setup_bash.sh

#!/bin/sh
#
# Bash and Vim Environment Setup Script
# =====================================
#
# Purpose:
# Automates the setup of a Bash environment with practical defaults, adhering
# to XDG Base Directory standards, ensuring clean, isolated, and maintainable configurations.
#
# Features:
# - Configures Bash with custom `.bashrc` and `.profile`.
# - Sets up Vim with vim-plug for modern plugin management.
# - Supports quiet mode (-q) for automated scripts.
# - Includes cleanup option to remove old configurations and history files.
# - Fully POSIX-compliant for compatibility with minimal environments.
# 
# Usage:
#  sh -c "$(curl -fsSL https://gist.githubusercontent.com/Raiu/579a993b9c5dcda726bf561ffc9df3f4/raw/setup_bash.sh)"
#  sh -c "$(curl -fsSL https://gist.githubusercontent.com/Raiu/579a993b9c5dcda726bf561ffc9df3f4/raw/setup_bash.sh)" -- -q
#  sh -c "$(curl -fsSL https://gist.githubusercontent.com/Raiu/579a993b9c5dcda726bf561ffc9df3f4/raw/setup_bash.sh)" -- -q --clean
#  sh -c "$(curl -fsSL https://gist.githubusercontent.com/Raiu/579a993b9c5dcda726bf561ffc9df3f4/raw/setup_bash.sh)" -- --clean
# 
# Other useful packages:
# bat, fzf,
# Eza:
# curl -sL https://github.com/eza-community/eza/releases/latest/download/eza_x86_64-unknown-linux-gnu.tar.gz | tar xz -C /tmp && sudo mv /tmp/eza /usr/local/bin/eza
#

set -e

XDG_CACHE_HOME="${XDG_CACHE_HOME:-$HOME/.cache}"
XDG_CONFIG_HOME="${XDG_CONFIG_HOME:-$HOME/.config}"
XDG_DATA_HOME="${XDG_DATA_HOME:-$HOME/.local/share}"
BASH_DIR="${XDG_CONFIG_HOME}/bash"
PROFILE="${BASH_DIR}/profile"
BASHRC="${BASH_DIR}/bashrc"
VIM_DIR="${XDG_CONFIG_HOME}/vim"
VIMRC="${VIM_DIR}/vimrc"
VIMRC_MIN="${VIM_DIR}/vimrc.minimal"
CLEANUP_FILES=".bash_history:.bashrc:.bash_profile:.inputrc:.vimrc:.viminfo:.wget-hsts:.lesshst:.sudo_as_admin_successful"

log() { [ "$QUIET" -ne 1 ] && echo "$@"; }
error() { echo "Error: $*" >&2; exit 1; }
exist() { command -v "$1" >/dev/null 2>&1; }

BASHRC_CONTENT=$(
    cat <<'EOF'
# Helpers
_exist() { command -v "$1" >/dev/null 2>&1; }

# Blues: Light (BL1), Medium (BL2), Sky (BL3)
BL1="\[$(tput setaf 12)\]" BL2="\[$(tput setaf 45)\]" BL3="\[$(tput setaf 51)\]"
# Reds: Bright (RD1), Crimson (RD2), Intense (RD3)
RD1="\[$(tput setaf 9)\]" RD2="\[$(tput setaf 160)\]" RD3="\[$(tput setaf 196)\]"
# Greens: Light (GR1), Medium (GR2), Deep (GR3)
GR1="\[$(tput setaf 10)\]" GR2="\[$(tput setaf 40)\]" GR3="\[$(tput setaf 46)\]"
# Yellows/Oranges: Bright Yellow (YL1), Intense Yellow (YL2), Light Orange (OR1), Dark Orange (OR2)
YL1="\[$(tput setaf 11)\]" YL2="\[$(tput setaf 226)\]" OR1="\[$(tput setaf 208)\]" OR2="\[$(tput setaf 202)\]"
# Purples: Bright (PR1), Deep (PR2), Vibrant (PR3)
PR1="\[$(tput setaf 13)\]" PR2="\[$(tput setaf 165)\]" PR3="\[$(tput setaf 201)\]"
# White/Black: Bright White (WH1), Light White (WH2), Light Gray (GY1), Dark Gray (GY2), Black (BK1)
WH1="\[$(tput setaf 231)\]" WH2="\[$(tput setaf 15)\]" GY1="\[$(tput setaf 250)\]" GY2="\[$(tput setaf 240)\]" BK1="\[$(tput setaf 232)\]"
# Reset
RES="\[$(tput sgr0)\]"

# Set XDG Base Directories
export XDG_CONFIG_HOME="${XDG_CONFIG_HOME:-$HOME/.config}"
export XDG_DATA_HOME="${XDG_DATA_HOME:-$HOME/.local/share}"
export XDG_CACHE_HOME="${XDG_CACHE_HOME:-$HOME/.cache}"
export XDG_STATE_HOME="${XDG_STATE_HOME:-$HOME/.local/state}"
mkdir -p "${XDG_CACHE_HOME}/bash" "${XDG_DATA_HOME}/bash" "${XDG_STATE_HOME}/bash" || {
    echo "Failed to create directories" >&2
}

# Other exports
export FZF_DEFAULT_OPTS="--height 40% --layout=reverse --border"

# General Environment Settings
umask 022
shopt -s checkwinsize
shopt -s autocd
shopt -s globstar

# History Configuration
HISTFILE="${XDG_STATE_HOME}/bash/history"
[ ! -f "$HISTFILE" ] && touch "$HISTFILE"
HISTSIZE=1000
HISTFILESIZE=2000
shopt -s histappend
export HISTCONTROL=ignoredups:erasedups

# Enable Completion
if [ -f "$XDG_CONFIG_HOME/bash_completion" ]; then
    . "$XDG_CONFIG_HOME/bash_completion"
elif [ -f "/usr/share/bash-completion/bash_completion" ]; then
    . "/usr/share/bash-completion/bash_completion"
fi
if _exist fzf; then
    fzf_kbpath=$(find /usr/share -type f -name "key-bindings.bash" 2>/dev/null | head -n 1)
    [ -f "$fzf_kbpath" ] && source "$fzf_kbpath"
fi

# Binds
if [ "$PS1" ] ; then
    bind '"\C-@": " \C-u$(fzf)\e\C-e\er"' # open fzf with ctrl-space
    bind 'set show-all-if-ambiguous on'
    bind 'TAB:menu-complete'
fi

# Prompt
LAST_DIR=""
chpwd() { [[ "$LAST_DIR" != "$PWD" ]] && LAST_DIR="$PWD" && ls; }
prompt() {
    PS1="\n${OR1}\u${RES}@${BL1}\h${RES}: ${BL3}\w${RES}\n"
    [[ $_ecode -eq 0 ]] && PS1+="${GR3}→${RES} " || PS1+="${RD3}→${RES} "
}
export PROMPT_COMMAND='_ecode=$?; history -a; history -c; history -r; chpwd; prompt'

# Functions
batman() {
    _exist bat || { echo "Error: 'bat' is not installed." >&2; return 1; }
    [[ -z "$1" ]] && { echo "Usage: batman <command>" >&2; return 1; }
    man "$1" | col -bx | bat --paging=always --language=man
}

# Alias Definitions
_exist "batcat" && alias bat="batcat"
_exist "fdfind" && alias fd="fdfind"
if _exist "eza"; then
    alias ls='eza --icons --group-directories-first'
    alias lsa='eza -a --icons --group-directories-first'
    alias lt='eza -T --group-directories-first --icons --git'
    alias lta='eza -Ta --group-directories-first --icons --git'
    alias ll='eza -lmh --group-directories-first --color-scale --icons'
    alias la='eza -lamhg --group-directories-first --color-scale --icons --git'
    alias laa='eza -lamhg@ --group-directories-first --color-scale --icons --git'
    alias lx='eza -lbhHigUmuSa@ --group-directories-first --color-scale --icons --git --time-style=long-iso'
else
    alias ls='ls -h --group-directories-first --color=auto'
    alias lsa='ls -Ah --group-directories-first --color=auto'
    alias ll='ls -lh --group-directories-first --color=auto'
    alias la='ls -lAh --group-directories-first --color=auto'
fi
alias c='clear'
alias h='history'
alias ..='cd ..'
alias ...='cd ../..'
alias md='mkdir -p'
alias rd='rmdir'
alias egrep='grep -E --color=auto --exclude-dir={.bzr,CVS,.git,.hg,.svn,.idea,.tox}'
alias fgrep='grep -F --color=auto --exclude-dir={.bzr,CVS,.git,.hg,.svn,.idea,.tox}'
alias wget='wget --no-hsts'
alias bed='vim ${XDG_CONFIG_HOME}/bash/bashrc'
alias bre='source ${XDG_CONFIG_HOME}/bash/bashrc'
alias ved='vim ${XDG_CONFIG_HOME}/vim/vimrc'
alias vim.recover='vim -u ${XDG_CONFIG_HOME}/vim/vimrc.minimal -U NONE -i NONE ${XDG_CONFIG_HOME}/vim/vimrc'
alias minvim='vim -u ${XDG_CONFIG_HOME}/vim/vimrc.minimal -U NONE -i NONE'
EOF
)


PROFILE_CONTENT=$(
    cat <<'EOF'
# XDG Base Directory Specification
export XDG_CONFIG_HOME="${XDG_CONFIG_HOME:-$HOME/.config}"
export XDG_DATA_HOME="${XDG_DATA_HOME:-$HOME/.local/share}"
export XDG_CACHE_HOME="${XDG_CACHE_HOME:-$HOME/.cache}"
export XDG_STATE_HOME="${XDG_STATE_HOME:-$HOME/.local/state}"

# Ensure XDG directories exist
mkdir -p "${XDG_CONFIG_HOME}/bash" "${XDG_DATA_HOME}/bash"\
         "${XDG_CACHE_HOME}/bash" "${XDG_STATE_HOME}/bash"

# Ensure PATH includes common directories
old_path=$PATH:"$HOME/.local/bin:/usr/local/bin:/usr/local/sbin:/usr/bin:/bin:/usr/sbin:/sbin"
new_path=""
for dir in $(echo "$old_path" | tr ':' '\n' | sed '1!G;h;$!d'); do
    case ":$new_path:" in
        *":$dir:"*) ;;
        *) new_path="$dir${new_path:+:$new_path}" ;;
    esac
done
export PATH="$new_path"

# Source interactive shell configurations only if the shell is Bash and interactive
if [ -n "$BASH" ] && [ "$-" != "${-#*i}" ]; then
    if [ -f "$XDG_CONFIG_HOME/bash/bashrc" ]; then
        . "$XDG_CONFIG_HOME/bash/bashrc"
    elif [ -f "$HOME/.bashrc" ]; then
        . "$HOME/.bashrc"
    fi
fi

# VIM
export VIMINIT='let $MYVIMRC = $XDG_CONFIG_HOME . "/vim/vimrc" | source $MYVIMRC'
EOF
)

VIMRC_CONTENT=$(
    cat <<'EOF'
" ====== XDG Compliance ======
let $XDG_CONFIG_HOME = exists('$XDG_CONFIG_HOME') ? $XDG_CONFIG_HOME : expand('~/.config')
let $XDG_DATA_HOME = exists('$XDG_DATA_HOME') ? $XDG_DATA_HOME : expand('~/.local/share')
let $VIMDOTDIR = $XDG_CONFIG_HOME . '/vim'
let $VIMDATADIR = $XDG_DATA_HOME . '/vim'

" ====== General Settings ======
syntax on                             " Enable syntax highlighting
filetype plugin indent on             " Enable filetype detection and indentation
set clipboard=unnamedplus             " Use system clipboard
set hlsearch                          " Highlight search results
set ignorecase smartcase              " Case-insensitive search unless uppercase is used
set incsearch                         " Incremental search
set nocursorline                      " Highlight the current line
set number relativenumber             " Show line numbers
set mouse=a                           " Enable mouse support
set scrolloff=5                       " Keep 5 lines visible when scrolling
set showmode                          " Display mode in status line
set sidescrolloff=5                   " Horizontal scrolling offset
set splitbelow splitright             " Open splits to the right and below
set tabstop=4 shiftwidth=4 expandtab  " Use spaces instead of tabs
set timeoutlen=500                    " 500ms for mappings
set ttimeoutlen=10                    " Faster key timeout
set updatetime=300                    " Faster updates for a smoother experience

" ====== Directories and Files ======
silent! call mkdir($VIMDATADIR . '/backup', 'p')
silent! call mkdir($VIMDATADIR . '/undo', 'p')
silent! call mkdir($VIMDATADIR . '/swap', 'p')

set backupdir=$VIMDATADIR/backup//
set undodir=$VIMDATADIR/undo//
set directory=$VIMDATADIR/swap//
set backup
set undofile
set viminfo+=n$VIMDATADIR/viminfo

" ====== Colorscheme ======
colorscheme slate
set background=dark

" ====== Statusline ======
set statusline=%<%f\ %h%m%r\ %y\ [%{&fileformat}]\ [%{&fileencoding}]\ %=%-14.(%l,%c%V%)\ %P
set laststatus=2

" ====== Mode Settings ======
" Insert mode cursorline
au InsertEnter * set cul
au InsertLeave * set nocul
" Insert mode lin shape
let &t_SI = "\e[6 q"
let &t_EI = "\e[2 q"

" ====== Key Mappings ======
let mapleader = ","
" Edit and Source vimrc
nnoremap <leader>ev :e $MYVIMRC<CR>
nnoremap <leader>sv :source $MYVIMRC<CR>
" Toggle between Normal and Insert mode
nnoremap <C-@> a
inoremap <C-@> <Esc>
vnoremap <C-@> <Esc>
" Easy file saving and quitting
nnoremap <leader>w :w<CR>
nnoremap <leader>q :q<CR>
" Save all files and Quit all files
nnoremap <leader>W :wa<CR>
nnoremap <leader>Q :qa<CR>
" Clear search highlights
nnoremap <leader>h :nohlsearch<CR>
" Window navigation
nnoremap <C-h> <C-w>h
nnoremap <C-j> <C-w>j
nnoremap <C-k> <C-w>k
nnoremap <C-l> <C-w>l
" Split management
nnoremap <leader>v :vsplit<CR>
nnoremap <leader>s :split<CR>
" Quick search and replace
nnoremap <leader>r :%s//g<Left><Left>
" Yank selected text into register (z)
vnoremap <leader>y "zy
" Search-replace using text from register (z)
nnoremap <leader>c :<C-u>let @/ = escape(@z, '/\\')<CR>:%s/<C-r>=@z<CR>/<C-r>=@z<CR>/g<Left><Left>
vnoremap <leader>c :<C-u>let @/ = escape(@z, '/\\')<CR>:'<,'>s/<C-r>=@z<CR>/<C-r>=@z<CR>/g<Left><Left>
" Search-replace using selection as search pattern
vnoremap <leader>r "hy:let @/ = escape(@h, '/\\.*^$[]~')<CR>:%s/<C-r>=@/<CR>/<C-r>=@/<CR>/g<Left><Left>
" edit or source vimrc
nnoremap <Leader>e :edit $MYVIMRC<CR>
" vv for Visual Character mode
nnoremap vv v
vnoremap vv v
" vb for Visual Block mode
nnoremap vb <C-v>
vnoremap vb <C-v>
" Manual trimming for all file types
nnoremap <leader>t :silent! %s/\s\+$//e<CR>:echo "Trailing whitespace removed!"<CR>
" Toggle search hl
nnoremap <F2> :set hlsearch!<CR>:echo "Search hl " . (&hlsearch ? "enabled" : "disabled")<CR>
" Show list of open buffers
nnoremap <F3> :ls<CR>:b
" Toggle file explorer
nnoremap <F4> :Lexplore<CR>
" Cycle buffers (silent)
nnoremap <F5> :silent! bnext<CR>:echo "Next buffer: " . bufname('%')<CR>
nnoremap <F6> :silent! bprev<CR>:echo "Prev buffer: " . bufname('%')<CR>

" ====== Functions ======

" ====== Autocommands ======
if has("autocmd")
    " Automatically source vimrc on save
    autocmd! BufWritePost $MYVIMRC silent! source $MYVIMRC | redraw! | echo "vimrc sourced"
    " Automatically reload files when changed externally
    autocmd FocusGained,BufEnter * checktime
    " Highlight yanked text
    autocmd TextYankPost * silent! lua vim.highlight.on_yank {higroup="IncSearch", timeout=300}
    " Automatically create parent directories on save
    autocmd BufWritePre * call mkdir(expand('<afile>:p:h'), 'p')
    " Trim trailing whitespace on save for specific file types
    autocmd BufWritePre *.c,*.cpp,*.h,*.py,*.js,*.ts,*.html,*.css,*.json,*.yml,*.yaml,*.sql,*.sh,*.go %s/\s\+$//e
endif

" ====== Miscellaneous ======
EOF
)

VIMRC_MIN_CONTENT=$(
    cat <<'EOF'
filetype plugin indent on
syntax on
set backspace=indent,eol,start
set hlsearch
set ignorecase smartcase
set nocompatible
set noerrorbells
set nowrap
set number
set ruler
set tabstop=4 shiftwidth=4 expandtab
EOF
)

symlink() {
    [ ! -d "$(dirname "$2")" ] && mkdir -p "$(dirname "$2")"
    [ -L "$2" ] && [ "$(readlink -f "$2")" = "$(readlink -f "$1")" ] && return 0
    [ -e "$2" ] && [ ! -L "$2" ] && mv "$2" "$2.bak"
    ln -sf "$1" "$2"
}

download_file() {
    if exist curl; then
        curl -sSfLo "$2" "$1" || error "Failed to download $1 with curl."
    elif exist wget; then
        wget -qO "$2" "$1" || error "Failed to download $1 with wget."
    else
        error "curl or wget is required."
    fi
}

create_xdg_dirs() {
    mkdir -p "${BASH_DIR}" "${XDG_CACHE_HOME}/bash" "${XDG_DATA_HOME}/bash" \
			 "${VIM_DIR}" "${XDG_CACHE_HOME}/vim" "${XDG_DATA_HOME}/vim"
}

deploy_bash() {
    echo "${BASHRC_CONTENT}" >"${BASHRC}"
    echo "${PROFILE_CONTENT}" >"${PROFILE}"
    symlink "${PROFILE}" "$HOME/.profile"
}

deploy_vim() {
    echo "${VIMRC_CONTENT}" >"${VIMRC}"
    echo "${VIMRC_MIN_CONTENT}" >"${VIMRC_MIN}"
}

check_dependencies() {
    exist bash || error "bash is required but not installed."
    exist vim || error "vim is required but not installed."
    exist curl || exist wget || error "curl or wget is required but neither is installed."
}

cleanup() {
    log "Cleaning up old configurations and history files..."
    echo "$CLEANUP_FILES" | tr ':;' '\n' | while IFS= read -r file; do
        target="$HOME/$file"
        if [ -e "$target" ]; then
            rm -rf "$target" && log "Removed: $file"
        fi
    done
    log "Cleanup complete."
}

prompt_cleanup() {
    printf "Do you want to clean up old configurations and history files? [y/N]: "
    read -r response
    case "$response" in
    [yY][eE][sS] | [yY]) cleanup ;;
    *) log "Skipping cleanup." ;;
    esac
}

main() {
    QUIET=0
    CLEANUP=0
    for arg in "$@"; do
        case "$arg" in
        -q | --quiet) QUIET=1 ;;
        -c | --clean) CLEANUP=1 ;;
        *) error "Invalid argument: $arg" ;;
        esac
    done

    log "Setting up..."
    log "* Verifying dependencies..."
    check_dependencies
    log "* Creating XDG directories..."
    create_xdg_dirs
    log "* Deploying Bash configuration..."
    deploy_bash
    log "* Installing Vim..."
    deploy_vim

    if [ "$CLEANUP" -eq 1 ]; then
        cleanup
    elif [ "$QUIET" -eq 0 ]; then
        prompt_cleanup
    fi

    log "Setup complete! Restart your shell or run: exec bash"
}

main "$@"