#!/bin/bash

set -e

#### Config

NODE_DOWNLOAD='http://nodejs.org/dist/v0.6.10/node-v0.6.10.tar.gz'
NPM_DOWNLOAD='http://npmjs.org/install.sh'
VIRTUALENV_DOWNLOAD='http://github.com/pypa/virtualenv/raw/develop/virtualenv.py'
MONGODB_DOWNLOAD='http://fastdl.mongodb.org/OS/mongodb-OS-ARCH-2.0.0.tgz'

#### Helper functions

# check_for name exec_name version_command [minimum_version]
check_for() {
    name="$1"
    command="$2"
    get_version="$3"
    min_version="$4"
    max_version="$5"

    if which $command >/dev/null 2>&1; then
        # It's installed
        version=$($get_version 2>/dev/null | grep -o -E [-0-9.]\{1,\} | head -n 1)
        if [ -n "$version" ]; then
            echo "$name version $version found."

            if [ -n "$min_version" ]; then
                if ! perl -e 'exit 1 unless v'$version' ge v'$min_version
                then
                    echo "$1 version $version found (>=$min_version required)"
                    return 1
                fi

                if [ -n "$max_version" ]; then
                    if ! perl -e 'exit 1 unless v'$version' lt v'$max_version
                    then
                        echo "$1 version $version found (<$max_version required)"
                        return 1
                    fi
                fi
            fi

            return 0
        fi
        # fall through
    fi

    # not found
    min="${min_version:-(none)}"
    max="${max_version:-(none)}"
    echo "$name not found (want version >= $min and < $max)"
    return 1
}

# check_for_pkg_config name pkg_config_name [minimum_version [optional]]
check_for_pkg_config() {
    name="$1"
    pkg_config_name="$2"
    min_version="$3"

    if ! which pkg-config >/dev/null 2>&1; then
        echo "pkg-config is not installed: assuming $name is not present either"
        return 1
    fi

    if ! pkg-config --exists "$pkg_config_name"
    then
        echo "$name not found!" >&2
        return 1
    fi
    version="$(pkg-config --modversion "$pkg_config_name")"
    echo "${name} version ${version} found."

    [ -z "$min_version" ] && return 0
    if pkg-config --atleast-version="$min_version" "$pkg_config_name"
    then
        return 0
    else
        echo "$name version $min_version or greater required!" >&2
        return 1
    fi
}

download () {
    base="$(basename $1)"
    if [ -f ${base} ]
    then
        echo "$1 already downloaded."
    else
        if wget "$1" 2>/dev/null || curl -L -o ${base} "$1"
        then
            echo "Downloaded $1."
        else
            echo "Download of $1 failed!" >&2
            exit 1
        fi
    fi
}

#### Main script

if [ "$1" = "--check-only" ]; then
    check_only=true
else
    prefix="$1"
    if [ ! -n "$prefix" ]; then
        echo "Usage: install-dependencies <install prefix>"
    fi
    mkdir -p "${prefix}"
    # canonicalize (MacOS doesn't have readlink -f)
    prefix=$(cd "$prefix"; pwd)

    envscript="${prefix}/environment.sh"
    cat > "${envscript}" <<MRBARGLES
export PATH="${prefix}/local/bin":${PATH}
export NODE_PATH="${prefix}/local/lib/node_modules":${NODE_PATH}
export PKG_CONFIG_PATH="${prefix}/local/lib/pkgconfig":${PKG_CONFIG_PATH}
export CXXFLAGS="-I${prefix}/local/include"
export LD_LIBRARY_PATH="${prefix}/local/lib"
export LIBRARY_PATH="${prefix}/local/lib"
MRBARGLES

    . "${envscript}"

    mkdir -p ${prefix}/build
    cd ${prefix}/build
fi

check_for Git git 'git --version'
#check_for Python python 'python -V' 2.6

if ! check_for Node.js node 'node -v' 0.6.0 0.7.0
then
    if [ "$check_only" = true ]; then exit 1; fi

    echo ""
    echo "You don't seem to have node.js installed."
    echo "I will download, build, and install it locally."
    echo "This could take quite some time!"
    download "${NODE_DOWNLOAD}"
    tar zxf "$(basename "${NODE_DOWNLOAD}")"

    cd $(basename "${NODE_DOWNLOAD}" .tar.gz)
    ./configure --prefix="${prefix}/local"
    make
    make install

    echo "Installed node.js into ${prefix}"
fi

if ! check_for npm npm "npm -v" 1
then
    if [ "$check_only" = true ]; then exit 1; fi

    echo ""
    echo "About to download and install locally npm."
    cd "${prefix}/build"
    download "${NPM_DOWNLOAD}"
    if cat "$(basename ${NPM_DOWNLOAD})" | clean=no sh
    then
        echo "Installed npm into ${prefix}"
    else
        echo "Failed to install npm into ${prefix}" >&2
        exit 1
    fi
fi

if ! check_for mongoDB mongod "mongod --version" 1.8.0
then
    if [ "$check_only" = true ]; then exit 1; fi

    OS=`uname -s`
    case "${OS}" in
        Linux)
            OS=linux
            ;;
        Darwin)
            OS=osx
            ;;
        *)
            echo "Don't recognize OS ${OS}" >&2
            exit 1
    esac
    BITS=`getconf LONG_BIT`
    ARCH='x86_64'
    if [ "${BITS}" -ne 64 ]
    then
        ARCH="i386"
        if [ "${OS}" != "osx" ]
        then
            ARCH="i686"
        fi
    fi
    echo ""
    echo "Downloading and installing locally mongoDB"
    MONGODB_DOWNLOAD=$(echo ${MONGODB_DOWNLOAD} | sed -e "s/OS/${OS}/g" -e "s/ARCH/${ARCH}/g")
    download "${MONGODB_DOWNLOAD}"
    mkdir "${prefix}/local" "${prefix}/local/bin"
    if tar zxf $(basename "${MONGODB_DOWNLOAD}") &&
        cp $(basename "${MONGODB_DOWNLOAD}" .tgz)/bin/* "${prefix}/local/bin"
    then
        echo "Installed local mongoDB."
    else
        echo "Failed to install local mongoDB." >&2
        exit 1
    fi
fi

#if ! check_for ImageMagick convert "convert --version" 6.0
#then
#    if [ "$check_only" = true ]; then exit 1; fi

#    echo "You need ImageMagick, but this script doesn't know how to install it for you." >&2
#    echo "Please install it and try again."
#    exit 1
#fi

if [ "$check_only" != true ]; then
    rm -rf "${prefix}/build"
fi