#include <cmath>
#include <string>
#include <iostream>
#include <iomanip>
#include <stdint.h>
#include <stdint.h>

#include "ast.hpp"
#include "inspect.hpp"
#include "context.hpp"
#include "listize.hpp"
#include "color_maps.hpp"
#include "utf8/checked.h"

namespace Sass {

  Inspect::Inspect(Emitter emi)
  : Emitter(emi)
  { }
  Inspect::~Inspect() { }

  // statements
  void Inspect::operator()(Block* block)
  {
    if (!block->is_root()) {
      add_open_mapping(block);
      append_scope_opener();
    }
    if (output_style() == NESTED) indentation += block->tabs();
    for (size_t i = 0, L = block->length(); i < L; ++i) {
      (*block)[i]->perform(this);
    }
    if (output_style() == NESTED) indentation -= block->tabs();
    if (!block->is_root()) {
      append_scope_closer();
      add_close_mapping(block);
    }

  }

  void Inspect::operator()(Ruleset* ruleset)
  {
    ruleset->selector()->perform(this);
    ruleset->block()->perform(this);
  }

  void Inspect::operator()(Keyframe_Rule* rule)
  {
    if (rule->selector()) rule->selector()->perform(this);
    if (rule->block()) rule->block()->perform(this);
  }

  void Inspect::operator()(Propset* propset)
  {
    propset->property_fragment()->perform(this);
    append_colon_separator();
    propset->block()->perform(this);
  }

  void Inspect::operator()(Bubble* bubble)
  {
    append_indentation();
    append_token("::BUBBLE", bubble);
    append_scope_opener();
    bubble->node()->perform(this);
    append_scope_closer();
  }

  void Inspect::operator()(Media_Block* media_block)
  {
    append_indentation();
    append_token("@media", media_block);
    append_mandatory_space();
    in_media_block = true;
    media_block->media_queries()->perform(this);
    in_media_block = false;
    media_block->block()->perform(this);
  }

  void Inspect::operator()(Supports_Block* feature_block)
  {
    append_indentation();
    append_token("@supports", feature_block);
    append_mandatory_space();
    feature_block->condition()->perform(this);
    feature_block->block()->perform(this);
  }

  void Inspect::operator()(At_Root_Block* at_root_block)
  {
    append_indentation();
    append_token("@at-root ", at_root_block);
    append_mandatory_space();
    if(at_root_block->expression()) at_root_block->expression()->perform(this);
    at_root_block->block()->perform(this);
  }

  void Inspect::operator()(At_Rule* at_rule)
  {
    append_indentation();
    append_token(at_rule->keyword(), at_rule);
    if (at_rule->selector()) {
      append_mandatory_space();
      bool was_wrapped = in_wrapped;
      in_wrapped = true;
      at_rule->selector()->perform(this);
      in_wrapped = was_wrapped;
    }
    if (at_rule->value()) {
      append_mandatory_space();
      at_rule->value()->perform(this);
    }
    if (at_rule->block()) {
      at_rule->block()->perform(this);
    }
    else {
      append_delimiter();
    }
  }

  void Inspect::operator()(Declaration* dec)
  {
    if (dec->value()->concrete_type() == Expression::NULL_VAL) return;
    bool was_decl = in_declaration;
    in_declaration = true;
    if (output_style() == NESTED)
      indentation += dec->tabs();
    append_indentation();
    dec->property()->perform(this);
    append_colon_separator();

    if (dec->value()->concrete_type() == Expression::SELECTOR) {
      Listize listize(*ctx);
      dec->value()->perform(&listize)->perform(this);
    } else {
      dec->value()->perform(this);
    }

    if (dec->is_important()) {
      append_optional_space();
      append_string("!important");
    }
    append_delimiter();
    if (output_style() == NESTED)
      indentation -= dec->tabs();
    in_declaration = was_decl;
  }

  void Inspect::operator()(Assignment* assn)
  {
    append_token(assn->variable(), assn);
    append_colon_separator();
    assn->value()->perform(this);
    if (assn->is_default()) {
      append_optional_space();
      append_string("!default");
    }
    append_delimiter();
  }

  void Inspect::operator()(Import* import)
  {
    if (!import->urls().empty()) {
      append_token("@import", import);
      append_mandatory_space();

      if (String_Quoted* strq = dynamic_cast<String_Quoted*>(import->urls().front())) {
        strq->is_delayed(false);
      }

      import->urls().front()->perform(this);
      if (import->media_queries()) {
        append_mandatory_space();
        import->media_queries()->perform(this);
      }
      append_delimiter();
      for (size_t i = 1, S = import->urls().size(); i < S; ++i) {
        append_mandatory_linefeed();
        append_token("@import", import);
        append_mandatory_space();

        if (String_Quoted* strq = dynamic_cast<String_Quoted*>(import->urls()[i])) {
          strq->is_delayed(false);
        }

        import->urls()[i]->perform(this);
        if (import->media_queries()) {
          append_mandatory_space();
          import->media_queries()->perform(this);
        }
        append_delimiter();
      }
    }
  }

  void Inspect::operator()(Import_Stub* import)
  {
    append_indentation();
    append_token("@import", import);
    append_mandatory_space();
    append_string(import->file_name());
    append_delimiter();
  }

  void Inspect::operator()(Warning* warning)
  {
    append_indentation();
    append_token("@warn", warning);
    append_mandatory_space();
    warning->message()->perform(this);
    append_delimiter();
  }

  void Inspect::operator()(Error* error)
  {
    append_indentation();
    append_token("@error", error);
    append_mandatory_space();
    error->message()->perform(this);
    append_delimiter();
  }

  void Inspect::operator()(Debug* debug)
  {
    append_indentation();
    append_token("@debug", debug);
    append_mandatory_space();
    debug->value()->perform(this);
    append_delimiter();
  }

  void Inspect::operator()(Comment* comment)
  {
    in_comment = true;
    comment->text()->perform(this);
    in_comment = false;
  }

  void Inspect::operator()(If* cond)
  {
    append_indentation();
    append_token("@if", cond);
    append_mandatory_space();
    cond->predicate()->perform(this);
    cond->block()->perform(this);
    if (cond->alternative()) {
      append_optional_linefeed();
      append_indentation();
      append_string("else");
      cond->alternative()->perform(this);
    }
  }

  void Inspect::operator()(For* loop)
  {
    append_indentation();
    append_token("@for", loop);
    append_mandatory_space();
    append_string(loop->variable());
    append_string(" from ");
    loop->lower_bound()->perform(this);
    append_string(loop->is_inclusive() ? " through " : " to ");
    loop->upper_bound()->perform(this);
    loop->block()->perform(this);
  }

  void Inspect::operator()(Each* loop)
  {
    append_indentation();
    append_token("@each", loop);
    append_mandatory_space();
    append_string(loop->variables()[0]);
    for (size_t i = 1, L = loop->variables().size(); i < L; ++i) {
      append_comma_separator();
      append_string(loop->variables()[i]);
    }
    append_string(" in ");
    loop->list()->perform(this);
    loop->block()->perform(this);
  }

  void Inspect::operator()(While* loop)
  {
    append_indentation();
    append_token("@while", loop);
    append_mandatory_space();
    loop->predicate()->perform(this);
    loop->block()->perform(this);
  }

  void Inspect::operator()(Return* ret)
  {
    append_indentation();
    append_token("@return", ret);
    append_mandatory_space();
    ret->value()->perform(this);
    append_delimiter();
  }

  void Inspect::operator()(Extension* extend)
  {
    append_indentation();
    append_token("@extend", extend);
    append_mandatory_space();
    extend->selector()->perform(this);
    append_delimiter();
  }

  void Inspect::operator()(Definition* def)
  {
    append_indentation();
    if (def->type() == Definition::MIXIN) {
      append_token("@mixin", def);
      append_mandatory_space();
    } else {
      append_token("@function", def);
      append_mandatory_space();
    }
    append_string(def->name());
    def->parameters()->perform(this);
    def->block()->perform(this);
  }

  void Inspect::operator()(Mixin_Call* call)
  {
    append_indentation();
    append_token("@include", call);
    append_mandatory_space();
    append_string(call->name());
    if (call->arguments()) {
      call->arguments()->perform(this);
    }
    if (call->block()) {
      append_optional_space();
      call->block()->perform(this);
    }
    if (!call->block()) append_delimiter();
  }

  void Inspect::operator()(Content* content)
  {
    append_indentation();
    append_token("@content", content);
    append_delimiter();
  }

  void Inspect::operator()(Map* map)
  {
    if (map->empty()) return;
    if (map->is_invisible()) return;
    bool items_output = false;
    append_string("(");
    for (auto key : map->keys()) {
      if (items_output) append_comma_separator();
      key->perform(this);
      append_colon_separator();
      map->at(key)->perform(this);
      items_output = true;
    }
    append_string(")");
  }

  void Inspect::operator()(List* list)
  {
    std::string sep(list->separator() == SASS_SPACE ? " " : ",");
    if (output_style() != COMPRESSED && sep == ",") sep += " ";
    else if (in_media_block && sep != " ") sep += " "; // verified
    if (list->empty()) return;
    bool items_output = false;

    bool was_space_array = in_space_array;
    bool was_comma_array = in_comma_array;
    if (!in_declaration && (
        (list->separator() == SASS_SPACE && in_space_array) ||
        (list->separator() == SASS_COMMA && in_comma_array)
    )) {
      append_string("(");
    }

    if (list->separator() == SASS_SPACE) in_space_array = true;
    else if (list->separator() == SASS_COMMA) in_comma_array = true;

    for (size_t i = 0, L = list->size(); i < L; ++i) {
      Expression* list_item = (*list)[i];
      if (list_item->is_invisible()) {
        continue;
      }
      if (items_output) {
        append_string(sep);
      }
      if (items_output && sep != " ")
        append_optional_space();
      list_item->perform(this);
      items_output = true;
    }

    in_comma_array = was_comma_array;
    in_space_array = was_space_array;
    if (!in_declaration && (
        (list->separator() == SASS_SPACE && in_space_array) ||
        (list->separator() == SASS_COMMA && in_comma_array)
    )) {
      append_string(")");
    }

  }

  void Inspect::operator()(Binary_Expression* expr)
  {
    expr->left()->perform(this);
    switch (expr->type()) {
      case Sass_OP::AND: append_string(" and "); break;
      case Sass_OP::OR:  append_string(" or ");  break;
      case Sass_OP::EQ:  append_string(" == ");  break;
      case Sass_OP::NEQ: append_string(" != ");  break;
      case Sass_OP::GT:  append_string(" > ");   break;
      case Sass_OP::GTE: append_string(" >= ");  break;
      case Sass_OP::LT:  append_string(" < ");   break;
      case Sass_OP::LTE: append_string(" <= ");  break;
      case Sass_OP::ADD: append_string(" + ");   break;
      case Sass_OP::SUB: append_string(" - ");   break;
      case Sass_OP::MUL: append_string(" * ");   break;
      case Sass_OP::DIV: append_string(in_media_block ? " / " : "/"); break;
      case Sass_OP::MOD: append_string(" % ");   break;
      default: break; // shouldn't get here
    }
    expr->right()->perform(this);
  }

  void Inspect::operator()(Unary_Expression* expr)
  {
    if (expr->type() == Unary_Expression::PLUS) append_string("+");
    else                                        append_string("-");
    expr->operand()->perform(this);
  }

  void Inspect::operator()(Function_Call* call)
  {
    append_token(call->name(), call);
    call->arguments()->perform(this);
  }

  void Inspect::operator()(Function_Call_Schema* call)
  {
    call->name()->perform(this);
    call->arguments()->perform(this);
  }

  void Inspect::operator()(Variable* var)
  {
    append_token(var->name(), var);
  }

  void Inspect::operator()(Textual* txt)
  {
    append_token(txt->value(), txt);
  }

  void Inspect::operator()(Number* n)
  {
    // use values to_string facility
    bool compressed = ctx->output_style == COMPRESSED;
    std::string res = n->to_string(compressed, (int)ctx->precision);
    // output the final token
    append_token(res, n);
  }

  void Inspect::operator()(Color* c)
  {
    // use values to_string facility
    bool compressed = ctx->output_style == COMPRESSED;
	std::string res = c->to_string(compressed, (int)ctx->precision);
    // output the final token
    append_token(res, c);
  }

  void Inspect::operator()(Boolean* b)
  {
    // use values to_string facility
    bool compressed = ctx->output_style == COMPRESSED;
	std::string res = b->to_string(compressed, (int)ctx->precision);
    // output the final token
    append_token(res, b);
  }

  void Inspect::operator()(String_Schema* ss)
  {
    // Evaluation should turn these into String_Constants,
    // so this method is only for inspection purposes.
    for (size_t i = 0, L = ss->length(); i < L; ++i) {
      if ((*ss)[i]->is_interpolant()) append_string("#{");
      (*ss)[i]->perform(this);
      if ((*ss)[i]->is_interpolant()) append_string("}");
    }
  }

  void Inspect::operator()(String_Constant* s)
  {
    // get options from optional? context
    int precision = ctx ? (int)ctx->precision : 5;
    bool compressed = ctx ? ctx->output_style == COMPRESSED : false;
    // use values to_string facility
    std::string res(s->to_string(compressed, precision));
    // output the final token
    append_token(res, s);
  }

  void Inspect::operator()(String_Quoted* s)
  {
    // get options from optional? context
    int precision = ctx ? (int)ctx->precision : 5;
    bool compressed = ctx ? ctx->output_style == COMPRESSED : false;
    // use values to_string facility
    std::string res(s->to_string(compressed, precision));
    // output the final token
    append_token(res, s);
  }
  void Inspect::operator()(Supports_Operator* so)
  {

    if (so->needs_parens(so->left())) append_string("(");
    so->left()->perform(this);
    if (so->needs_parens(so->left())) append_string(")");

    if (so->operand() == Supports_Operator::AND) {
      append_mandatory_space();
      append_token("and", so);
      append_mandatory_space();
    } else if (so->operand() == Supports_Operator::OR) {
      append_mandatory_space();
      append_token("or", so);
      append_mandatory_space();
    }

    if (so->needs_parens(so->right())) append_string("(");
    so->right()->perform(this);
    if (so->needs_parens(so->right())) append_string(")");
  }

  void Inspect::operator()(Supports_Negation* sn)
  {
    append_token("not", sn);
    append_mandatory_space();
    if (sn->needs_parens(sn->condition())) append_string("(");
    sn->condition()->perform(this);
    if (sn->needs_parens(sn->condition())) append_string(")");
  }

  void Inspect::operator()(Supports_Declaration* sd)
  {
    append_string("(");
    sd->feature()->perform(this);
    append_string(": ");
    sd->value()->perform(this);
    append_string(")");
  }

  void Inspect::operator()(Supports_Interpolation* sd)
  {
    sd->value()->perform(this);
  }

  void Inspect::operator()(Media_Query* mq)
  {
    size_t i = 0;
    if (mq->media_type()) {
      if      (mq->is_negated())    append_string("not ");
      else if (mq->is_restricted()) append_string("only ");
      mq->media_type()->perform(this);
    }
    else {
      (*mq)[i++]->perform(this);
    }
    for (size_t L = mq->length(); i < L; ++i) {
      append_string(" and ");
      (*mq)[i]->perform(this);
    }
  }

  void Inspect::operator()(Media_Query_Expression* mqe)
  {
    if (mqe->is_interpolated()) {
      mqe->feature()->perform(this);
    }
    else {
      append_string("(");
      mqe->feature()->perform(this);
      if (mqe->value()) {
        append_string(": "); // verified
        mqe->value()->perform(this);
      }
      append_string(")");
    }
  }

  void Inspect::operator()(At_Root_Expression* ae)
  {
    if (ae->is_interpolated()) {
      ae->feature()->perform(this);
    }
    else {
      append_string("(");
      ae->feature()->perform(this);
      if (ae->value()) {
        append_colon_separator();
        ae->value()->perform(this);
      }
      append_string(")");
    }
  }

  void Inspect::operator()(Null* n)
  {
    // use values to_string facility
    bool compressed = ctx->output_style == COMPRESSED;
    std::string res = n->to_string(compressed, (int)ctx->precision);
    // output the final token
    append_token(res, n);
  }

  // parameters and arguments
  void Inspect::operator()(Parameter* p)
  {
    append_token(p->name(), p);
    if (p->default_value()) {
      append_colon_separator();
      p->default_value()->perform(this);
    }
    else if (p->is_rest_parameter()) {
      append_string("...");
    }
  }

  void Inspect::operator()(Parameters* p)
  {
    append_string("(");
    if (!p->empty()) {
      (*p)[0]->perform(this);
      for (size_t i = 1, L = p->length(); i < L; ++i) {
        append_comma_separator();
        (*p)[i]->perform(this);
      }
    }
    append_string(")");
  }

  void Inspect::operator()(Argument* a)
  {
    if (!a->name().empty()) {
      append_token(a->name(), a);
      append_colon_separator();
    }
    // Special case: argument nulls can be ignored
    if (a->value()->concrete_type() == Expression::NULL_VAL) {
      return;
    }
    if (a->value()->concrete_type() == Expression::STRING) {
      String_Constant* s = static_cast<String_Constant*>(a->value());
      s->perform(this);
    } else a->value()->perform(this);
    if (a->is_rest_argument()) {
      append_string("...");
    }
  }

  void Inspect::operator()(Arguments* a)
  {
    append_string("(");
    if (!a->empty()) {
      (*a)[0]->perform(this);
      for (size_t i = 1, L = a->length(); i < L; ++i) {
        append_string(", "); // verified
        // Sass Bug? append_comma_separator();
        (*a)[i]->perform(this);
      }
    }
    append_string(")");
  }

  void Inspect::operator()(Selector_Schema* s)
  {
    s->contents()->perform(this);
  }

  void Inspect::operator()(Parent_Selector* p)
  {
    append_string("&");
  }

  void Inspect::operator()(Selector_Placeholder* s)
  {
    append_token(s->name(), s);
    if (s->has_line_break()) append_optional_linefeed();
    if (s->has_line_break()) append_indentation();

  }

  void Inspect::operator()(Type_Selector* s)
  {
    append_token(s->ns_name(), s);
  }

  void Inspect::operator()(Selector_Qualifier* s)
  {
    append_token(s->ns_name(), s);
    if (s->has_line_break()) append_optional_linefeed();
    if (s->has_line_break()) append_indentation();
  }

  void Inspect::operator()(Attribute_Selector* s)
  {
    append_string("[");
    add_open_mapping(s);
    append_token(s->ns_name(), s);
    if (!s->matcher().empty()) {
      append_string(s->matcher());
      if (s->value()) {
        s->value()->perform(this);
      }
    }
    add_close_mapping(s);
    append_string("]");
  }

  void Inspect::operator()(Pseudo_Selector* s)
  {
    append_token(s->ns_name(), s);
    if (s->expression()) {
      append_string("(");
      s->expression()->perform(this);
      append_string(")");
    }
  }

  void Inspect::operator()(Wrapped_Selector* s)
  {
    bool was = in_wrapped;
    in_wrapped = true;
    append_token(s->name(), s);
    append_string("(");
    s->selector()->perform(this);
    append_string(")");
    in_wrapped = was;
  }

  void Inspect::operator()(Compound_Selector* s)
  {
    for (size_t i = 0, L = s->length(); i < L; ++i) {
      (*s)[i]->perform(this);
    }
    if (s->has_line_break()) {
      if (output_style() != COMPACT) {
        append_optional_linefeed();
      }
    }
  }

  void Inspect::operator()(Complex_Selector* c)
  {
    Compound_Selector*           head = c->head();
    Complex_Selector*            tail = c->tail();
    Complex_Selector::Combinator comb = c->combinator();

    if (c->has_line_feed()) {
      if (!(c->has_parent_ref())) {
        append_optional_linefeed();
        append_indentation();
      }
    }

    if (head && head->length() != 0) head->perform(this);
    bool is_empty = !head || head->length() == 0 || head->is_empty_reference();
    bool is_tail = head && !head->is_empty_reference() && tail;
    if (output_style() == COMPRESSED && comb != Complex_Selector::ANCESTOR_OF) scheduled_space = 0;

    switch (comb) {
      case Complex_Selector::ANCESTOR_OF:
        if (is_tail) append_mandatory_space();
      break;
      case Complex_Selector::PARENT_OF:
        append_optional_space();
        append_string(">");
        append_optional_space();
      break;
      case Complex_Selector::ADJACENT_TO:
        append_optional_space();
        append_string("+");
        append_optional_space();
      break;
      case Complex_Selector::REFERENCE:
        append_mandatory_space();
        append_string("/");
        c->reference()->perform(this);
        append_string("/");
        append_mandatory_space();
      break;
      case Complex_Selector::PRECEDES:
        if (is_empty) append_optional_space();
        else append_mandatory_space();
        append_string("~");
        if (tail) append_mandatory_space();
        else append_optional_space();
      break;
    }
    if (tail && comb != Complex_Selector::ANCESTOR_OF) {
      if (c->has_line_break()) append_optional_linefeed();
    }
    if (tail) tail->perform(this);
    if (!tail && c->has_line_break()) {
      if (output_style() == COMPACT) {
        append_mandatory_space();
      }
    }
  }

  void Inspect::operator()(Selector_List* g)
  {
    if (g->empty()) return;
    for (size_t i = 0, L = g->length(); i < L; ++i) {
      if (!in_wrapped && i == 0) append_indentation();
      if ((*g)[i] == 0) continue;
      (*g)[i]->perform(this);
      if (i < L - 1) {
        scheduled_space = 0;
        append_comma_separator();
      }
    }
  }

  void Inspect::fallback_impl(AST_Node* n)
  {
  }

}