# shellcheck shell=bash

# Return immediately if non-interactive (makes FTP clients happy)
[[ "$-" == *i* ]] || return

##############################################################################
# Customize environment
##############################################################################

export XDG_CACHE_HOME="$HOME/.cache"
export XDG_CONFIG_HOME="$HOME/.config"
export XDG_DATA_HOME="$HOME/.local/share"

export EDITOR="vim"
export INPUTRC="$XDG_CONFIG_HOME/readline/inputrc"
export LANG="en_US.UTF-8"
export LANGUAGE="en_US"
export LC_ALL="en_US.UTF-8"
export LC_CTYPE="en_US.UTF-8"
export LESS="-i -j.49 -M -R -z-2"
export LESSHISTFILE="$XDG_CACHE_HOME/less/history"
export LESSHISTSIZE=1000
export LOCAL_CONFIG="$HOME/.local/etc"
export LOCAL_PREFIX="/usr/local"
if command -v brew &>/dev/null; then
    LOCAL_PREFIX="$(brew --prefix)"
    export HOMEBREW_NO_ANALYTICS=1
    export HOMEBREW_NO_AUTO_UPDATE=1
fi
MANPATH="$(unset MANPATH; manpath)"
export MANPATH
export PAGER=less
export PYTHONSTARTUP="$XDG_CONFIG_HOME/python/startup.py"
# shellcheck disable=SC2016 # This expression is to be interpreted by vim, not bash.
export VIMINIT='let $MYVIMRC="$XDG_CONFIG_HOME/vim/vimrc" | source $MYVIMRC'

##############################################################################
# Customize PATH (and MANPATH)
##############################################################################

# Prevent path_helper from messing with the PATH when starting tmux.
#   See: https://superuser.com/a/583502
# shellcheck disable=SC2123 # PATH is being intentionally manipulated here.
# shellcheck disable=SC1091 # /etc/profile is provided by macOS.
[ "$(uname)" == "Darwin" ] && { PATH=""; source /etc/profile; }

_prepend_path() {   # 1: dir to add, 2: path variable to manipulate
    if [ -d "$1" ] && [ -n "$2" ]; then
        local _path="${!2}"                     # get path variable value
        case ":$_path:" in
            *":$1:"*) :;;                       # dir already in path, noop (:)
            *) _path="$1${_path:+:}$_path";;    # prepend (adding : if not empty)
        esac
        printf -v "$2" "%s" "$_path"            # write back to path variable
    fi
}

# Add custom bin dirs to PATH if they exist and are not already in PATH.
while read -r dir; do _prepend_path "$dir" PATH; done <<EOL
    $LOCAL_PREFIX/bin
    $LOCAL_PREFIX/opt/man-db/libexec/bin
    $LOCAL_PREFIX/opt/coreutils/libexec/gnubin
    $LOCAL_PREFIX/opt/gnu-sed/libexec/gnubin
    $HOME/.local/bin
EOL

# Prepend custom man directories to MANPATH if they exist, so that we get
# correct man page entries when multiple versions of a command are
# available.
while read -r dir; do _prepend_path "$dir" MANPATH; done <<EOL
    $LOCAL_PREFIX/share/man
    $LOCAL_PREFIX/opt/man-db/libexec/man
    $LOCAL_PREFIX/opt/coreutils/libexec/gnuman
    $LOCAL_PREFIX/opt/gnu-sed/libexec/gnuman
    $HOME/.local/share/man
EOL

unset dir

##############################################################################
# Customize shell options & variables
##############################################################################

shopt -s cdspell checkwinsize globstar histappend nocaseglob
set -o noclobber    # Prevent overwriting files with output redirection.

# Eternal bash history (from https://stackoverflow.com/a/19533853)
HISTCONTROL=erasedups
HISTFILESIZE=
HISTSIZE=
HISTTIMEFORMAT="[%F %T] "
HISTFILE="$XDG_CACHE_HOME/bash/history"

# shellcheck disable=SC2034 # these variable are meant for use in shell only
{
    # Color definitions (from http://ethanschoonover.com/solarized)
    # NAME                RGB HEX    SGR  ANSI TERMCOL  XTERM/HEX    L*A*B       RGB          HSB
    # ----                -------    ---  ---- -------  ----------- -----------  -----------  -----------
    Base03=8  Base03_RGB="002B36"  # 1;30   8  brblack  234 #1c1c1c  15 -12 -12    0  43  54  193 100  21
    Base02=0  Base02_RGB="073642"  # 0;30   0  black    235 #262626  20 -12 -12    7  54  66  192  90  26
    Base01=10 Base01_RGB="586E75"  # 1;32  10  brgreen  240 #585858  45 -07 -07   88 110 117  194  25  46
    Base00=11 Base00_RGB="657B83"  # 1;33  11  bryellow 241 #626262  50 -07 -07  101 123 131  195  23  51
    Base0=12  Base0_RGB="839496"   # 1;34  12  brblue   244 #808080  60 -06 -03  131 148 150  186  13  59
    Base1=14  Base1_RGB="93A1A1"   # 1;36  14  brcyan   245 #8a8a8a  65 -05 -02  147 161 161  180   9  63
    Base2=7   Base2_RGB="EEE8D5"   # 0;37   7  white    254 #e4e4e4  92 -00  10  238 232 213   44  11  93
    Base3=15  Base3_RGB="FDF6E3"   # 1;37  15  brwhite  230 #ffffd7  97  00  10  253 246 227   44  10  99
    Yellow=3  Yellow_RGB="B58900"  # 0;33   3  yellow   136 #af8700  60  10  65  181 137   0   45 100  71
    Orange=9  Orange_RGB="CB4B16"  # 1;31   9  brred    166 #d75f00  50  50  55  203  75  22   18  89  80
    Red=1     Red_RGB="DC322F"     # 0;31   1  red      160 #d70000  50  65  45  220  50  47    1  79  86
    Magenta=5 Magenta_RGB="D33682" # 0;35   5  magenta  125 #af005f  50  65 -05  211  54 130  331  74  83
    Violet=13 Violet_RGB="6C71C4"  # 1;35  13  brmagenta 61 #5f5faf  50  15 -45  108 113 196  237  45  77
    Blue=4    Blue_RGB="268BD2"    # 0;34   4  blue      33 #0087ff  55 -10 -45   38 139 210  205  82  82
    Cyan=6    Cyan_RGB="2AA198"    # 0;36   6  cyan      37 #00afaf  60 -35 -05   42 161 152  175  74  63
    Green=2   Green_RGB="859900"   # 0;32   2  green     64 #5f8700  60 -20  65  133 153   0   68 100  60

    PS1_DEFAULT=$(tput setaf $Cyan)     # user@host color for local sessions
    PS1_SSH=$(tput setaf $Yellow)       # user@host color in SSH session
    PS1_ROOT=$(tput setaf $Orange)      # user@host color if logged in as root
    PS1_PWD=$(tput setaf $Blue)         # PWD color
    PS1_EXIT=$(tput setaf $Red)         # color for last exit code if non-zero
    PS1_GIT=$(tput setaf $Green)        # color for git branch
    PS1_VENV=$(tput setaf $Violet)      # color for python virtual env
    PS1_JOBS=$(tput setaf $Magenta)     # color for background jobs
    PS1_SEP=" > "                       # separator between prompt parts
    PS1_SEP_COLOR=""                    # is set in __update_colors
    PS1_RST=$(tput sgr0)

    GIT_PS1_SHOWDIRTYSTATE=1
    GIT_PS1_SHOWSTASHSTATE=1
    GIT_PS1_SHOWUNTRACKEDFILES=1
    GIT_PS1_SHOWUPSTREAM=verbose
}

PROMPT_COMMAND=__ps1_set
PS2="... "

__ps1_set() {
    local exit=$?
    local sep="$PS1_SEP_COLOR$PS1_SEP"

    local host=$PS1_DEFAULT
    [ -n "$SSH_CLIENT" ] && host=$PS1_SSH
    [ $EUID -eq 0 ] && host=$PS1_ROOT

    local prompt=">>>>>>>>>>"
    [ $EUID -eq 0 ] && prompt="##########"

    local ps=()
    [ $exit -ne 0 ] && ps+=("$PS1_EXIT$exit")
    ps+=("$host\u@\h")
    ps+=("$PS1_PWD\w")
    type __git_ps1 && __git_ps1 '' '' "$PS1_GIT%s" && [ -n "$PS1" ] && ps+=("$PS1")
    [ -n "$VIRTUAL_ENV" ] && ps+=("$PS1_VENV${VIRTUAL_ENV##*/}")
    local j="\j" && [ "${j@P}" -gt 0 ] && ps+=("$PS1_JOBS${j@P} bg")

    printf -v PS1 "$sep%s" "${ps[@]:1}"
    PS1="\n${ps[0]}$PS1$PS1_RST\n${prompt:0:$SHLVL} "
} &>/dev/null

##############################################################################
# Customize shell aliases
##############################################################################

# ls:  make `ls` group directories first if supported.
# lsc: force `ls` to use color output (e.g. for piping into `less`).
if ls --group-directories-first --color=auto &>/dev/null 2>&1; then
    # GNU ls
    alias ls="ls -hF --group-directories-first --color=auto"
    alias lsc="ls --color=always"
else
    # BSD ls (e.g. macOS)
    alias ls="ls -hF -G"
    alias lsc="/usr/bin/env CLICOLOR_FORCE=1 ls"
fi

alias la="ls -a"
alias ll="ls -l"
alias lla="ls -la"
alias llc="lsc -l"
alias llac="lsc -la"

alias grep="grep --color=auto"
alias egrep="egrep --color=auto"
alias fgrep="fgrep --color=auto"
alias path='echo $PATH | tr -s ":" "\n"'
alias mpath='echo $MANPATH | tr -s ":" "\n"'
alias timer='echo "Timer started. Stop with Ctrl-D." && date && time cat && date'

alias tmux='tmux -f "$XDG_CONFIG_HOME/tmux/tmux.conf"'

# Head and tail as much as fits on screen
alias head='head -n $((${LINES:-15}-5))'
alias tail='tail -n $((${LINES:-15}-5))'

# A few options to get public IP address on command line. The dig solution
# below using the OpenDNS resolver doesn't work when connected to
# ExpressVPN because all DNS requests are handled by the ExpressVPN DNS
# servers and the OpenDNS DNS resolver is blocked.
alias ipinfo="curl -s ipinfo.io"
alias myip="curl -s https://ifconfig.co"
#alias myip="curl -s https://ifconfig.me"
#alias myip="dig +short myip.opendns.com @resolver1.opendns.com"

alias light='_update_colors light'
alias dark='_update_colors dark'

##############################################################################
# Terminal color management
##############################################################################

# Useful terminal control sequences:
#
# Sequence  Abbrev  Description
# -----     -----   -----------------------------
# ESC P     DCS     Device Control String
# ESC [     CSI     Control Sequence Introducer
# ESC \     ST      String Terminator
# ESC ]     OSC     Operating System Control
#
#
# More info at:
#   * https://www.xfree86.org/4.8.0/ctlseqs.html
#   * https://vt100.net/
#   * https://iterm2.com/utilities/imgcat

# In tmux, OSC sequences can be forwarded to the underlying terminal by:
#   * Wrapping the sequence with `DCS tmux; <sequence> ST`
#   * Replacing ESC in <sequence> with ESC ESC.
_osc_start() {
    if [ -n "$TMUX" ]; then
        printf "\ePtmux;\e\e]"
    else
        printf "\e]"
    fi
}

# Either ST or BEL (\a) can be used to end an OSC sequence. However, tmux
# requires ST to end its wrapping DCS.
_osc_end() {
    if [ -n "$TMUX" ]; then
        printf "\a\e\x5c"       # 0x5c == backslash
    else
        printf "\a"
    fi
}

_update_colors() {
    export BACKGROUND="$1"

    if [ "$BACKGROUND" = "light" ]; then
        _set_terminal_colors $Base01_RGB $Base3_RGB $Red_RGB    # fg bg cursor
        PS1_SEP_COLOR=$(tput setaf $Base1)
    else
        _set_terminal_colors $Base1_RGB $Base03_RGB $Red_RGB    # fg bg cursor
        PS1_SEP_COLOR=$(tput setaf $Base01)
    fi

    if [ -n "$TMUX" ] && [ -f "$XDG_CONFIG_HOME/tmux/tmux-colors.conf" ]; then
        tmux set-environment -g BACKGROUND "$BACKGROUND"
        tmux source-file "$XDG_CONFIG_HOME/tmux/tmux-colors.conf"
    fi

    local ls_colors="$HOME/.config/dircolors/solarized-$BACKGROUND"
    if type dircolors &>/dev/null && [ -f "$ls_colors" ]; then
        eval "$(dircolors "$ls_colors")"
    fi
}

_set_terminal_colors() {    # 1: foreground, 2: background, 3: cursor
    if [ -n "$ITERM_SESSION_ID" ]; then # iTerm2
        _set_iterm2_colors "$1" "$2" "$3"
    else # assume xterm
        _set_xterm_colors "$1" "$2" "$3"
    fi
}

# Documentation for iTerm2 at
# https://iterm2.com/documentation-escape-codes.html
# under the heading "Change the color palette".
_set_iterm2_colors() {    # 1: foreground, 2: background, 3: cursor
    local fg="$1" bg="$2" cursor="$3"
    local key rgb
    while read -r key rgb; do
        _osc_start
        printf "1337;SetColors=%s=%s" "$key" "${rgb}"
        _osc_end
    done <<EOL
        black       $Base02_RGB
        red         $Red_RGB
        green       $Green_RGB
        yellow      $Yellow_RGB
        blue        $Blue_RGB
        magenta     $Magenta_RGB
        cyan        $Cyan_RGB
        white       $Base2_RGB
        br_black    $Base03_RGB
        br_red      $Orange_RGB
        br_green    $Base01_RGB
        br_yellow   $Base00_RGB
        br_blue     $Base0_RGB
        br_magenta  $Violet_RGB
        br_cyan     $Base1_RGB
        br_white    $Base3_RGB
        fg          $fg
        bg          $bg
        bold        $fg
        selfg       $Base2_RGB
        selbg       $Base01_RGB
        curfg       $cursor
        curbg       $cursor
        link        $Cyan_RGB
EOL
    _osc_start
    printf "1337;CursorShape=2"     # set cursor shape to underline
    _osc_end
}

# Documentation for xterm at https://www.xfree86.org/4.8.0/ctlseqs.html
# under the heading "Operating System Controls".
_set_xterm_colors() {    # $1 foreground, $2 background, $3 cursor
    local fg="$1" bg="$2" cursor="$3"
    local c rgb Ps
    while read -r c rgb; do
        # Send sequence OSC Ps BEL
        # where Ps   -> 4;c;spec
        #       c    -> index of the ANSI color to change [0..15]
        #       spec -> RGB value of color as rgb:RR/GG/BB
        _osc_start
        printf "4;%s;rgb:%s/%s/%s" "$c" "${rgb:0:2}"  "${rgb:2:2}" "${rgb:4:2}"
        _osc_end
    done <<EOL
        0  $Base02_RGB
        1  $Red_RGB
        2  $Green_RGB
        3  $Yellow_RGB
        4  $Blue_RGB
        5  $Magenta_RGB
        6  $Cyan_RGB
        7  $Base2_RGB
        8  $Base03_RGB
        9  $Orange_RGB
        10 $Base01_RGB
        11 $Base00_RGB
        12 $Base0_RGB
        13 $Violet_RGB
        14 $Base1_RGB
        15 $Base3_RGB
EOL
    while read -r Ps rgb; do
        # Send sequence OSC Ps ; Pt BEL
        # where Ps -> foreground (10), background (11), or cursor (12)
        #       Pt -> RGB value of color as rgb:RR/GG/BB
        _osc_start
        printf "%s;rgb:%s/%s/%s" "$Ps" "${rgb:0:2}"  "${rgb:2:2}" "${rgb:4:2}"
        _osc_end
    done <<EOL
        10 $fg
        11 $bg
        12 $cursor
EOL
}

##############################################################################
# Add shell functions
##############################################################################

tree() { command tree --dirsfirst -FI '.git|Spotlight-V100|.fseventsd' "$@"; }

ltree() { tree -C "$@" | less -R; }

# Combined mkdir and cd
mkcd() { mkdir -p -- "$1" && cd -P -- "$1" || return; }

# Colorized `man`
man() {
    local rst standout bold underline

    rst=$(tput sgr0)
    if [ "$BACKGROUND" = "light" ]; then
        standout=$(tput -S      <<<"$(echo -e "setaf $Base3\nsetab $Cyan")")
        bold=$(tput -S          <<<"$(echo -e "setaf $Blue")")
        underline=$(tput -S     <<<"$(echo -e "setaf $Base02\nsmul")")
    else
        standout=$(tput -S      <<<"$(echo -e "setaf $Base03\nsetab $Cyan")")
        bold=$(tput -S          <<<"$(echo -e "setaf $Yellow")")
        underline=$(tput -S     <<<"$(echo -e "setaf $Base3\nsmul")")
    fi

    LESS_TERMCAP_so=$standout   \
    LESS_TERMCAP_md=$bold       \
    LESS_TERMCAP_us=$underline  \
    LESS_TERMCAP_se=$rst        \
    LESS_TERMCAP_me=$rst        \
    LESS_TERMCAP_ue=$rst        \
    GROFF_NO_SGR=1              \
    command man "$@"
}

solarized() {
    local rst name name_rgb rgb fg bg

    rst=$(tput sgr0)
    for name in Red Orange Yellow Green Cyan Blue Violet Magenta Base{0{3..0},{0..3}}
    do
        name_rgb=${name}_RGB
        i=
        rgb=${!name_rgb}
        fg=$(tput setaf "${!name}")
        bg=$(tput setab  "${!name}")
        printf "$bg%6s$rst $fg#$rgb %2d $name$rst\n" ''  "${!name}"
    done
}

# Print all 256 colors
colortest() {
    local i j rst
    rst=$(tput sgr0)
    for i in $(seq 0 15); do
        for j in $(seq 0 15); do
            local n=$(( 16 * i + j ))
            printf "$(tput setab $n)  %3d  " $n
        done
        echo "$rst"
    done
}

##############################################################################
# Run external customizations
##############################################################################

stty -ixon # disable ctrl-s and ctrl-q
_update_colors "${BACKGROUND:-dark}"

# shellcheck disable=SC1090
while read -r f; do [ -f "$f" ] && source "$f"; done <<EOF
    /usr/share/bash-completion/bash_completion
    $LOCAL_CONFIG/bash/profile
EOF
unset f