Scripts: Add dist/export-help.sh

Signed-off-by: Michael Mayer <michael@photoprism.app>

scripts/dist/export-help.sh

@@ -0,0 +1,73 @@
+#!/usr/bin/env bash
+
+# Recursively dumps CLI usage information into [command]-cli-commands.txt"
+# Usage: ./export-help.sh [command]
+
+set -u -o pipefail
+
+if [[ $# -lt 1 ]]; then
+  echo "Usage: $0 <command>" >&2
+  exit 1
+fi
+
+ROOT_CMD="$1"
+OUTFILE="$(basename "$ROOT_CMD")-cli-commands.txt"
+
+# Start with a clean file
+: > "$OUTFILE"
+
+# Bash ≥ 4 required for associative arrays.
+declare -A VISITED
+FIRST_BLOCK=1
+
+crawl() {
+  local full_cmd=("$@")
+  local key="${full_cmd[*]}"
+
+  # Skip if already processed (handles aliases)
+  if [[ -n "${VISITED[$key]+x}" ]]; then
+    return
+  fi
+  VISITED["$key"]=1
+
+  # Capture --help (stdout+stderr)
+  local out
+  if ! out="$("${full_cmd[@]}" --help 2>&1)"; then
+    : # continue even if non-zero exit
+  fi
+
+  # Append block
+  if (( FIRST_BLOCK )); then
+    FIRST_BLOCK=0
+    printf "%s\n" "$out" >> "$OUTFILE"
+  else
+    printf "\n---\n\n%s\n" "$out" >> "$OUTFILE"
+  fi
+
+  # Extract subcommand names from COMMANDS: (or "Available Commands:") section(s)
+  mapfile -t subs < <(printf "%s\n" "$out" | awk '
+    BEGIN { section=0 }
+    /^[[:space:]]*(COMMANDS|Available Commands):/ { section=1; next }
+    section==1 && /^[A-Z][A-Z ]*:/ { section=0; next }  # next ALL-CAPS header ends the section
+    section==1 {
+      # Lines look like: "start, up        Starts the Web server"
+      s=$0
+      sub(/^[[:space:]]+/,"",s)
+      if (s ~ /^[[:alnum:]][[:alnum:]-]*/) {
+        # First token up to comma/space; skip help aliases
+        split(s, a, /[,[:space:]]+/)
+        if (a[1] != "" && a[1] != "help" && a[1] != "h") print a[1]
+      }
+    }
+  ' | sort -u)
+
+  # Recurse into each subcommand
+  local sub
+  for sub in "${subs[@]}"; do
+    crawl "${full_cmd[@]}" "$sub"
+  done
+}
+
+crawl "$ROOT_CMD"
+
+echo "Wrote command help to: $OUTFILE"