Runtime check of dependencies, added selfupdate from github repo, and…

… help.

ipfs-wormhole.sh

@@ -13,27 +13,82 @@ IFS=$'\n\t'
 # - gpg
 # - ipfs
 
+# Check deps
+
+set +e
+PWGENCMD="$(command -v pwgen)"
+GPGCMD="$(command -v gpg)"
+IPFSCMD="$(command -v ipfs)"
+set +e
+
+ERROR=0
+if [ -z "$PWGENCMD" ]; then
+  echo pwgen not found
+  ERROR=1
+fi
+if [ -z "$GPGCMD" ]; then
+  echo gpg not found
+  ERROR=1
+fi
+if [ -z "$IPFSCMD" ]; then
+  echo ipfs not found
+  ERROR=1
+fi
+
+[ "$ERROR" -eq 1 ] && exit 1
+
 case "${1:-}" in
 send)
   echo "Send..."
-  PASSWORD=$(pwgen -1 20)
+  PASSWORD=$($PWGENCMD -1 20)
   FILE=${2:-}
-  TAG=$(gpg --batch --passphrase="$PASSWORD" -c -o - "$FILE" |
-    ipfs add -Q)
+  TAG=$($GPGCMD --batch --passphrase="$PASSWORD" -c -o - "$FILE" |
+    $IPFSCMD add -Q)
   FILENAME="$(echo "$FILE" | base64)"
-  echo "Retrieve with $0 receive $TAG$PASSWORD$FILENAME"
+  RECEIVECMD="$0 receive $TAG$PASSWORD$FILENAME"
+  echo "Retrieve with $RECEIVECMD"
+  set +e
+  XCLIPCMD="$(command -v xclipe)"
+  set -e
+  if [ -n "$XCLIPCMD" ]; then
+    echo "$RECEIVECMD" | $XCLIPCMD
+    echo "Copied to clipboard"
+  fi
   exit 0
   ;;
 receive)
   DSTFILENAME="$(echo "${2:66}" | base64 -d)"
   echo "Receiving $DSTFILENAME..."
-  ipfs cat "${2:0:46}" |
-    gpg --batch --passphrase="${2:46:20}" -d \
+  $IPFSCMD cat "${2:0:46}" |
+    $GPGCMD --batch --passphrase="${2:46:20}" -d \
       >"$DSTFILENAME" \
       2>/dev/null
   exit 0
   ;;
-esac
+update)
+  echo Update...
+  wget -O "${0:-}" \
+    https://raw.githubusercontent.com/aurelg/ipfs-wormhole/master/ipfs-wormhole.sh
+  exit 0
+  ;;
+*)
+  cat <<EOM
+Get things from one computer to another, safely. Over IPFS.
 
-echo "${0:-} send <filename>"
-echo "${0:-} receive <tag>"
+On machine A:
+-------------
+
+${0:-} send <filename>
+
+# Will encrypt and add the file to IPFS, and output a tag (and copy it to the
+# clipboard if xclip is installed)
+
+On machine B:
+-------------
+
+${0:-} receive <tag>
+
+# Will retrieve the file over IPFS, decrypt it and save it locally.
+EOM
+  ;;
+esac