# frontend/apiserver — Go REST API server with CGO backend integration.
#
# CGO is required for two reasons:
#   1. pam_linux.go: dlopen/dlsym for PAM (handled by -ldl in the source file)
#   2. backend/clib.go: libxce C client library for IPC with the controller
#
# Include/link flags for libxce and its transitive deps are gathered from
# pkg-config and injected into CGO_CFLAGS/CGO_LDFLAGS so the go_build script
# can substitute path placeholders before invoking go build.

cgo_cflags  = ''
cgo_ldflags = ''

if with_debug
  cgo_cflags  += '-fsanitize=address -g -DWITH_DEBUG=1 '
  cgo_ldflags += '-fsanitize=address -g '
endif

# Deps whose cflags/ldflags must be passed into CGO (transitive libxce deps).
apiserver_cgo_deps = [
  librtti_dep,
  c_capnproto_dep,
  ssl_dep,
  tinylog_dep,
  math_dep,
  rt_dep,
]

foreach dep : apiserver_cgo_deps
  cf = run_command(pkgconfig, '--cflags', dep.name(), check: false)
  if cf.returncode() == 0
    cgo_cflags += ' ' + cf.stdout().strip()
  endif
  lf = run_command(pkgconfig, '--libs', dep.name(), check: false)
  if lf.returncode() == 0
    cgo_ldflags += ' ' + lf.stdout().strip()
  endif
endforeach

# Add the source and build-directory include paths with meson placeholders.
# The go_build script resolves @CURRENT_SOURCE_DIR@ and @BUILD_ROOT@ at build time.
cgo_cflags += ' -I@CURRENT_SOURCE_DIR@/../../include -I@BUILD_ROOT@/lib'
cgo_ldflags += ' -L@BUILD_ROOT@/lib -lxce'

go_env = environment()
go_env.set('CGO_CFLAGS',  cgo_cflags)
go_env.set('CGO_LDFLAGS', cgo_ldflags)
go_env.set('BUILDTYPE',   get_option('buildtype'))
go_env.set('FIX_ENVARS',  'CGO_CFLAGS CGO_LDFLAGS')
go_env.set('ENVARS',      'CURRENT_SOURCE_DIR BUILD_ROOT')
go_env.set('DEPENDENCIES','thread math')

custom_target('apiserver',
  input:   'cmd/main.go',
  output:  'xce_apiserver',
  command: [env_program,
            'CURRENT_SOURCE_DIR="@CURRENT_SOURCE_DIR@"',
            'BUILD_ROOT="@BUILD_ROOT@"',
            'XCE_GIT_COMMIT=' + get_option('commit_id'),
            'XCE_BUILD_TIME=' + get_option('build_time'),
            'XCE_DIRTY_FINGERPRINT=' + get_option('dirty_fingerprint'),
            go_build_program,
            '@INPUT@', '@OUTPUT@'],
  env:     go_env,
  depends: [libxce],
  install: true,
  install_dir: get_option('prefix') / 'bin')

# CGO-backed backend test suite, run directly via `go test` under Meson's
# test runner (not through tools/go_build, which only knows how to invoke
# `go build` once for a single output). This reuses apiserver_cgo_deps's
# already-computed cgo_cflags/cgo_ldflags (the same values the custom_target
# above uses) rather than deriving CGO flags a second time.
#
# cgo_cflags/cgo_ldflags still contain the literal @CURRENT_SOURCE_DIR@/
# @BUILD_ROOT@ placeholder tokens appended above -- normally resolved by
# go_build's own fix_env/fix_input_envs sed machinery at build time. Since
# this target bypasses go_build entirely, resolve those tokens ourselves at
# Meson-configure time via Meson's own string .replace().
resolved_cgo_cflags  = cgo_cflags.replace('@CURRENT_SOURCE_DIR@', meson.current_source_dir()).replace('@BUILD_ROOT@', meson.project_build_root())
resolved_cgo_ldflags = cgo_ldflags.replace('@CURRENT_SOURCE_DIR@', meson.current_source_dir()).replace('@BUILD_ROOT@', meson.project_build_root())

test('apiserver backend', go_compiler,
     args:    ['test', './backend/...', '-count=1'],
     workdir: meson.current_source_dir(),
     env:     {'CGO_ENABLED': '1',
               'CGO_CFLAGS': resolved_cgo_cflags,
               'CGO_LDFLAGS': resolved_cgo_ldflags,
               'GOFLAGS': '-mod=vendor',
               'GOPROXY': 'off',
               'GOCACHE': meson.current_build_dir() / 'go-cache',
               'GOPATH': meson.current_build_dir() / 'go-path'},
     suite:   'apiserver',
     # A cold GOCACHE/GOPATH (the normal case: both are freshly created
     # under this build dir, see above) makes `go test` compile the whole
     # CGO+ASAN dependency graph from scratch -- measured ~34s, already over
     # Meson's 30s test() default. Matches the timeout the existing
     # 'controller test' registration uses for the same reason (see
     # controller/meson.build / steering build-deployment.md).
     timeout: 300,
     depends: [libxce])