# frozen_string_literal: true

require_relative '../../../../lib/declare_schema/model/index_definition'

# Beware: It looks out that Rails' sqlite3 driver has a bug in retrieving indexes.
# In sqlite3/schema_statements, it skips over any index that starts with sqlite_:
#    next if row["name"].starts_with?("sqlite_")
# but this will skip over any indexes created to support "unique" column constraints.
# This gem provides an explicit name for all indexes so it shouldn't be affected by the bug...
# unless you manually create any Sqlite tables with UNIQUE constraints.

RSpec.describe DeclareSchema::Model::IndexDefinition do
  let(:model_class) { IndexDefinitionTestModel }

  context 'Using declare_schema' do
    before do
      load File.expand_path('../prepare_testapp.rb', __dir__)

      class IndexDefinitionTestModel < ActiveRecord::Base
        declare_schema do
          string :name, limit: 127, index: true

          timestamps
        end
      end

      class IndexDefinitionCompoundIndexModel < ActiveRecord::Base
        declare_schema do
          integer :fk1_id
          integer :fk2_id

          timestamps
        end
      end
    end

    describe 'instance methods' do
      let(:model) { model_class.new }
      let(:fields) { ['last_name', 'first_name'] }
      let(:options) { {} }
      subject(:instance) { described_class.new(model_class, fields, **options) }

      describe 'attr_readers' do
        describe '#table' do
          subject { instance.table }

          it { is_expected.to eq(model_class.table_name) }

          context 'with table_name option' do
            let(:options) { { table_name: 'auth_users' } }

            it { is_expected.to eq('auth_users') }
          end
        end

        describe '#fields' do
          subject { instance.fields }

          it { is_expected.to eq(fields) }
        end

        describe '#explicit_name' do
          subject { instance.explicit_name }

          it { is_expected.to eq(nil) }

          context 'with name option' do
            let(:options) { { name: 'index_auth_users_on_last_name_and_first_name' } }

            it { is_expected.to eq('index_auth_users_on_last_name_and_first_name') }
          end
        end

        describe '#length' do
          subject { instance.length }
          let(:options) { { length: length } }

          context 'with integer length' do
            let(:length) { 2 }

            it { is_expected.to eq(length) }
          end

          context 'with Hash length' do
            let(:length) { { name: 2 } }

            it { is_expected.to eq(length) }
          end
        end

        describe '#options' do
          subject { instance.options }
          let(:options) { { name: 'my_index', unique: false, where: "(name like 'a%')", length: 10 } }

          it { is_expected.to eq(options) }
        end

        describe '#with_name' do
          subject { instance.with_name('new_name') }

          it { is_expected.to be_kind_of(described_class) }
          it { expect(instance.name).to eq('index_index_definition_test_models_on_last_name_and_first_name') }
          it { expect(subject.name).to eq('new_name') }
        end
      end
    end

    describe 'class methods' do
      let(:model) { model_class.new }

      describe 'index_definitions' do
        it do
          expect(model_class.index_definitions.size).to eq(1)

          sample = model_class.index_definitions.to_a.first
          expect(sample.name).to eq('index_index_definition_test_models_on_name')
          expect(sample.fields).to eq(['name'])
          expect(sample.unique).to eq(false)
        end
      end

      describe 'has index_definitions_with_primary_key' do
        it do
          expect(model_class.index_definitions_with_primary_key).to be_kind_of(Set)
          result = model_class.index_definitions_with_primary_key.sort_by(&:name)
          expect(result.size).to eq(2)

          expect(result[0].name).to eq('PRIMARY')
          expect(result[0].fields).to eq(['id'])
          expect(result[0].unique).to eq(true)

          expect(result[1].name).to eq('index_index_definition_test_models_on_name')
          expect(result[1].fields).to eq(['name'])
          expect(result[1].unique).to eq(false)
        end
      end
    end

    context 'with a migrated database' do
      before do
        ActiveRecord::Base.connection.execute <<~EOS
          CREATE TABLE index_definition_test_models (
            id INTEGER NOT NULL PRIMARY KEY,
            name #{if defined?(SQLite3) then 'TEXT' else 'VARCHAR(255)' end} NOT NULL
          )
        EOS
        ActiveRecord::Base.connection.execute <<~EOS
          CREATE UNIQUE INDEX index_definition_test_models_on_name ON index_definition_test_models(name)
        EOS
        ActiveRecord::Base.connection.execute <<~EOS
          CREATE TABLE index_definition_compound_index_models (
            fk1_id INTEGER NOT NULL,
            fk2_id INTEGER NOT NULL,
            PRIMARY KEY (fk1_id, fk2_id)
          )
        EOS
        ActiveRecord::Base.connection.schema_cache.clear!
      end

      describe 'for_model' do
        subject { described_class.for_model(model_class) }

        context 'with single-column PK' do
          it 'returns the indexes for the model' do
            expect(subject.size).to eq(2), subject.inspect
            expect(subject[0].name).to eq('index_definition_test_models_on_name')
            expect(subject[0].columns).to eq(['name'])
            expect(subject[0].unique).to eq(true)
            expect(subject[1].name).to eq('PRIMARY')
            expect(subject[1].columns).to eq(['id'])
            expect(subject[1].unique).to eq(true)
          end
        end

        context 'with compound-column PK' do
          let(:model_class) { IndexDefinitionCompoundIndexModel }

          it 'returns the indexes for the model' do
            expect(subject.size).to eq(1), subject.inspect
            expect(subject[0].name).to eq('PRIMARY')
            expect(subject[0].columns).to eq(['fk1_id', 'fk2_id'])
            expect(subject[0].unique).to eq(true)
          end
        end
      end
    end
  end

  context 'with no side effects' do
    describe '.default_index_name' do
      let(:table_name2) { 'users' }
      let(:columns2) { ['last_name', 'first_name', 'middle_name', ] }
      subject { described_class.default_index_name(table_name2, columns2) }
      around do |spec|
        orig_value = DeclareSchema.max_index_and_constraint_name_length
        DeclareSchema.max_index_and_constraint_name_length = max_index_and_constraint_name_length
        spec.run
      ensure
        DeclareSchema.max_index_and_constraint_name_length = orig_value
      end

      context 'with unlimited max_index_and_constraint_name_length' do
        let(:max_index_and_constraint_name_length) { nil }

        it { is_expected.to eq("index_users_on_last_name_and_first_name_and_middle_name") }
      end

      context 'with short max_index_and_constraint_name_length' do
        let(:max_index_and_constraint_name_length) { 40 }

        it { is_expected.to eq("users__last_name_first_name_middle_name") }
      end

      context 'with long table name' do
        let(:table_name2) { 'user_domains_extra' }
        {
          34 => '__last_name_first_name_middle_name',
          35 => 'u__last_name_first_name_middle_name',
          36 => 'u4__last_name_first_name_middle_name',
          37 => 'us4__last_name_first_name_middle_name',
          38 => 'us48__last_name_first_name_middle_name',
          39 => 'use48__last_name_first_name_middle_name',
          40 => 'use481__last_name_first_name_middle_name',
          41 => 'user481__last_name_first_name_middle_name',
          42 => 'user4814__last_name_first_name_middle_name',
          43 => 'user_4814__last_name_first_name_middle_name',
          44 => 'user_d4814__last_name_first_name_middle_name',
          45 => 'user_do4814__last_name_first_name_middle_name',
          46 => 'user_dom4814__last_name_first_name_middle_name',
          47 => 'user_doma4814__last_name_first_name_middle_name',
          48 => 'user_domai4814__last_name_first_name_middle_name',
          49 => 'user_domain4814__last_name_first_name_middle_name',
          50 => 'user_domains4814__last_name_first_name_middle_name',
          51 => 'user_domains_4814__last_name_first_name_middle_name',
          52 => 'user_domains_extra__last_name_first_name_middle_name',
          53 => 'user_domains_extra__last_name_first_name_middle_name',
        }.each do |len, index_name|
          context "with max_index_and_constraint_name_length of #{len}" do
            let(:max_index_and_constraint_name_length) { len }

            it { is_expected.to eq(index_name) }
          end
        end

        context "with max_index_and_constraint_name_length shorter than columns suffix" do
          let(:max_index_and_constraint_name_length) { 33 }

          it 'raises' do
            expect { subject }.to raise_exception(DeclareSchema::Model::IndexDefinition::IndexNameTooLongError,
                                                  /Default index name '__last_name_first_name_middle_name' exceeds configured limit of 33 characters\. Use the `name:` option to give it a shorter name, or adjust DeclareSchema\.max_index_and_constraint_name_length/i)
          end
        end
      end
    end
  end
  # TODO: fill out remaining tests
end