#!/bin/sh -e

# Configuration
dir_build="$PWD/build"  # Temporary directory to build packages
dir_source="$PWD/source"  # Directory where the package sources will be placed
dir_install="$PWD/install"  # Directory where the package will be installed
dir_sysroot=""  # The root dir (The directory programs will look in and symlinks will point to)
dir_prefix="/usr"  # Prefix directory
cmd_download="curl -# -L -o {dst} {src}"  # Command to execute to download files
cmd_extract="tar -x -C {dst} -f {src}"  # Command to execute to extract files
unset dir_satellites  # Directory where the satellite files are placed.
unset options
[ -f /etc/astronaut.conf ] && . /etc/astronaut.conf
[ -f "$HOME/.astronaut.conf" ] && . "$HOME/.astronaut.conf"

# Options not in the configuration
_download_only=false
_vcs_only=false
vcs_compile=false
#_nuke_dir_install (This can be set from wrappers)

# Some printing functions
_show_help() {
echo "This astronaut will help you build some satellites.
Just describe what he's got to do in a satellite file.
Usage: $0 [-sbipr <dir>] [-Id] [-o <options>] <satellite>

-h/? Show this message
-b   Set build directory [WARNING: Will be deleted before build]
-s   Set source directory
-i   Set install directory
-p   Set prefix directory
-r   Set root directory
-I   Nuke install directory before build
-d   Only download package files
-v   Only build vcs package if any updates have been made to it
-o   Set package options (comma-separated)"
}

_msg() {
    echo "=> $@"
}

_exiterr() {
    echo "===> Houston, we've got a problem: $@" 1>&2
    exit 1
}

# Gather info
while getopts "h?s:b:i:p:r:IcCdvo:" opt; do
    case "$opt" in
        h|\?)
            _show_help
            exit 0
            ;;
        s)
            dir_source="$OPTARG"
            ;;
        b)
            dir_build="$OPTARG"
            ;;
        i)
            dir_install="$OPTARG"
            ;;
        p)
            dir_prefix="$OPTARG"
            ;;
        r)
            dir_sysroot="$OPTARG"
            ;;
        I)
            _nuke_dir_install=true
            ;;
        d)
            _download_only=true
            ;;
        v)
            _vcs_only=true
            ;;
        o)
            options="$options "$(printf "$OPTARG" | sed -e 's/,/ /g')""
            ;;
    esac
done

shift $((OPTIND-1))
[ "$1" = "--" ] && shift

if [ ! "$1" ]; then
    _show_help
    exit 1
fi

# Tools for the astronaut
_mksum() {
    echo "$(md5sum "$@" 2> /dev/null | cut -d' ' -f1)"
}

download() {
    mkdir -p "$dir_source/$name"

    local filename="$(basename "$1" | cut -d? -f1)"
    local path="$dir_source/$name/$filename"

    [ "$2" -a -f "$path" ] && local checksum="$(_mksum "$path")"

    if [ ! -e "$path" -o "$checksum" != "$2" ]; then
        _msg "Downloading $filename"

        [ "$3" ] && local cmd="$3" || local cmd="$cmd_download"
        eval $(echo "$cmd" | sed -e "s@{dst}@'$path'@g" -e "s@{src}@'$1'@g")

        checksum="$(_mksum "$path")"
        if [ "$2" -a "$checksum" != "$2" ]; then
            _msg "Checksum: $checksum"
            _exiterr "Checksum failed"
        fi
    fi
}

extract() {
    _msg "Extracting $1"
    [ "$2" ] && local dest="$2" || local dest="."
    [ "$3" ] && local cmd="$3" || local cmd="$cmd_extract"
    eval $(echo "$cmd" | sed -e "s@{src}@'$dir_source/$name/$1'@g" -e "s@{dst}@'$dest'@g")
}

getfile() {
    cp -r "$dir_source/$name/$1" "$dir_build/$1"
}

extrafile() {
    cp "$(dirname "$_satellite")/extrafiles/$_satname/$1" "$dir_build/$1"
}

dlextract() {
    download "$1" "$2"
    extract "$(basename "$1" | cut -d? -f1)"
}

dlfile() {
    download "$1" "$2"
    getfile "$(basename "$1" | cut -d? -f1)"
}

option() {
    local check=$1
    shift

    local negate=false
    case "$check" in
        !*)
            local negate=true
            local check="$(printf "$check" | cut -c 2-)"
            ;;
    esac

    local enabled=false
    local option
    for option in $options; do
        if [ "$option" = "$check" ]; then
            local enabled=true
            break
        fi
    done

    if [ "$negate" = true ]; then
        # Shitty way to do a simple "NOT" operation (come on, it's just one operation on most cpus).
        [ "$enabled" = true ] && local enabled=false || local enabled=true
    fi

    if [ "$1" ]; then
        [ "$enabled" = true ] && eval $@ || true
    else
        return $([ "$enabled" = true ])
    fi
}

import() {
    . "$(dirname "$_satellite")/functions/$1.sh"
}

# Set some functions in accordance to the _download_only option.
header_end() { :; }
if [ "$_vcs_only" = true ]; then
    header_end() {
        if [ ! "$vcs_compile" = true ]; then
            exit
        fi
    }
fi
if [ "$_download_only" = true ]; then
    # Disable some functions
    extract() { :; }
    getfile() { :; }
    extrafile() { :; }

    # Exit at the end of the header
    header_end() { exit; }
fi

_satellite="$(realpath "$1")"
_satname="$(basename "$_satellite" .sat)"

# Try to find the satellite file if it can't be found.
if [ ! -f "$_satellite" ]; then
    if [ -d "$dir_satellites" ]; then
        file="$(find "$dir_satellites" -type f \( -name "$_satname.sat" -o -name "$_satname" \) -print -quit)"
        if [ -f "$file" ]; then
            _satellite="$(realpath "$file")"
            _satname="$(basename "$_satellite" .sat)"
        fi
    fi

    # If it still can't be found, exit.
    if [ ! -f "$_satellite" ]; then
        _exiterr "Can't find satellite"
    fi
fi

# Create the directories
if [ "$_download_only" = false ]; then
    # This variable can be set by a wrapper script in need to nuke the install dir.
    if [ "$_nuke_dir_install" = true ]; then
        rm -rf "$dir_install"
    fi

    rm -rf "$dir_build"
    mkdir -p "$dir_build"
    mkdir -p "$dir_install"
    cd "$dir_build"
fi

# Create the satellite
. "$_satellite"