#ifndef _POSIX_C_SOURCE
#define _POSIX_C_SOURCE 200809L
#endif

#include "amduatd_fed_pull_apply.h"
#include "amduatd_fed_cursor.h"
#include "amduatd_store.h"

#include "amduat/asl/artifact_io.h"
#include "amduat/asl/asl_store_fs_meta.h"
#include "amduat/asl/ref_derive.h"
#include "amduat/hash/asl1.h"

#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

typedef struct {
  amduat_fed_record_t *records;
  size_t record_count;
  amduat_octets_t *artifact_bytes;
  bool fail_artifact;
  size_t fail_index;
  int fail_status;
  bool mutate_cursor;
  amduat_asl_store_t *store;
  amduat_asl_pointer_store_t *pointer_store;
  const amduatd_space_t *space;
  const char *peer_key;
} amduatd_test_pull_transport_t;

static int failures = 0;

static void expect(bool cond, const char *msg) {
  if (!cond) {
    fprintf(stderr, "FAIL: %s\n", msg);
    failures++;
  }
}

static char *amduatd_test_make_temp_dir(void) {
  char tmpl[] = "/tmp/amduatd-fed-pull-XXXXXX";
  char *dir = mkdtemp(tmpl);
  size_t len;
  char *copy;
  if (dir == NULL) {
    perror("mkdtemp");
    return NULL;
  }
  len = strlen(dir);
  copy = (char *)malloc(len + 1u);
  if (copy == NULL) {
    fprintf(stderr, "failed to allocate temp dir copy\n");
    return NULL;
  }
  memcpy(copy, dir, len + 1u);
  return copy;
}

static bool amduatd_test_clone_record(const amduat_fed_record_t *src,
                                      amduat_fed_record_t *dst) {
  if (src == NULL || dst == NULL) {
    return false;
  }
  *dst = *src;
  if (!amduat_reference_clone(src->id.ref, &dst->id.ref)) {
    return false;
  }
  return true;
}

static bool amduatd_test_pull_get_records(void *ctx,
                                          uint32_t domain_id,
                                          uint64_t from_logseq,
                                          uint64_t limit,
                                          int *out_status,
                                          amduat_fed_record_t **out_records,
                                          size_t *out_len,
                                          char **out_body) {
  amduatd_test_pull_transport_t *t = (amduatd_test_pull_transport_t *)ctx;
  amduat_fed_record_t *records = NULL;
  size_t i;
  (void)domain_id;
  (void)from_logseq;
  (void)limit;
  if (out_status == NULL || out_records == NULL || out_len == NULL) {
    return false;
  }
  *out_status = 200;
  *out_records = NULL;
  *out_len = 0;
  if (out_body != NULL) {
    *out_body = NULL;
  }
  if (t == NULL || t->record_count == 0u) {
    return true;
  }
  records = (amduat_fed_record_t *)calloc(t->record_count, sizeof(*records));
  if (records == NULL) {
    return false;
  }
  for (i = 0; i < t->record_count; ++i) {
    if (!amduatd_test_clone_record(&t->records[i], &records[i])) {
      free(records);
      return false;
    }
  }
  *out_records = records;
  *out_len = t->record_count;

  if (t->mutate_cursor && t->store != NULL && t->pointer_store != NULL &&
      t->space != NULL && t->peer_key != NULL) {
    amduatd_fed_cursor_record_t cursor;
    amduat_reference_t cursor_ref;
    amduatd_fed_cursor_record_t current;
    amduat_reference_t current_ref;
    const amduat_reference_t *expected_ref = NULL;
    amduatd_fed_cursor_record_init(&cursor);
    cursor.peer_key = strdup(t->peer_key);
    cursor.space_id = strdup((const char *)t->space->space_id.data);
    cursor.has_logseq = true;
    cursor.last_logseq = 99u;
    cursor.has_record_ref = true;
    if (cursor.peer_key != NULL && cursor.space_id != NULL &&
        amduat_reference_clone(t->records[0].id.ref,
                               &cursor.last_record_ref)) {
      amduatd_fed_cursor_record_init(&current);
      memset(&current_ref, 0, sizeof(current_ref));
      if (amduatd_fed_cursor_get(t->store,
                                t->pointer_store,
                                t->space,
                                t->peer_key,
                                &current,
                                &current_ref) == AMDUATD_FED_CURSOR_OK) {
        expected_ref = &current_ref;
      }
      (void)amduatd_fed_cursor_cas_set(t->store,
                                      t->pointer_store,
                                      t->space,
                                      t->peer_key,
                                      expected_ref,
                                      &cursor,
                                      &cursor_ref);
      if (expected_ref != NULL) {
        amduat_reference_free(&current_ref);
      }
      amduatd_fed_cursor_record_free(&current);
      amduat_reference_free(&cursor_ref);
    }
    amduatd_fed_cursor_record_free(&cursor);
  }

  return true;
}

static void amduatd_test_pull_free_records(void *ctx,
                                           amduat_fed_record_t *records,
                                           size_t len) {
  size_t i;
  (void)ctx;
  if (records == NULL) {
    return;
  }
  for (i = 0; i < len; ++i) {
    amduat_reference_free(&records[i].id.ref);
  }
  free(records);
}

static bool amduatd_test_pull_get_artifact(void *ctx,
                                           amduat_reference_t ref,
                                           int *out_status,
                                           amduat_octets_t *out_bytes,
                                           char **out_body) {
  amduatd_test_pull_transport_t *t = (amduatd_test_pull_transport_t *)ctx;
  size_t i;
  if (out_status == NULL || out_bytes == NULL) {
    return false;
  }
  *out_status = 404;
  *out_bytes = amduat_octets(NULL, 0u);
  if (out_body != NULL) {
    *out_body = NULL;
  }
  if (t == NULL) {
    return false;
  }
  for (i = 0; i < t->record_count; ++i) {
    if (!amduat_reference_eq(ref, t->records[i].id.ref)) {
      continue;
    }
    if (t->fail_artifact && i == t->fail_index) {
      *out_status = t->fail_status;
      return true;
    }
    if (!amduat_octets_clone(t->artifact_bytes[i], out_bytes)) {
      return false;
    }
    *out_status = 200;
    return true;
  }
  return true;
}

static bool amduatd_test_make_record(amduat_asl_store_t *store,
                                     const char *payload,
                                     uint64_t logseq,
                                     uint32_t domain_id,
                                     amduat_fed_record_t *out_record,
                                     amduat_octets_t *out_bytes) {
  amduat_artifact_t artifact;
  amduat_reference_t ref;
  amduat_octets_t artifact_bytes = amduat_octets(NULL, 0u);
  amduat_octets_t payload_bytes = amduat_octets(NULL, 0u);

  if (store == NULL || payload == NULL || out_record == NULL ||
      out_bytes == NULL) {
    return false;
  }

  if (!amduat_octets_clone(amduat_octets(payload, strlen(payload)),
                           &payload_bytes)) {
    return false;
  }
  if (!amduat_asl_artifact_from_bytes(payload_bytes,
                                      AMDUAT_ASL_IO_RAW,
                                      false,
                                      amduat_type_tag(0u),
                                      &artifact)) {
    amduat_octets_free(&payload_bytes);
    return false;
  }
  if (!amduat_asl_ref_derive(artifact,
                             store->config.encoding_profile_id,
                             store->config.hash_id,
                             &ref,
                             &artifact_bytes)) {
    amduat_asl_artifact_free(&artifact);
    return false;
  }
  amduat_asl_artifact_free(&artifact);
  amduat_octets_free(&artifact_bytes);

  memset(out_record, 0, sizeof(*out_record));
  out_record->id.type = AMDUAT_FED_REC_ARTIFACT;
  out_record->id.ref = ref;
  out_record->logseq = logseq;
  out_record->snapshot_id = 0u;
  out_record->log_prefix = 0u;
  out_record->meta.domain_id = domain_id;
  out_record->meta.visibility = 1u;
  out_record->meta.has_source = 0u;
  out_record->meta.source_domain = 0u;

  if (!amduat_octets_clone(amduat_octets(payload, strlen(payload)),
                           out_bytes)) {
    amduat_reference_free(&ref);
    return false;
  }

  return true;
}

static void amduatd_test_free_transport(amduatd_test_pull_transport_t *t) {
  size_t i;
  if (t == NULL) {
    return;
  }
  if (t->records != NULL) {
    for (i = 0; i < t->record_count; ++i) {
      amduat_reference_free(&t->records[i].id.ref);
    }
    free(t->records);
  }
  if (t->artifact_bytes != NULL) {
    for (i = 0; i < t->record_count; ++i) {
      amduat_octets_free(&t->artifact_bytes[i]);
    }
    free(t->artifact_bytes);
  }
  memset(t, 0, sizeof(*t));
}

int main(void) {
  char *root = amduatd_test_make_temp_dir();
  amduat_asl_store_fs_config_t cfg;
  amduatd_store_ctx_t store_ctx;
  amduat_asl_store_t store;
  amduat_asl_pointer_store_t pointer_store;
  amduatd_space_t space;
  amduatd_fed_cfg_t fed_cfg;

  if (root == NULL) {
    return 1;
  }

  memset(&cfg, 0, sizeof(cfg));
  if (!amduat_asl_store_fs_init_root(root, NULL, &cfg)) {
    fprintf(stderr, "failed to init store root\n");
    free(root);
    return 1;
  }
  memset(&store_ctx, 0, sizeof(store_ctx));
  memset(&store, 0, sizeof(store));
  if (!amduatd_store_init(&store,
                          &cfg,
                          &store_ctx,
                          root,
                          AMDUATD_STORE_BACKEND_INDEX)) {
    fprintf(stderr, "failed to init store\n");
    free(root);
    return 1;
  }
  if (!amduat_asl_pointer_store_init(&pointer_store, root)) {
    fprintf(stderr, "failed to init pointer store\n");
    free(root);
    return 1;
  }
  if (!amduatd_space_init(&space, "alpha", false)) {
    fprintf(stderr, "failed to init space\n");
    free(root);
    return 1;
  }
  amduatd_fed_cfg_init(&fed_cfg);
  fed_cfg.enabled = true;

  {
    amduatd_test_pull_transport_t t;
    amduatd_fed_pull_transport_t transport;
    amduat_fed_record_t *records = NULL;
    amduat_octets_t *bytes = NULL;
    amduatd_fed_pull_apply_report_t report;
    amduatd_fed_pull_apply_status_t rc;
    amduat_reference_t cursor_ref;
    amduatd_fed_cursor_record_t cursor;
    size_t i;

    memset(&t, 0, sizeof(t));
    records = (amduat_fed_record_t *)calloc(2u, sizeof(*records));
    bytes = (amduat_octets_t *)calloc(2u, sizeof(*bytes));
    if (records == NULL || bytes == NULL) {
      fprintf(stderr, "failed to alloc records\n");
      free(root);
      return 1;
    }
    if (!amduatd_test_make_record(&store,
                                  "hello",
                                  1u,
                                  1u,
                                  &records[0],
                                  &bytes[0]) ||
        !amduatd_test_make_record(&store,
                                  "world",
                                  2u,
                                  1u,
                                  &records[1],
                                  &bytes[1])) {
      fprintf(stderr, "failed to make records\n");
      free(root);
      return 1;
    }
    t.records = records;
    t.record_count = 2u;
    t.artifact_bytes = bytes;

    memset(&transport, 0, sizeof(transport));
    transport.ctx = &t;
    transport.get_records = amduatd_test_pull_get_records;
    transport.free_records = amduatd_test_pull_free_records;
    transport.get_artifact = amduatd_test_pull_get_artifact;

    amduatd_fed_pull_apply_report_init(&report);
    rc = amduatd_fed_pull_apply(&store,
                                &pointer_store,
                                &space,
                                "1",
                                NULL,
                                2u,
                                &fed_cfg,
                                &transport,
                                &report);
    expect(rc == AMDUATD_FED_PULL_APPLY_OK, "apply success");
    expect(report.applied_record_count == 2u, "applied record count");
    expect(report.cursor_advanced, "cursor advanced");

    for (i = 0; i < 2u; ++i) {
      amduat_artifact_t artifact;
      memset(&artifact, 0, sizeof(artifact));
      expect(amduat_asl_store_get(&store,
                                  records[i].id.ref,
                                  &artifact) == AMDUAT_ASL_STORE_OK,
             "artifact stored");
      amduat_asl_artifact_free(&artifact);
    }

    amduatd_fed_cursor_record_init(&cursor);
    memset(&cursor_ref, 0, sizeof(cursor_ref));
    expect(amduatd_fed_cursor_get(&store,
                                  &pointer_store,
                                  &space,
                                  "1",
                                  &cursor,
                                  &cursor_ref) == AMDUATD_FED_CURSOR_OK,
           "cursor get after apply");
    expect(cursor.has_logseq && cursor.last_logseq == 2u,
           "cursor advanced logseq");
    amduat_reference_free(&cursor_ref);
    amduatd_fed_cursor_record_free(&cursor);
    amduatd_fed_pull_apply_report_free(&report);
    amduatd_test_free_transport(&t);
  }

  {
    amduatd_test_pull_transport_t t;
    amduatd_fed_pull_transport_t transport;
    amduat_fed_record_t *records = NULL;
    amduat_octets_t *bytes = NULL;
    amduatd_fed_pull_apply_report_t report;
    amduatd_fed_pull_apply_status_t rc;
    amduatd_fed_cursor_record_t cursor;
    amduat_reference_t cursor_ref;
    uint64_t before_logseq = 0u;
    bool before_has_logseq = false;

    memset(&t, 0, sizeof(t));
    records = (amduat_fed_record_t *)calloc(2u, sizeof(*records));
    bytes = (amduat_octets_t *)calloc(2u, sizeof(*bytes));
    if (records == NULL || bytes == NULL) {
      fprintf(stderr, "failed to alloc records\n");
      free(root);
      return 1;
    }
    if (!amduatd_test_make_record(&store,
                                  "alpha",
                                  3u,
                                  1u,
                                  &records[0],
                                  &bytes[0]) ||
        !amduatd_test_make_record(&store,
                                  "beta",
                                  4u,
                                  1u,
                                  &records[1],
                                  &bytes[1])) {
      fprintf(stderr, "failed to make records\n");
      free(root);
      return 1;
    }
    t.records = records;
    t.record_count = 2u;
    t.artifact_bytes = bytes;
    t.fail_artifact = true;
    t.fail_index = 1u;
    t.fail_status = 503;

    memset(&transport, 0, sizeof(transport));
    transport.ctx = &t;
    transport.get_records = amduatd_test_pull_get_records;
    transport.free_records = amduatd_test_pull_free_records;
    transport.get_artifact = amduatd_test_pull_get_artifact;

    amduatd_fed_cursor_record_init(&cursor);
    memset(&cursor_ref, 0, sizeof(cursor_ref));
    expect(amduatd_fed_cursor_get(&store,
                                  &pointer_store,
                                  &space,
                                  "1",
                                  &cursor,
                                  &cursor_ref) == AMDUATD_FED_CURSOR_OK,
           "cursor present before partial");
    before_has_logseq = cursor.has_logseq;
    before_logseq = cursor.last_logseq;
    amduat_reference_free(&cursor_ref);
    amduatd_fed_cursor_record_free(&cursor);

    amduatd_fed_pull_apply_report_init(&report);
    rc = amduatd_fed_pull_apply(&store,
                                &pointer_store,
                                &space,
                                "1",
                                NULL,
                                2u,
                                &fed_cfg,
                                &transport,
                                &report);
    expect(rc == AMDUATD_FED_PULL_APPLY_ERR_STORE, "apply partial failure");
    expect(report.applied_record_count == 1u, "partial applied count");

    amduatd_fed_cursor_record_init(&cursor);
    memset(&cursor_ref, 0, sizeof(cursor_ref));
    expect(amduatd_fed_cursor_get(&store,
                                  &pointer_store,
                                  &space,
                                  "1",
                                  &cursor,
                                  &cursor_ref) == AMDUATD_FED_CURSOR_OK,
           "cursor present (from previous test)");
    expect(cursor.has_logseq == before_has_logseq, "cursor unchanged flag");
    expect(cursor.last_logseq == before_logseq, "cursor unchanged logseq");
    amduat_reference_free(&cursor_ref);
    amduatd_fed_cursor_record_free(&cursor);
    amduatd_fed_pull_apply_report_free(&report);
    amduatd_test_free_transport(&t);
  }

  {
    amduatd_test_pull_transport_t t;
    amduatd_fed_pull_transport_t transport;
    amduat_fed_record_t *records = NULL;
    amduat_octets_t *bytes = NULL;
    amduatd_fed_pull_apply_report_t report;
    amduatd_fed_pull_apply_status_t rc;
    amduatd_fed_cursor_record_t cursor;
    amduat_reference_t cursor_ref;

    memset(&t, 0, sizeof(t));
    records = (amduat_fed_record_t *)calloc(1u, sizeof(*records));
    bytes = (amduat_octets_t *)calloc(1u, sizeof(*bytes));
    if (records == NULL || bytes == NULL) {
      fprintf(stderr, "failed to alloc records\n");
      free(root);
      return 1;
    }
    if (!amduatd_test_make_record(&store,
                                  "gamma",
                                  5u,
                                  1u,
                                  &records[0],
                                  &bytes[0])) {
      fprintf(stderr, "failed to make record\n");
      free(root);
      return 1;
    }
    t.records = records;
    t.record_count = 1u;
    t.artifact_bytes = bytes;
    t.mutate_cursor = true;
    t.store = &store;
    t.pointer_store = &pointer_store;
    t.space = &space;
    t.peer_key = "1";

    memset(&transport, 0, sizeof(transport));
    transport.ctx = &t;
    transport.get_records = amduatd_test_pull_get_records;
    transport.free_records = amduatd_test_pull_free_records;
    transport.get_artifact = amduatd_test_pull_get_artifact;

    amduatd_fed_pull_apply_report_init(&report);
    rc = amduatd_fed_pull_apply(&store,
                                &pointer_store,
                                &space,
                                "1",
                                NULL,
                                1u,
                                &fed_cfg,
                                &transport,
                                &report);
    expect(rc == AMDUATD_FED_PULL_APPLY_ERR_CONFLICT, "cursor conflict");

    amduatd_fed_cursor_record_init(&cursor);
    memset(&cursor_ref, 0, sizeof(cursor_ref));
    expect(amduatd_fed_cursor_get(&store,
                                  &pointer_store,
                                  &space,
                                  "1",
                                  &cursor,
                                  &cursor_ref) == AMDUATD_FED_CURSOR_OK,
           "cursor present after conflict");
    expect(cursor.has_logseq && cursor.last_logseq == 99u,
           "cursor unchanged on conflict");
    amduat_reference_free(&cursor_ref);
    amduatd_fed_cursor_record_free(&cursor);
    amduatd_fed_pull_apply_report_free(&report);
    amduatd_test_free_transport(&t);
  }

  free(root);
  return failures == 0 ? 0 : 1;
}