/*

Copyright (C) 1996-2017 John W. Eaton

This file is part of Octave.

Octave is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.

Octave is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Octave; see the file COPYING.  If not, see
<http://www.gnu.org/licenses/>.

*/

#if defined (HAVE_CONFIG_H)
#  include "config.h"
#endif

#include <cctype>

#include <iostream>

#include "comment-list.h"
#include "error.h"
#include "ov-usr-fcn.h"
#include "pr-output.h"
#include "pt-all.h"

namespace octave
{
  void
  tree_print_code::visit_anon_fcn_handle (tree_anon_fcn_handle& afh)
  {
    indent ();

    print_parens (afh, "(");

    os << "@(";

    tree_parameter_list *param_list = afh.parameter_list ();

    if (param_list)
      param_list->accept (*this);

    os << ") ";

    print_fcn_handle_body (afh.expression ());

    print_parens (afh, ")");
  }

  void
  tree_print_code::visit_argument_list (tree_argument_list& lst)
  {
    tree_argument_list::iterator p = lst.begin ();

    while (p != lst.end ())
      {
        tree_expression *elt = *p++;

        if (elt)
          {
            elt->accept (*this);

            if (p != lst.end ())
              os << ", ";
          }
      }
  }

  void
  tree_print_code::visit_binary_expression (tree_binary_expression& expr)
  {
    indent ();

    print_parens (expr, "(");

    tree_expression *op1 = expr.lhs ();

    if (op1)
      op1->accept (*this);

    os << ' ' << expr.oper () << ' ';

    tree_expression *op2 = expr.rhs ();

    if (op2)
      op2->accept (*this);

    print_parens (expr, ")");
  }

  void
  tree_print_code::visit_break_command (tree_break_command&)
  {
    indent ();

    os << "break";
  }

  void
  tree_print_code::visit_colon_expression (tree_colon_expression& expr)
  {
    indent ();

    print_parens (expr, "(");

    tree_expression *op1 = expr.base ();

    if (op1)
      op1->accept (*this);

    // Stupid syntax.

    tree_expression *op3 = expr.increment ();

    if (op3)
      {
        os << ':';
        op3->accept (*this);
      }

    tree_expression *op2 = expr.limit ();

    if (op2)
      {
        os << ':';
        op2->accept (*this);
      }

    print_parens (expr, ")");
  }

  void
  tree_print_code::visit_continue_command (tree_continue_command&)
  {
    indent ();

    os << "continue";
  }

  void
  tree_print_code::visit_decl_command (tree_decl_command& cmd)
  {
    indent ();

    os << cmd.name () << ' ';

    tree_decl_init_list *init_list = cmd.initializer_list ();

    if (init_list)
      init_list->accept (*this);
  }

  void
  tree_print_code::visit_decl_init_list (tree_decl_init_list& lst)
  {
    tree_decl_init_list::iterator p = lst.begin ();

    while (p != lst.end ())
      {
        tree_decl_elt *elt = *p++;

        if (elt)
          {
            elt->accept (*this);

            if (p != lst.end ())
              os << ", ";
          }
      }
  }

  void
  tree_print_code::visit_decl_elt (tree_decl_elt& cmd)
  {
    tree_identifier *id = cmd.ident ();

    if (id)
      id->accept (*this);

    tree_expression *expr = cmd.expression ();

    if (expr)
      {
        os << " = ";

        expr->accept (*this);
      }
  }

  void
  tree_print_code::visit_simple_for_command (tree_simple_for_command& cmd)
  {
    print_comment_list (cmd.leading_comment ());

    indent ();

    os << (cmd.in_parallel () ? "parfor " : "for ");

    tree_expression *lhs = cmd.left_hand_side ();

    tree_expression *maxproc = cmd.maxproc_expr ();

    if (maxproc)
      os << '(';

    if (lhs)
      lhs->accept (*this);

    os << " = ";

    tree_expression *expr = cmd.control_expr ();

    if (expr)
      expr->accept (*this);

    if (maxproc)
      {
        os << ", ";
        maxproc->accept (*this);
        os << ')';
      }

    newline ();

    tree_statement_list *list = cmd.body ();

    if (list)
      {
        increment_indent_level ();

        list->accept (*this);

        decrement_indent_level ();
      }

    print_indented_comment (cmd.trailing_comment ());

    indent ();

    os << (cmd.in_parallel () ? "endparfor" : "endfor");
  }

  void
  tree_print_code::visit_complex_for_command (tree_complex_for_command& cmd)
  {
    print_comment_list (cmd.leading_comment ());

    indent ();

    os << "for [";
    nesting.push ('[');

    tree_argument_list *lhs = cmd.left_hand_side ();

    if (lhs)
      lhs->accept (*this);

    nesting.pop ();
    os << "] = ";

    tree_expression *expr = cmd.control_expr ();

    if (expr)
      expr->accept (*this);

    newline ();

    tree_statement_list *list = cmd.body ();

    if (list)
      {
        increment_indent_level ();

        list->accept (*this);

        decrement_indent_level ();
      }

    print_indented_comment (cmd.trailing_comment ());

    indent ();

    os << "endfor";
  }

  void
  tree_print_code::visit_octave_user_script (octave_user_script& fcn)
  {
    reset ();

    tree_statement_list *cmd_list = fcn.body ();

    if (cmd_list)
      cmd_list->accept (*this);
  }

  void
  tree_print_code::visit_octave_user_function (octave_user_function& fcn)
  {
    reset ();

    visit_octave_user_function_header (fcn);

    tree_statement_list *cmd_list = fcn.body ();

    if (cmd_list)
      {
        increment_indent_level ();

        cmd_list->accept (*this);

        // endfunction will decrement the indent level.
      }

    visit_octave_user_function_trailer (fcn);
  }

  void
  tree_print_code::visit_octave_user_function_header (octave_user_function& fcn)
  {
    comment_list *leading_comment = fcn.leading_comment ();

    if (leading_comment)
      {
        print_comment_list (leading_comment);
        newline ();
      }

    indent ();

    os << "function ";

    tree_parameter_list *ret_list = fcn.return_list ();

    if (ret_list)
      {
        bool takes_var_return = fcn.takes_var_return ();

        int len = ret_list->length ();

        if (len > 1 || takes_var_return)
          {
            os << '[';
            nesting.push ('[');
          }

        ret_list->accept (*this);

        if (takes_var_return)
          {
            if (len > 0)
              os << ", ";

            os << "varargout";
          }

        if (len > 1 || takes_var_return)
          {
            nesting.pop ();
            os << ']';
          }

        os << " = ";
      }

    std::string fcn_name = fcn.name ();

    os << (fcn_name.empty () ? std::string ("(empty)") : fcn_name) << ' ';

    tree_parameter_list *param_list = fcn.parameter_list ();

    if (param_list)
      {
        bool takes_varargs = fcn.takes_varargs ();

        int len = param_list->length ();

        if (len > 0 || takes_varargs)
          {
            os << '(';
            nesting.push ('(');
          }

        param_list->accept (*this);

        if (takes_varargs)
          {
            if (len > 0)
              os << ", ";

            os << "varargin";
          }

        if (len > 0 || takes_varargs)
          {
            nesting.pop ();
            os << ')';
            newline ();
          }
      }
    else
      {
        os << "()";
        newline ();
      }
  }

  void
  tree_print_code::visit_octave_user_function_trailer (octave_user_function& fcn)
  {
    print_indented_comment (fcn.trailing_comment ());

    newline ();
  }

  void
  tree_print_code::visit_function_def (tree_function_def& fdef)
  {
    indent ();

    octave_value fcn = fdef.function ();

    octave_function *f = fcn.function_value ();

    if (f)
      f->accept (*this);
  }

  void
  tree_print_code::visit_identifier (tree_identifier& id)
  {
    indent ();

    print_parens (id, "(");

    std::string nm = id.name ();
    os << (nm.empty () ? std::string ("(empty)") : nm);

    print_parens (id, ")");
  }

  void
  tree_print_code::visit_if_clause (tree_if_clause& cmd)
  {
    tree_expression *expr = cmd.condition ();

    if (expr)
      expr->accept (*this);

    newline ();

    tree_statement_list *list = cmd.commands ();

    if (list)
      {
        increment_indent_level ();

        list->accept (*this);

        decrement_indent_level ();
      }
  }

  void
  tree_print_code::visit_if_command (tree_if_command& cmd)
  {
    print_comment_list (cmd.leading_comment ());

    indent ();

    os << "if ";

    tree_if_command_list *list = cmd.cmd_list ();

    if (list)
      list->accept (*this);

    print_indented_comment (cmd.trailing_comment ());

    indent ();

    os << "endif";
  }

  void
  tree_print_code::visit_if_command_list (tree_if_command_list& lst)
  {
    tree_if_command_list::iterator p = lst.begin ();

    bool first_elt = true;

    while (p != lst.end ())
      {
        tree_if_clause *elt = *p++;

        if (elt)
          {
            if (! first_elt)
              {
                print_indented_comment (elt->leading_comment ());

                indent ();

                if (elt->is_else_clause ())
                  os << "else";
                else
                  os << "elseif ";
              }

            elt->accept (*this);
          }

        first_elt = false;
      }
  }

  void
  tree_print_code::visit_index_expression (tree_index_expression& expr)
  {
    indent ();

    print_parens (expr, "(");

    tree_expression *e = expr.expression ();

    if (e)
      e->accept (*this);

    std::list<tree_argument_list *> arg_lists = expr.arg_lists ();
    std::string type_tags = expr.type_tags ();
    std::list<string_vector> arg_names = expr.arg_names ();

    int n = type_tags.length ();

    std::list<tree_argument_list *>::iterator p_arg_lists = arg_lists.begin ();
    std::list<string_vector>::iterator p_arg_names = arg_names.begin ();

    for (int i = 0; i < n; i++)
      {
        switch (type_tags[i])
          {
          case '(':
            {
              char nc = nesting.top ();
              if ((nc == '[' || nc == '{') && expr.paren_count () == 0)
                os << '(';
              else
                os << " (";
              nesting.push ('(');

              tree_argument_list *l = *p_arg_lists;
              if (l)
                l->accept (*this);

              nesting.pop ();
              os << ')';
            }
            break;

          case '{':
            {
              char nc = nesting.top ();
              if ((nc == '[' || nc == '{') && expr.paren_count () == 0)
                os << '{';
              else
                os << " {";
              // We only care about whitespace inside [] and {} when we
              // are defining matrix and cell objects, not when indexing.
              nesting.push ('(');

              tree_argument_list *l = *p_arg_lists;
              if (l)
                l->accept (*this);

              nesting.pop ();
              os << '}';
            }
            break;

          case '.':
            {
              string_vector nm = *p_arg_names;
              assert (nm.numel () == 1);
              os << '.' << nm(0);
            }
            break;

          default:
            panic_impossible ();
          }

        p_arg_lists++;
        p_arg_names++;
      }

    print_parens (expr, ")");
  }

  void
  tree_print_code::visit_matrix (tree_matrix& lst)
  {
    indent ();

    print_parens (lst, "(");

    os << '[';
    nesting.push ('[');

    tree_matrix::iterator p = lst.begin ();

    while (p != lst.end ())
      {
        tree_argument_list *elt = *p++;

        if (elt)
          {
            elt->accept (*this);

            if (p != lst.end ())
              os << "; ";
          }
      }

    nesting.pop ();
    os << ']';

    print_parens (lst, ")");
  }

  void
  tree_print_code::visit_cell (tree_cell& lst)
  {
    indent ();

    print_parens (lst, "(");

    os << '{';
    nesting.push ('{');

    tree_cell::iterator p = lst.begin ();

    while (p != lst.end ())
      {
        tree_argument_list *elt = *p++;

        if (elt)
          {
            elt->accept (*this);

            if (p != lst.end ())
              os << "; ";
          }
      }

    nesting.pop ();
    os << '}';

    print_parens (lst, ")");
  }

  void
  tree_print_code::visit_multi_assignment (tree_multi_assignment& expr)
  {
    indent ();

    print_parens (expr, "(");

    tree_argument_list *lhs = expr.left_hand_side ();

    if (lhs)
      {
        int len = lhs->length ();

        if (len > 1)
          {
            os << '[';
            nesting.push ('[');
          }

        lhs->accept (*this);

        if (len > 1)
          {
            nesting.pop ();
            os << ']';
          }
      }

    os << ' ' << expr.oper () << ' ';

    tree_expression *rhs = expr.right_hand_side ();

    if (rhs)
      rhs->accept (*this);

    print_parens (expr, ")");
  }

  void
  tree_print_code::visit_no_op_command (tree_no_op_command& cmd)
  {
    if (cmd.is_end_of_fcn_or_script () && curr_print_indent_level > 1)
      decrement_indent_level ();

    indent ();

    os << cmd.original_command ();
  }

  void
  tree_print_code::visit_constant (tree_constant& val)
  {
    indent ();

    print_parens (val, "(");

    val.print_raw (os, true, print_original_text);

    print_parens (val, ")");
  }

  void
  tree_print_code::visit_fcn_handle (tree_fcn_handle& fh)
  {
    indent ();

    print_parens (fh, "(");

    fh.print_raw (os, true, print_original_text);

    print_parens (fh, ")");
  }

  void
  tree_print_code::visit_funcall (tree_funcall& fc)
  {
    indent ();

    print_parens (fc, "(");

    fc.print_raw (os, true, print_original_text);

    print_parens (fc, ")");
  }

  void
  tree_print_code::visit_parameter_list (tree_parameter_list& lst)
  {
    tree_parameter_list::iterator p = lst.begin ();

    while (p != lst.end ())
      {
        tree_decl_elt *elt = *p++;

        if (elt)
          {
            elt->accept (*this);

            if (p != lst.end ())
              os << ", ";
          }
      }
  }

  void
  tree_print_code::visit_postfix_expression (tree_postfix_expression& expr)
  {
    indent ();

    print_parens (expr, "(");

    tree_expression *e = expr.operand ();

    if (e)
      e->accept (*this);

    os << expr.oper ();

    print_parens (expr, ")");
  }

  void
  tree_print_code::visit_prefix_expression (tree_prefix_expression& expr)
  {
    indent ();

    print_parens (expr, "(");

    os << expr.oper ();

    tree_expression *e = expr.operand ();

    if (e)
      e->accept (*this);

    print_parens (expr, ")");
  }

  void
  tree_print_code::visit_return_command (tree_return_command&)
  {
    indent ();

    os << "return";
  }

  void
  tree_print_code::visit_return_list (tree_return_list& lst)
  {
    tree_return_list::iterator p = lst.begin ();

    while (p != lst.end ())
      {
        tree_index_expression *elt = *p++;

        if (elt)
          {
            elt->accept (*this);

            if (p != lst.end ())
              os << ", ";
          }
      }
  }

  void
  tree_print_code::visit_simple_assignment (tree_simple_assignment& expr)
  {
    indent ();

    print_parens (expr, "(");

    tree_expression *lhs = expr.left_hand_side ();

    if (lhs)
      lhs->accept (*this);

    os << ' ' << expr.oper () << ' ';

    tree_expression *rhs = expr.right_hand_side ();

    if (rhs)
      rhs->accept (*this);

    print_parens (expr, ")");
  }

  void
  tree_print_code::visit_statement (tree_statement& stmt)
  {
    print_comment_list (stmt.comment_text ());

    tree_command *cmd = stmt.command ();

    if (cmd)
      {
        cmd->accept (*this);

        newline ();
      }
    else
      {
        tree_expression *expr = stmt.expression ();

        if (expr)
          {
            expr->accept (*this);

            if (! stmt.print_result ())
              {
                os << ';';
                newline (" ");
              }
            else
              newline ();
          }
      }
  }

  void
  tree_print_code::visit_statement_list (tree_statement_list& lst)
  {
    for (tree_statement *elt : lst)
      {
        if (elt)
          elt->accept (*this);
      }
  }

  void
  tree_print_code::visit_switch_case (tree_switch_case& cs)
  {
    print_comment_list (cs.leading_comment ());

    indent ();

    if (cs.is_default_case ())
      os << "otherwise";
    else
      os << "case ";

    tree_expression *label = cs.case_label ();

    if (label)
      label->accept (*this);

    newline ();

    tree_statement_list *list = cs.commands ();

    if (list)
      {
        increment_indent_level ();

        list->accept (*this);

        newline ();

        decrement_indent_level ();
      }
  }

  void
  tree_print_code::visit_switch_case_list (tree_switch_case_list& lst)
  {
    tree_switch_case_list::iterator p = lst.begin ();

    while (p != lst.end ())
      {
        tree_switch_case *elt = *p++;

        if (elt)
          elt->accept (*this);
      }
  }

  void
  tree_print_code::visit_switch_command (tree_switch_command& cmd)
  {
    print_comment_list (cmd.leading_comment ());

    indent ();

    os << "switch ";

    tree_expression *expr = cmd.switch_value ();

    if (expr)
      expr->accept (*this);

    newline ();

    tree_switch_case_list *list = cmd.case_list ();

    if (list)
      {
        increment_indent_level ();

        list->accept (*this);

        decrement_indent_level ();
      }

    print_indented_comment (cmd.leading_comment ());

    indent ();

    os << "endswitch";
  }

  void
  tree_print_code::visit_try_catch_command (tree_try_catch_command& cmd)
  {
    print_comment_list (cmd.leading_comment ());

    indent ();

    os << "try";

    newline ();

    tree_statement_list *try_code = cmd.body ();
    tree_identifier *expr_id = cmd.identifier ();

    if (try_code)
      {
        increment_indent_level ();

        try_code->accept (*this);

        decrement_indent_level ();
      }

    print_indented_comment (cmd.middle_comment ());

    indent ();

    os << "catch";

    if (expr_id)
      {
        os << ' ';
        expr_id->accept (*this);
      }

    newline ();

    tree_statement_list *catch_code = cmd.cleanup ();

    if (catch_code)
      {
        increment_indent_level ();

        catch_code->accept (*this);

        decrement_indent_level ();
      }

    print_indented_comment (cmd.trailing_comment ());

    indent ();

    os << "end_try_catch";
  }

  void
  tree_print_code::visit_unwind_protect_command (tree_unwind_protect_command& cmd)
  {
    print_comment_list (cmd.leading_comment ());

    indent ();

    os << "unwind_protect";

    newline ();

    tree_statement_list *unwind_protect_code = cmd.body ();

    if (unwind_protect_code)
      {
        increment_indent_level ();

        unwind_protect_code->accept (*this);

        decrement_indent_level ();
      }

    print_indented_comment (cmd.middle_comment ());

    indent ();

    os << "unwind_protect_cleanup";

    newline ();

    tree_statement_list *cleanup_code = cmd.cleanup ();

    if (cleanup_code)
      {
        increment_indent_level ();

        cleanup_code->accept (*this);

        decrement_indent_level ();
      }

    print_indented_comment (cmd.trailing_comment ());

    indent ();

    os << "end_unwind_protect";
  }

  void
  tree_print_code::visit_while_command (tree_while_command& cmd)
  {
    print_comment_list (cmd.leading_comment ());

    indent ();

    os << "while ";

    tree_expression *expr = cmd.condition ();

    if (expr)
      expr->accept (*this);

    newline ();

    tree_statement_list *list = cmd.body ();

    if (list)
      {
        increment_indent_level ();

        list->accept (*this);

        decrement_indent_level ();
      }

    print_indented_comment (cmd.trailing_comment ());

    indent ();

    os << "endwhile";
  }

  void
  tree_print_code::visit_do_until_command (tree_do_until_command& cmd)
  {
    print_comment_list (cmd.leading_comment ());

    indent ();

    os << "do";

    newline ();

    tree_statement_list *list = cmd.body ();

    if (list)
      {
        increment_indent_level ();

        list->accept (*this);

        decrement_indent_level ();
      }

    print_indented_comment (cmd.trailing_comment ());

    indent ();

    os << "until ";

    tree_expression *expr = cmd.condition ();

    if (expr)
      expr->accept (*this);

    newline ();
  }

  void
  tree_print_code::print_fcn_handle_body (tree_expression *e)
  {
    if (e)
      {
        suppress_newlines++;
        e->accept (*this);
        suppress_newlines--;
      }
  }

  // Each print_code() function should call this before printing anything.

  void
  tree_print_code::indent (void)
  {
    assert (curr_print_indent_level >= 0);

    if (beginning_of_line)
      {
        os << prefix;

        os << std::string (curr_print_indent_level, ' ');

        beginning_of_line = false;
      }
  }

  // All print_code() functions should use this to print new lines.

  void
  tree_print_code::newline (const char *alt_txt)
  {
    if (suppress_newlines)
      os << alt_txt;
    else
      {
        // Print prefix for blank lines.
        indent ();

        os << "\n";

        beginning_of_line = true;
      }
  }

  // For ressetting print_code state.

  void
  tree_print_code::reset (void)
  {
    beginning_of_line = true;
    curr_print_indent_level = 0;
    while (nesting.top () != 'n')
      nesting.pop ();
  }

  void
  tree_print_code::print_parens (const tree_expression& expr, const char *txt)
  {
    int n = expr.paren_count ();

    for (int i = 0; i < n; i++)
      os << txt;
  }

  void
  tree_print_code::print_comment_elt (const comment_elt& elt)
  {
    bool printed_something = false;

    bool prev_char_was_newline = false;

    std::string comment = elt.text ();

    size_t len = comment.length ();

    size_t i = 0;

    while (i < len && comment[i++] == '\n')
      ; // Skip leading new lines.
    i--;

    while (i < len)
      {
        char c = comment[i++];

        if (c == '\n')
          {
            if (prev_char_was_newline)
              {
                printed_something = true;

                indent ();

                os << "##";
              }

            newline ();

            prev_char_was_newline = true;
          }
        else
          {
            if (beginning_of_line)
              {
                printed_something = true;

                indent ();

                os << "##";

                if (! (isspace (c) || c == '!'))
                  os << ' ';
              }

            os << static_cast<char> (c);

            prev_char_was_newline = false;
          }
      }

    if (printed_something && ! beginning_of_line)
      newline ();
  }

  void
  tree_print_code::print_comment_list (comment_list *comment_list)
  {
    if (comment_list)
      {
        comment_list::iterator p = comment_list->begin ();

        while (p != comment_list->end ())
          {
            comment_elt elt = *p++;

            print_comment_elt (elt);

            if (p != comment_list->end ())
              newline ();
          }
      }
  }

  void
  tree_print_code::print_indented_comment (comment_list *comment_list)
  {
    increment_indent_level ();

    print_comment_list (comment_list);

    decrement_indent_level ();
  }
}