/*
  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.
*/

#define _POSIX_C_SOURCE 200809L /* for posix_fadvise */

#include "world.h"

#include "cursor.h"
#include "namespaces.h"
#include "node.h"
#include "serd_config.h"

#if USE_FILENO && USE_ISATTY
#  include <unistd.h>
#endif

#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define BLANK_CHARS 12

static inline int
level_color(const SerdLogLevel level)
{
  switch (level) {
  case SERD_LOG_LEVEL_EMERG:
  case SERD_LOG_LEVEL_ALERT:
  case SERD_LOG_LEVEL_CRIT:
  case SERD_LOG_LEVEL_ERR:
    return 31; // Red
  case SERD_LOG_LEVEL_WARNING:
    return 33; // Yellow
  case SERD_LOG_LEVEL_NOTICE:
  case SERD_LOG_LEVEL_INFO:
  case SERD_LOG_LEVEL_DEBUG:
    break;
  }

  return 1; // White
}

static inline bool
terminal_supports_color(void)
{
  const char* const term = getenv("TERM");
  return !getenv("NO_COLOR") && term && strstr(term, "color");
}

static inline bool
serd_ansi_start(FILE* stream, int color, bool bold)
{
#if USE_FILENO && USE_ISATTY
  if (isatty(fileno(stream)) && terminal_supports_color()) {
    return fprintf(stream, bold ? "\033[0;%d;1m" : "\033[0;%dm", color);
  }
#endif

  return 0;
}

static inline void
serd_ansi_reset(FILE* stream)
{
#if USE_FILENO && USE_ISATTY
  if (isatty(fileno(stream)) && terminal_supports_color()) {
    fprintf(stream, "\033[0m");
    fflush(stream);
  }
#endif
}

static const char* const log_level_strings[] = {"emergengy",
                                                "alert",
                                                "critical",
                                                "error",
                                                "warning",
                                                "note",
                                                "info",
                                                "debug"};

SERD_CONST_FUNC
SerdStatus
serd_quiet_error_func(void* handle, const SerdLogEntry* entry)
{
  (void)handle;
  (void)entry;
  return SERD_SUCCESS;
}

static const char*
get_log_field(const SerdLogField* const fields,
              const size_t              n_fields,
              const char* const         key)
{
  for (size_t i = 0; i < n_fields; ++i) {
    if (!strcmp(fields[i].key, key)) {
      return fields[i].value;
    }
  }

  return NULL;
}

const char*
serd_log_entry_get_field(const SerdLogEntry* const entry, const char* const key)
{
  return get_log_field(entry->fields, entry->n_fields, key);
}

SerdStatus
serd_world_vlogf(const SerdWorld*    world,
                 const char*         domain,
                 SerdLogLevel        level,
                 const size_t        n_fields,
                 const SerdLogField* fields,
                 const char*         fmt,
                 va_list             args)
{
  // Copy args (which may be an array) to portably get a pointer
  va_list ap;
  va_copy(ap, args);

  const SerdLogEntry e  = {domain, fields, fmt, &ap, level, n_fields};
  SerdStatus         st = SERD_SUCCESS;

  if (world->log_func) {
    st = world->log_func(world->log_handle, &e);
  } else {
    // Print input file and position prefix if available
    const char* const file = serd_log_entry_get_field(&e, "SERD_FILE");
    const char* const line = serd_log_entry_get_field(&e, "SERD_LINE");
    const char* const col  = serd_log_entry_get_field(&e, "SERD_COL");
    if (file && line && col) {
      serd_ansi_start(stderr, 1, true);
      fprintf(stderr, "%s:%s:%s: ", file, line, col);
      serd_ansi_reset(stderr);
    }

    // Print GCC-style level prefix (error, warning, etc)
    serd_ansi_start(stderr, level_color(level), true);
    fprintf(stderr, "%s: ", log_level_strings[level]);
    serd_ansi_reset(stderr);

    // Using a copy isn't necessary here, but it avoids a clang-tidy bug
    vfprintf(stderr, fmt, ap);
  }

  va_end(ap);
  return st;
}

SerdStatus
serd_world_logf(const SerdWorld*    world,
                const char*         domain,
                SerdLogLevel        level,
                const size_t        n_fields,
                const SerdLogField* fields,
                const char*         fmt,
                ...)
{
  va_list args;
  va_start(args, fmt);

  const SerdStatus st =
    serd_world_vlogf(world, domain, level, n_fields, fields, fmt, args);

  va_end(args);
  return st;
}

SerdStatus
serd_world_vlogf_internal(const SerdWorld*  world,
                          SerdStatus        st,
                          SerdLogLevel      level,
                          const SerdCursor* cursor,
                          const char*       fmt,
                          va_list           args)
{
  char st_str[12];
  snprintf(st_str, sizeof(st_str), "%u", st);
  if (cursor) {
    const char* file = serd_node_string(serd_cursor_name(cursor));

    char line[24];
    snprintf(line, sizeof(line), "%u", serd_cursor_line(cursor));

    char col[24];
    snprintf(col, sizeof(col), "%u", serd_cursor_column(cursor));

    const SerdLogField fields[] = {{"SERD_STATUS", st_str},
                                   {"SERD_FILE", file},
                                   {"SERD_LINE", line},
                                   {"SERD_COL", col}};

    serd_world_vlogf(world, "serd", level, 4, fields, fmt, args);
  } else {
    const SerdLogField fields[] = {{"SERD_STATUS", st_str}};
    serd_world_vlogf(world, "serd", level, 1, fields, fmt, args);
  }

  return st;
}

SerdStatus
serd_world_logf_internal(const SerdWorld*  world,
                         SerdStatus        st,
                         SerdLogLevel      level,
                         const SerdCursor* cursor,
                         const char*       fmt,
                         ...)
{
  va_list args;
  va_start(args, fmt);
  serd_world_vlogf_internal(world, st, level, cursor, fmt, args);
  va_end(args);
  return st;
}

SerdWorld*
serd_world_new(void)
{
  SerdWorld* world = (SerdWorld*)calloc(1, sizeof(SerdWorld));
  SerdNodes* nodes = serd_nodes_new();

  const SerdStringView rdf_first   = SERD_STATIC_STRING(NS_RDF "first");
  const SerdStringView rdf_nil     = SERD_STATIC_STRING(NS_RDF "nil");
  const SerdStringView rdf_rest    = SERD_STATIC_STRING(NS_RDF "rest");
  const SerdStringView rdf_type    = SERD_STATIC_STRING(NS_RDF "type");
  const SerdStringView xsd_boolean = SERD_STATIC_STRING(NS_XSD "boolean");
  const SerdStringView xsd_decimal = SERD_STATIC_STRING(NS_XSD "decimal");
  const SerdStringView xsd_integer = SERD_STATIC_STRING(NS_XSD "integer");
  const SerdStringView xsd_long    = SERD_STATIC_STRING(NS_XSD "long");

  world->rdf_first   = serd_nodes_manage(nodes, serd_new_uri(rdf_first));
  world->rdf_nil     = serd_nodes_manage(nodes, serd_new_uri(rdf_nil));
  world->rdf_rest    = serd_nodes_manage(nodes, serd_new_uri(rdf_rest));
  world->rdf_type    = serd_nodes_manage(nodes, serd_new_uri(rdf_type));
  world->xsd_boolean = serd_nodes_manage(nodes, serd_new_uri(xsd_boolean));
  world->xsd_decimal = serd_nodes_manage(nodes, serd_new_uri(xsd_decimal));
  world->xsd_integer = serd_nodes_manage(nodes, serd_new_uri(xsd_integer));
  world->xsd_long    = serd_nodes_manage(nodes, serd_new_uri(xsd_long));
  world->blank_node  = serd_new_blank(SERD_STATIC_STRING("b00000000000"));
  world->nodes       = nodes;

  return world;
}

void
serd_world_free(SerdWorld* world)
{
  if (world) {
    serd_node_free(world->blank_node);
    serd_nodes_free(world->nodes);
    free(world);
  }
}

SerdNodes*
serd_world_nodes(SerdWorld* world)
{
  return world->nodes;
}

const SerdNode*
serd_world_get_blank(SerdWorld* world)
{
  char* buf = serd_node_buffer(world->blank_node);
  memset(buf, 0, BLANK_CHARS + 1);

  world->blank_node->n_bytes =
    (size_t)snprintf(buf, BLANK_CHARS + 1, "b%u", ++world->next_blank_id);

  return world->blank_node;
}

void
serd_world_set_log_func(SerdWorld* world, SerdLogFunc log_func, void* handle)
{
  world->log_func   = log_func;
  world->log_handle = handle;
}