From 510c874061cd73ec95afcd26ab4f814463776d9e Mon Sep 17 00:00:00 2001
From: Keith Burzinski <kbx81x@gmail.com>
Date: Fri, 16 Jan 2026 19:23:41 -0600
Subject: [PATCH] [helpers] Remove `base85` functions (#13266)

---
 esphome/core/helpers.cpp | 49 ----------------------------------------
 esphome/core/helpers.h   |  8 -------
 2 files changed, 57 deletions(-)

diff --git a/esphome/core/helpers.cpp b/esphome/core/helpers.cpp
index 5cad2308df..5de1c70562 100644
--- a/esphome/core/helpers.cpp
+++ b/esphome/core/helpers.cpp
@@ -664,55 +664,6 @@ bool base64_decode_int32_vector(const std::string &base64, std::vector<int32_t>
   return !out.empty();
 }
 
-/// Encode int32 to 5 base85 characters + null terminator
-/// Standard ASCII85 alphabet: '!' (33) = 0 through 'u' (117) = 84
-inline void base85_encode_int32(int32_t value, std::span<char, BASE85_INT32_ENCODED_SIZE> output) {
-  uint32_t v = static_cast<uint32_t>(value);
-  // Encode least significant digit first, then reverse
-  for (int i = 4; i >= 0; i--) {
-    output[i] = static_cast<char>('!' + (v % 85));
-    v /= 85;
-  }
-  output[5] = '\0';
-}
-
-/// Decode 5 base85 characters to int32
-inline bool base85_decode_int32(const char *input, int32_t &out) {
-  uint8_t c0 = static_cast<uint8_t>(input[0] - '!');
-  uint8_t c1 = static_cast<uint8_t>(input[1] - '!');
-  uint8_t c2 = static_cast<uint8_t>(input[2] - '!');
-  uint8_t c3 = static_cast<uint8_t>(input[3] - '!');
-  uint8_t c4 = static_cast<uint8_t>(input[4] - '!');
-
-  // Each digit must be 0-84. Since uint8_t wraps, chars below '!' become > 84
-  if (c0 > 84 || c1 > 84 || c2 > 84 || c3 > 84 || c4 > 84)
-    return false;
-
-  // 85^4 = 52200625, 85^3 = 614125, 85^2 = 7225, 85^1 = 85
-  out = static_cast<int32_t>(c0 * 52200625u + c1 * 614125u + c2 * 7225u + c3 * 85u + c4);
-  return true;
-}
-
-/// Decode base85 string directly into vector (no intermediate buffer)
-bool base85_decode_int32_vector(const std::string &base85, std::vector<int32_t> &out) {
-  size_t len = base85.size();
-  if (len % 5 != 0)
-    return false;
-
-  out.clear();
-  const char *ptr = base85.data();
-  const char *end = ptr + len;
-
-  while (ptr < end) {
-    int32_t value;
-    if (!base85_decode_int32(ptr, value))
-      return false;
-    out.push_back(value);
-    ptr += 5;
-  }
-  return true;
-}
-
 // Colors
 
 float gamma_correct(float value, float gamma) {
diff --git a/esphome/core/helpers.h b/esphome/core/helpers.h
index 000762c9bf..0acc6bdc60 100644
--- a/esphome/core/helpers.h
+++ b/esphome/core/helpers.h
@@ -1143,14 +1143,6 @@ size_t base64_decode(const uint8_t *encoded_data, size_t encoded_len, uint8_t *b
 /// @return true if successful, false if decode failed or invalid size
 bool base64_decode_int32_vector(const std::string &base64, std::vector<int32_t> &out);
 
-/// Size of buffer needed for base85 encoded int32 (5 chars + null terminator)
-static constexpr size_t BASE85_INT32_ENCODED_SIZE = 6;
-
-void base85_encode_int32(int32_t value, std::span<char, BASE85_INT32_ENCODED_SIZE> output);
-
-bool base85_decode_int32(const char *input, int32_t &out);
-bool base85_decode_int32_vector(const std::string &base85, std::vector<int32_t> &out);
-
 ///@}
 
 /// @name Colors