(const notcurses_options* opts, FILE* outfp){
   }
   const char* shortname_term = termname();
 // const char* longname_term = longname();
+  int cursor_y, cursor_x;
   if(interrogate_terminfo(&ret->tcache, ret->ttyfd, shortname_term, utf8,
                           opts->flags & NCOPTION_NO_ALTERNATE_SCREEN, 0,
-                          detected_term)){
+                          detected_term,
+                          opts->flags & NCOPTION_PRESERVE_CURSOR ? &cursor_y : NULL,
+                          opts->flags & NCOPTION_PRESERVE_CURSOR ? &cursor_x : NULL)){
     goto err;
   }
   int dimy, dimx;
@@ -1119,6 +1122,9 @@ notcurses* notcurses_core_init(const notcurses_options* opts, FILE* outfp){
     fprintf(stderr, "Couldn't create the initial plane (bad margins?)\n");
     goto err;
   }
+  if(cursor_y >= 0 && cursor_x >= 0){
+    ncplane_cursor_move_yx(ret->stdplane, cursor_y, cursor_x);
+  }
   if(ret->ttyfd >= 0){
     reset_term_attributes(&ret->tcache, ret->ttyfp);
     if(!(opts->flags & NCOPTION_NO_CLEAR_BITMAPS)){
diff --git a/src/lib/termdesc.c b/src/lib/termdesc.c
index af362f58a..6f088827c 100644
--- a/src/lib/termdesc.c
+++ b/src/lib/termdesc.c
@@ -334,7 +334,8 @@ apply_term_heuristics(tinfo* ti, const char* termname, int fd,
 // full round trip before getting the reply, which is likely to pace init.
 int interrogate_terminfo(tinfo* ti, int fd, const char* termname, unsigned utf8,
                          unsigned noaltscreen, unsigned nocbreak,
-                         queried_terminals_e qterm){
+                         queried_terminals_e qterm,
+                         int* cursor_y, int* cursor_x){
   memset(ti, 0, sizeof(*ti));
   if(fd >= 0){
     if(qterm == TERMINAL_UNKNOWN){
@@ -504,9 +505,10 @@ int interrogate_terminfo(tinfo* ti, int fd, const char* termname, unsigned utf8,
     }
   }
   unsigned appsync_advertised;
-  int cursor_x = -1;
-  int cursor_y = -1;
-  if(ncinputlayer_init(ti, stdin, &qterm, &appsync_advertised, &cursor_y, &cursor_x)){
+  if(cursor_x && cursor_y){
+    *cursor_x = *cursor_y = 0;
+  }
+  if(ncinputlayer_init(ti, stdin, &qterm, &appsync_advertised, cursor_y, cursor_x)){
     goto err;
   }
   if(nocbreak){
@@ -517,11 +519,12 @@ int interrogate_terminfo(tinfo* ti, int fd, const char* termname, unsigned utf8,
       }
     }
   }
-  if(cursor_x >= 0 && cursor_y >= 0){
-    if(add_u7_escape(ti, &tablelen, &tableused)){
-      return -1;
+  if(cursor_x && cursor_y){
+    if(*cursor_x >= 0 && *cursor_y >= 0){
+      if(add_u7_escape(ti, &tablelen, &tableused)){
+        return -1;
+      }
     }
-    // FIXME set cursor up
   }
   if(appsync_advertised){
     if(add_appsync_escapes(ti, &tablelen, &tableused)){
diff --git a/src/lib/termdesc.h b/src/lib/termdesc.h
index 78de1a479..1831eb3ab 100644
--- a/src/lib/termdesc.h
+++ b/src/lib/termdesc.h
@@ -185,7 +185,8 @@ term_supported_styles(const tinfo* ti){
 // TERMINAL_UNKNOWN.
 int interrogate_terminfo(tinfo* ti, int fd, const char* termname, unsigned utf8,
                          unsigned noaltscreen, unsigned nocbreak,
-                         queried_terminals_e qterm);
+                         queried_terminals_e qterm,
+                         int* cursor_y, int* cursor_x);
 
 void free_terminfo_cache(tinfo* ti);