Make zsh widget smarter (denisidoro#479)

Related: denisidoro#463, from @enisozgen 

Before releasing a new version, this will be refactored

shell/navi.plugin.zsh

@@ -1,19 +1,147 @@
 #!/usr/bin/env zsh
 
+# Copy-pasted from https://gist.github.com/enisozgen/2109cc80ea9f405f80c6c383f2375e77
+
+
+# Change last part of the command
+# NOTE Creates sometime problem if there is same word in the input
+ChangeLastCommand()
+{
+    [[ -z  "${2// }" ]] && printf "%s" "$(echo "${1}${3}")" || printf "%s" "$(echo "${1/$2/ $3}")"
+}
+
+SendLastCommandAfterPIPE()
+{
+    # Send last command after pipe
+    INPUT_STRING="${1}"
+    a=("${(@s/|/)${INPUT_STRING}}") # | modifier
+    printf "%s" "$(echo "${a[-1]}")"
+}
+
+
+# Is there pipe in the input string
+IsPipeExist()
+{
+    INPUT_STRING=$1
+    if [[ $INPUT_STRING == *\|* ]]; then
+        NAVI_PIPE="true"
+    else
+        NAVI_PIPE="false"
+    fi
+}
+
+
+IsOnlySpace ()
+{
+    if [[ -z  "${1// }" ]] ; then
+        return 0
+    else
+        return 1
+    fi
+}
+
+NaviUISearch()
+{
+    NAVI_RET=$(printf "%s" "$(navi --print --fzf-overrides '--no-select-1' --query "${1}" </dev/tty)")
+    printf ${NAVI_RET}
+}
+
+
+NaviOutputControl ()
+{
+    if ! [[ -z "$1" ]] ; then
+        return 0
+    else
+        return 1
+    fi
+}
+
+
+
+SmartNavi()
+{
+    if  IsOnlySpace $1 ; then
+        NAVI_RET=$(printf "%s" "$(navi --print  --fzf-overrides '--no-select-1' </dev/tty)")
+    else
+        NAVI_RET=$(printf "%s" "$(navi --print --best-match --fzf-overrides '--no-select-1' --query "${1}" </dev/tty)")
+    fi
+
+
+    # Return warning if there is no output else return best match
+    if NaviOutputControl ${NAVI_RET}; then
+        printf ${NAVI_RET}
+    else
+        printf "Navi Returned Empty"
+    fi
+}
+
+
 _call_navi() {
-  local selected
-  if [ -n "$LBUFFER" ]; then
-    if selected="$(printf "%s" "$(navi --print --fzf-overrides '--no-select-1' --query "${LBUFFER}" </dev/tty)")"; then
-      LBUFFER="$selected"
+    local selected
+    if [ -n "$LBUFFER" ]; then
+        if selected="$(printf "%s" "$(navi --print --fzf-overrides '--no-select-1' --query "${LBUFFER}" </dev/tty)")"; then
+            LBUFFER="$selected"
+        fi
+    else
+        # If there is not any word on list
+        if selected="$(printf "%s" "$(navi --print </dev/tty)")"; then
+            LBUFFER="$selected"
+        fi
     fi
-  else
-    if selected="$(printf "%s" "$(navi --print </dev/tty)")"; then
-      LBUFFER="$selected"
+    region_highlight=("P0 100 bold")
+    zle redisplay
+}
+
+_call_smart_navi() {
+
+    # set -x
+    INPUT_STRING=$LBUFFER
+    IsPipeExist ${INPUT_STRING}
+
+
+    # Is there some written stuff in LBUFFER ?
+    if ! [ -z "$INPUT_STRING" ] ; then
+        # If last navi output same as current input
+        # Use this part when you don't like navi best match
+        if [ "${LASTWIDGET}"  = "_call_smart_navi" ]  && [ "${OUTPUT_STRING}"  = "$INPUT_STRING" ];then
+            LBUFFER_LAST_COMMAND=$(SendLastCommandAfterPIPE "${INPUT_STRING}")
+
+            # Searching with same input as before but this time we are using navi interactive UI since navi didn't return us what we want
+            OUTPUT_STRING=$(NaviUISearch  ${PREVIOUS_LAST})
+            OUTPUT_STRING=$(ChangeLastCommand "$INPUT_STRING" "$LBUFFER_LAST_COMMAND" "$OUTPUT_STRING")
+
+        else
+            # First search always start from here!!!
+            if [ "${NAVI_PIPE}" = "false" ] ; then
+
+                # LBUFFER_LAST_COMMAND=$(SendLastCommandAfterPIPE "${INPUT_STRING}")
+                # PREVIOUS_LAST=$LBUFFER_LAST_COMMAND
+
+                # Remember what was last command after pipe
+                PREVIOUS_LAST=$INPUT_STRING
+                OUTPUT_STRING=$(SmartNavi ${INPUT_STRING})
+
+            else
+                LBUFFER_LAST_COMMAND=$(SendLastCommandAfterPIPE "${INPUT_STRING}")
+
+                # Remember what was last command after pipe
+                PREVIOUS_LAST=$LBUFFER_LAST_COMMAND
+
+                OUTPUT_STRING=$(SmartNavi ${LBUFFER_LAST_COMMAND})
+                OUTPUT_STRING=$(ChangeLastCommand "$INPUT_STRING" "$LBUFFER_LAST_COMMAND" "$OUTPUT_STRING")
+
+            fi
+        fi
+        LBUFFER="$OUTPUT_STRING"
+    else
+        # There is nothing use default navi command
+        _call_navi
     fi
-  fi
-  zle redisplay
+
+    region_highlight=("P0 100 bold")
+    zle redisplay
 }
 
-zle -N _call_navi
 
-bindkey '^g' _call_navi
+zle -N _call_smart_navi
+bindkey '^g' _call_smart_navi