#!/bin/bash

bin="snag"
libs="libcurl libcrypto"
builddir="build"
PREFIX="/usr"

while [ "$1" ]; do
	case "$1" in
		-*) exit 1 ;;
	esac
	shift
done

CFLAGS=${CFLAGS:-""}

CFLAGS_RELEASE="$CFLAGS -O2"
CFLAGS_DEBUG="$CFLAGS -Wall -g -DDEBUG=1"

write() { echo "$@" >> build.ninja; }

echo "$CFLAGS_DEBUG $(pkg-config --cflags $libs)" | tr ' ' '\n' > compile_flags.txt
rm -f build.ninja

write "builddir = $builddir"
write "libs = $(pkg-config --libs $libs)"

write 'rule link'
write '  description = LD $out'
write '  command = gcc $libs $in -o $out'
for target in $(echo "debug release"); do
    eval write "cflags_$target = \$CFLAGS_${target^^} $(pkg-config --cflags $libs)"

    write "rule cc-$target"
    write '  deps = gcc'
    write '  depfile = $out.d'
    write '  description = CC $out'
    write "  command = gcc -MD -MF \$out.d \$cflags_$target -c \$in -o \$out"

    files="$(find . -name '*.c')"
    sedstr=$(printf 's,^\./\(.*\)\.c$,%s\/%s\/\\1.o,g' ${builddir} ${target})
    ofiles=$(echo "$files" | sed ${sedstr})

    for f in $files; do
        of=$(echo $f | sed ${sedstr})
        write "build $of: cc-$target $f"
    done
    write "build $builddir/$target/$bin: link $(echo $ofiles)"
    write "build $target: phony $builddir/$target/$bin"
done

write "default release"

echo "Wrote ./build.ninja file"