Add prompt.ksh

prompt.ksh

@@ -0,0 +1,308 @@
+# ============================================================
+# Custom OpenBSD ksh prompt
+# ============================================================
+
+
+# ------------------------------------------------------------
+# Colors
+# ------------------------------------------------------------
+
+RESET="$(printf '\033[0m')"
+
+RED="$(printf '\033[31m')"
+GREEN="$(printf '\033[32m')"
+YELLOW="$(printf '\033[33m')"
+BLUE="$(printf '\033[34m')"
+MAGENTA="$(printf '\033[35m')"
+CYAN="$(printf '\033[36m')"
+WHITE="$(printf '\033[37m')"
+
+# 256-color dark gray
+DARK_GRAY="$(printf '\033[38;5;238m')"
+
+BOLD_RED="$(printf '\033[1;31m')"
+BOLD_GREEN="$(printf '\033[1;32m')"
+BOLD_YELLOW="$(printf '\033[1;33m')"
+BOLD_BLUE="$(printf '\033[1;34m')"
+BOLD_CYAN="$(printf '\033[1;36m')"
+
+
+# ------------------------------------------------------------
+# User / root
+# ------------------------------------------------------------
+
+PROMPT_USER="${USER:-$(id -un)}"
+
+if [ "$(id -u)" -eq 0 ]; then
+    USER_COLOR="$BOLD_RED"
+    PROMPT_CHAR="#"
+else
+    USER_COLOR="$BOLD_GREEN"
+    PROMPT_CHAR="$"
+fi
+
+
+# ------------------------------------------------------------
+# Hostname
+# ------------------------------------------------------------
+
+PROMPT_HOST="$(hostname)"
+PROMPT_HOST="${PROMPT_HOST%%.*}"
+
+
+# ------------------------------------------------------------
+# Git
+#
+# Examples:
+#
+#   git:main ✓
+#   git:feature/auth +2 ~3 ?1
+#   git:main ↑2 ↓1
+#
+#   + = staged
+#   ~ = modified
+#   ? = untracked
+#   ↑ = commits ahead of upstream
+#   ↓ = commits behind upstream
+# ------------------------------------------------------------
+
+git_prompt()
+{
+    typeset branch
+    typeset counts
+    typeset staged modified untracked
+    typeset upstream
+    typeset ahead behind
+
+    # Git must exist.
+    whence git >/dev/null 2>&1 || return
+
+    # We must be inside a Git repository.
+    git rev-parse --is-inside-work-tree >/dev/null 2>&1 || return
+
+    # Current branch.
+    branch="$(git symbolic-ref --quiet --short HEAD 2>/dev/null)"
+
+    # Detached HEAD.
+    if [ -z "$branch" ]; then
+        branch="@$(git rev-parse --short HEAD 2>/dev/null)"
+    fi
+
+    # Count staged, modified and untracked files.
+    counts="$(
+        git status --porcelain 2>/dev/null |
+        awk '
+        {
+            index_status = substr($0, 1, 1)
+            work_status  = substr($0, 2, 1)
+
+            if (index_status == "?" && work_status == "?") {
+                untracked++
+            }
+            else {
+                if (index_status != " " && index_status != "?")
+                    staged++
+
+                if (work_status != " " && work_status != "?")
+                    modified++
+            }
+        }
+
+        END {
+            printf "%d %d %d", staged, modified, untracked
+        }
+        '
+    )"
+
+    set -- $counts
+
+    staged="${1:-0}"
+    modified="${2:-0}"
+    untracked="${3:-0}"
+
+    ahead=0
+    behind=0
+
+    # Compare with upstream branch, if one exists.
+    upstream="$(
+        git rev-list \
+            --left-right \
+            --count \
+            'HEAD...@{upstream}' \
+            2>/dev/null
+    )"
+
+    if [ -n "$upstream" ]; then
+        set -- $upstream
+
+        ahead="${1:-0}"
+        behind="${2:-0}"
+    fi
+
+    # Branch name.
+    print -nr -- " ${MAGENTA}git:${CYAN}${branch}${RESET}"
+
+    # Working tree state.
+    if [ "$staged" -eq 0 ] &&
+       [ "$modified" -eq 0 ] &&
+       [ "$untracked" -eq 0 ]; then
+
+        print -nr -- " ${GREEN}✓${RESET}"
+
+    else
+
+        if [ "$staged" -gt 0 ]; then
+            print -nr -- " ${GREEN}+${staged}${RESET}"
+        fi
+
+        if [ "$modified" -gt 0 ]; then
+            print -nr -- " ${YELLOW}~${modified}${RESET}"
+        fi
+
+        if [ "$untracked" -gt 0 ]; then
+            print -nr -- " ${CYAN}?${untracked}${RESET}"
+        fi
+    fi
+
+    # Ahead of upstream.
+    if [ "$ahead" -gt 0 ]; then
+        print -nr -- " ${GREEN}↑${ahead}${RESET}"
+    fi
+
+    # Behind upstream.
+    if [ "$behind" -gt 0 ]; then
+        print -nr -- " ${RED}↓${behind}${RESET}"
+    fi
+}
+
+
+# ------------------------------------------------------------
+# Python virtual environment
+#
+# Example:
+#
+#   py:.venv
+# ------------------------------------------------------------
+
+venv_prompt()
+{
+    typeset venv
+
+    if [ -n "${VIRTUAL_ENV:-}" ]; then
+
+        venv="${VIRTUAL_ENV##*/}"
+
+        print -nr -- \
+            " ${BLUE}py:${venv}${RESET}"
+    fi
+}
+
+
+# ------------------------------------------------------------
+# SSH indicator
+#
+# Normal SSH sessions have SSH_* environment variables.
+#
+# "su -" removes those variables, so who -m is used as a
+# fallback to determine whether this terminal originated from
+# a remote login.
+# ------------------------------------------------------------
+
+ssh_prompt()
+{
+    if [ -n "${SSH_CONNECTION:-}" ] ||
+       [ -n "${SSH_CLIENT:-}" ] ||
+       [ -n "${SSH_TTY:-}" ]; then
+
+        print -nr -- \
+            " ${DARK_GRAY}[SSH]${RESET}"
+
+        return
+    fi
+
+    # Fallback after "su -".
+    if who -m 2>/dev/null | grep -q '('; then
+
+        print -nr -- \
+            " ${DARK_GRAY}[SSH]${RESET}"
+    fi
+}
+
+
+# ------------------------------------------------------------
+# Build prompt
+# ------------------------------------------------------------
+
+build_prompt()
+{
+    typeset exit_code="$1"
+    typeset prompt_dir
+
+    prompt_dir="$PWD"
+
+    # Replace $HOME with ~.
+    case "$prompt_dir" in
+
+        "$HOME")
+            prompt_dir="~"
+            ;;
+
+        "$HOME"/*)
+            prompt_dir="~${prompt_dir#$HOME}"
+            ;;
+    esac
+
+
+    # --------------------------------------------------------
+    # First line
+    # --------------------------------------------------------
+
+    # user@hostname
+    print -nr -- \
+        "${USER_COLOR}${PROMPT_USER}@${PROMPT_HOST}${RESET}"
+
+    # Current directory
+    print -nr -- \
+        " ${BOLD_BLUE}${prompt_dir}${RESET}"
+
+    # Git information
+    git_prompt
+
+    # Python virtual environment
+    venv_prompt
+
+    # SSH indicator
+    ssh_prompt
+
+    # Previous command failed.
+    if [ "$exit_code" -ne 0 ]; then
+
+        print -nr -- \
+            " ${BOLD_RED}[exit:${exit_code}]${RESET}"
+    fi
+
+
+    # --------------------------------------------------------
+    # Second line
+    #
+    # Root:
+    #   #
+    #
+    # Normal user:
+    #   $
+    # --------------------------------------------------------
+
+    print -nr -- "
+${USER_COLOR}${PROMPT_CHAR}${RESET} "
+}
+
+
+# Don't let Python virtualenv modify PS1 itself.
+export VIRTUAL_ENV_DISABLE_PROMPT=1
+
+
+# ------------------------------------------------------------
+# Enable prompt
+# ------------------------------------------------------------
+
+PS1='$(build_prompt $?)'