#include <compiler/fzl_parser.h>
#include <compiler/internals/parser.h>
#include <stdio.h>
#include <stdlib.h>

// Parse primary
fzl_node_t *pa_primary(fzl_parser_t *parser)
{
  if (!parser || !peek(parser))
    return NULL;

  if (is(parser, FZL_TOKTYPE_STR_LITERAL) ||
      is(parser, FZL_TOKTYPE_NUM_LITERAL) ||
      is(parser, FZL_TOKTYPE_BOOL_LITERAL) ||
      is(parser, FZL_TOKTYPE_NULL_LITERAL))
  {
    fzl_token_t *tok = consume(parser);
    return fzl_mknode(FZL_NODETYPE_LITERAL, tok);
  }
  else if (is(parser, FZL_TOKTYPE_STR_FORMAT_START))
  {
    consume(parser);

    size_t remainder     = 2;
    size_t count         = 0;
    fzl_node_t **entries = malloc(remainder * sizeof(fzl_node_t *));
    if (!entries)
    {
      snprintf(plast_err, sizeof(plast_err), "out of memory");
      return NULL;
    }

    while (peek(parser) && peek(parser)->type != FZL_TOKTYPE_STR_FORMAT_END)
    {
      if (is(parser, FZL_TOKTYPE_STR_FORMAT_END))
        break;

      if (remainder <= count)
      {
        remainder *= 2;
        fzl_node_t **newentries =
            realloc(entries, remainder * sizeof(fzl_node_t *));
        if (!newentries)
        {
          snprintf(plast_err, sizeof(plast_err), "out of memory");
          for (size_t i = 0; i < count; i++)
            fzl_freeast(entries[i]);

          free(entries);
          return NULL;
        }

        entries = newentries;
      }

      fzl_node_t *expr = pa_expression(parser);
      if (expr == NULL)
      {
        for (size_t i = 0; i < count; i++)
          fzl_freeast(entries[i]);

        free(entries);
        return NULL;
      }

      entries[count++] = expr;
    }

    fzl_token_t *end = consume(parser);
    if (end->type != FZL_TOKTYPE_STR_FORMAT_END)
    {
      snprintf(plast_err, sizeof(plast_err),
               "'%s':%zu:%zu => unterminated format string",
               last_known_tok->filename, last_known_tok->ln,
               last_known_tok->cn);

      for (size_t i = 0; i < count; i++)
        fzl_freeast(entries[i]);

      free(entries);
    }

    if (count < 1)
    {
      snprintf(plast_err, sizeof(plast_err),
               "'%s':%zu:%zu => do you really need empty format string?",
               last_known_tok->filename, last_known_tok->ln,
               last_known_tok->cn);

      for (size_t i = 0; i < count; i++)
        fzl_freeast(entries[i]);

      free(entries);
      return NULL;
    }

    fzl_node_t *node = fzl_mknode(FZL_NODETYPE_FMT_STRING, entries[0]->token);
    if (!node)
    {
      snprintf(plast_err, sizeof(plast_err), "out of memory");
      for (size_t i = 0; i < count; i++)
        fzl_freeast(entries[i]);

      free(entries);
      return NULL;
    }

    node->list.entries     = entries;
    node->list.entry_count = count;

    return node;
  }
  else if (is(parser, FZL_TOKTYPE_LPAREN))
  {
    consume(parser);
    fzl_node_t *node = pa_expression(parser);
    if (!is(parser, FZL_TOKTYPE_RPAREN))
    {
      snprintf(plast_err, sizeof(plast_err), "'%s': expected ')' at %ld:%ld",
               last_known_tok->filename, last_known_tok->ln,
               last_known_tok->cn);
      fzl_freeast(node);
      return NULL;
    }
    consume(parser);
    return node;
  }
  else if (is(parser, FZL_TOKTYPE_NAME))
  {
    fzl_token_t *name = consume(parser);
    if (!is(parser, FZL_TOKTYPE_NAME))
      return fzl_mknode(FZL_NODETYPE_IDENTIFIER, name);

    fzl_token_t *realname = consume(parser); // :D
    fzl_node_t *decl      = fzl_mknode(FZL_NODETYPE_DECLARATION, name);
    decl->var.type        = name;
    decl->var.identifier  = fzl_mknode(FZL_NODETYPE_IDENTIFIER, realname);
    return decl;
  }
  else if (is(parser, FZL_TOKTYPE_TYPE))
  {
    fzl_token_t *type = consume(parser);
    fzl_token_t *name = consume(parser);
    if (!name || name->type != FZL_TOKTYPE_NAME)
    {
      snprintf(plast_err, sizeof(plast_err),
               "'%s': expected name after type at %ld:%ld",
               last_known_tok->filename, last_known_tok->ln,
               last_known_tok->cn);
      return NULL;
    }

    fzl_node_t *decl     = fzl_mknode(FZL_NODETYPE_DECLARATION, type);
    decl->var.type       = type;
    decl->var.identifier = fzl_mknode(FZL_NODETYPE_IDENTIFIER, name);
    return decl;
  }

  if (!plast_err[0])
    snprintf(plast_err, sizeof(plast_err),
             "'%s': expected expression at %ld:%ld", last_known_tok->filename,
             last_known_tok->ln, last_known_tok->cn);
  return NULL;
}