From 879a26f3cf8b9b338e7dd6ecd31a039dfaa0c7ad Mon Sep 17 00:00:00 2001
From: "K. Lange" <klange@toaruos.org>
Date: Tue, 2 Aug 2022 10:16:57 +0900
Subject: [PATCH] Support rline in the simple-repl and update it to be more
 like the real one

---
 tools/sandbox.c     |  5 ++-
 tools/simple-repl.h | 77 +++++++++++++++++++++++++++++++++++++--------
 2 files changed, 66 insertions(+), 16 deletions(-)

diff --git a/tools/sandbox.c b/tools/sandbox.c
index 03b86aa..54a8bc4 100644
--- a/tools/sandbox.c
+++ b/tools/sandbox.c
@@ -7,8 +7,8 @@
 #include "simple-repl.h"
 
 int main(int argc, char * argv[]) {
-	/* Disable automatic traceback printing, default modules */
-	krk_initVM(KRK_GLOBAL_CLEAN_OUTPUT|KRK_GLOBAL_NO_DEFAULT_MODULES);
+	/* Disable default modules */
+	krk_initVM(KRK_GLOBAL_NO_DEFAULT_MODULES);
 
 	/* Set up our module context. */
 	krk_startModule("__main__");
@@ -29,7 +29,6 @@ int main(int argc, char * argv[]) {
 				fprintf(stdout, " => %s\n", AS_CSTRING(result));
 			}
 		} else if (krk_currentThread.flags & KRK_THREAD_HAS_EXCEPTION) {
-			krk_dumpTraceback();
 			retval = 1;
 		}
 	} else {
diff --git a/tools/simple-repl.h b/tools/simple-repl.h
index 80b7214..1a69b6c 100644
--- a/tools/simple-repl.h
+++ b/tools/simple-repl.h
@@ -1,7 +1,16 @@
+#ifdef SIMPLE_REPL_ENABLE_RLINE
+#include "vendor/rline.h"
+static int enableRline = 1;
+#endif
 
 #define PROMPT_MAIN  ">>> "
 #define PROMPT_BLOCK "  > "
+
 static int runSimpleRepl(void) {
+#ifdef _WIN32
+	SetConsoleOutputCP(65001);
+	SetConsoleCP(65001);
+#endif
 	int exitRepl = 0;
 	while (!exitRepl) {
 		size_t lineCapacity = 8;
@@ -12,20 +21,57 @@ static int runSimpleRepl(void) {
 		char * allData = NULL;
 		int inBlock = 0;
 		int blockWidth = 0;
+#ifdef SIMPLE_REPL_ENABLE_RLINE
+		rline_exp_set_prompts(PROMPT_MAIN, "", 4, 0);
+		rline_exit_string="";
+		rline_exp_set_syntax("krk");
+		rline_exp_set_tab_complete_func(NULL);
+#endif
 		while (1) {
 			/* This would be a nice place for line editing */
 			char buf[4096] = {0};
-			fprintf(stdout, "%s", inBlock ? PROMPT_BLOCK : PROMPT_MAIN);
-			fflush(stdout);
-
-			char * out = fgets(buf, 4096, stdin);
-			if (!out || !strlen(buf)) {
-				fprintf(stdout, "^D\n");
-				valid = 0;
-				exitRepl = 1;
-				break;
+#ifdef SIMPLE_REPL_ENABLE_RLINE
+			if (inBlock) {
+				/* When entering multiple lines, the additional lines
+				 * will show a single > (and keep the left side aligned) */
+				rline_exp_set_prompts(PROMPT_BLOCK, "", 4, 0);
+				/* Also add indentation as necessary */
+				rline_preload = malloc(blockWidth + 1);
+				for (int i = 0; i < blockWidth; ++i) {
+					rline_preload[i] = ' ';
+				}
+				rline_preload[blockWidth] = '\0';
 			}
 
+			if (!enableRline) {
+#else
+			if (1) {
+#endif
+				fprintf(stdout, "%s", inBlock ? PROMPT_BLOCK : PROMPT_MAIN);
+				fflush(stdout);
+			}
+
+#ifdef SIMPLE_REPL_ENABLE_RLINE
+			rline_scroll = 0;
+			if (enableRline) {
+				if (rline(buf, 4096) == 0) {
+					valid = 0;
+					exitRepl = 1;
+					break;
+				}
+			} else {
+#endif
+				char * out = fgets(buf, 4096, stdin);
+				if (!out || !strlen(buf)) {
+					fprintf(stdout, "^D\n");
+					valid = 0;
+					exitRepl = 1;
+					break;
+				}
+#ifdef SIMPLE_REPL_ENABLE_RLINE
+			}
+#endif
+
 			if (buf[strlen(buf)-1] != '\n') {
 				valid = 0;
 				break;
@@ -95,14 +141,21 @@ static int runSimpleRepl(void) {
 
 		for (size_t i = 0; i < lineCount; ++i) {
 			if (valid) strcat(allData, lines[i]);
+#ifdef SIMPLE_REPL_ENABLE_RLINE
+			if (enableRline) {
+				rline_history_insert(strdup(lines[i]));
+				rline_scroll = 0;
+			}
+#endif
 			free(lines[i]);
 		}
 		FREE_ARRAY(char *, lines, lineCapacity);
 		if (valid) {
 			KrkValue result = krk_interpret(allData, "<stdin>");
 			if (!IS_NONE(result)) {
+				krk_attachNamedValue(&vm.builtins->fields, "_", result);
 				KrkClass * type = krk_getType(result);
-				const char * formatStr = " \033[1;30m=> %s\033[0m\n";
+				const char * formatStr = " \033[1;90m=> %s\033[0m\n";
 				if (type->_reprer) {
 					krk_push(result);
 					result = krk_callDirect(type->_reprer, 1);
@@ -111,12 +164,10 @@ static int runSimpleRepl(void) {
 					result = krk_callDirect(type->_tostr, 1);
 				}
 				if (!IS_STRING(result)) {
-					fprintf(stdout, " \033[1;31m=> Unable to produce representation for value.\033[0m\n");
+					fprintf(stdout, " \033[1;91m=> Unable to produce representation for value.\033[0m\n");
 				} else {
 					fprintf(stdout, formatStr, AS_CSTRING(result));
 				}
-			} else if (krk_currentThread.flags & KRK_THREAD_HAS_EXCEPTION) {
-				krk_dumpTraceback();
 			}
 			krk_resetStack();
 			free(allData);