From 00f230fcb2f0f574a293d7ffa715192f00f803bf Mon Sep 17 00:00:00 2001
From: Bananymous <bananymousosq@gmail.com>
Date: Tue, 13 Dec 2022 14:33:38 +0200
Subject: [PATCH] BAN: Add basic String implementation

---
 BAN/include/BAN/String.h | 184 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 184 insertions(+)
 create mode 100644 BAN/include/BAN/String.h

diff --git a/BAN/include/BAN/String.h b/BAN/include/BAN/String.h
new file mode 100644
index 000000000..2d0da4c9e
--- /dev/null
+++ b/BAN/include/BAN/String.h
@@ -0,0 +1,184 @@
+#pragma
+
+#include <BAN/Errors.h>
+#include <BAN/Formatter.h>
+#include <BAN/Memory.h>
+
+#include <assert.h>
+#include <string.h>
+#include <sys/param.h>
+
+namespace BAN
+{
+
+	class String
+	{
+	public:
+		using size_type = size_t;
+
+	public:
+		String() = default;
+		String(const char*);
+		~String();
+
+		ErrorOr<void> PushBack(char);
+		ErrorOr<void> Insert(char, size_type);
+		ErrorOr<void> Append(const char*);
+		ErrorOr<void> Append(const String&);
+		
+		void PopBack();
+		void Remove(size_type);
+
+		char operator[](size_type) const;
+		char& operator[](size_type);
+
+		ErrorOr<void> Resize(size_type, char = '\0');
+		ErrorOr<void> Reserve(size_type);
+
+		size_type Size() const;
+		size_type Capasity() const;
+
+		const char* Data() const;
+
+	private:
+		ErrorOr<void> EnsureCapasity(size_type);
+
+	private:
+		char*		m_data		= nullptr;
+		size_type	m_capasity	= 0;
+		size_type	m_size		= 0;	
+	};
+
+	String::String(const char* string)
+	{
+		size_type len = strlen(string);
+		MUST(EnsureCapasity(len + 1));
+		memcpy(m_data, string, len);
+		m_data[len] = '\0';
+		m_size = len;
+	}
+
+	String::~String()
+	{
+		BAN::deallocator(m_data);
+	}
+
+	ErrorOr<void> String::PushBack(char ch)
+	{
+		TRY(EnsureCapasity(m_size + 2));
+		m_data[m_size]		= ch;
+		m_data[m_size + 1]	= '\0';
+		m_size++;
+		return {};
+	}
+
+	ErrorOr<void> String::Insert(char ch, size_type index)
+	{
+		assert(index <= m_size);
+		TRY(EnsureCapasity(m_size + 2));
+		memmove(m_data + index + 1, m_data + index, m_size - index);
+		m_data[index]		= ch;
+		m_data[m_size + 1]	= '\0';
+		m_size++;
+		return {};
+	}
+
+	ErrorOr<void> String::Append(const char* string)
+	{
+		size_t len = strlen(string);
+		TRY(EnsureCapasity(m_size + len + 1));
+		memcpy(m_data + m_size, string, len);
+		m_data[m_size + len] = '\0';
+		m_size += len;
+		return {};
+	}
+
+	ErrorOr<void> String::Append(const String& string)
+	{
+		TRY(Append(string.Data()));
+		return {};
+	}
+
+	void String::PopBack()
+	{
+		assert(m_size > 0);
+		m_data[m_size - 1] = '\0';
+		m_size--;
+	}
+
+	void String::Remove(size_type index)
+	{
+		assert(index < m_size);
+		memmove(m_data + index, m_data + index + 1, m_size - index - 1);
+		m_data[m_size - 1] = '\0';
+		m_size--;
+	}
+	
+	char String::operator[](size_type index) const
+	{
+		assert(index < m_size);
+		return m_data[index];
+	}
+
+	char& String::operator[](size_type index)
+	{
+		assert(index < m_size);
+		return m_data[index];
+	}
+
+	ErrorOr<void> String::Resize(size_type size, char ch)
+	{
+		if (size < m_size)
+		{
+			m_data[size] = '\0';
+			m_size = size;
+		}
+		else if (size > m_size)
+		{
+			TRY(EnsureCapasity(size + 1));
+			for (size_type i = m_size; i < size; i++)
+				m_data[i] = ch;
+			m_data[size] = '\0';
+			m_size = size;
+		}
+		m_size = size;
+		return {};
+	}
+
+	ErrorOr<void> String::Reserve(size_type size)
+	{
+		TRY(EnsureCapasity(size + 1));
+		return {};
+	}
+
+	String::size_type String::Size() const
+	{
+		return m_size;
+	}
+
+	String::size_type String::Capasity() const
+	{
+		return m_capasity;
+	}
+
+	const char* String::Data() const
+	{
+		return m_data;
+	}
+
+	ErrorOr<void> String::EnsureCapasity(size_type size)
+	{
+		if (m_capasity >= size)
+			return {};
+		size_type new_cap = MAX(size, m_capasity * 1.5f);
+		void* new_data = BAN::allocator(new_cap);
+		if (new_data == nullptr)
+			return Error::FromString("String: Could not allocate memory");
+		memcpy(new_data, m_data, m_size + 1);
+		BAN::deallocator(m_data);
+		m_data = (char*)new_data;
+		m_capasity = new_cap;
+		return {};
+	}
+
+}
\ No newline at end of file