#!/bin/bash

. "$MKIT_DIR/include/ini.sh" || die "cannot import ini.sh"


build() {
    #
    # Add meat to all skeletons
    #
    local srcpath
    find src -type f -name '*.skel' \
     | while read srcpath;
       do
           build1 "$srcpath"
       done
}

build1() {
    #
    # Process one skeleton
    #
    local srcpath dstpath
    srcpath=$1
    dstpath=${srcpath%.skel}
    case $dstpath in
        *.md) <"$srcpath" expand_includes | expand_variables >"$dstpath" ;;
        *)    <"$srcpath"                   expand_variables >"$dstpath" ;;
    esac
    echo "$dstpath" >> built.list
}

build_manpages() {
    local manfile mdfile
    if command -v ronn >/dev/null;
    then
        ini lskeys "files:man" \
          | while read manfile;
            do
                mdfile="$manfile.md"
                ronn -r "$mdfile"
                echo "$manfile" >> built.list
            done
    else
        echo "ronn is not installed"
        return 1
    fi
}

clean() {
    #
    # Clean up tree after building
    #
    test -f built.list && {
        <built.list xargs rm -f
        rm -f built.list
    }
    true
}

dist() {
    #
    # Create distributable tarball
    #
    local version=$(get_version)
    local dirname=$MKIT_PKGNAME-$version
    mkdir -p "$dirname"
    local item
    cp -R "$(ini values "lists:dist")" "$dirname"
    sed -i -e "s/^VERSION = .*/VERSION = $version/" "$dirname/config.mk"
    tar -cf "$dirname.tar" "$dirname"
    gzip "$dirname.tar"
    rm -rf "$dirname"
}

expand_includes() {
    #
    # Expand include directives
    #
    # Expand e.g. `<!-- include4: foo.sh -->` to include code of foo.sh
    #
    perl -we '
        use strict;
        my $text;
        while (<>) {
            chomp;
            if (m/<!-- include4: (\S+) -->/) {
                open my $fh, $1 or warn "cannot find: $1";
                my $text = do { local($/); <$fh> };
                close $fh;
                $text =~ s/^(.)/    $1/gm;
                chomp $text;
                print "$text\n";
            } else {
                print "$_\n";
            }
        }
    '
}

expand_variables() {
    #
    # Expand variable values
    #
    local script=$(mktemp --tmpdir mkit-tmp.XXXXXXXXXX)
    local varname varvalue
    ini lskeys "vars" \
      | while read varname;
        do
            varvalue="$(ini 1value "vars:$varname" | sed -e 's/\$/\\$/' )"
            echo "s|$varname|$varvalue|;" >> "$script"
        done
    echo "s|__CODENAME__|$CODENAME|;"     >> "$script"
    echo "s|__VERSION__|$(get_version)|;" >> "$script"
    perl -wp "$script"
    rm "$script"
}

get_version() {
    #
    # Build semver version string with build metadata
    #
    # Build version string from available info using following
    # logic:
    #
    #  1. use VERSION (from config.mk)
    #  2. if we are in git, override the version with last tag
    #  3. if set, add PRERELEASE (from config.mk) as pre-release ID
    #     (afer dash)
    #  4. if we are at a later commit than the last tag, add branch
    #     name and commit sha1 to build metadata (after plus sign)
    #  5. if the tree is "dirty", i.e. has uncommited changes,
    #     add "dirty" to build metadata
    #
    # The version is compatible with SemVer 2.0.0.
    #
    # Examples:
    #
    #     myprog v1.0.7                         # all clear
    #     myprog v1.0.7-alpha                   # PRERELEASE="alpha"
    #     myprog v1.0.7-alpha+g1aef811.master   # ^^ + some commits after
    #     myprog v1.0.7-alpha+gf14fc4f.api2     # ^^ + on a feature branch
    #     myprog v1.0.7-alpha+gf14fc4f.api2.dirty  # ^^ + tree edited
    #     myprog v1.0.7-alpha+dirty             # tag OK but tree edited
    #     myprog v1.0.7+dirty                   # ^^ but no pre-release id
    #
    # Note that versions with "dirty" should be perceived as kind of
    # dangerous outside developer's own machine.  Versions with sha1 are
    # safer but must not be released.
    #
    # I have considered decorating the git commit refs to make them
    # sort of sortable (e.g. "r1.g1aef811"), but on second thought,
    # I don't think it's good idea to give *any* semantics to meta-data
    # at all.  First, there is no rule that r1<r2<r3; a commit can be
    # removing what other just added and one change can be split to
    # multiple commits.  Also, the whole thing breaks anyway once you
    # rebase your branch (no, it's not a sin).  The sole purpose of
    # meta-data is to *identify* the code, and provide safe path back
    # to tree; commit refs are already perfect for that.
    #
    # FIXME:  Using PRERELEASE for release IDs may not be compatible with
    #         release strategy implemented in release.sh
    #
    local version=$VERSION
    local prerl=$PRERELEASE
    grep ":" <<<"$prerl" && warn "colon in PRERELEASE may corrupt version data: $prerl"
    if git rev-parse HEAD >&/dev/null;
    then    # we are in git repo... so we can get smart
        local lasttag=$(git tag | grep ^v | sort -V | tail -n1)
        if ! git describe --tags --exact-match HEAD >&/dev/null;
        then    # we are at a later commit than the last tag
            local sha=g$(git log -1 --pretty=format:%h HEAD)
            local curbranch=$(git rev-parse --abbrev-ref HEAD)
            local commit="$curbranch.$sha"
        fi
        if test "$(git diff --shortstat 2>/dev/null)" != "";
        then    # the tree is "dirty", i.e. has been edited
            local dirty=dirty
        fi
        test -n "$lasttag" && version=${lasttag:1}
        local suffix=""
        case "$commit:$dirty" in
            :)       suffix=""                ;;
            :dirty)  suffix="+$dirty"         ;;
            *:)      suffix="+$commit"        ;;
            *:dirty) suffix="+$commit.$dirty" ;;
        esac
        test -b "$prerl" && suffix="-$prerl$suffix"
        version="$version$suffix"
    fi
    echo "$version"
}