# Injects the firmware version from `git describe` (semver tags like v0.1.0).
import subprocess

Import("env")  # noqa: F821  (provided by PlatformIO)

try:
    version = subprocess.check_output(
        ["git", "describe", "--tags", "--always", "--dirty"], text=True
    ).strip()
except Exception:
    version = "unknown"

# The version goes into one generated header, read by one file (lib/version/src/version.cpp). As a -D
# on every command line it made each new commit recompile everything, and no build cache could help
# (issue #74). Written only when it changes, so an unchanged version rebuilds nothing.
import os

_header = os.path.join(env.subst("$PROJECT_DIR"), "lib", "version", "src", "version_generated.h")  # noqa: F821
_text = '#define RORO_VERSION "%s"\n' % version
if not os.path.exists(_header) or open(_header).read() != _text:
    open(_header, "w").write(_text)


# Keep every build's ELF, named by version and the first 16 hex digits of its SHA-256 (the core dump
# names the crashed firmware by the same digest), so a crash can be decoded after later builds.
def archive_elf(source, target, env):
    import hashlib
    import os
    import shutil

    elf = str(target[0])
    digest = hashlib.sha256(open(elf, "rb").read()).hexdigest()[:16]
    folder = os.path.join(env.subst("$PROJECT_DIR"), ".pio", "elves")
    os.makedirs(folder, exist_ok=True)
    shutil.copy(elf, os.path.join(folder, "%s.%s.elf" % (version, digest)))


env.AddPostAction("$BUILD_DIR/${PROGNAME}.elf", archive_elf)  # noqa: F821