From 0a61197cb6b062db198c1a119fee220f3863dd18 Mon Sep 17 00:00:00 2001
From: Garritt McCune <glmccune@gmail.com>
Date: Tue, 5 Jul 2022 19:32:58 -0500
Subject: [PATCH] Added a way to delete a range of characters at any index and
 count.

---
 main.c    | 15 +++++++++++++++
 tstring.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
 tstring.h |  1 +
 3 files changed, 65 insertions(+)

diff --git a/main.c b/main.c
index edb90d4..dda35e3 100644
--- a/main.c
+++ b/main.c
@@ -58,6 +58,21 @@ int main(int argc, char** argv) {
         }
 
         if (input[0] == 'r') {
+            if (input[1] != '\0') {
+                printf("Select index: ");
+                fgets(input, sizeof input, stdin);
+            
+                int num = strtol(input, NULL, 10);
+                printf("Enter count: ");
+
+                fgets(input, sizeof input, stdin);
+
+                int count = strtol(input, NULL, 10);
+
+                TStringRemoveRange(num, count, string);
+
+                continue;
+            }
             TStringPop(glyph, string);
             printf("Popped '%s'\n", glyph);
             continue;
diff --git a/tstring.c b/tstring.c
index 0fd8f37..20ccfd5 100644
--- a/tstring.c
+++ b/tstring.c
@@ -5,6 +5,7 @@
 #include <errno.h>
 
 void TStringCopyGlyph(const char* glyph, int length, TString* string);
+void TStringCompactString(unsigned int startByte, unsigned int endByte, TString* string);
 int ResizeTStringCapacity(int newTextLength, TString* string);
 int GetGlyphByteWidth(char glyph);
 
@@ -91,6 +92,50 @@ void TStringPop(char buffer[8], TString* string) {
     }
 }
 
+void TStringRemoveRange(int startIndex, int count, TString* string) {
+    if (!string) return;
+    if (startIndex < 0 || startIndex > string->Length) return;
+    if (count <= 0 || count > string->Length - startIndex) return;
+
+    char buffer[256] = { 0 };
+    unsigned int startByte = 0;
+    unsigned int glyphCount = 0;
+
+    while(glyphCount != startIndex) {
+        startByte += GetGlyphByteWidth(string->Characters[startByte]);
+
+        glyphCount++;
+    }
+
+    unsigned int endByte = startByte;
+
+    for (glyphCount = 0; glyphCount < count; glyphCount++) endByte += GetGlyphByteWidth(string->Characters[endByte]);
+
+    memset(&string->Characters[startByte], '\0', endByte - startByte);
+
+    if (endByte == string->ByteCount) {
+        string->Length -= glyphCount;
+        string->ByteCount -= endByte - startByte;
+        return;
+    }
+
+    unsigned int fullBuffers = (string->ByteCount - endByte) / sizeof buffer;
+    unsigned int remainder = (string->ByteCount - endByte) - fullBuffers * sizeof buffer;
+
+    for (int i = fullBuffers; i > 0; i--) {
+        memcpy(buffer, &string->Characters[string->ByteCount - i * sizeof buffer], sizeof buffer);
+        memcpy(&string->Characters[endByte - sizeof buffer * i], buffer, sizeof buffer);
+    }
+
+    if (remainder > 0) {
+        memcpy(buffer, &string->Characters[endByte], remainder);
+        memcpy(&string->Characters[startByte], buffer, remainder);
+    }
+
+    string->Length -= glyphCount;
+    string->ByteCount -= endByte - startByte;
+}
+
 void TStringInsertText(const char* text, int index, TString* string) {
     if (!text || !string) return;
     if (index < 0 || index > string->Length) index = string->Length;
@@ -124,6 +169,10 @@ void TStringInsertText(const char* text, int index, TString* string) {
     string->ByteCount += insertionTextLength;
 }
 
+void TStringCompactString(unsigned int startByte, unsigned int endByte, TString* string) {
+
+}
+
 void TStringAppendText(const char* text, TString* string) {
     if (!text || !string) return;
 
diff --git a/tstring.h b/tstring.h
index 7c549f9..6e8e33d 100644
--- a/tstring.h
+++ b/tstring.h
@@ -14,6 +14,7 @@ void TStringFree(TString* string);
 void TStringPrintDetails(const TString* string, int statsOnly);
 void TStringInsertText(const char* text, int index, TString* string);
 void TStringPop(char buffer[8], TString* string);
+void TStringRemoveRange(int startIndex, int count, TString* string);
 char* TStringGetString(const TString* string);
 int TStringLength(const TString* string);