# ------------------------------------------------------------------------------
# Add native rules to configure source files
def gflags_sources(namespace=["google", "gflags"]):
    native.genrule(
        name = "config_h",
        srcs = ["src/config.h.in"],
        outs = ["config.h"],
        cmd  = "awk '{ gsub(/^#cmakedefine/, \"//cmakedefine\"); print; }' $(<) > $(@)"
    )
    native.genrule(
        name = "gflags_declare_h",
        srcs = ["src/gflags_declare.h.in"],
        outs = ["gflags/gflags_declare.h"],
        cmd  = ("awk '{ " +
                "gsub(/@GFLAGS_NAMESPACE@/, \"" + namespace[0] + "\"); " +
                "gsub(/@(HAVE_STDINT_H|HAVE_SYS_TYPES_H|HAVE_INTTYPES_H|GFLAGS_INTTYPES_FORMAT_C99)@/, \"1\"); " +
                "gsub(/@([A-Z0-9_]+)@/, \"0\"); " +
                "print; }' $(<) > $(@)")
    )
    gflags_ns_h_files = []
    for ns in namespace[1:]:
        gflags_ns_h_file = "gflags_{}.h".format(ns)
        native.genrule(
            name = gflags_ns_h_file.replace('.', '_'),
            srcs = ["src/gflags_ns.h.in"],
            outs = ["gflags/" + gflags_ns_h_file],
            cmd  = ("awk '{ " +
                    "gsub(/@ns@/, \"" + ns + "\"); " +
                    "gsub(/@NS@/, \"" + ns.upper() + "\"); " +
                    "print; }' $(<) > $(@)")
        )
        gflags_ns_h_files.append(gflags_ns_h_file)
    native.genrule(
        name = "gflags_h",
        srcs = ["src/gflags.h.in"],
        outs = ["gflags/gflags.h"],
        cmd  = ("awk '{ " +
                "gsub(/@GFLAGS_ATTRIBUTE_UNUSED@/, \"\"); " +
                "gsub(/@INCLUDE_GFLAGS_NS_H@/, \"" + '\n'.join(["#include \\\"gflags/{}\\\"".format(hdr) for hdr in gflags_ns_h_files]) + "\"); " +
                "print; }' $(<) > $(@)")
    )
    native.genrule(
        name = "gflags_completions_h",
        srcs = ["src/gflags_completions.h.in"],
        outs = ["gflags/gflags_completions.h"],
        cmd  = "awk '{ gsub(/@GFLAGS_NAMESPACE@/, \"" + namespace[0] + "\"); print; }' $(<) > $(@)"
    )
    hdrs = [":gflags_h", ":gflags_declare_h", ":gflags_completions_h"]
    hdrs.extend([':' + hdr.replace('.', '_') for hdr in gflags_ns_h_files])
    srcs = [
        ":config_h",
        "src/gflags.cc",
        "src/gflags_completions.cc",
        "src/gflags_reporting.cc",
        "src/mutex.h",
        "src/util.h"
    ]
    return [hdrs, srcs]

# ------------------------------------------------------------------------------
# Add native rule to build gflags library
def gflags_library(hdrs=[], srcs=[], threads=1):
    name = "gflags"
    copts = [
        "-DHAVE_STDINT_H",
        "-DHAVE_SYS_TYPES_H",
        "-DHAVE_INTTYPES_H",
        "-DHAVE_SYS_STAT_H",
        "-DHAVE_UNISTD_H",
        "-DHAVE_FNMATCH_H",
        "-DHAVE_STRTOLL",
        "-DHAVE_STRTOQ",
        "-DHAVE_PTHREAD",
        "-DHAVE_RWLOCK",
        "-DGFLAGS_INTTYPES_FORMAT_C99",
        "-DGFLAGS_IS_A_DLL=0",
    ]
    linkopts = []
    if threads:
        linkopts.append("-lpthread")
    else:
        name += "_nothreads"
        copts.append("-DNO_THREADS")
    native.cc_library(
        name       = name,
        hdrs       = hdrs,
        srcs       = srcs,
        includes   = ["$(GENDIR)"],
        copts      = copts,
        linkopts   = linkopts,
        visibility = ["//visibility:public"]
    )