updated README.txt

README.txt

@@ -17,6 +17,7 @@ REQUIREMENTS
 - Optional: wl-copy / xclip / xsel / pbcopy  (for clipboard support)
 - Optional: mpv, vlc, feh, zathura, etc.     (for smart file opening)
 - Optional: readlink                         (for symlink display)
+- Optional: file                             (for MIME type detection)
 
 
 INSTALLATION
@@ -41,9 +42,15 @@ Manual installation:
 
 USAGE
 -----
-   sfm
+   sfm [path]
 
-sfm will opens in the current directory.
+If no path is given, sfm opens in the current directory.
+
+Examples:
+   sfm              # open in current directory
+   sfm /mnt/data    # open at a specific path
+   sfm ~            # open home directory
+   sfm ..           # open parent directory
 
 
 NAVIGATION
@@ -68,11 +75,23 @@ DISPLAY TOGGLES
 ---------------
   .       Toggle hidden files (dotfiles)
   T       Toggle size/date detail column
+  P       Toggle preview pane (right side)
   s       Cycle sort mode: name -> size -> date
   i       Show file info (permissions, size, date) in status bar
   R       Refresh current directory listing
 
 
+PREVIEW PANE
+------------
+Press P to toggle the preview pane on the right side of the screen.
+The list pane takes the left half, preview takes the right half.
+
+  Text files      Shows file contents line by line
+  Directories     Shows entry count
+  Symlinks        Shows link target
+  Binary files    Shows file size
+
+
 FILE OPERATIONS
 ---------------
   r       Rename selected entry
@@ -164,4 +183,3 @@ DATA FILES
 ----------
   ~/.config/sfm/bookmarks     Saved bookmarks (one path per line)
   ~/.local/share/sfm-trash/   Trashed files
-

sfm

@@ -61,7 +61,11 @@ term_rows()   { tput_cmd lines || echo 24; }
 term_cols()   { tput_cmd cols  || echo 80; }
 
 # --- state ---
-CWD="$PWD"
+if [ -n "$1" ]; then
+    CWD=$(cd "$1" 2>/dev/null && pwd) || { printf 'sfm: %s: no such directory\n' "$1" >&2; exit 1; }
+else
+    CWD=$(cd "$PWD" 2>/dev/null && pwd) || CWD="/"
+fi
 SEL=0
 OFFSET=0
 PREV_SEL=0
@@ -79,9 +83,20 @@ INFO_MSG=""     # ephemeral message shown in botbar
 SHOW_HIDDEN=0   # 1 = show dotfiles
 SORT_MODE="name" # name | size | date
 SHOW_DETAILS=0   # 1 = show size+date column
+SHOW_PREVIEW=0   # 1 = show preview pane on right
 TRASH_DIR="${XDG_DATA_HOME:-$HOME/.local/share}/sfm-trash"
 mkdir -p "$TRASH_DIR"
 PREV_CWD=""     # last visited directory, for jumping back
+
+# normalise CWD: resolve to absolute canonical path, no double slashes
+norm_cwd() {
+    CWD=$(cd "$CWD" 2>/dev/null && pwd) || CWD="/"
+    # squeeze any double slashes (some systems return // for //<path>)
+    CWD=$(printf '%s' "$CWD" | tr -s '/')
+}
+
+# safely join CWD with a name, avoiding double slash at root
+joinpath() { [ "$CWD" = "/" ] && printf '/%s' "$1" || printf '%s/%s' "$CWD" "$1"; }
 BOOKMARK_FILE="${XDG_CONFIG_HOME:-$HOME/.config}/sfm/bookmarks"
 mkdir -p "$(dirname "$BOOKMARK_FILE")"
 [ -f "$BOOKMARK_FILE" ] || touch "$BOOKMARK_FILE"
@@ -94,17 +109,19 @@ load_entries() {
     # build list of dir names then file names, including dotfiles if enabled
     for d in "$CWD"/*/; do
         [ -d "$d" ] || continue
+        [ -L "${d%/}" ] && continue   # symlinks handled separately
         name="${d%/}"; name="${name##*/}"
         [ "$name" = "*" ] && continue
-        case "$name" in .*) continue ;; esac   # skip dotdirs here, handle below
+        case "$name" in .*) continue ;; esac
         ENTRIES="$ENTRIES
 ${name}/"
         COUNT=$((COUNT + 1))
     done
     if [ "$SHOW_HIDDEN" = "1" ]; then
-        for d in "$CWD"/./; do : ; done        # no-op, just to avoid error
+        for d in "$CWD"/./; do : ; done
         for d in "$CWD"/.*/; do
             [ -d "$d" ] || continue
+            [ -L "${d%/}" ] && continue   # symlinks handled separately
             name="${d%/}"; name="${name##*/}"
             [ "$name" = "." ] || [ "$name" = ".." ] && continue
             [ "$name" = ".*" ] && continue
@@ -416,6 +433,85 @@ render_row() {
     fi
 }
 
+draw_preview() {
+    _rows=$1; _cols=$2; _px=$3; _pw=$4
+    entry=$(get_entry "$SEL")
+    # clear preview area first
+    _r=2
+    while [ "$_r" -le $((_rows - 1)) ]; do
+        goto "$_r" "$_px"
+        printf '\033[K'
+        _r=$((_r + 1))
+    done
+    [ -z "$entry" ] && return
+    _path=$(joinpath "${entry%/}"); _path="${_path%@}"
+
+    # draw vertical divider
+    _r=2
+    while [ "$_r" -le $((_rows - 1)) ]; do
+        goto "$_r" $((_px - 1))
+        printf '%s|%s' "${CYAN}" "${RESET}"
+        _r=$((_r + 1))
+    done
+
+    case "$entry" in
+        */)
+            # directory: show entry count
+            _dc=$(ls -1 "$_path" 2>/dev/null | wc -l | tr -d '[:space:]')
+            goto 2 "$_px"
+            printf '%s[dir] %s items%s' "${CYAN}" "${_dc}" "${RESET}"
+            ;;
+        *@)
+            # symlink
+            _tgt=$(readlink "$_path" 2>/dev/null || echo "?")
+            goto 2 "$_px"
+            printf '%s[symlink]%s' "${MAGENTA}${BOLD}" "${RESET}"
+            goto 3 "$_px"
+            printf '%s-> %s%s' "${WHITE}" "${_tgt}" "${RESET}"
+            ;;
+        *)
+            # detect if text via extension or mime
+            _ext="${entry##*.}"
+            _ext=$(printf '%s' "$_ext" | tr '[:upper:]' '[:lower:]')
+            _is_text=0
+            case "$_ext" in
+                txt|md|markdown|rst|log|conf|cfg|ini|toml|yaml|yml|\
+                sh|bash|zsh|py|rb|pl|lua|js|ts|json|xml|html|htm|\
+                css|c|h|cpp|rs|go|java|php|r|sql|vim|env|gitignore|\
+                diff|patch|csv|tsv|lock|mod|sum) _is_text=1 ;;
+            esac
+            if [ "$_is_text" = "0" ] && command -v file >/dev/null 2>&1; then
+                case "$(file --mime-type -b "$_path" 2>/dev/null)" in
+                    text/*) _is_text=1 ;;
+                esac
+            fi
+            if [ "$_is_text" = "1" ]; then
+                _max_lines=$((_rows - 3))
+                _line_n=0
+                while IFS= read -r _line && [ "$_line_n" -lt "$_max_lines" ]; do
+                    # truncate to preview width
+                    if [ "${#_line}" -gt "$((_pw - 1))" ]; then
+                        _line=$(printf '%s' "$_line" | cut -c1-$((_pw - 2)))
+                        _line="${_line}~"
+                    fi
+                    goto "$((_line_n + 2))" "$_px"
+                    printf '%s%s%s' "${WHITE}" "$_line" "${RESET}"
+                    _line_n=$((_line_n + 1))
+                done < "$_path"
+                if [ "$_line_n" -eq 0 ]; then
+                    goto 2 "$_px"
+                    printf '%s(empty file)%s' "${WHITE}" "${RESET}"
+                fi
+            else
+                # binary / unknown
+                goto 2 "$_px"
+                _sz=$(ls -lh "$_path" 2>/dev/null | awk '{print $5}')
+                printf '%s[binary] %s%s' "${YELLOW}" "${_sz}" "${RESET}"
+            fi
+            ;;
+    esac
+}
+
 draw_topbar() {
     _cols=$1
     spaces=$(printf '%*s' "$_cols" '')
@@ -426,7 +522,7 @@ draw_topbar() {
 draw_botbar() {
     _rows=$1; _cols=$2
     if [ "$SEARCHING" = "1" ]; then
-        info=" $((SEL + 1))/${COUNT} ${CWD}"
+        info=" $([ "$COUNT" -eq 0 ] && echo 0 || echo $((SEL + 1)))/${COUNT} ${CWD}"
         keys=" search: ${FILTER} "
         maxk=$((_cols - ${#info} - 1))
         [ "${#keys}" -gt "$maxk" ] && keys=$(printf '%s' "$keys" | cut -c1-"$maxk")
@@ -440,9 +536,8 @@ draw_botbar() {
             "${YELLOW}${keys}" \
             "${RESET}"
     elif [ -n "$INFO_MSG" ]; then
-        info=" $((SEL + 1))/${COUNT} ${CWD}"
+        info=" $([ "$COUNT" -eq 0 ] && echo 0 || echo $((SEL + 1)))/${COUNT} ${CWD}"
-        msg=" ${INFO_MSG} "
+        msg=" ${INFO_MSG} "        padlen=$((_cols - ${#info} - ${#msg}))
-        padlen=$((_cols - ${#info} - ${#msg}))
         [ "$padlen" -lt 0 ] && padlen=0
         pad=$(printf '%*s' "$padlen" '')
         goto "$_rows" 1
@@ -461,7 +556,7 @@ draw_botbar() {
         [ "$SORT_MODE" != "name" ] && _ind="${_ind} [sort:${SORT_MODE}]"
         [ "$SHOW_DETAILS" = "1" ]  && _ind="${_ind} [details]"
         hint="  press ? for help "
-        info=" $((SEL + 1))/${COUNT} ${CWD}${_ind}"
+        info=" $([ "$COUNT" -eq 0 ] && echo 0 || echo $((SEL + 1)))/${COUNT} ${CWD}${_ind}"
         padlen=$((_cols - ${#info} - ${#hint}))
         [ "$padlen" -lt 0 ] && padlen=0
         pad=$(printf '%*s' "$padlen" '')
@@ -479,6 +574,15 @@ draw() {
     COLS=$(term_cols)
     LIST_ROWS=$((ROWS - 2))   # row 1 = topbar, row ROWS = botbar
 
+    # split layout when preview enabled
+    if [ "$SHOW_PREVIEW" = "1" ]; then
+        LIST_COLS=$((COLS / 2))
+        PREV_COL=$((LIST_COLS + 2))
+        PREV_WIDTH=$((COLS - LIST_COLS - 2))
+    else
+        LIST_COLS=$COLS
+    fi
+
     # clamp selection
     [ "$SEL" -lt 0 ] && SEL=0
     [ "$COUNT" -gt 0 ] && [ "$SEL" -ge "$COUNT" ] && SEL=$((COUNT - 1))
@@ -494,7 +598,6 @@ draw() {
     [ "$OFFSET" != "$PREV_OFFSET" ] && NEED_FULL_REDRAW=1
 
     if [ "$NEED_FULL_REDRAW" = "1" ]; then
-        # --- full repaint: move to top without erasing, overwrite every row ---
         printf '\033[H'
         draw_topbar "$COLS"
 
@@ -502,22 +605,29 @@ draw() {
         idx=$OFFSET
         while [ "$row" -le $((LIST_ROWS + 1)) ] && [ "$idx" -lt "$COUNT" ]; do
             sel=0; [ "$idx" -eq "$SEL" ] && sel=1
-            render_row "$row" "$idx" "$sel" "$COLS"
+            render_row "$row" "$idx" "$sel" "$LIST_COLS"
             row=$((row + 1))
             idx=$((idx + 1))
         done
-        # blank leftover rows (e.g. after entering a smaller directory)
+        # show (empty) if directory has no entries
+        if [ "$COUNT" -eq 0 ]; then
+            goto 2 1
+            printf '%s  (empty)%s%s' "${WHITE}" "${ERASE_LINE}" "${RESET}"
+            row=3
+        fi
+        # blank leftover rows
         while [ "$row" -le $((LIST_ROWS + 1)) ]; do
             goto "$row" 1
             printf '%s' "${ERASE_LINE}"
             row=$((row + 1))
         done
 
+        [ "$SHOW_PREVIEW" = "1" ] && draw_preview "$ROWS" "$COLS" "$PREV_COL" "$PREV_WIDTH"
+
         draw_botbar "$ROWS" "$COLS"
         NEED_FULL_REDRAW=0
     else
-        # --- fast path: only touch the two rows whose highlight state changed ---
+        # --- fast path ---
-        # if nothing moved, skip entirely — no flicker at boundaries
         if [ "$SEL" = "$PREV_SEL" ] && [ "$OFFSET" = "$PREV_OFFSET" ]; then
             return 2>/dev/null || true
         fi
@@ -525,12 +635,14 @@ draw() {
         new_row=$(( (SEL      - OFFSET) + 2 ))
 
         if [ "$prev_row" -ge 2 ] && [ "$prev_row" -le $((LIST_ROWS + 1)) ]; then
-            render_row "$prev_row" "$PREV_SEL" 0 "$COLS"
+            render_row "$prev_row" "$PREV_SEL" 0 "$LIST_COLS"
         fi
         if [ "$new_row" -ge 2 ] && [ "$new_row" -le $((LIST_ROWS + 1)) ]; then
-            render_row "$new_row" "$SEL" 1 "$COLS"
+            render_row "$new_row" "$SEL" 1 "$LIST_COLS"
         fi
 
+        [ "$SHOW_PREVIEW" = "1" ] && draw_preview "$ROWS" "$COLS" "$PREV_COL" "$PREV_WIDTH"
+
         draw_botbar "$ROWS" "$COLS"
     fi
 
@@ -744,7 +856,7 @@ do_help() {
     bw=$((COLS - 4))
     [ "$bw" -gt 52 ] && bw=52
     [ "$bw" -lt 36 ] && bw=36
-    bh=41
+    bh=42
     _help_bx=$(( (COLS - bw) / 2 )); [ "$_help_bx" -lt 1 ] && _help_bx=1
     _help_by=$(( (ROWS - bh) / 2 )); [ "$_help_by" -lt 1 ] && _help_by=1
     _help_iw=$((bw - 2))
@@ -766,32 +878,33 @@ do_help() {
     help_row 11 "  i     file info in status bar"
     help_row 12 "  s     cycle sort: name/size/date"
     help_row 13 "  T     toggle size/date details"
-    help_sep 14
+    help_row 14 "  P     toggle preview pane"
-    help_row 15 "  space  toggle multi-select"
+    help_sep 15
-    help_row 16 "  a      select all / deselect all"
+    help_row 16 "  space  toggle multi-select"
-    help_row 17 "  y      yank/copy  (works on selection)"
+    help_row 17 "  a      select all / deselect all"
-    help_row 18 "  x      cut        (works on selection)"
+    help_row 18 "  y      yank/copy  (works on selection)"
-    help_row 19 "  p      paste"
+    help_row 19 "  x      cut        (works on selection)"
-    help_row 20 "  d      delete     (works on selection)"
+    help_row 20 "  p      paste"
-    help_sep 21
+    help_row 21 "  d      delete     (works on selection)"
-    help_row 22 "  r   rename         R   refresh"
+    help_sep 22
-    help_row 23 "  m   make directory"
+    help_row 23 "  r   rename         R   refresh"
-    help_row 24 "  n   new file"
+    help_row 24 "  m   make directory"
-    help_row 25 "  u   trash file (safe delete)"
+    help_row 25 "  n   new file"
-    help_row 26 "  U   open trash directory"
+    help_row 26 "  u   trash file (safe delete)"
-    help_row 27 "  !   drop to shell in CWD"
+    help_row 27 "  U   open trash directory"
-    help_row 28 "  o   open with custom program"
+    help_row 28 "  !   drop to shell in CWD"
-    help_sep 29
+    help_row 29 "  o   open with custom program"
-    help_row 30 "  b   bookmark current dir"
+    help_sep 30
-    help_row 31 "  B   open bookmark picker"
+    help_row 31 "  b   bookmark current dir"
-    help_row 32 "  c   copy path to clipboard"
+    help_row 32 "  B   open bookmark picker"
-    help_row 33 "  ~   go to home directory"
+    help_row 33 "  c   copy path to clipboard"
-    help_row 34 "  \`   jump to previous directory"
+    help_row 34 "  ~   go to home directory"
-    help_sep 35
+    help_row 35 "  \`   jump to previous directory"
-    help_row 36 "  q   quit"
+    help_sep 36
-    help_row 37 "  ?   this help"
+    help_row 37 "  q   quit"
-    help_row 38 ""
+    help_row 38 "  ?   this help"
-    help_row 39 "  press any key to close..."
+    help_row 39 ""
+    help_row 40 "  press any key to close..."
 
     goto "$(( _help_by + bh ))" "$_help_bx"
     printf '%s+%s+%s' "${BOLD}${CYAN}" "$_help_hl" "${RESET}"
@@ -856,11 +969,18 @@ do_toggle_hidden() {
 
 do_toggle_details() {
     if [ "$SHOW_DETAILS" = "0" ]; then
-        SHOW_DETAILS=1
+        SHOW_DETAILS=1; INFO_MSG="details on"
-        INFO_MSG="details on"
     else
-        SHOW_DETAILS=0
+        SHOW_DETAILS=0; INFO_MSG="details off"
-        INFO_MSG="details off"
+    fi
+    NEED_FULL_REDRAW=1
+}
+
+do_toggle_preview() {
+    if [ "$SHOW_PREVIEW" = "0" ]; then
+        SHOW_PREVIEW=1; INFO_MSG="preview on"
+    else
+        SHOW_PREVIEW=0; INFO_MSG="preview off"
     fi
     NEED_FULL_REDRAW=1
 }
@@ -871,7 +991,7 @@ do_go_back() {
     SELECTED=""
     PREV_CWD="$CWD"
     LAST_CHILD="${CWD##*/}/"   # name of current dir with trailing slash
-    CWD=$(dirname "$CWD")
+    CWD=$(cd "$(dirname "$CWD")" && pwd)
     SEL=0; OFFSET=0; PREV_SEL=0; PREV_OFFSET=0
     load_entries
     # restore selection to the directory we just came from
@@ -888,20 +1008,20 @@ do_open() {
         */)
             FILTER=""
             SELECTED=""
-            _target="${CWD}/${entry%/}"
+            _target=$(joinpath "${entry%/}")
             if [ ! -x "$_target" ] || [ ! -r "$_target" ]; then
                 INFO_MSG="permission denied: ${entry%/}"
                 NEED_FULL_REDRAW=1
                 return
             fi
             PREV_CWD="$CWD"
-            CWD=$(cd "$_target" && pwd)
+            CWD=$(cd "$_target" && pwd); norm_cwd
             SEL=0; OFFSET=0; PREV_SEL=0; PREV_OFFSET=0
             load_entries
             ;;
         *@)
             _name="${entry%@}"
-            _target="${CWD}/${_name}"
+            _target=$(joinpath "$_name")
             if [ -d "$_target" ]; then
                 if [ ! -x "$_target" ] || [ ! -r "$_target" ]; then
                     INFO_MSG="permission denied: ${_name}"
@@ -910,7 +1030,7 @@ do_open() {
                 fi
                 FILTER=""; SELECTED=""
                 PREV_CWD="$CWD"
-                CWD=$(cd "$_target" && pwd)
+                CWD=$(cd "$_target" && pwd); norm_cwd
                 SEL=0; OFFSET=0; PREV_SEL=0; PREV_OFFSET=0
                 load_entries
             else
@@ -1057,7 +1177,7 @@ do_shell() {
     printf '%s(type "exit" to return to fm)%s\n' "${YELLOW}" "${RESET}"
     ${SHELL:-sh}
     # restore CWD in case user cd'd around
-    CWD="${PWD}"
+    CWD="${PWD}"; norm_cwd
     setup_term; hide_cursor
     NEED_FULL_REDRAW=1
 }
@@ -1093,7 +1213,7 @@ do_trash() {
 do_open_trash() {
     PREV_CWD="$CWD"
     FILTER=""; SELECTED=""
-    CWD="$TRASH_DIR"
+    CWD="$TRASH_DIR"; norm_cwd
     SEL=0; OFFSET=0; PREV_SEL=0; PREV_OFFSET=0
     load_entries
 }
@@ -1122,7 +1242,7 @@ do_copy_path() {
 do_jump_back() {
     [ -z "$PREV_CWD" ] && { INFO_MSG="no previous directory"; NEED_FULL_REDRAW=1; return; }
     _tmp="$CWD"
-    CWD="$PREV_CWD"
+    CWD="$PREV_CWD"; norm_cwd
     PREV_CWD="$_tmp"
     FILTER=""; SELECTED=""
     SEL=0; OFFSET=0; PREV_SEL=0; PREV_OFFSET=0
@@ -1197,7 +1317,7 @@ do_bookmark_jump() {
                     '[C') # right — open
                         _chosen=$(awk -v n="$_bsel" 'NR==n&&NF{print;exit}' "$BOOKMARK_FILE")
                         if [ -n "$_chosen" ] && [ -d "$_chosen" ]; then
-                            PREV_CWD="$CWD"; CWD="$_chosen"
+                            PREV_CWD="$CWD"; CWD="$_chosen"; norm_cwd
                             FILTER=""; SELECTED=""
                             SEL=0; OFFSET=0; PREV_SEL=0; PREV_OFFSET=0
                             load_entries
@@ -1213,7 +1333,7 @@ do_bookmark_jump() {
             l)
                 _chosen=$(awk -v n="$_bsel" 'NR==n&&NF{print;exit}' "$BOOKMARK_FILE")
                 if [ -n "$_chosen" ] && [ -d "$_chosen" ]; then
-                    PREV_CWD="$CWD"; CWD="$_chosen"
+                    PREV_CWD="$CWD"; CWD="$_chosen"; norm_cwd
                     FILTER=""; SELECTED=""
                     SEL=0; OFFSET=0; PREV_SEL=0; PREV_OFFSET=0
                     load_entries
@@ -1364,6 +1484,7 @@ while true; do
         /)   do_search        ;;
         '.')  do_toggle_hidden   ;;
         T)    do_toggle_details  ;;
+        P)    do_toggle_preview  ;;
         i)   do_info          ;;
         '!') do_shell         ;;
         o)   do_open_with     ;;
@@ -1371,7 +1492,7 @@ while true; do
         u)   do_trash        ;;
         U)   do_open_trash   ;;
         '`') do_jump_back    ;;
-        '~') PREV_CWD="$CWD"; CWD="$HOME"; FILTER=""; SELECTED=""
+        '~') PREV_CWD="$CWD"; CWD=$(cd "$HOME" && pwd); FILTER=""; SELECTED=""
              SEL=0; OFFSET=0; PREV_SEL=0; PREV_OFFSET=0; load_entries ;;
         c)   do_copy_path   ;;
         "$(printf '\033')") do_clear_filter ;;