/*
  Copyright (c) 2006-2013, 2015 Gordon Gremme <gordon@gremme.org>
  Copyright (c) 2006-2008       Center for Bioinformatics, University of Hamburg

  Permission to use, copy, modify, and 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.

  THE 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 <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include "core/assert_api.h"
#include "core/fasta.h"
#include "core/file.h"
#include "core/hashmap.h"
#include "core/ma.h"
#include "core/unused_api.h"
#include "core/string_distri.h"
#include "core/cstr_table.h"
#include "core/str_api.h"
#include "core/warning_api.h"
#include "extended/genome_node.h"
#include "extended/gff3_defines.h"
#include "extended/gff3_output.h"
#include "extended/gff3_visitor.h"
#include "extended/node_visitor_api.h"

struct GtGFF3Visitor {
  const GtNodeVisitor parent_instance;
  bool version_string_shown,
       retain_ids,
       fasta_directive_shown,
       allow_nonunique_ids;
  GtStringDistri *id_counter;
  GtHashmap *feature_node_to_id_array,
            *feature_node_to_unique_id_str;
  GtUword fasta_width;
  GtFile *outfp;
  GtStr *outstr;
  GtCstrTable *used_ids;
};

typedef struct {
  GtHashmap *gt_feature_node_to_id_array;
  const char *id;
} AddIDInfo;

typedef struct {
  bool *attribute_shown;
  GtFile *outfp;
  GtStr *outstr;
} ShowAttributeInfo;

#define gff3_visitor_cast(GV)\
        gt_node_visitor_cast(gt_gff3_visitor_class(), GV)

static void gff3_version_string(GtNodeVisitor *nv)
{
  GtGFF3Visitor *gff3_visitor = gff3_visitor_cast(nv);
  gt_assert(gff3_visitor);
  if (!gff3_visitor->version_string_shown) {
    if (!gff3_visitor->outstr) {
      gt_file_xprintf(gff3_visitor->outfp, "%s %u\n", GT_GFF_VERSION_PREFIX,
                      GT_GFF_VERSION);
    } else {
      gt_str_append_cstr(gff3_visitor->outstr, GT_GFF_VERSION_PREFIX);
      gt_str_append_cstr(gff3_visitor->outstr, " ");
      gt_str_append_uint(gff3_visitor->outstr, GT_GFF_VERSION);
      gt_str_append_char(gff3_visitor->outstr, '\n');
    }
    gff3_visitor->version_string_shown = true;
  }
}

static void gff3_visitor_free(GtNodeVisitor *nv)
{
  GtGFF3Visitor *gff3_visitor = gff3_visitor_cast(nv);
  gt_assert(gff3_visitor);
  gt_string_distri_delete(gff3_visitor->id_counter);
  gt_hashmap_delete(gff3_visitor->feature_node_to_id_array);
  gt_hashmap_delete(gff3_visitor->feature_node_to_unique_id_str);
  gt_cstr_table_delete(gff3_visitor->used_ids);
  gt_str_delete(gff3_visitor->outstr);
  gt_file_delete(gff3_visitor->outfp);
}

static int gff3_visitor_comment_node(GtNodeVisitor *nv, GtCommentNode *cn,
                                     GT_UNUSED GtError *err)
{
  GtGFF3Visitor *gff3_visitor;
  gt_error_check(err);
  gff3_visitor = gff3_visitor_cast(nv);
  gt_assert(nv && cn);
  gff3_version_string(nv);
  if (!gff3_visitor->outstr) {
    gt_file_xprintf(gff3_visitor->outfp, "#%s\n",
                    gt_comment_node_get_comment(cn));
  } else  {
    gt_str_append_char(gff3_visitor->outstr, '#');
    gt_str_append_cstr(gff3_visitor->outstr, gt_comment_node_get_comment(cn));
    gt_str_append_char(gff3_visitor->outstr, '\n');
  }
  return 0;
}

static int add_id(GtFeatureNode *fn, void *data, GT_UNUSED GtError *err)
{
  AddIDInfo *info = (AddIDInfo*) data;
  GtArray *parent_features = NULL;
  gt_error_check(err);
  gt_assert(fn && info && info->gt_feature_node_to_id_array && info->id);
  parent_features = gt_hashmap_get(info->gt_feature_node_to_id_array, fn);
  if (!parent_features) {
    parent_features = gt_array_new(sizeof (char*));
    gt_hashmap_add(info->gt_feature_node_to_id_array, fn, parent_features);
  }
  gt_array_add(parent_features, info->id);
  return 0;
}

static void show_attribute(const char *attr_name, const char *attr_value,
                           void *data)
{
  ShowAttributeInfo *info = (ShowAttributeInfo*) data;
  gt_assert(attr_name && attr_value && info);
  if (strcmp(attr_name, GT_GFF_ID) && strcmp(attr_name, GT_GFF_PARENT)) {
    if (*info->attribute_shown) {
      if (!info->outstr)
        gt_file_xfputc(';', info->outfp);
      else
        gt_str_append_char(info->outstr, ';');
    } else
      *info->attribute_shown = true;
    if (!info->outstr)
      gt_file_xprintf(info->outfp, "%s=%s", attr_name, attr_value);
    else {
      gt_str_append_cstr(info->outstr, attr_name);
      gt_str_append_char(info->outstr, '=');
      gt_str_append_cstr(info->outstr, attr_value);
    }
  }
}

static int gff3_show_feature_node(GtFeatureNode *fn, void *data,
                                  GT_UNUSED GtError *err)
{
  bool part_shown = false;
  GtGFF3Visitor *gff3_visitor = (GtGFF3Visitor*) data;
  GtArray *parent_features = NULL;
  ShowAttributeInfo info;
  GtUword i;
  GtStr *id;

  gt_error_check(err);
  gt_assert(fn && gff3_visitor);

  /* output leading part */
  if (!gff3_visitor->outstr) {
    gt_gff3_output_leading(fn, gff3_visitor->outfp);
  } else {
    gt_gff3_output_leading_str(fn, gff3_visitor->outstr);
  }

  /* show unique id part of attributes */
  if ((id = gt_hashmap_get(gff3_visitor->feature_node_to_unique_id_str, fn))) {
    if (!gff3_visitor->outstr)
      gt_file_xprintf(gff3_visitor->outfp, "%s=%s", GT_GFF_ID, gt_str_get(id));
    else {
      gt_str_append_cstr(gff3_visitor->outstr, GT_GFF_ID);
      gt_str_append_char(gff3_visitor->outstr, '=');
      gt_str_append_cstr(gff3_visitor->outstr, gt_str_get(id));
    }
    part_shown = true;
  }

  /* show parent part of attributes */
  parent_features = gt_hashmap_get(gff3_visitor->feature_node_to_id_array, fn);
  if (gt_array_size(parent_features)) {
    if (part_shown) {
      if (!gff3_visitor->outstr)
        gt_file_xfputc(';', gff3_visitor->outfp);
      else
        gt_str_append_char(gff3_visitor->outstr, ';');
    }
    if (!gff3_visitor->outstr)
      gt_file_xprintf(gff3_visitor->outfp, "%s=", GT_GFF_PARENT);
    else {
      gt_str_append_cstr(gff3_visitor->outstr, GT_GFF_PARENT);
      gt_str_append_char(gff3_visitor->outstr, '=');
    }
    for (i = 0; i < gt_array_size(parent_features); i++) {
      if (i) {
        if (!gff3_visitor->outstr)
          gt_file_xfputc(',', gff3_visitor->outfp);
        else
          gt_str_append_char(gff3_visitor->outstr, ',');
      }
      if (!gff3_visitor->outstr) {
        gt_file_xprintf(gff3_visitor->outfp, "%s",
                        *(char**) gt_array_get(parent_features, i));
      } else {
        gt_str_append_cstr(gff3_visitor->outstr,
                           *(char**) gt_array_get(parent_features, i));
      }
    }
    part_shown = true;
  }

  /* show missing part of attributes */
  info.attribute_shown = &part_shown;
  info.outfp = gff3_visitor->outfp;
  info.outstr = gff3_visitor->outstr;
  gt_feature_node_foreach_attribute(fn, show_attribute, &info);

  /* show dot if no attributes have been shown */
  if (!part_shown) {
    if (!gff3_visitor->outstr)
      gt_file_xfputc('.', gff3_visitor->outfp);
    else
      gt_str_append_char(gff3_visitor->outstr, '.');
  }

  /* show terminal newline */
  if (!gff3_visitor->outstr)
    gt_file_xfputc('\n', gff3_visitor->outfp);
  else
    gt_str_append_char(gff3_visitor->outstr, '\n');

  return 0;
}

static GtStr* create_unique_id(GtGFF3Visitor *gff3_visitor, GtFeatureNode *fn)
{
  const char *type;
  GtStr *id;
  gt_assert(gff3_visitor && fn);
  type = gt_feature_node_get_type(fn);

  /* increase id counter */
  gt_string_distri_add(gff3_visitor->id_counter, type);

  /* build id string */
  id = gt_str_new_cstr(type);
  gt_str_append_uword(id, gt_string_distri_get(gff3_visitor->id_counter, type));

  /* store (unique) id */
  gt_hashmap_add(gff3_visitor->feature_node_to_unique_id_str, fn, id);

  return id;
}

static void make_unique_id_string(GtStr *current_id, GtUword counter)
{
  /* name => name.1 */
  gt_str_append_char(current_id, '.');
  gt_str_append_uword(current_id, counter);
}

static bool id_string_is_unique(GtStr *id, GtStr *buf, GtCstrTable *tab,
                                GtUword i)
{
  gt_str_reset(buf);
  gt_str_append_str(buf, id);
  make_unique_id_string(buf, i);
  return !gt_cstr_table_get(tab, gt_str_get(buf));
}

static GtStr* make_id_unique(GtGFF3Visitor *gff3_visitor, GtFeatureNode *fn)
{
  GtUword i = 1;
  GtStr *id = gt_str_new_cstr(gt_feature_node_get_attribute(fn, "ID"));

  if (!gff3_visitor->allow_nonunique_ids) {
    if (gt_cstr_table_get(gff3_visitor->used_ids, gt_str_get(id))) {
      GtStr *buf = gt_str_new();
      while (!id_string_is_unique(id, buf, gff3_visitor->used_ids, i++));
      gt_warning("feature ID \"%s\" not unique: changing to %s", gt_str_get(id),
                                                               gt_str_get(buf));
      gt_str_set(id, gt_str_get(buf));
      gt_str_delete(buf);
    }
    /* update table with the new id */
    gt_cstr_table_add(gff3_visitor->used_ids, gt_str_get(id));
  }

  /* store (unique) id */
  gt_hashmap_add(gff3_visitor->feature_node_to_unique_id_str, fn, id);

  return id;
}

static int store_ids(GtFeatureNode *fn, void *data, GtError *err)
{
  GtGFF3Visitor *gff3_visitor = (GtGFF3Visitor*) data;
  AddIDInfo add_id_info;
  int had_err = 0;
  GtStr *id;

  gt_error_check(err);
  gt_assert(fn && gff3_visitor);

  if (gt_feature_node_has_children(fn) || gt_feature_node_is_multi(fn) ||
      (gff3_visitor->retain_ids && gt_feature_node_get_attribute(fn, "ID"))) {
    if (gt_feature_node_is_multi(fn)) {
      id = gt_hashmap_get(gff3_visitor->feature_node_to_unique_id_str,
                          gt_feature_node_get_multi_representative(fn));
      if (!id) {
        /* the representative does not have its own id yet -> create it */
        if (gff3_visitor->retain_ids) {
          id = make_id_unique(gff3_visitor,
                              gt_feature_node_get_multi_representative(fn));
        }
        else {
          id = create_unique_id(gff3_visitor,
                                gt_feature_node_get_multi_representative(fn));
        }
      }
      /* store id for feature, if the feature was not the representative */
      if (gt_feature_node_get_multi_representative(fn) != fn) {
        gt_hashmap_add(gff3_visitor->feature_node_to_unique_id_str, fn,
                       gt_str_ref(id));
      }
    }
    else {
      if (gff3_visitor->retain_ids)
        id = make_id_unique(gff3_visitor, fn);
      else
        id = create_unique_id(gff3_visitor, fn);
    }
    /* for each child -> store the parent feature in the hash map */
    add_id_info.gt_feature_node_to_id_array =
      gff3_visitor->feature_node_to_id_array,
    add_id_info.id = gt_str_get(id);
    had_err = gt_feature_node_traverse_direct_children(fn, &add_id_info, add_id,
                                                       err);
  }
  return had_err;
}

static int gff3_visitor_feature_node(GtNodeVisitor *nv, GtFeatureNode *fn,
                                     GtError *err)
{
  GtGFF3Visitor *gff3_visitor;
  int had_err;
  gt_error_check(err);
  gff3_visitor = gff3_visitor_cast(nv);

  gff3_version_string(nv);

  had_err = gt_feature_node_traverse_children(fn, gff3_visitor, store_ids, true,
                                              err);
  if (!had_err) {
    if (gt_feature_node_is_tree(fn)) {
      had_err = gt_feature_node_traverse_children(fn, gff3_visitor,
                                                  gff3_show_feature_node, true,
                                                  err);
    }
    else {
      /* got a DAG -> traverse in topologically sorted depth first fashion to
         make sure that the 'Parent' attributes are shown in correct order */
      had_err =
        gt_feature_node_traverse_children_top(fn, gff3_visitor,
                                              gff3_show_feature_node, err);
    }
  }

  /* reset hashmaps */
  gt_hashmap_reset(gff3_visitor->feature_node_to_id_array);
  gt_hashmap_reset(gff3_visitor->feature_node_to_unique_id_str);

  /* show terminator, if the feature has children (otherwise it is clear that
     the feature is complete, because no ID attribute has been shown) */
  if (gt_feature_node_has_children(fn) ||
      (gff3_visitor->retain_ids && gt_feature_node_get_attribute(fn, "ID"))) {
    if (!gff3_visitor->outstr)
      gt_file_xprintf(gff3_visitor->outfp, "%s\n", GT_GFF_TERMINATOR);
    else {
      gt_str_append_cstr(gff3_visitor->outstr, GT_GFF_TERMINATOR);
      gt_str_append_char(gff3_visitor->outstr, '\n');
    }
  }

  return had_err;
}

static int gff3_visitor_meta_node(GtNodeVisitor *nv, GtMetaNode *mn,
                                  GT_UNUSED GtError *err)
{
  GtGFF3Visitor *gff3_visitor;
  const char *data;
  gt_error_check(err);
  gff3_visitor = gff3_visitor_cast(nv);
  gt_assert(nv && mn);
  if (!gff3_visitor->version_string_shown) {
    if (strncmp(gt_meta_node_get_directive(mn), GT_GFF_VERSION_DIRECTIVE,
                strlen(GT_GFF_VERSION_DIRECTIVE)) == 0
          || strncmp(gt_meta_node_get_directive(mn), GT_GVF_VERSION_DIRECTIVE,
                     strlen(GT_GVF_VERSION_DIRECTIVE)) == 0) {
      gff3_visitor->version_string_shown = true;
    } else {
      gff3_version_string(nv);
    }
  }
  data = gt_meta_node_get_data(mn);
  if (!gff3_visitor->outstr) {
    if (data) {
      gt_file_xprintf(gff3_visitor->outfp, "##%s %s\n",
                      gt_meta_node_get_directive(mn), data);
    } else {
      gt_file_xprintf(gff3_visitor->outfp, "##%s\n",
                      gt_meta_node_get_directive(mn));
    }
  } else {
    gt_str_append_cstr(gff3_visitor->outstr, "##");
    gt_str_append_cstr(gff3_visitor->outstr, gt_meta_node_get_directive(mn));
    if (data) {
      gt_str_append_char(gff3_visitor->outstr, ' ');
      gt_str_append_cstr(gff3_visitor->outstr, data);
    }
    gt_str_append_char(gff3_visitor->outstr, '\n');
  }
  return 0;
}

static int gff3_visitor_region_node(GtNodeVisitor *nv, GtRegionNode *rn,
                                    GT_UNUSED GtError *err)
{
  GtGFF3Visitor *gff3_visitor;
  gt_error_check(err);
  gff3_visitor = gff3_visitor_cast(nv);
  gt_assert(nv && rn);
  gff3_version_string(nv);
  if (!gff3_visitor->outstr) {
    gt_file_xprintf(gff3_visitor->outfp, "%s   %s "GT_WU" "GT_WU"\n",
                    GT_GFF_SEQUENCE_REGION,
                    gt_str_get(gt_genome_node_get_seqid((GtGenomeNode*) rn)),
                    gt_genome_node_get_start((GtGenomeNode*) rn),
                    gt_genome_node_get_end((GtGenomeNode*) rn));
  } else {
    gt_str_append_cstr(gff3_visitor->outstr, GT_GFF_SEQUENCE_REGION);
    gt_str_append_cstr(gff3_visitor->outstr, "   ");
    gt_str_append_cstr(gff3_visitor->outstr,
                      gt_str_get(gt_genome_node_get_seqid((GtGenomeNode*) rn)));
    gt_str_append_char(gff3_visitor->outstr, ' ');
    gt_str_append_uword(gff3_visitor->outstr,
                                  gt_genome_node_get_start((GtGenomeNode*) rn));
    gt_str_append_char(gff3_visitor->outstr, ' ');
    gt_str_append_uword(gff3_visitor->outstr,
                                  gt_genome_node_get_end((GtGenomeNode*) rn));
    gt_str_append_char(gff3_visitor->outstr, '\n');
  }
  return 0;
}

static int gff3_visitor_sequence_node(GtNodeVisitor *nv, GtSequenceNode *sn,
                                      GT_UNUSED GtError *err)
{
  GtGFF3Visitor *gff3_visitor;
  gt_error_check(err);
  gff3_visitor = gff3_visitor_cast(nv);
  gt_assert(nv && sn);
  gff3_version_string(nv);
  if (!gff3_visitor->fasta_directive_shown) {
    if (!gff3_visitor->outstr)
      gt_file_xprintf(gff3_visitor->outfp, "%s\n", GT_GFF_FASTA_DIRECTIVE);
    else {
      gt_str_append_cstr(gff3_visitor->outstr, GT_GFF_FASTA_DIRECTIVE);
      gt_str_append_char(gff3_visitor->outstr, '\n');
    }
    gff3_visitor->fasta_directive_shown = true;
  }
  if (!gff3_visitor->outstr) {
    gt_fasta_show_entry(gt_sequence_node_get_description(sn),
                        gt_sequence_node_get_sequence(sn),
                        gt_sequence_node_get_sequence_length(sn),
                        gff3_visitor->fasta_width, gff3_visitor->outfp);
  } else {
    gt_fasta_show_entry_str(gt_sequence_node_get_description(sn),
                            gt_sequence_node_get_sequence(sn),
                            gt_sequence_node_get_sequence_length(sn),
                            gff3_visitor->fasta_width, gff3_visitor->outstr);
  }
  return 0;
}

static int gff3_visitor_eof_node(GtNodeVisitor *nv, GT_UNUSED GtEOFNode *en,
                                 GT_UNUSED GtError *err)
{
  gt_error_check(err);
  gt_assert(nv && en);
  gff3_version_string(nv);
  return 0;
}

const GtNodeVisitorClass* gt_gff3_visitor_class()
{
  static GtNodeVisitorClass *nvc = NULL;
  if (!nvc) {
    nvc = gt_node_visitor_class_new(sizeof (GtGFF3Visitor),
                                    gff3_visitor_free,
                                    gff3_visitor_comment_node,
                                    gff3_visitor_feature_node,
                                    gff3_visitor_region_node,
                                    gff3_visitor_sequence_node,
                                    gff3_visitor_eof_node);
    gt_node_visitor_class_set_meta_node_func(nvc, gff3_visitor_meta_node);
  }
  return nvc;
}

static void gt_gff3_visitor_init(GtGFF3Visitor *gff3_visitor)
{
  gff3_visitor->version_string_shown = false;
  gff3_visitor->fasta_directive_shown = false;
  gff3_visitor->id_counter = gt_string_distri_new();
  gff3_visitor->feature_node_to_id_array =
    gt_hashmap_new(GT_HASH_DIRECT, NULL, (GtFree) gt_array_delete);
  gff3_visitor->feature_node_to_unique_id_str =
    gt_hashmap_new(GT_HASH_DIRECT, NULL, (GtFree) gt_str_delete);
  gff3_visitor->fasta_width = 0;
  gff3_visitor->used_ids = gt_cstr_table_new();
  /* XXX */
  gff3_visitor->retain_ids = getenv("GT_RETAINIDS") ? true : false;
  gff3_visitor->allow_nonunique_ids = false;
}

GtNodeVisitor* gt_gff3_visitor_new(GtFile *outfp)
{
  GtNodeVisitor *nv = gt_node_visitor_create(gt_gff3_visitor_class());
  GtGFF3Visitor *gff3_visitor = gff3_visitor_cast(nv);
  gt_gff3_visitor_init(gff3_visitor);
  gff3_visitor->outfp = gt_file_ref(outfp);
  gff3_visitor->outstr = NULL;
  return nv;
}

GtNodeVisitor* gt_gff3_visitor_new_to_str(GtStr *outstr)
{
  GtNodeVisitor *nv = gt_node_visitor_create(gt_gff3_visitor_class());
  GtGFF3Visitor *gff3_visitor = gff3_visitor_cast(nv);
  gt_gff3_visitor_init(gff3_visitor);
  gff3_visitor->outfp = NULL;
  gff3_visitor->outstr = gt_str_ref(outstr);
  return nv;
}

void gt_gff3_visitor_retain_id_attributes(GtGFF3Visitor *gff3_visitor)
{
  gt_assert(gff3_visitor);
  gff3_visitor->retain_ids = true;
}

void gt_gff3_visitor_allow_nonunique_ids(GtGFF3Visitor *gff3_visitor)
{
  gt_assert(gff3_visitor);
  gff3_visitor->allow_nonunique_ids = true;
}

void gt_gff3_visitor_set_fasta_width(GtGFF3Visitor *gff3_visitor,
                                     GtUword fasta_width)
{
  gt_assert(gff3_visitor);
  gff3_visitor->fasta_width = fasta_width;
}
