#!/bin/bash
## brethil's dotfiles installation script
## 20 June 2016

# Get the location for the dotfiles
DOTFILES=$PWD

# Install packages
# vim, zsh
# antigen: zsh plugin manager
# grc: generic colourizer, colors output of any command
# ccze: similar to the above
# byobu: configuration/wrapper for tmux
# bmon: bandwidth monitor, monitors bandwith usage, shows graph
# mtr: mytraceroute, traceroute tool
# pv: pipe view, monitor the progress of data through a pipe
# byobu: tmux wrapper
# htop:  like top, but bettah
PACKAGES="vim zsh antigen git grc ccze bmon mtr pv tmux byobu htop" # TODO: add bat

function setup_git {
    # set up some git stuff
    git config --global pull.ff only
    git config --global merge.ff only
}

function install_vimrc {
    # Install vimrc from github.com/amix/vimrc
    git clone "https://github.com/amix/vimrc.git" "$HOME/.vim_runtime" && sh "$HOME/.vim_runtime/install_awesome_vimrc.sh" || return 1
}

function setup_vim {
    ln -s $DOTFILES/my_configs.vim $HOME/.vim_runtime/my_configs.vim
}

# Add an ssh config file with:
# - Connection multiplexer for faster multiple connections
# - Keep connections alive (avoid timeout disconnections)
function create_ssh_config {
    echo "# Configuring ssh..."

    ssh_config="$HOME/.ssh/config"

    if [ ! -f $HOME/.ssh/id_rsa ]; then
        echo "Creating ssh key (4096bit)..."

        echo "Enter ssh-key comment (leave empty for default: user@host)"
        read comment
        if [[ $comment ]]; then
            ssh-keygen -t rsa -b 4096 -C $comment
        else
            ssh-keygen -t rsa -b 4096
        fi
        # fix permissions
        chmod 0700 "$HOME/.ssh"
    fi

    if [[ -f $ssh_config ]]; then
        until [[ $modifyssh == "y" || $modifyssh == "n" ]]; do
            echo "Do you want to modify the existing ssh config? (New values will be appended) (y/n)"
            read modifyssh
        done
    fi

    exec 3>&1 # save stdout file descriptor

	# add the ssh rc that symlinks the used SSH_AUTH_SOCK. This will be executed on every ssh login.
	# The idea is that if the user is logging in using ssh -A, the symlink will point to the correct
	# location of the ssh auth socket and the remote ssh agent will be used.
    # SSH_AUTH_SOCK is declared in brethil_dotfile.sh
    exec 1>>~/.ssh/rc
	echo '#!/bin/bash'
	echo 'if test "$SSH_AUTH_SOCK" ; then'
    echo '	ln -sf $SSH_AUTH_SOCK ~/.ssh/ssh_auth_sock'
	echo 'fi   '
	chmod 755 ~/.ssh/rc

    exec 1>>$ssh_config # redirect everything below to the $ssh_config file
    if [[ "$modifyssh" == "n" ]]; then
        echo "Did not modify $ssh_config."
        exec 1>&3 # restore stdout
        return
    fi
    echo "# brethil's dotfiles setup start"
    echo 'TCPKeepAlive=yes'
    echo 'ServerAliveCountMax=6'
    echo
    echo "## Uncomment to enable compression for all ssh sessions"
    echo '#Compression=yes'
    echo
    echo '## Uncomment the following to enable ssh ControlMaster and ssh session persistence'
    echo '#ControlMaster auto'
    echo '#ControlPath /tmp/%r@%h:%p'
    echo '#ControlPersist yes'
    echo
    echo 'Host *'
    echo '    ServerAliveInterval 300'
    echo
    echo '## Enable the following if you want to use the rmate textmate remote'
    echo "#Host *"
    echo "#    RemoteForward 52698 localhost:52698"
    echo
    echo '## Enable the following if you want to use a reverse ssh tunnel to use mecp command on remote hosts'
    echo "#Host *"
    echo "#    Remoteforward 2222 localhost:22"
    echo
    echo '# end of brethil dotfiles setup #'

    exec 1>&3 # restore stdout
    echo ".ssh/ssh_config configured. Edit it to enable custom options:"
    echo "- Compression"
    echo "- Remote forwarding  remote:2222->localhost:22 (revere tunnel to scp back to the original host using mecp)"
    echo "# End of ssh config."
}

function fix_annoyances {
    ## Fix scrolling in byobu
    if [[ $(uname) == "Darwin" ]]; then
        sed -i '' 's/set -g terminal-overrides/#set -g terminal-overrides/' /usr/share/byobu/profiles/tmux
    else
        sed -i 's/set -g terminal-overrides/#set -g terminal-overrides/' /usr/share/byobu/profiles/tmux
    fi

    # remove ls from the grc.zsh config: # TODO: fix this on MacOS
    sed 's|ls \\|#ls \\|' /etc/grc.zsh

    # TODO: add iptables, docker to grc.zsh


}


# First setup
function brethil_dotfiles_setup {
    bin="$HOME/bin"
    projects="$HOME/projects"
    git="$HOME/git"
    mkdir -p "$bin" "$projects" "$git" && echo "Created dirs $bin, $projects, $git"

    # Check if running as root, if try using sudo to install packages.
    # If sudo is not installed, launch a shell to try and install it
    if [[ $(id -u) != 0 ]]; then
        if [[ ! -f $(which sudo) ]] ; then
            unset yn
            until [[ $yn == "y" || $yn == "n" ]]; do
                echo "Cannot install new packages without root access. Do you want to try to manually install sudo? (yn) "
                read yn
            done
            if [[ $yn == "y" ]]; then
                echo "Launching an interactive shell. Type exit after installing sudo."
                # Launch bash
                $(which bash)
            else
                echo "Quitting."
                exit 0
            fi
        elif [[ -f $(which sudo) ]]; then
            sudo="sudo "
        fi
    fi

    if [[ $(which apt-get ) ]]; then
        PACKAGES=${PACKAGES/antigen/zsh-antigen/}
        antigen_path=/usr/share/zsh-antigen/antigen.zsh
        install_command="${sudo}apt-get install"
    elif [[ $(which pacman) ]]; then
        pacman -Sy yay # also install the yay aur package managery
        antigen_path=/usr/share/zsh/share/antigen.zsh
        grc_path=/etc/grc.zsh
        install_command="${sudo}yay -Sy"
    elif [[ $(which yum) ]]; then
        antigen_path=/usr/share/zsh/share/antigen.zsh
        install_command="${sudo}yum"
    elif [[ $(which brew) ]]; then
        antigen_path=/usr/local/share/antigen/antigen.zsh
        install_command="${sudo}brew install"
    else
        echo "I do not know how to install the required packages. Quitting."
        exit 0
    fi

    if [[ ! -f $antigen_path ]]; then
        echo "antigen.zsh not found, please set up manually in ~/.zshrc" 1>&2
        exit 0
    fi

    # actually install the packages
    $install_command $PACKAGES

    # prepare .zshrc
    exec 1>&3 # save stdout
    exec 1>$HOME/.zshrc
    echo "source $antigen_path"
    echo -e "\n\n# brethil's dotfiles:"
    # Source antigen
    echo "source $antigen_path"
    echo "DOTFILES=$DOTFILES"
    echo "source \$DOTFILES/brethil_dotfile.sh"
    echo -e "# End of brethil's dotfiles\n\n"

    fix_annoyances
    # Install vim awesomerc (git amix/vimrc)
    install_vimrc && echo "Installed vim awesome rc" || echo "Failed to install vim awesome rc"
    setup_vim
    # Create ssh config
    create_ssh_config
    # git config
    setup_git

    # Symlink brethil.zsh-theme
    ln -s $DOTFILES/brethil.zsh-theme $HOME/.antigen/bundles/robbyrussell/oh-my-zsh/themes/ # TODO: improve this
    # Symlink brethil-minimal.zsh-theme
    ln -s $DOTFILES/brethil-minimal.zsh-theme $HOME/.antigen/bundles/robbyrussell/oh-my-zsh/themes/

    # TODO: powerline?
}



# Setup
brethil_dotfiles_setup

echo "Functions definitions in $DOTFILES/functions.sh (you can add your own functions in ~/.dotfiles_functions)"
echo "Aliases definitions in $DOTFILES/aliases.sh (you can add your own aliases in ~/.dotfiles_aliases)"
echo "Colors are defined in $DOTFILES/colors.sh"

echo "Type . ~/.zshrc to source the new dotfiles, or simply launch another shell. )"