#!/bin/bash
#
# develop_brew_cask
#

set -e;               # exit on any uncaught error
set +o histexpand;    # don't expand history expressions
shopt -s nocasematch; # case-insensitive regular expressions

cd_to_project_root () {
    local script_dir="$(/usr/bin/dirname $0)"
    cd "$script_dir"
    local git_root="$(git rev-parse --show-toplevel)"
    if [[ -z "$git_root" ]]; then
        printf "Could not find git project root"
        exit 1;
    fi
    cd "$git_root"
}

cd_to_version_dir () {
    local cellar_dir="$1"
    local version_dir="$2"
    if [ -z "$version_dir" ]; then
        printf "Can't get version dir under $cellar_dir/\n";
        exit 1;
    fi
    cd "$cellar_dir/$version_dir"
}

create_dev_links () {
    local git_root="$1"
    local tap_dir="$2"
    mv rubylib production_rubylib
    mv Casks   production_Casks
    ln -s "$git_root/Casks" .
    ln -s "$git_root/lib"   rubylib
    cd "$tap_dir"
    mv lib   production_lib
    mv Casks production_Casks
    ln -s "$git_root/Casks" .
    ln -s "$git_root/lib"   .
}

_develop_brew_cask () {

    # configurable
    local tap_subdir="Library/Taps/phinze-cask"

    # initialization
    cd_to_project_root;
    local git_root=`pwd`
    local brew_prefix="$(brew --prefix)"
    local cellar_dir="$brew_prefix/Cellar/brew-cask"
    local version_dir=$(/bin/ls "$cellar_dir/" | sort | tail -1)
    local tap_dir="$brew_prefix/$tap_subdir"

    # sanity check
    if [[ $(/usr/bin/stat -L -f '%i' "$tap_dir") -eq $(/usr/bin/stat -L -f '%i' "$git_root") ]]; then
        printf "\nERROR: run this script in your private repo, not inside Homebrew.\n";
        exit 1;
    fi

    # action
    cd_to_version_dir "$cellar_dir" "$version_dir";
    if [ -e "production_rubylib" ]; then
        printf "brew-cask is already set up for development\n";
        exit 1
    else
        create_dev_links "$git_root" "$tap_dir";
        printf "brew-cask is now in development mode\n"
        printf "Note: it is not safe to run 'brew update' while in development mode\n"
    fi

}

if [[ $1 =~ ^-+h(elp)?$ ]]; then
    printf "develop_brew_cask

Symlink private repo directories into Homebrew's Cellar, so
that the 'brew cask' command will use the current development
branch in your private repo.

Saves the production Homebrew directories under new names.

You can reverse this operation with 'production_brew_cask'.

Note: it is not safe to run 'brew update' while development
mode is in effect.

"
    exit
fi

_develop_brew_cask "$@";

#