/**
 * Copyright (c) 2026 Dominic Masters
 *
 * This software is released under the MIT License.
 * https://opensource.org/licenses/MIT
 */

#include "dusktest.h"
#include "save/slot/saveslot.h"
#include "save/save.h"
#include "save/savejson.h"
#include "util/memory.h"
#include "util/string.h"
#include <stdlib.h>
#include <string.h>

// ============================================================
// Helpers - wrap the writeInit/readInit macros (which can only be used
// inside a function returning errorret_t) so tests can call them plainly.
// ============================================================

static errorret_t slotToJSON(
  saveslot_t *slot, char_t **outJson, size_t *outLen
) {
  writeInit();

  errorret_t writeResult = saveSlotWriteJSON(slot, doc, object);
  if(errorIsNotOk(writeResult)) {
    yyjson_mut_doc_free(doc);
    errorChain(writeResult);
  }

  *outJson = yyjson_mut_write(doc, 0, outLen);
  yyjson_mut_doc_free(doc);
  assertNotNull(*outJson, "Failed to write slot JSON");

  errorOk();
}

static errorret_t slotFromJSON(saveslot_t *slot, const char_t *json) {
  readInit(json, strlen(json));
  errorret_t readResult = saveSlotReadJSON(slot, object);
  yyjson_doc_free(jsonDoc);
  errorChain(readResult);
  errorOk();
}

// ============================================================
// saveSlotInit - only ever operates on SAVE.slot now.
// ============================================================

static void test_saveSlotInit_defaults(void **state) {
  memorySet(&SAVE.slot, 0xFF, sizeof(SAVE.slot));

  saveSlotInit();

  assert_int_equal(SAVE.slot.version, 1);
  assert_int_equal(SAVE.slot.dataType, 0);
  assert_int_equal(SAVE.slot.cachedData.name[0], '\0');
  assert_true(SAVE.slot.cachedData.time.time == 0.0);
  assert_int_equal(SAVE.slot.cachedData.playerLevel, 0);
}

// ============================================================
// saveSlotInUse / saveSlotHasSaved
// ============================================================

static void test_saveSlotInUse(void **state) {
  saveSlotInit();

  assert_false(saveSlotInUse(&SAVE.slot.cachedData));

  stringCopy(
    SAVE.slot.cachedData.name, "Hero", sizeof(SAVE.slot.cachedData.name)
  );
  assert_true(saveSlotInUse(&SAVE.slot.cachedData));
}

static void test_saveSlotInUse_nullAsserts(void **state) {
  expect_assert_failure(saveSlotInUse(NULL));
}

static void test_saveSlotHasSaved(void **state) {
  saveSlotInit();

  assert_false(saveSlotHasSaved(&SAVE.slot.cachedData));

  // Writing to JSON stamps the current time as a side effect, so even a
  // pure serialize (no device write) flips "has ever saved" to true.
  char_t *json;
  size_t len;
  errorret_t ret = slotToJSON(&SAVE.slot, &json, &len);
  assert_true(errorIsOk(ret));
  assert_true(saveSlotHasSaved(&SAVE.slot.cachedData));

  free(json);
}

static void test_saveSlotHasSaved_nullAsserts(void **state) {
  expect_assert_failure(saveSlotHasSaved(NULL));
}

// ============================================================
// saveSlotWriteJSON
// ============================================================

static void test_saveSlotWriteJSON_nullAsserts(void **state) {
  // Content is never touched - both calls assert on a NULL doc/object
  // argument before slot itself would actually be read.
  saveslot_t slot;
  writeInit();

  expect_assert_failure(saveSlotWriteJSON(NULL, doc, object));
  expect_assert_failure(saveSlotWriteJSON(&slot, NULL, object));
  expect_assert_failure(saveSlotWriteJSON(&slot, doc, NULL));

  yyjson_mut_doc_free(doc);
}

// ============================================================
// saveSlotReadJSON
// ============================================================

static void test_saveSlotReadJSON_nullAsserts(void **state) {
  saveslot_t slot;

  yyjson_doc *readDoc = yyjson_read("{}", 2, 0);
  yyjson_val *readObject = yyjson_doc_get_root(readDoc);

  expect_assert_failure(saveSlotReadJSON(NULL, readObject));
  expect_assert_failure(saveSlotReadJSON(&slot, NULL));

  yyjson_doc_free(readDoc);
}

static void test_saveSlotReadJSON_roundTrip(void **state) {
  // saveSlotInit() only ever operates on SAVE.slot now, so that's the
  // write source here.
  saveSlotInit();
  SAVE.slot.version = 7;// deliberately non-default, not part of the JSON schema
  stringCopy(
    SAVE.slot.cachedData.name, "Hero", sizeof(SAVE.slot.cachedData.name)
  );
  SAVE.slot.cachedData.playerLevel = 42;
  // An in-use slot (non-empty name) requires a non-empty map name too -
  // see saveSlotNewGame/requireStrMin("mapName", 1) in saveSlotVer1ReadJSON.
  stringCopy(
    SAVE.slot.cachedData.mapName, "overworld",
    sizeof(SAVE.slot.cachedData.mapName)
  );

  char_t *json;
  size_t len;
  errorret_t writeRet = slotToJSON(&SAVE.slot, &json, &len);
  assert_true(errorIsOk(writeRet));

  const dusktimeepoch_t writtenTime = SAVE.slot.cachedData.time;

  // No pre-init needed - saveSlotReadJSON() fully resets/overwrites its
  // destination struct regardless of prior content.
  saveslot_t read;
  errorret_t readRet = slotFromJSON(&read, json);
  assert_true(errorIsOk(readRet));

  assert_true(stringEquals(read.cachedData.name, "Hero"));
  assert_int_equal(read.cachedData.playerLevel, 42);
  assert_true(stringEquals(read.cachedData.mapName, "overworld"));
  assert_true(read.cachedData.time.time == writtenTime.time);

  // version/dataType are struct-only bookkeeping, never serialized - the
  // reader resets them to the default regardless of the writer's version.
  assert_int_equal(read.version, 1);

  free(json);
}

static void test_saveSlotReadJSON_blankSlot_shortCircuits(void **state) {
  // Deliberately not saveSlotInit()'d - saveSlotReadJSON() fully resets its
  // destination struct itself before parsing, so these sentinel values are
  // only here to prove they get overwritten, not preserved.
  saveslot_t slot;
  memorySet(&slot, 0, sizeof(slot));
  stringCopy(slot.cachedData.name, "sentinel", sizeof(slot.cachedData.name));
  slot.cachedData.playerLevel = 999;

  // No "name" key (or an empty one) means a blank/never-used slot (see
  // saveSlotInUse) - the reader returns right after reading that, without
  // needing or validating time/mapName/partyMembers/partyOrder at all, so
  // this succeeds despite omitting fields that would otherwise be required.
  errorret_t ret = slotFromJSON(&slot, "{\"version\":1}");
  assert_true(errorIsOk(ret));

  assert_int_equal(slot.cachedData.name[0], '\0');
  assert_int_equal(slot.cachedData.mapName[0], '\0');
  // Not readInt32's own default of 1 - the early return happens before
  // playerLevel is ever read, leaving the zero-init saveSlotCurrentReadJSON
  // seeds ver1 with (see the memoryZero in saveSlotCurrentReadJSON).
  assert_int_equal(slot.cachedData.playerLevel, 0);
}

static void test_saveSlotReadJSON_inUseMissingMapName_errors(void **state) {
  saveslot_t slot;

  // "name" is present (in use) but "mapName" is missing - a real save
  // (via saveSlotNewGame) always has both, so this is corrupt.
  errorret_t ret = slotFromJSON(
    &slot,
    "{\"version\":1,\"name\":\"Hero\","
    "\"time\":{\"time\":1.0,\"timeZone\":0.0,\"offsetTime\":0.0}}"
  );
  assert_true(errorIsNotOk(ret));
  errorCatch(ret);
}

static void test_saveSlotReadJSON_missingTimeKey_errors(void **state) {
  saveslot_t slot;

  errorret_t ret = slotFromJSON(
    &slot, "{\"version\":1,\"name\":\"Hero\",\"playerLevel\":5}"
  );
  assert_true(errorIsNotOk(ret));
  errorCatch(ret);
}

static void test_saveSlotReadJSON_nameTooLong_errors(void **state) {
  saveslot_t slot;

  errorret_t ret = slotFromJSON(
    &slot,
    "{\"version\":1,\"name\":\"WayTooLongAName\","
    "\"time\":{\"time\":1.0,\"timeZone\":0.0,\"offsetTime\":0.0}}"
  );
  assert_true(errorIsNotOk(ret));
  errorCatch(ret);
}

static void test_saveSlotReadJSON_nonObjectRoot_errors(void **state) {
  saveslot_t slot;

  // A non-object root has no keys, so every field falls back to its
  // default - except "version" and "time", which are required and error
  // instead.
  errorret_t ret = slotFromJSON(&slot, "[]");
  assert_true(errorIsNotOk(ret));
  errorCatch(ret);
}

// ============================================================
// saveSlotReadJSON - version enforcement
// ============================================================

static void test_saveSlotReadJSON_versionMissing_errors(void **state) {
  saveslot_t slot;

  errorret_t ret = slotFromJSON(
    &slot,
    "{\"name\":\"Hero\","
    "\"time\":{\"time\":1.0,\"timeZone\":0.0,\"offsetTime\":0.0}}"
  );
  assert_true(errorIsNotOk(ret));
  errorCatch(ret);
}

static void test_saveSlotReadJSON_versionMismatch_errors(void **state) {
  saveslot_t slot;

  errorret_t ret = slotFromJSON(
    &slot,
    "{\"version\":999,\"name\":\"Hero\","
    "\"time\":{\"time\":1.0,\"timeZone\":0.0,\"offsetTime\":0.0}}"
  );
  assert_true(errorIsNotOk(ret));
  errorCatch(ret);
}

int main(void) {
  assertInit();
  const struct CMUnitTest tests[] = {
    cmocka_unit_test(test_saveSlotInit_defaults),

    cmocka_unit_test(test_saveSlotInUse),
    cmocka_unit_test(test_saveSlotInUse_nullAsserts),
    cmocka_unit_test(test_saveSlotHasSaved),
    cmocka_unit_test(test_saveSlotHasSaved_nullAsserts),

    cmocka_unit_test(test_saveSlotWriteJSON_nullAsserts),

    cmocka_unit_test(test_saveSlotReadJSON_nullAsserts),
    cmocka_unit_test(test_saveSlotReadJSON_roundTrip),
    cmocka_unit_test(test_saveSlotReadJSON_blankSlot_shortCircuits),
    cmocka_unit_test(test_saveSlotReadJSON_inUseMissingMapName_errors),
    cmocka_unit_test(test_saveSlotReadJSON_missingTimeKey_errors),
    cmocka_unit_test(test_saveSlotReadJSON_nameTooLong_errors),
    cmocka_unit_test(test_saveSlotReadJSON_nonObjectRoot_errors),
    cmocka_unit_test(test_saveSlotReadJSON_versionMissing_errors),
    cmocka_unit_test(test_saveSlotReadJSON_versionMismatch_errors),
  };

  return cmocka_run_group_tests(tests, NULL, NULL);
}