refactor(setup): idempotent symlinks/copies, diff flag, flat COPIES

setup.sh

@@ -15,6 +15,7 @@ PRINT_HELP=false
 FORCE=false
 REMOVE_EXISTING=false
 IGNORE_EXISTING=false
+DIFF=false
 ERROR=false
 
 # Define packages
@@ -77,8 +78,9 @@ SYMLINKS=(
 typeset -a COPIES
 COPIES=(
     ".codex/config.toml"
-    ".config/gtk-3.0"
-    ".config/gtk-4.0"
+    ".config/gtk-3.0/bookmarks"
+    ".config/gtk-3.0/settings.ini"
+    ".config/gtk-4.0/settings.ini"
     ".gtkrc-2.0"
 )
 
@@ -95,7 +97,7 @@ typeset -A SYMLINK_MAP
 SYMLINK_MAP[zsh/rc]=".zshrc"
 
 error() {
-    msg="$1"
+    local msg="$@"
     ERROR=true
     echo "Error: $msg" >&2
 }
@@ -117,10 +119,10 @@ remove_symlink() {
         echo "Removing symlink: $link -> $src"
         rm "$link"
     elif test -e "$link"; then
-        error "object to be removed is not a symlink:"
-        error "${link}: $(stat -c '%F' -- "$link")"
+        error "object to be removed is not a symlink:" \
+            "${link}: $(stat -c '%F' -- "$link")"
 
-        return 1
+        return 0
     fi
 }
 
@@ -141,14 +143,12 @@ create_symlink() {
     rel_dst="$2"
 
     if test -z "$rel_src"; then
-        error "missing src argument:"
-        error "$0 $@"
+        error "missing src argument: $0 $@"
         return 1
     fi
 
     if test -z "$rel_dst"; then
-        error "missing dst argument:"
-        error "$0 $@"
+        error "missing dst argument: $0 $@"
         return 1
     fi
 
@@ -157,8 +157,7 @@ create_symlink() {
     dst_parent="$(dirname -- "$dst")"
 
     if ! test -e "$src"; then
-        error "the following source path does not exist:"
-        error "$src"
+        error "the following source path does not exist: $src"
         return 1
     fi
 
@@ -168,26 +167,26 @@ create_symlink() {
     fi
 
     if test -L "$dst"; then
+        if test "$(readlink -f -- "$dst")" = "$src"; then
+            return 0
+        fi
+
         if $FORCE; then
-            if test "$(readlink -f "$dst")" != "$src"; then
-                remove_symlink "$2"
-            else
-                return 0
-            fi
+            remove_symlink "$rel_dst"
         elif $IGNORE_EXISTING; then
             return 0
         else
-            error "symbolic link already exists:"
-            error "$dst"
-            return 1
+            error "symlink exists but points elsewhere:" \
+                "$dst -> $(readlink -f -- "$dst")"
+            return 0
         fi
     elif test -e "$dst"; then
-        error "path already exists that is not a symlink:"
-        error "${dst}: $(stat -c '%F' -- "$dst")"
-        return 1
+        error "path already exists but is not a symlink:" \
+            "${dst}: $(stat -c '%F' -- "$dst")"
+        return 0
     fi
 
-    echo "Creating link: $dst -> $rel_src"
+    echo "Creating link: $dst -> $src"
     ln -s "$src" "$dst"
 }
 
@@ -206,14 +205,12 @@ copy_item() {
     rel_dst="$2"
 
     if test -z "$rel_src"; then
-        error "missing src argument:"
-        error "$0 $@"
+        error "missing src argument: $0 $@"
         return 1
     fi
 
     if test -z "$rel_dst"; then
-        error "missing dst argument:"
-        error "$0 $@"
+        error "missing dst argument: $0 $@"
         return 1
     fi
 
@@ -221,9 +218,8 @@ copy_item() {
     dst="${DEST_DIR}/$rel_dst"
     dst_parent="$(dirname -- "$dst")"
 
-    if ! test -e "$src"; then
-        error "the following source path does not exist:"
-        error "$src"
+    if ! test -f "$src"; then
+        error "source is not a regular file: $src"
         return 1
     fi
 
@@ -233,19 +229,26 @@ copy_item() {
     fi
 
     if test -e "$dst"; then
+        if cmp -s "$src" "$dst"; then
+            return 0
+        fi
+
+        if $DIFF; then
+            diff -u "$dst" "$src" || true
+        fi
+
         if $FORCE; then
             remove_path "$dst"
         elif $IGNORE_EXISTING; then
             return 0
         else
-            error "path already exists:"
-            error "${dst}"
-            return 1
+            error "file already exists and differs: ${dst}"
+            return 0
         fi
     fi
 
     echo "Copying item: from $rel_src to ${dst_parent}/"
-    cp -r "$src" "${dst_parent}/"
+    cp "$src" "${dst_parent}/"
 }
 
 create_all_symlinks() {
@@ -270,8 +273,7 @@ install_system_file() {
     rel="$1"
 
     if test -z "$rel"; then
-        error "missing path argument:"
-        error "$0 $@"
+        error "missing path argument: $0 $@"
         return 1
     fi
 
@@ -280,8 +282,7 @@ install_system_file() {
     dst_parent="$(dirname -- "$dst")"
 
     if ! test -e "$src"; then
-        error "the following source path does not exist:"
-        error "$src"
+        error "the following source path does not exist: $src"
         return 1
     fi
 
@@ -295,14 +296,17 @@ install_system_file() {
             return 0
         fi
 
+        if $DIFF; then
+            sudo diff -u "$dst" "$src" || true
+        fi
+
         if $FORCE; then
             echo "Overwriting: $dst"
         elif $IGNORE_EXISTING; then
             return 0
         else
-            error "system file already exists and differs (use --force to overwrite):"
-            error "$dst"
-            return 1
+            error "system file already exists and differs: $dst"
+            return 0
         fi
     fi
 
@@ -319,7 +323,7 @@ install_all_system_files() {
 check_terminfo() {
     if ! infocmp tmux-256color > /dev/null; then
         error "Missing terminfo for tmux-256color. Try installing ncurses-term."
-        return 1
+        return 0
     fi
 }
 
@@ -332,6 +336,7 @@ print_help() {
     echo "    -f, --force               Overwrite any existing links"
     echo "    -i, --ignore-existing     Ignore existing symlinks"
     echo "    -r, --remove-existing     Remove any existing symlinks"
+    echo "    -d, --diff                Show unified diff when a managed file differs"
 }
 
 while [ $# -gt 0 ]; do
@@ -352,6 +357,10 @@ while [ $# -gt 0 ]; do
             IGNORE_EXISTING=true
             shift
             ;;
+        -d|--diff)
+            DIFF=true
+            shift
+            ;;
         *)
             error "unknown option: $1"
             PRINT_HELP=true