/*
  Copyright 2011-2021 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.
*/

#include "console.h"

#include "serd/serd.h"

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

/* Application (after parsing command-line arguments) */

// All options
typedef struct {
  SerdCommonOptions  common;
  const char*        root_uri;
  const char*        input_string;
  const char*        collation;
  char* const*       inputs;
  intptr_t           n_inputs;
  SerdStatementOrder order;
  SerdDescribeFlags  flags;
} Options;

static bool
input_has_graphs(const Options opts)
{
  if (opts.common.input.syntax) {
    return serd_syntax_has_graphs(opts.common.input.syntax);
  }

  for (intptr_t i = 0u; i < opts.n_inputs; ++i) {
    if (serd_syntax_has_graphs(serd_guess_syntax(opts.inputs[i]))) {
      return true;
    }
  }

  return false;
}

// Run the tool using the given options
static SerdStatus
run(const Options opts)
{
  SerdTool app = {{NULL, NULL, NULL}, NULL, NULL, NULL};

  // Set up the writing environment
  SerdStatus st = SERD_SUCCESS;
  if ((st = serd_tool_setup(&app, "serd-sort", opts.common))) {
    serd_tool_cleanup(app);
    return st;
  }

  // Determine the default order to store statements in the model
  const bool               with_graphs   = input_has_graphs(opts);
  const SerdStatementOrder default_order = opts.collation ? opts.order
                                           : with_graphs  ? SERD_ORDER_GSPO
                                                          : SERD_ORDER_SPO;

  const SerdModelFlags flags =
    (SerdModelFlags)(with_graphs * SERD_STORE_GRAPHS);

  SerdModel* const model = serd_model_new(app.world, default_order, flags);

  if (!opts.collation) {
    // If we are pretty-printing, we need an O** index
    serd_model_add_index(model, SERD_ORDER_OPS);

    if (with_graphs) {
      // If we have graphs we still need the SPO index for finding subjects
      serd_model_add_index(model, SERD_ORDER_SPO);
    }
  }

  // Read all the inputs into an inserter to load the model
  SerdSink* const inserter = serd_inserter_new(model, NULL);
  if (st || (st = serd_read_inputs(app.world,
                                   opts.common,
                                   app.env,
                                   opts.n_inputs,
                                   opts.inputs,
                                   inserter))) {
    serd_sink_free(inserter);
    serd_model_free(model);
    serd_tool_cleanup(app);
    return st;
  }

  // Write the model to the output
  const SerdSink* const target = serd_writer_sink(app.writer);
  if (opts.collation) {
    SerdCursor* const cursor = serd_model_begin_ordered(model, opts.order);

    serd_env_write_prefixes(app.env, target);

    for (const SerdStatement* statement = NULL;
         !st && (statement = serd_cursor_get(cursor));
         serd_cursor_advance(cursor)) {
      st = serd_sink_write_statement(target, 0u, statement);
    }

    serd_cursor_free(cursor);
  } else {
    SerdCursor* const cursor = serd_model_begin(model);

    serd_env_write_prefixes(app.env, target);

    st = serd_describe_range(cursor, target, opts.flags);

    serd_cursor_free(cursor);
  }

  if (!st) {
    st = serd_writer_finish(app.writer);
  }

  serd_sink_free(inserter);
  serd_model_free(model);

  const SerdStatus cst = serd_tool_cleanup(app);
  return st ? st : cst;
}

/* Command-line interface (before setting up serd) */

static SerdStatus
parse_statement_order(const char* const string, SerdStatementOrder* const order)
{
  static const char* const strings[] = {"SPO",
                                        "SOP",
                                        "OPS",
                                        "OSP",
                                        "PSO",
                                        "POS",
                                        "GSPO",
                                        "GSOP",
                                        "GOPS",
                                        "GOSP",
                                        "GPSO",
                                        "GPOS",
                                        NULL};

  for (unsigned i = 0; strings[i]; ++i) {
    if (!strcmp(string, strings[i])) {
      *order = (SerdStatementOrder)i;
      return SERD_SUCCESS;
    }
  }

  return SERD_BAD_ARG;
}

static int
print_usage(const char* const name, const bool error)
{
  static const char* const description =
    "Reorder RDF data by loading everything into a model then writing it.\n"
    "INPUT can be a local filename, or \"-\" to read from standard input.\n\n"
    "  -B BASE_URI   Base URI or path for resolving relative references.\n"
    "  -I SYNTAX     Input syntax (turtle/ntriples/trig/nquads),\n"
    "                or option (lax/variables/relative/global/generated).\n"
    "  -O SYNTAX     Output syntax (empty/turtle/ntriples/nquads),\n"
    "                or option (ascii/expanded/verbatim/terse/lax).\n"
    "  -V            Display version information and exit.\n"
    "  -b BYTES      I/O block size.\n"
    "  -c COLLATION  An optional \"G\" then the letters \"SPO\" in any order.\n"
    "  -h            Display this help and exit.\n"
    "  -k BYTES      Parser stack size.\n"
    "  -o FILENAME   Write output to FILENAME instead of stdout.\n"
    "  -t            Do not write type as \"a\" before other properties.\n";

  FILE* const os = error ? stderr : stdout;
  fprintf(os, "%s", error ? "\n" : "");
  fprintf(os, "Usage: %s [OPTION]... INPUT...\n", name);
  fprintf(os, "%s", description);
  return error;
}

// Parse the option pointed to by `iter`, and advance it to the next one
static SerdStatus
parse_option(OptionIter* const iter, Options* const opts)
{
#define ARG_ERRORF(fmt, ...) \
  fprintf(stderr, "%s: " fmt, iter->argv[0], __VA_ARGS__)

  SerdStatus st = serd_parse_common_option(iter, &opts->common);
  if (st != SERD_FAILURE) {
    return st;
  }

  const char opt = iter->argv[iter->a][iter->f];
  switch (opt) {
  case 'R':
    return serd_get_argument(iter, &opts->root_uri);

  case 'V':
    return serd_print_version("serd-sort");

  case 'c':
    if (!(st = serd_get_argument(iter, &opts->collation))) {
      if ((st = parse_statement_order(opts->collation, &opts->order))) {
        ARG_ERRORF("unknown collation \"%s\"\n", opts->collation);
        return st;
      }
    }
    return st;

  case 'h':
    print_usage(iter->argv[0], false);
    return SERD_FAILURE;

  case 's':
    return serd_get_argument(iter, &opts->input_string);

  case 't':
    opts->common.output.flags |= SERD_WRITE_RDF_TYPE;
    opts->flags |= SERD_NO_TYPE_FIRST;
    return serd_option_iter_advance(iter);

  default:
    break;
  }

  ARG_ERRORF("invalid option -- '%c'\n", opt);
  return SERD_BAD_ARG;

#undef ARG_ERRORF
}

int
main(const int argc, char* const* const argv)
{
  char  default_input[]  = "-";
  char* default_inputs[] = {default_input};

  Options opts = {{"",
                   NULL,
                   4096u,
                   1048576u,
                   {SERD_SYNTAX_EMPTY, 0u, false},
                   {SERD_SYNTAX_EMPTY, 0u, false}},
                  "",
                  NULL,
                  NULL,
                  NULL,
                  0u,
                  SERD_ORDER_SPO,
                  0u};

  // Parse all command line options (which must precede inputs)
  SerdStatus st   = SERD_SUCCESS;
  OptionIter iter = {argv, argc, 1, 1};
  while (!serd_option_iter_is_end(iter)) {
    if ((st = parse_option(&iter, &opts))) {
      return (st == SERD_FAILURE) ? 0 : print_usage(argv[0], true);
    }
  }

  // Every argument past the last option is an input
  opts.inputs   = argv + iter.a;
  opts.n_inputs = argc - iter.a;
  if (opts.n_inputs + (bool)opts.input_string == 0) {
    opts.n_inputs = 1;
    opts.inputs   = default_inputs;
  }

  // Don't add prefixes to blank node labels if there is only one input
  if (opts.n_inputs + (bool)opts.input_string == 1) {
    opts.common.input.flags |= SERD_READ_GLOBAL;
  }

  return run(opts) > SERD_FAILURE;
}