From 83eb7d861edf57a432ed69127b7dbd945cd3cec0 Mon Sep 17 00:00:00 2001
From: Ismo Vuorinen <ismo@ivuorinen.net>
Date: Wed, 12 Jul 2023 22:44:08 +0300
Subject: [PATCH] feat(tools): sha256-matcher, cheat script tweaks

---
 local/bin/x-sha256sum-matcher          | 50 ++++++++++++++++++++++++++
 scripts/install-cheat-purebashbible.sh |  6 ++--
 scripts/install-cheat-tldr.sh          |  6 ++--
 scripts/shared.sh                      | 39 ++++++++++++++++++++
 4 files changed, 97 insertions(+), 4 deletions(-)
 create mode 100755 local/bin/x-sha256sum-matcher

diff --git a/local/bin/x-sha256sum-matcher b/local/bin/x-sha256sum-matcher
new file mode 100755
index 0000000..bd049f5
--- /dev/null
+++ b/local/bin/x-sha256sum-matcher
@@ -0,0 +1,50 @@
+#!/usr/bin/env bash
+# x-sha256sum-matcher
+#
+# Check if two files are the same
+#
+# Ismo Vuorinen <https://github.com/ivuorinen> 2023
+# MIT License
+
+# ENV Variables
+: "${VERBOSE:=0}" # VERBOSE=1 x-sha256sum-matcher file1 file2
+
+file_1="$1"
+file_2="$2"
+
+# return sha256sum for file
+# $1 - filename (string)
+get_sha256sum() {
+  sha256sum "$1" | head -c 64
+}
+
+[ $# -eq 0 ] && {
+  echo "Usage: $0 file1.sh file2.sh" && exit 1
+}
+
+msg() {
+  [[ "$VERBOSE" -eq 1 ]] && echo "$1"
+}
+
+error() {
+  msg "(!) ERROR: $1" && exit 1
+}
+
+if [ ! -f "$file_1" ]; then
+  error "File 1 does not exist: $file_1"
+fi
+
+if [ ! -f "$file_2" ]; then
+  error "File 2 does not exist: $file_2"
+fi
+
+file_1_hash=$(get_sha256sum "$file_1")
+file_2_hash=$(get_sha256sum "$file_2")
+
+if [ "$file_1_hash" != "$file_2_hash" ]; then
+  error "Files do not match"
+else
+  msg "(*) Success: Files do match"
+  exit 0;
+fi
+
diff --git a/scripts/install-cheat-purebashbible.sh b/scripts/install-cheat-purebashbible.sh
index 5c1d7df..43c9a7d 100755
--- a/scripts/install-cheat-purebashbible.sh
+++ b/scripts/install-cheat-purebashbible.sh
@@ -35,8 +35,10 @@ for f in ${PBB_CHAPTERS[@]}; do
   HEADER=$(grep -e '^[#] ' "$f" | head -1 | awk '{print tolower($2)}')
   CHEAT_FILE="$CHEAT_DEST/${HEADER}"
 
-  if [ ! -f "$CHEAT_FILE" ]; then
-    cp "$f" "$CHEAT_FILE" && msg_run "$CHEAT_FILE"
+  replacable "$f" "$CHEAT_FILE"
+  override=$?
+  if [ "$override" -ne 1 ]; then
+    cp "$f" "$CHEAT_FILE" && msg_run "Updated: $CHEAT_FILE"
   fi
 
   LC_ALL=C perl -pi.bak -e 's/\<\!-- CHAPTER END --\>//' "$CHEAT_FILE"
diff --git a/scripts/install-cheat-tldr.sh b/scripts/install-cheat-tldr.sh
index c02d2f4..2d2968f 100755
--- a/scripts/install-cheat-tldr.sh
+++ b/scripts/install-cheat-tldr.sh
@@ -51,8 +51,10 @@ for d in "$TLDR_TEMP_DIR"/pages/*; do
     TLDR_FILE="$SECTION_DIR/${FILENAME}"
     # echo "-> dest: $TLDR_FILE"
 
-    if [ ! -f "$TLDR_FILE" ]; then
-      cp "$FILE" "$TLDR_FILE" && msg_run "$TLDR_FILE"
+    replacable "$FILE" "$TLDR_FILE"
+    override=$?
+    if [ "$override" -ne 1 ]; then
+      cp "$FILE" "$TLDR_FILE" && msg_run "Updated: $TLDR_FILE"
     fi
 
     if [ -f "$TLDR_FILE" ] && [ '---' != "$(head -1 < "$TLDR_FILE")" ]; then
diff --git a/scripts/shared.sh b/scripts/shared.sh
index 41bc00b..f6e31d6 100755
--- a/scripts/shared.sh
+++ b/scripts/shared.sh
@@ -230,3 +230,42 @@ rnd()
 {
   echo $RANDOM | md5sum | head -c 20
 }
+
+# return sha256sum for file
+# $1 - filename (string)
+function get_sha256sum()
+{
+  sha256sum "$1" | head -c 64
+}
+
+# Replacable file
+#
+# $1 - filename (string)
+# $2 - filename (string)
+#
+# Returns 1 when replacable, 0 when not replacable.
+function replacable()
+{
+  FILE1="$1"
+  FILE2="$2"
+
+  [[ ! -r "$FILE1" ]] && { msg_err "File 1 ($FILE1) does not exist" && return 1; }
+  [[ ! -r "$FILE2" ]] && { msg_err "File 2 ($FILE2) does not exist" && return 1; }
+
+  FILE1_HASH=$(get_sha256sum "$FILE1")
+  FILE2_HASH=$(get_sha256sum "$FILE2")
+
+  [[ $FILE1_HASH = "" ]] && {
+    msg_err "Could not get hash for file 1 ($FILE1)" && return 1;
+  }
+  [[ $FILE2_HASH = "" ]] && {
+    msg_err "Could not get hash for file 2 ($FILE2)" && return 1;
+  }
+
+  [[ "$FILE1_HASH" == "$FILE2_HASH" ]] && {
+    msg_ok "Files match, not replacable" && return 0;
+  }
+
+  return 1;
+}
+