Add web-based installer

This should allow my dotfiles to be installed by simply running curl and piping into bash

install.sh

@@ -1,66 +1,101 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
-# This file will attempt to automatically configure and install my dotfiles
-# This assumes that the following are already installed and in the PATH; perhaps we will attempt to auto-install them in the future
-# tmux
-# vim
-# zsh
-# curl
-# git
-# php 5.3 or greater
+# This ensures that the entire script is downloaded before execution
+{
+
+# Change this url to point to your repo if you made customizations
+repourl="git://github.com/alopexc0de/dotfiles.git"
+
+# Exit the script if any errors are encountered
+set -e
+
+basedir=$HOME/dotfiles
+bindir=$HOME/bin
+postinst=$HOME/.dotfiles.postinst
+
+# Attempts to safely install the configs as symlinks (backing up existing ones)
+function symlink() {
+    src=$1
+    dest=$2
+
+    if [ -e $dest ]; then
+        if [ -L $dest ]; then
+            # Already symlinked -- I'll assume correctly.
+            return
+        else
+            # Rename files with a ".old" extension.
+            echo "$dest already exists, renaming to $dest.old"
+            backup=$dest.old
+            if [ -e $backup ]; then
+                echo "Error: $backup already exists. Please delete or rename it."
+                exit 1
+            fi
+            mv -v $dest $backup
+        fi
+    fi
+
+    ln -sf $src $dest
+}
 
 echo "Please ensure that the following packages are installed and available in your PATH before proceeding:"
 echo "tmux, vim, zsh, curl, git"
 
 read -p "Press enter to continue. " WAIT_FOR_INPUT
 
-# First things first, install oh-my-zsh
+if ! which git >>/dev/null ; then
+  echo "Error: git is not installed"
+  exit 1
+fi
+
+# If the update script exists, try to do a normal update
+if [ -x "$basedir/check_for_upgrade.sh" ]; then
+    source "$basedir/shell/env"
+    env _DOTFILES=$basedir DISABLE_UPDATE_PROMPT='FALSE' zsh -f $basedir/check_for_upgrade.sh
+else
+    echo "Cloning dotfiles to $basedir"
+    rm -rf $basedir
+    git clone --quiet --depth=1 $repourl $basedir
+fi
+
+# Start installing config
+
 echo "Installing Oh-My-ZSH"
 echo "When the install is done, type `exit` to continue installing dotfiles"
 sh -c "$(curl -fsSL https://raw.github.com/robbyrussell/oh-my-zsh/master/tools/install.sh)"
 
-echo "Overriding ~/.zshrc. A backup can be found at ~/.zshrc.backup"
-mv ~/.zshrc ~/.zshrc.backup
-ln -s ~/dotfiles/shell/zshrc ~/.zshrc
-
-echo "Overriding ~/.bashrc. A backup can be found at ~/.bashrc.backup"
-mv ~/.bashrc ~/.bashrc.backup
-ln -s ~/dotfiles/shell/bashrc ~/.bashrc
-
-echo "Installing tmux config"
-ln -s ~/dotfiles/tmux.conf ~/.tmux.conf
+echo "Creating Symlinks"
+symlink $basedir/shell/zshrc $HOME/.zshrc
+symlink $basedir/shell/bashrc $HOME/.bashrc
+symlink $basedir/tmux.conf $HOME/.tmux.conf
+symlink $basedir/vimrc $HOME/.vimrc
+symlink $basedir/gitconfig $HOME/.gitconfig
 
 echo "Installing VIM Pathogen"
-mkdir -p ~/.vim/autoload ~/.vim/bundle
-curl -LSso ~/.vim/autoload/pathogen.vim https://tpo.pe/pathogen.vim
+mkdir -p $HOME/.vim/autoload $HOME/.vim/bundle
+curl -LSso $HOME/.vim/autoload/pathogen.vim https://tpo.pe/pathogen.vim
 
 echo "Installing VIM Sensible"
-cd ~/.vim/bundle
+cd $HOME/.vim/bundle
 git clone git://github.com/tpope/vim-sensible.git
 
-echo "Installing VIM config"
-ln -s ~/dotfiles/vimrc ~/.vimrc
-
-echo "Installing (user) global git config"
-ln -s ~/dotfiles/gitconfig ~/.gitconfig
+echo "Adding user bin"
+mkdir -p $bindir $basedir/.bin
+for path in bin/* ; do
+    symlink $basedir/$path $bindir/$(basename $path)
+done
 
 echo "Changing default shell to ZSH"
 chsh -s /usr/bin/zsh
 
-# Make the install directories
-echo "Making install directories"
-mkdir -p ~/bin ~/dotfiles/.bin
-
-# Install wp-cli
-# echo "Installing wp-cli"
-# cd ~/dotfiles/.bin
-# curl -O https://raw.githubusercontent.com/wp-cli/builds/gh-pages/phar/wp-cli.phar
-# chmod a+x wp-cli.phar
-# ln -s ~/dotfiles/.bin/wp-cli.phar ~/bin/wp
-
-# Since $HOME/bin is in the PATH, this should work
-# wp --info
+if [ -e "$postinst" ]; then
+    echo "Running post install"
+    source "$postinst"
+else
+    echo "No post install script found. Optionally create one at $postinst"
+fi
 
 echo "Install done."
 echo "Check tmux, vim, and your shell to verify everything is correct"
 echo "you may need to launch a new instance of your shell"
+
+} # Ensures that the whole script is downloaded before execution