/**
 * @file ui.c
 * @brief Unit tests for the UI subsystem: lifecycle, arena sizing and validation.
 *
 * Everything here runs without a window, a renderer, or SDL_Init at all --
 * akgl_ui_init takes its layout dimensions as parameters precisely so that a
 * test can bring the subsystem up headless. Only akgl_error_init() is needed
 * first, so that AKGL_ERR_UI carries its name into any trace these tests
 * produce.
 */

#include <akerror.h>

#include <akgl/error.h>
#include <akgl/ui.h>

#include "testutil.h"

/**
 * @brief Init must refuse bad dimensions and an uninitialized resize.
 *
 * Runs before anything initializes the subsystem, because the "not
 * initialized" refusal is half of what it asserts.
 */
akerr_ErrorContext *test_ui_validation(void)
{
    PREPARE_ERROR(e);

    ATTEMPT {
	TEST_EXPECT_STATUS(e, AKERR_OUTOFBOUNDS, akgl_ui_init(0, 240),
			   "akgl_ui_init accepted a zero width");
	TEST_EXPECT_STATUS(e, AKERR_OUTOFBOUNDS, akgl_ui_init(320, -1),
			   "akgl_ui_init accepted a negative height");
	TEST_EXPECT_STATUS(e, AKGL_ERR_UI, akgl_ui_resize(320, 240),
			   "akgl_ui_resize worked on an uninitialized subsystem");
    } CLEANUP {
    } PROCESS(e) {
    } FINISH(e, true);
    SUCCEED_RETURN(e);
}

/**
 * @brief Init, double-init refusal, idempotent shutdown, re-init.
 *
 * The double init has to be refused rather than absorbed: a second
 * Clay_Initialize over a live context would silently discard every element id
 * and scroll position the first one held, which is the kind of reset a game
 * only notices as "the menu forgot where it was".
 */
akerr_ErrorContext *test_ui_lifecycle(void)
{
    PREPARE_ERROR(e);

    ATTEMPT {
	TEST_EXPECT_OK(e, akgl_ui_init(320, 240), "first akgl_ui_init failed");
	TEST_EXPECT_STATUS(e, AKGL_ERR_UI, akgl_ui_init(320, 240),
			   "a second akgl_ui_init was not refused");
	TEST_EXPECT_OK(e, akgl_ui_resize(640, 480), "resize on a live subsystem failed");
	TEST_EXPECT_OK(e, akgl_ui_shutdown(), "akgl_ui_shutdown failed");
	TEST_EXPECT_OK(e, akgl_ui_shutdown(), "a second akgl_ui_shutdown was not a no-op");
	TEST_EXPECT_OK(e, akgl_ui_init(320, 240), "re-init after shutdown failed");
	TEST_EXPECT_OK(e, akgl_ui_shutdown(), "shutdown after re-init failed");
    } CLEANUP {
	IGNORE(akgl_ui_shutdown());
    } PROCESS(e) {
    } FINISH(e, true);
    SUCCEED_RETURN(e);
}

/**
 * @brief A too-small arena must refuse at init, loudly, and recover.
 *
 * The narrowed limit stands in for a consumer who raised AKGL_UI_MAX_ELEMENTS
 * without raising AKGL_UI_ARENA_BYTES: the refusal at startup, with both
 * numbers in the message, is the whole safety story -- past init, clay trusts
 * the arena completely. Same shape as the collision arena's exhaustion test,
 * for the same reason: rebuilding with a smaller ceiling is not something CI
 * can do.
 */
akerr_ErrorContext *test_ui_arena_exhaustion(void)
{
    PREPARE_ERROR(e);

    ATTEMPT {
	akgl_ui_arena_limit(64);
	TEST_EXPECT_STATUS(e, AKGL_ERR_UI, akgl_ui_init(320, 240),
			   "akgl_ui_init accepted an arena clay cannot fit in");
	akgl_ui_arena_limit(0);
	TEST_EXPECT_OK(e, akgl_ui_init(320, 240),
		       "akgl_ui_init failed after the arena limit was restored");
	TEST_EXPECT_OK(e, akgl_ui_shutdown(), "shutdown after the exhaustion test failed");
    } CLEANUP {
	akgl_ui_arena_limit(0);
	IGNORE(akgl_ui_shutdown());
    } PROCESS(e) {
    } FINISH(e, true);
    SUCCEED_RETURN(e);
}

int main(void)
{
    PREPARE_ERROR(errctx);

    ATTEMPT {
	CATCH(errctx, akgl_error_init());
	CATCH(errctx, test_ui_validation());
	CATCH(errctx, test_ui_lifecycle());
	CATCH(errctx, test_ui_arena_exhaustion());
    } CLEANUP {
    } PROCESS(errctx) {
    } FINISH_NORETURN(errctx);
}