/*
  Copyright 2011-2020 David Robillard <d@drobilla.net>

  Permission to use, copy, modify, and/or distribute this software for any
  purpose with or without fee is hereby granted, provided that the above
  copyright notice and this permission notice appear in all copies.

  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/

#undef NDEBUG

#include "serd/serd.h"

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

typedef struct {
  int             n_statements;
  const SerdNode* graph;
} ReaderTest;

static SerdStatus
test_sink(void*              handle,
          SerdStatementFlags flags,
          const SerdNode*    graph,
          const SerdNode*    subject,
          const SerdNode*    predicate,
          const SerdNode*    object)
{
  (void)flags;
  (void)subject;
  (void)predicate;
  (void)object;

  ReaderTest* rt = (ReaderTest*)handle;
  ++rt->n_statements;
  rt->graph = graph;
  return SERD_SUCCESS;
}

/// Reads a null byte after a statement, then succeeds again (like a socket)
static size_t
eof_test_read(void* buf, size_t size, size_t nmemb, void* stream)
{
  assert(size == 1);
  assert(nmemb == 1);
  (void)size;

  static const char* const string = "_:s1 <http://example.org/p> _:o1 .\n"
                                    "_:s2 <http://example.org/p> _:o2 .\n";

  size_t* const count = (size_t*)stream;

  // Normal reading for the first statement
  if (*count < 35) {
    *(char*)buf = string[*count];
    ++*count;
    return nmemb;
  }

  // EOF for the first read at the start of the second statement
  if (*count == 35) {
    assert(string[*count] == '_');
    ++*count;
    return 0;
  }

  if (*count >= strlen(string)) {
    return 0;
  }

  // Normal reading after the EOF, adjusting for the skipped index 35
  *(char*)buf = string[*count - 1];
  ++*count;
  return nmemb;
}

static int
eof_test_error(void* stream)
{
  (void)stream;
  return 0;
}

static void
test_read_chunks(void)
{
  ReaderTest* const rt     = (ReaderTest*)calloc(1, sizeof(ReaderTest));
  FILE* const       f      = tmpfile();
  static const char null   = 0;
  SerdSink*         sink   = serd_sink_new(rt, NULL);
  SerdReader*       reader = serd_reader_new(SERD_TURTLE, sink);

  assert(reader);
  assert(sink);
  assert(f);
  serd_sink_set_statement_func(sink, test_sink);

  SerdStatus st = serd_reader_start_stream(reader, f, NULL, false);
  assert(st == SERD_SUCCESS);

  // Write two statement separated by null characters
  fprintf(f, "@prefix eg: <http://example.org/> .\n");
  fprintf(f, "eg:s eg:p eg:o1 .\n");
  fwrite(&null, sizeof(null), 1, f);
  fprintf(f, "eg:s eg:p eg:o2 .\n");
  fwrite(&null, sizeof(null), 1, f);
  fseek(f, 0, SEEK_SET);

  // Read prefix
  st = serd_reader_read_chunk(reader);
  assert(st == SERD_SUCCESS);
  assert(rt->n_statements == 0);

  // Read first statement
  st = serd_reader_read_chunk(reader);
  assert(st == SERD_SUCCESS);
  assert(rt->n_statements == 1);

  // Read terminator
  st = serd_reader_read_chunk(reader);
  assert(st == SERD_FAILURE);
  assert(rt->n_statements == 1);

  // Read second statement (after null terminator)
  st = serd_reader_read_chunk(reader);
  assert(st == SERD_SUCCESS);
  assert(rt->n_statements == 2);

  // Read terminator
  st = serd_reader_read_chunk(reader);
  assert(st == SERD_FAILURE);
  assert(rt->n_statements == 2);

  // EOF
  st = serd_reader_read_chunk(reader);
  assert(st == SERD_FAILURE);
  assert(rt->n_statements == 2);

  serd_reader_free(reader);
  serd_sink_free(sink);
  fclose(f);
  free(rt);
}

static void
test_read_string(void)
{
  ReaderTest* rt     = (ReaderTest*)calloc(1, sizeof(ReaderTest));
  SerdSink*   sink   = serd_sink_new(rt, NULL);
  SerdReader* reader = serd_reader_new(SERD_TURTLE, sink);

  assert(reader);
  assert(sink);

  serd_sink_set_statement_func(sink, test_sink);

  // Test reading a string that ends exactly at the end of input (no newline)
  const SerdStatus st =
    serd_reader_read_string(reader,
                            "<http://example.org/s> <http://example.org/p> "
                            "<http://example.org/o> .");

  assert(!st);
  assert(rt->n_statements == 1);

  serd_reader_free(reader);
  serd_sink_free(sink);
  free(rt);
}

static void
test_writer(const char* const path)
{
  FILE*    fd  = fopen(path, "wb");
  SerdEnv* env = serd_env_new(SERD_EMPTY_STRING());
  assert(fd);

  SerdWriter* writer =
    serd_writer_new(SERD_TURTLE, 0, env, (SerdWriteFunc)fwrite, fd);
  assert(writer);

  serd_writer_chop_blank_prefix(writer, "tmp");
  serd_writer_chop_blank_prefix(writer, NULL);

  SerdNode* lit = serd_new_string(SERD_STRING("hello"));

  const SerdSink* const iface = serd_writer_sink(writer);
  assert(serd_sink_write_base(iface, lit));
  assert(serd_sink_write_prefix(iface, lit, lit));
  assert(serd_sink_write_end(iface, lit));

  static const uint8_t buf[]    = {0xEF, 0xBF, 0xBD, 0};
  const SerdStringView buf_view = {(const char*)buf, 3};

  SerdNode* s = serd_new_uri(SERD_EMPTY_STRING());
  SerdNode* p = serd_new_uri(SERD_STRING("http://example.org/pred"));
  SerdNode* o = serd_new_string(buf_view);

  // Write 3 invalid statements (should write nothing)
  const SerdNode* junk[][3] = {{s, o, o}, {o, p, o}, {s, o, p}};
  for (size_t i = 0; i < sizeof(junk) / (sizeof(SerdNode*) * 3); ++i) {
    assert(serd_sink_write(iface, 0, junk[i][0], junk[i][1], junk[i][2], NULL));
  }

  static const SerdStringView empty    = SERD_EMPTY_STRING();
  static const SerdStringView urn_Type = SERD_STRING("urn:Type");
  static const SerdStringView en       = SERD_STRING("en");

  SerdNode* const t         = serd_new_literal(buf_view, urn_Type, empty);
  SerdNode* const l         = serd_new_literal(buf_view, empty, en);
  const SerdNode* good[][3] = {{s, p, o}, {s, p, t}, {s, p, l}};

  for (size_t i = 0; i < sizeof(good) / (sizeof(SerdNode*) * 3); ++i) {
    assert(
      !serd_sink_write(iface, 0, good[i][0], good[i][1], good[i][2], NULL));
  }

  // Write statements with bad UTF-8 (should be replaced)
  const char           bad_str[] = {(char)0xFF, (char)0x90, 'h', 'i', 0};
  const SerdStringView bad_view  = {(const char*)bad_str, 4};
  SerdNode*            bad_lit   = serd_new_string(bad_view);
  SerdNode*            bad_uri   = serd_new_uri(bad_view);
  assert(!serd_sink_write(iface, 0, s, p, bad_lit, 0));
  assert(!serd_sink_write(iface, 0, s, p, bad_uri, 0));
  serd_node_free(bad_uri);
  serd_node_free(bad_lit);

  // Write 1 valid statement
  SerdNode* const hello = serd_new_string(SERD_STRING("hello"));
  assert(!serd_sink_write(iface, 0, s, p, hello, 0));
  serd_node_free(hello);

  serd_writer_free(writer);
  serd_node_free(lit);
  serd_node_free(o);
  serd_node_free(t);
  serd_node_free(l);

  // Test buffer sink
  SerdBuffer buffer = {NULL, 0};
  writer = serd_writer_new(SERD_TURTLE, 0, env, serd_buffer_sink, &buffer);

  SerdNode* const base = serd_new_uri(SERD_STRING("http://example.org/base"));

  serd_writer_set_base_uri(writer, base);

  serd_node_free(base);
  serd_writer_free(writer);
  char* out = serd_buffer_sink_finish(&buffer);

  assert(!strcmp(out, "@base <http://example.org/base> .\n"));
  serd_free(out);

  serd_node_free(p);
  serd_node_free(s);

  serd_env_free(env);
  fclose(fd);
}

static void
test_reader(const char* path)
{
  ReaderTest*     rt     = (ReaderTest*)calloc(1, sizeof(ReaderTest));
  SerdSink* const sink   = serd_sink_new(rt, NULL);
  SerdReader*     reader = serd_reader_new(SERD_TURTLE, sink);

  assert(sink);
  assert(reader);
  serd_sink_set_statement_func(sink, test_sink);

  SerdNode* g = serd_new_uri(SERD_STRING("http://example.org/"));
  serd_reader_set_default_graph(reader, g);
  serd_reader_add_blank_prefix(reader, "tmp");

#if defined(__GNUC__)
#  pragma GCC diagnostic push
#  pragma GCC diagnostic ignored "-Wnonnull"
#endif
  serd_reader_add_blank_prefix(reader, NULL);
#if defined(__GNUC__)
#  pragma GCC diagnostic pop
#endif

  serd_node_free(g);

  assert(serd_reader_read_file(reader, "http://notafile"));
  assert(serd_reader_read_file(reader, "file:///better/not/exist"));
  assert(serd_reader_read_file(reader, "file://"));

  const SerdStatus st = serd_reader_read_file(reader, path);
  assert(!st);
  assert(rt->n_statements == 6);
  assert(rt->graph && serd_node_string(rt->graph) &&
         !strcmp(serd_node_string(rt->graph), "http://example.org/"));

  assert(serd_reader_read_string(reader, "This isn't Turtle at all."));

  // A read of a big page hits EOF then fails to read chunks immediately
  {
    FILE* temp = tmpfile();
    assert(temp);
    fprintf(temp, "_:s <http://example.org/p> _:o .\n");
    fflush(temp);
    fseek(temp, 0L, SEEK_SET);

    serd_reader_start_stream(reader, temp, NULL, true);

    assert(serd_reader_read_chunk(reader) == SERD_SUCCESS);
    assert(serd_reader_read_chunk(reader) == SERD_FAILURE);
    assert(serd_reader_read_chunk(reader) == SERD_FAILURE);

    serd_reader_end_stream(reader);
    fclose(temp);
  }

  // A byte-wise reader that hits EOF once then continues (like a socket)
  {
    size_t n_reads = 0;
    serd_reader_start_source_stream(reader,
                                    (SerdReadFunc)eof_test_read,
                                    (SerdStreamErrorFunc)eof_test_error,
                                    &n_reads,
                                    NULL,
                                    1);

    assert(serd_reader_read_chunk(reader) == SERD_SUCCESS);
    assert(serd_reader_read_chunk(reader) == SERD_FAILURE);
    assert(serd_reader_read_chunk(reader) == SERD_SUCCESS);
    assert(serd_reader_read_chunk(reader) == SERD_FAILURE);
  }

  serd_reader_free(reader);
  serd_sink_free(sink);
  free(rt);
}

int
main(void)
{
  test_read_chunks();
  test_read_string();

  const char* const path = "serd_test.ttl";
  test_writer(path);
  test_reader(path);

  printf("Success\n");
  return 0;
}