require "isodoc"
require "fileutils"

module IsoDoc
  module ITU
    class Xref < IsoDoc::Xref
      def initialize(lang, script, klass, labels, options)
        super
        @hierarchical_assets = options[:hierarchical_assets]
      end

      def annex_name_lbl(clause, num)
        lbl = clause["obligation"] == "informative" ? 
          @labels["appendix"] : @labels["annex"]
        l10n("<strong>#{lbl} #{num}</strong>")
      end

      def annex_names(clause, num)
        lbl = clause["obligation"] == "informative" ? 
          @labels["appendix"] : @labels["annex"]
        @anchors[clause["id"]] =
          { label: annex_name_lbl(clause, num), type: "clause",
            xref: "#{lbl} #{num}", level: 1 }
        if a = single_annex_special_section(clause)
          annex_names1(a, "#{num}", 1)
        else
          clause.xpath(ns("./clause | ./references | ./terms | ./definitions")).
            each_with_index do |c, i|
            annex_names1(c, "#{num}.#{i + 1}", 2)
          end
        end
        hierarchical_asset_names(clause, num)
      end

      def back_anchor_names(docxml)
        super
        if annexid =
            docxml&.at(ns("//bibdata/ext/structuredidentifier/annexid"))&.text
          docxml.xpath(ns("//annex")).each { |c| annex_names(c, annexid) }
        else
          docxml.xpath(ns("//annex[@obligation = 'informative']"))
            .each_with_index do |c, i|
            annex_names(c, RomanNumerals.to_roman(i + 1))
          end
          docxml.xpath(ns("//annex[not(@obligation = 'informative')]"))
            .each_with_index do |c, i|
            annex_names(c, (65 + i + (i > 7 ? 1 : 0)).chr.to_s)
          end
        end
      end

      def annex_names1(clause, num, level)
        @anchors[clause["id"]] =
          { label: num, xref: "#{@labels["annex_subclause"]} #{num}",
            level: level, type: "clause" }
        clause.xpath(ns("./clause | ./references | ./terms | ./definitions"))
          .each_with_index do |c, i|
          annex_names1(c, "#{num}.#{i + 1}", level + 1)
        end
      end

      def initial_anchor_names(d)
        d.xpath(ns("//boilerplate//clause")).each { |c| preface_names(c) }
        d.xpath("//xmlns:preface/child::*").each { |c| preface_names(c) }
        @hierarchical_assets ?
          hierarchical_asset_names(d.xpath("//xmlns:preface/child::*"), 
                                   "Preface") :
                                  sequential_asset_names(d.xpath("//xmlns:preface/child::*"))
        n = section_names(d.at(ns("//clause[@type = 'scope']")), 0, 1)
        n = section_names(d.at(ns(@klass.norm_ref_xpath)), n, 1)
        n = section_names(d.at(ns("//sections/terms | "\
                                  "//sections/clause[descendant::terms]")), n, 1)
        n = section_names(d.at(ns("//sections/definitions")), n, 1)
        clause_names(d, n)
        middle_section_asset_names(d)
        termnote_anchor_names(d)
        termexample_anchor_names(d)
      end

      def middle_sections
        "//clause[@type = 'scope'] | "\
          "//foreword | //introduction | //acknowledgements | "\
          " #{@klass.norm_ref_xpath} | "\
          "//sections/terms | //preface/clause | "\
          "//sections/definitions | //clause[parent::sections]"
      end

      def middle_section_asset_names(d)
        return super unless @hierarchical_assets
        d.xpath(ns(middle_sections)).each do |c|
          hierarchical_asset_names(c, @anchors[c["id"]][:label])
        end
      end

      def sequential_figure_names(clause)
        c = IsoDoc::XrefGen::Counter.new
        j = 0
        clause.xpath(ns(".//figure | .//sourcecode[not(ancestor::example)]")).each do |t|
          if t.parent.name == "figure" then j += 1
          else
            j = 0
            c.increment(t)
          end
          label = c.print + (j.zero? ? "" : "#{hierfigsep}#{(96 + j).chr.to_s}")
          next if t["id"].nil? || t["id"].empty?
          @anchors[t["id"]] =
            anchor_struct(label, nil, @labels["figure"], "figure", t["unnumbered"])
        end
      end

      def hierarchical_figure_names(clause, num)
        c = IsoDoc::XrefGen::Counter.new
        j = 0
        clause.xpath(ns(".//figure | "\
                        ".//sourcecode[not(ancestor::example)]")).each do |t|
          if t.parent.name == "figure" then j += 1
          else
            j = 0
            c.increment(t)
          end
          label = "#{num}#{hiersep}#{c.print}" +
            (j.zero? ? "" : "#{hierfigsep}#{(96 + j).chr.to_s}")
          next if t["id"].nil? || t["id"].empty?
          @anchors[t["id"]] = 
            anchor_struct(label, nil, @labels["figure"], "figure",
                          t["unnumbered"])
        end
      end

      def sequential_formula_names(clause)
        clause&.first&.xpath(ns(middle_sections))&.each do |c|
          if c["id"] && @anchors[c["id"]]
            hierarchical_formula_names(c, @anchors[c["id"]][:label] ||
                                       @anchors[c["id"]][:xref] || "???")
          else
            hierarchical_formula_names(c, "???")
          end
        end
      end

      def hierarchical_formula_names(clause, num)
        c = IsoDoc::XrefGen::Counter.new
        clause.xpath(ns(".//formula")).each do |t|
          next if t["id"].nil? || t["id"].empty?
          @anchors[t["id"]] = anchor_struct(
            "#{num}-#{c.increment(t).print}", nil,
            t["inequality"] ? @labels["inequality"] : @labels["formula"],
            "formula", t["unnumbered"])
        end
      end

      def reference_names(ref)
        super
        @anchors[ref["id"]] = 
          { xref: @anchors[ref["id"]][:xref].sub(/^\[/, '').sub(/\]$/, '') }
      end

      def termnote_anchor_names(docxml)
        docxml.xpath(ns("//term[descendant::termnote]")).each do |t|
          c = IsoDoc::XrefGen::Counter.new
          notes = t.xpath(ns(".//termnote"))
          notes.each do |n|
            return if n["id"].nil? || n["id"].empty?
            idx = notes.size == 1 ? "" : " #{c.increment(n).print}"
            @anchors[n["id"]] = 
              { label: termnote_label(idx).strip, type: "termnote",
              xref: l10n("#{anchor(t['id'], :xref)}, "\
                         "#{@labels["note_xref"]} #{c.print}") }

          end
        end
      end
    end
  end
end