From 3ce41848366007c132fffab51eeb8ecc21dcfc06 Mon Sep 17 00:00:00 2001
From: Jamie Reece Wilson <me@reece.sx>
Date: Thu, 22 Aug 2024 19:32:24 +0100
Subject: [PATCH] [+] AuCodepointsStartsWithEqualIgnoreCase [+]
 AuCodepointsEndsWithEqualIgnoreCase [+] AuCodepointsReverseIterate [+]
 AuCodepointsReverseIterateSubStrPrefixView [+]
 AuCodepointsReverseIterateSubStrSuffixView [+] AuROString::stl_remove_suffix
 [+] AuROString::stl_remove_prefix

---
 Include/auROXTL/auStringUtils.hpp    | 165 ++++++++++++++++++++++++++-
 Include/auROXTL/auUTF8StringView.hpp |  42 ++++++-
 2 files changed, 202 insertions(+), 5 deletions(-)

diff --git a/Include/auROXTL/auStringUtils.hpp b/Include/auROXTL/auStringUtils.hpp
index d5caa1e..40ff96a 100644
--- a/Include/auROXTL/auStringUtils.hpp
+++ b/Include/auROXTL/auStringUtils.hpp
@@ -19,7 +19,8 @@
                 AuCodepointsContains,
                 AuCodepointsReplaceAll, AuCodepointsSplitString (views),
                 AuCodepointsFindPreviousValidByteOffsetFromOffset, AuCodepointsFindPreviousValidByteOffsetFromByteOffset
-                AuCodepointsIsEqualIgnoreCase
+                AuCodepointsIsEqualIgnoreCase, AuCodepointsStartsWithEqualIgnoreCase, AuCodepointsEndsWithEqualIgnoreCase,
+                AuCodepointsReverseIterate, AuCodepointsReverseIterateSubStrPrefixView, AuCodepointsReverseIterateSubStrSuffixView
 
     For translating between locales (including utf8-32), defer to AuLocale (Aurora::Locale) in the Aurora Runtime.
 ***/
@@ -1307,6 +1308,168 @@ static CodepointOffset_t AuCodepointsFindCodepointOffset(const AuROString &in,
     return AuROString::npos;
 }
 
+static bool AuCodepointsStartsWithEqualIgnoreCase(const AuROString &inA,
+                                                  const AuROString &inB)
+{
+    if (inA.size() < inB.size())
+    {
+        return false;
+    }
+
+    if (inA.empty() ||
+        inB.empty())
+    {
+        return true;
+    }
+
+    const char *pItr  = inA.data();
+    const char *pItr2 = inB.data();
+    const char *pEnd  = pItr + inB.length();
+
+    while (pItr < pEnd)
+    {
+        AuUInt32 c {};
+
+        if ((c = *pItr) <= 0x7FU)
+        {
+            if (AuToLower(c) != AuToLower(*pItr2))
+            {
+                return false;
+            }
+            ++pItr2;
+            ++pItr;
+        }
+        else
+        {
+            AuUInt32 nby {};
+
+            if ((*pItr & 0xC0U) != 0xC0U)
+            {
+                return AuMemcmp(pItr, pItr2, pEnd - pItr) == 0;
+            }
+
+            for (AuUInt8 b = *pItr; (b & 0x80U) != 0; b <<= 1, ++nby)
+            {
+            }
+
+            if (nby > kAuCodepointUTF8MaxBytes)
+            {
+                return AuMemcmp(pItr, pItr2, pEnd - pItr) == 0;
+            }
+
+            if (AuUInt(pEnd - pItr) < AuUInt(nby))
+            {
+                return AuMemcmp(pItr, pItr2, pEnd - pItr) == 0;
+            }
+
+            if (AuMemcmp(pItr, pItr2, nby) != 0)
+            {
+                return false;
+            }
+
+            pItr  += nby;
+            pItr2 += nby;
+        }
+    }
+
+    return true;
+}
+
+static bool AuCodepointsEndsWithEqualIgnoreCase(const AuROString &inA,
+                                                const AuROString &inB)
+{
+    if (inA.size() < inB.size())
+    {
+        return false;
+    }
+
+    if (inA.empty() ||
+        inB.empty())
+    {
+        return true;
+    }
+    
+    AuUInt uOffset  { inA.Size() };
+    AuUInt uOffset2 { inB.Size() };
+
+    while (uOffset && uOffset2)
+    {
+        AuUInt32 c {};
+
+        auto uLastValid = AuCodepointsFindPreviousValidByteOffsetFromByteOffset(inB, uOffset2);
+        if (uLastValid == AuROString::npos)
+        {
+            return false;
+        }
+
+        auto nby      = uOffset2 - uLastValid;
+
+        if (AuSInt(uOffset) - AuSInt(nby) < 0)
+        {
+            return false;
+        }
+
+        auto pItr  = inA.data() + uOffset  - nby;
+        auto pItr2 = inB.data() + uOffset2 - nby;
+
+        if ((c = *pItr) <= 0x7FU)
+        {
+            if (AuToLower(c) != AuToLower(*pItr2))
+            {
+                return false;
+            }
+
+            uOffset  -= 1;
+            uOffset2 -= 1;
+        }
+        else
+        {
+            if (AuMemcmp(pItr, pItr2, nby) != 0)
+            {
+                return false;
+            }
+
+            uOffset  -= nby;
+            uOffset2 -= nby;
+        }
+    }
+
+    return true;
+}
+
+static AuUInt AuCodepointsReverseIterate(const AuROString &string)
+{
+    auto uLastValid = AuCodepointsFindPreviousValidByteOffsetFromByteOffset(string, string.Size());
+    if (uLastValid == AuROString::npos)
+    {
+        return AuROString::npos;
+    }
+
+    return string.Size() - uLastValid;
+}
+
+static AuROString AuCodepointsReverseIterateSubStrPrefixView(const AuROString &string)
+{
+    auto uOffset = AuCodepointsReverseIterate(string);
+    if (uOffset == AuROString::npos)
+    {
+        return AuROString {};
+    }
+
+    return string.RemoveSuffix(uOffset);
+}
+
+static AuROString AuCodepointsReverseIterateSubStrSuffixView(const AuROString &string)
+{
+    auto uLastValid = AuCodepointsFindPreviousValidByteOffsetFromByteOffset(string, string.Size());
+    if (uLastValid == AuROString::npos)
+    {
+        return AuROString {};
+    }
+
+    return string.RemovePrefix(uLastValid);
+}
+
 static bool AuCodepointsContains(const AuROString &value, const AuROString &subpattern, CodepointOffset_t uStartPosition = {})
 {
     return AuCodepointsFindCodepointOffset(value, subpattern, uStartPosition) != AuROString::npos;
diff --git a/Include/auROXTL/auUTF8StringView.hpp b/Include/auROXTL/auUTF8StringView.hpp
index 8f14ebb..9ee9380 100644
--- a/Include/auROXTL/auUTF8StringView.hpp
+++ b/Include/auROXTL/auUTF8StringView.hpp
@@ -155,7 +155,31 @@ struct AuROString
         return AuROString { this->pPointer + pos1, count1 };
     }
 
-    inline constexpr AuROString remove_suffix(size_type n)
+    inline constexpr void stl_remove_suffix(size_type n)
+    {
+        if (this->uLength < n)
+        {
+            *this = AuROString { };
+        }
+        else
+        {
+            *this = AuROString { this->pPointer, this->uLength - n };
+        }
+    }
+
+    inline constexpr void stl_remove_prefix(size_type n)
+    {
+        if (this->uLength < n)
+        {
+            *this = AuROString { };
+        }
+        else
+        {
+            *this = AuROString { this->pPointer + n, this->uLength - n };
+        }
+    }
+
+    inline constexpr AuROString remove_suffix(size_type n) const
     {
         if (this->uLength < n)
         {
@@ -165,7 +189,7 @@ struct AuROString
         return AuROString { this->pPointer, this->uLength - n };
     }
 
-    inline constexpr AuROString remove_prefix(size_type n)
+    inline constexpr AuROString remove_prefix(size_type n) const
     {
         if (this->uLength < n)
         {
@@ -175,12 +199,12 @@ struct AuROString
         return AuROString { this->pPointer + n, this->uLength - n };
     }
 
-    inline constexpr AuROString RemoveSuffix(size_type n)
+    inline constexpr AuROString RemoveSuffix(size_type n) const
     {
         return remove_suffix(n);
     }
 
-    inline constexpr AuROString RemovePrefix(size_type n)
+    inline constexpr AuROString RemovePrefix(size_type n) const
     {
         return remove_prefix(n);
     }
@@ -520,6 +544,11 @@ struct AuROString
         return this->substr(pos1, count1);
     }
 
+    inline constexpr AuROString SubStr(size_type pos1, size_type count1 = npos) const noexcept
+    {
+        return this->substr(pos1, count1);
+    }
+
     inline constexpr int Compare(basic_string_view v) const noexcept
     {
         return this->compare(v);
@@ -1201,6 +1230,11 @@ struct AuRONString
         return this->substr(pos1, count1);
     }
 
+    inline constexpr AuROString SubStr(size_type pos1, size_type count1 = npos) const noexcept
+    {
+        return this->substr(pos1, count1);
+    }
+
     inline constexpr int Compare(AuROString v) const noexcept
     {
         return this->compare(v);