#!/bin/bash
#------------------------------------------------------------------------------
# =========                 |
# \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
#  \\    /   O peration     |
#   \\  /    A nd           | www.openfoam.com
#    \\/     M anipulation  |
#-------------------------------------------------------------------------------
#     Copyright (C) 2016 OpenFOAM Foundation
#------------------------------------------------------------------------------
# License
#     This file is part of OpenFOAM, distributed under GPL-3.0-or-later.
#
# Script
#     wmakeCollect
#
# Usage
#     wmakeCollect [OPTION] <command>
#
# Description
#     wmake scheduler for efficient parallel compilations.
#
#-------------------------------------------------------------------------------
Script=${0##*/}

usage() {
    exec 1>&2
    while [ "$#" -ge 1 ]; do echo "$1"; shift; done
    cat<<USAGE

Usage: $Script [OPTION] <command>

options:
  -clean        Cleanup before compilation (removes old makefiles)
  -kill         Cleanup after termination (removes makefiles)
  -h | -help    Print the usage

A collecting scheduler for fast parallel compilation of large numbers of
object files.

When called with a compilation command it is written into a file in the
directory \$WM_COLLECT_DIR.

When called without a command the files in the \$WM_COLLECT_DIR directory are
combined into a single Makefile which is passed to make to compile all of the
object files efficiently in parallel.

Typical usage for compiling OpenFOAM:

  - Ensure all lnInclude directories are up-to-date:
    wmakeLnIncludeAll

  - Compile all with this scheduler:
    wmake -queue

USAGE
    exit 1
}

# Set true to clean-up file if interrupted
unset cleanup

while [ "$#" -gt 0 ]
do
    case "$1" in
    ('') ;;
    (- | --) shift; break ;;  # Stop option parsing

    -h | -help*)
        usage
        ;;
    -clean | -kill)
        cleanup=true
        ;;
    -*)
        usage "unknown option: '$*'"
        ;;
    *)
        break
        ;;
    esac
    shift
done


if [ -z "$WM_COLLECT_DIR" ]
then
    echo "$Script error: WM_COLLECT_DIR not set" 1>&2
    exit 1
fi


if [ -n "$WM_QUIET" ]
then
    E="@"
fi


# Collected makefile for this build
makefile="$WM_COLLECT_DIR.Makefile"


# Clean-up files and exit
if [ "$cleanup" = true ]
then
    rm -rf "$WM_COLLECT_DIR"
    rm -f "$makefile"
    exit 0
fi


if [ "$#" -gt 0 ]
then
    # Make sure directories exist
    mkdir -p "$WM_COLLECT_DIR"

    # The current source file
    sourceFile="${@: -3:1}"

    # The current target
    objectFile="${@: -1:1}"

    # Create a unique name for the makefile from the object path
    file="$(mktemp $WM_COLLECT_DIR/XXXXXX)"

    # Add the current target to the list of objects
    echo "OBJECTS += $objectFile" >> $file

    # Add the build rule for the current target
    echo "$objectFile: $makefile" >> $file
    [ -z "$E" ] ||
        echo -e "\t@echo \"    compiling: ${sourceFile##*/}\"" >> $file
    echo -e "\t$E cd $PWD && \\" >> $file
    echo -e "\t${@:1:($#-1)} $objectFile" >> $file
    echo >> $file
elif [ -d "$WM_COLLECT_DIR" ]
then
    # Collect all the makefiles into a single makefiles for this build
    (cd $WM_COLLECT_DIR && ls -1rt | xargs cat > $makefile)

    # Add a build rule for all of the targets
    echo 'all: $(OBJECTS)' >> $makefile

    # Clear out all of the target makefiles
    rm -rf "$WM_COLLECT_DIR"

    # Run make on the collected makefile
    make -j $WM_NCOMPPROCS -f $makefile all

    rm -f "$makefile"
fi

exit 0 # clean exit

#------------------------------------------------------------------------------