require 'forwardable'
require 'virtus'
require 'json'
require 'cartodb-common'
require_relative '../markdown_render'
require_relative './presenter'
require_relative './name_checker'
require_relative '../permission'
require_relative './relator'
require_relative './like'
require_relative '../table/privacy_manager'
require_relative '../../../services/minimal-validation/validator'
require_relative '../../helpers/embed_redis_cache'
require_dependency 'cartodb/redis_vizjson_cache'
require_dependency 'carto/visualization'

# Every table has always at least one visualization (the "canonical visualization"), of type 'table',
# which shares the same privacy options as the table and gets synced.
# Users can create new visualizations, which will never be of type 'table',
# and those will use named maps when any source tables are private
module CartoDB
  module Visualization
    class Member
      extend Forwardable
      include Virtus.model
      include CacheHelper
      include Carto::VisualizationDependencies

      PRIVACY_PUBLIC       = 'public'.freeze        # published and listable in public user profile
      PRIVACY_PRIVATE      = 'private'.freeze       # not published (viz.json and embed_map should return 404)
      PRIVACY_LINK         = 'link'.freeze          # published but not listen in public profile
      PRIVACY_PROTECTED    = 'password'.freeze      # published but password protected

      TYPE_CANONICAL  = 'table'.freeze
      TYPE_DERIVED    = 'derived'.freeze
      TYPE_SLIDE      = 'slide'.freeze
      TYPE_REMOTE = 'remote'.freeze
      TYPE_KUVIZ = 'kuviz'.freeze

      VALID_TYPES = [TYPE_CANONICAL, TYPE_DERIVED, TYPE_SLIDE, TYPE_REMOTE].freeze

      KIND_GEOM   = 'geom'.freeze
      KIND_RASTER = 'raster'.freeze

      PRIVACY_VALUES = [PRIVACY_PUBLIC, PRIVACY_PRIVATE, PRIVACY_LINK, PRIVACY_PROTECTED].freeze
      TEMPLATE_NAME_PREFIX = 'tpl_'.freeze

      PERMISSION_READONLY = CartoDB::Permission::ACCESS_READONLY
      PERMISSION_READWRITE = CartoDB::Permission::ACCESS_READWRITE

      TOKEN_DIGEST = '6da98b2da1b38c5ada2547ad2c3268caa1eb58dc20c9144ead844a2eda1917067a06dcb54833ba2'.freeze

      VERSION_BUILDER = 3

      DEFAULT_OPTIONS_VALUE = '{}'.freeze

      # Upon adding new attributes modify also:
      # services/data-repository/spec/unit/backend/sequel_spec.rb -> before do
      # spec/support/helpers.rb -> random_attributes_for_vis_member
      # app/models/visualization/presenter.rb
      attribute :id,                  String
      attribute :name,                String
      attribute :display_name,        String
      attribute :map_id,              String
      attribute :active_layer_id,     String
      attribute :type,                String
      attribute :privacy,             String
      attribute :tags,                Array[String], default: []
      attribute :description,         String
      attribute :license,             String
      attribute :source,              String
      attribute :attributions,        String
      attribute :title,               String
      attribute :created_at,          Time
      attribute :updated_at,          Time
      attribute :encrypted_password,  String, default: nil
      attribute :password_salt,       String, default: nil
      attribute :user_id,             String
      attribute :permission_id,       String
      attribute :locked,              Boolean, default: false
      attribute :parent_id,           String, default: nil
      attribute :kind,                String, default: KIND_GEOM
      attribute :prev_id,             String, default: nil
      attribute :next_id,             String, default: nil
      attribute :bbox,                String, default: nil
      attribute :auth_token,          String, default: nil
      attribute :version,             Integer
      # Don't use directly, use instead getter/setter "transition_options"
      attribute :slide_transition_options,  String, default: DEFAULT_OPTIONS_VALUE
      attribute :active_child,        String, default: nil

      def_delegators :validator,    :errors, :full_errors
      def_delegators :relator,      *Relator::INTERFACE

      # This get called not only when creating a new but also when populating from the Collection
      def initialize(attributes={}, repository=Visualization.repository, name_checker=nil)
        super(attributes)
        @repository     = repository
        self.id         ||= @repository.next_id
        @name_checker   = name_checker
        @validator      = MinimalValidator::Validator.new
        self.permission_change_valid = true   # Changes upon set of different permission_id
        # this flag is passed to the table in case of canonical visualizations. It's used to say to the table to not touch the database and only change the metadata information, useful for ghost tables
        self.register_table_only = false
        @redis_vizjson_cache = RedisVizjsonCache.new()
        @old_privacy = @privacy
      end

      def self.remote_member(name, user_id, privacy, description, tags, license, source, attributions, display_name)
        Member.new({
          name: name,
          user_id: user_id,
          privacy: privacy,
          description: description,
          tags: tags,
          license: license,
          source: source,
          attributions: attributions,
          display_name: display_name,
          type: TYPE_REMOTE})
      end

      def transition_options
        ::JSON.parse(self.slide_transition_options).symbolize_keys
      end

      def transition_options=(value)
        self.slide_transition_options = ::JSON.dump(value.nil? ? DEFAULT_OPTIONS_VALUE : value)
      end

      def ==(other_vis)
        self.id == other_vis.id
      end

      def default_privacy
        can_be_private? ? PRIVACY_LINK : PRIVACY_PUBLIC
      end

      def store
        raise CartoDB::InvalidMember.new(validator.errors) unless self.valid?
        do_store

        self
      end

      def store_from_map(fields)
        self.map_id = fields[:map_id]
        do_store(false)
        self
      end

      def store_using_table(table_privacy_changed = false)
        do_store(false, table_privacy_changed)
        self
      end

      def valid?
        validator.errors.store(:type, "Visualization type is not valid") unless valid_type?
        validator.errors.store(:user, "Viewer users can't store visualizations") if user.viewer

        validator.validate_presence_of(name: name, privacy: privacy, type: type, user_id: user_id)
        validator.validate_in(:privacy, privacy, PRIVACY_VALUES)
        # do not validate names for slides, it's never used
        validator.validate_uniqueness_of(:name, available_name?) unless type_slide?

        if privacy == PRIVACY_PROTECTED
          validator.validate_presence_of_with_custom_message(
            { encrypted_password: encrypted_password },
            "password can't be blank")
        end

        # Allow only "maintaining" privacy link for everyone but not setting it
        if privacy == PRIVACY_LINK && privacy_changed
          if derived?
            validator.validate_expected_value(:private_maps_enabled, true, user.private_maps_enabled)
          else
            validator.validate_expected_value(:private_tables_enabled, true, user.private_tables_enabled)
          end
        end

        if type_slide?
          if parent_id.nil?
            validator.errors.store(:parent_id, "Type #{TYPE_SLIDE} must have a parent") if parent_id.nil?
          else
            begin
              parent_member = Member.new(id:parent_id).fetch
              if parent_member.type != TYPE_DERIVED
                validator.errors.store(:parent_id, "Type #{TYPE_SLIDE} must have parent of type #{TYPE_DERIVED}")
              end
            rescue KeyError
              validator.errors.store(:parent_id, "Type #{TYPE_SLIDE} has non-existing parent id")
            end
          end
        else
          validator.errors.store(:parent_id, "Type #{type} must not have parent") unless parent_id.nil?
        end

        unless permission_id.nil?
          validator.errors.store(:permission_id, 'Cannot modify permission') unless permission_change_valid
        end

        if !license.nil? && !license.empty? && Carto::License.find(license.to_sym).nil?
          validator.errors.store(:license, 'License should be an empty or a valid value')
        end

        validator.valid?
      end

      def valid_type?
        VALID_TYPES.include?(type)
      end

      def fetch
        data = repository.fetch(id)
        raise KeyError if data.nil?
        self.attributes = data
        self.name_changed = false
        @old_privacy = @privacy
        self.privacy_changed = false
        self.permission_change_valid = true
        self.dirty = false
        validator.reset
        self
      end

      def delete_from_table
        delete(true)
      end

      def delete(from_table_deletion = false)
        raise CartoDB::InvalidMember.new(user: "Viewer users can't delete visualizations") if user.viewer

        repository.transaction do
          unlink_self_from_list!

          support_tables.delete_all

          overlays.map(&:destroy)
          safe_sequel_delete do
            # "Mark" that this vis id is the destructor to avoid cycles: Vis -> Map -> relatedvis (Vis again)
            related_map = map
            related_map.being_destroyed_by_vis_id = id
            related_map.destroy
          end if map
          safe_sequel_delete { table.destroy } if type == TYPE_CANONICAL && table && !from_table_deletion
          safe_sequel_delete do
            children.map do |child|
              # Refetch each item before removal so Relator reloads prev/next cursors
              child.fetch.delete
            end
          end

          # Avoid invalidating if the visualization has already been destroyed
          # This happens deleting a canonical visualization, which triggers a table deletion,
          # which triggers a second deletion of the same visualization
          carto_vis = carto_visualization
          if carto_vis
            Carto::NamedMaps::Api.new(carto_vis).destroy
            invalidate_cache
          end

          safe_sequel_delete { permission.destroy_shared_entities } if permission
          safe_sequel_delete { repository.delete(id) }
          safe_sequel_delete { permission.destroy } if permission
          attributes.keys.each { |key| send("#{key}=", nil) }
        end

        self
      end

      # A visualization is linked to a table when it uses that table in a layergroup (but is not the canonical table)
      def unlink_from(table)
        invalidate_cache
        remove_layers_from(table)
      end

      def name=(name)
        name = name.downcase if name && table?
        self.name_changed = true if name != @name && !@name.nil?
        self.old_name = @name
        super(name)
      end

      def description=(description)
        self.dirty = true if description != @description && !@description.nil?
        super(description)
      end

      def attributions=(value)
        self.dirty = true if value != @attributions
        self.attributions_changed = true if value != @attributions
        super(value)
      end

      def permission_id=(permission_id)
        self.permission_change_valid = false
        self.permission_change_valid = true if (@permission_id.nil? || @permission_id == permission_id)
        super(permission_id)
      end

      def privacy=(new_privacy)
        new_privacy = new_privacy.downcase if new_privacy
        if new_privacy != @privacy && !@privacy.nil?
          self.privacy_changed = true
          @old_privacy = @privacy
        end
        super(new_privacy)
      end

      def tags=(tags)
        tags.reject!(&:blank?) if tags
        super(tags)
      end

      def version=(version)
        self.dirty = true
        super(version)
      end

      def public?
        privacy == PRIVACY_PUBLIC
      end

      def public_with_link?
        privacy == PRIVACY_LINK
      end

      def private?
        privacy == PRIVACY_PRIVATE and not organization?
      end

      def is_privacy_private?
        privacy == PRIVACY_PRIVATE
      end

      def can_be_private?(owner = user)
        derived? ? owner.try(:private_maps_enabled) : owner.try(:private_tables_enabled)
      end

      def organization?
        privacy == PRIVACY_PRIVATE and permission.acl.size > 0
      end

      def password_protected?
        privacy == PRIVACY_PROTECTED
      end

      # Called by controllers upon rendering
      def to_json(options={})
        ::JSON.dump(to_hash(options))
      end

      def to_hash(options={})
        presenter = Presenter.new(self, options.merge(real_privacy: true))
        options.delete(:public_fields_only) === true ? presenter.to_public_poro : presenter.to_poro
      end

      def to_vizjson(options={})
        @redis_vizjson_cache.cached(id, options.fetch(:https_request, false)) do
          calculate_vizjson(options)
        end
      end

      def is_owner?(user)
        user && user.id == user_id
      end

      # @param user ::User
      # @param permission_type String PERMISSION_xxx
      def has_permission?(user, permission_type)
        return false if user.viewer && permission_type == PERMISSION_READWRITE
        return is_owner?(user) if permission_id.nil?
        is_owner?(user) || permission.permitted?(user, permission_type)
      end

      def can_copy?(user)
        !raster_kind? && has_permission?(user, PERMISSION_READONLY)
      end

      def raster_kind?
        kind == KIND_RASTER
      end

      def users_with_permissions(permission_types)
        permission.users_with_permissions(permission_types)
      end

      def varnish_key
        sorted_table_names = related_tables.map{ |table|
          "#{user.database_schema}.#{table.name}"
        }.sort { |i, j|
          i <=> j
        }.join(',')
        "#{user.database_name}:#{sorted_table_names},#{id}"
      end

      def surrogate_key
        get_surrogate_key(CartoDB::SURROGATE_NAMESPACE_VISUALIZATION, self.id)
      end

      def varnish_vizjson_key
        ".*#{id}:vizjson"
      end

      def derived?
        type == TYPE_DERIVED
      end

      def table?
        type == TYPE_CANONICAL
      end
      # Used at Carto::Api::VisualizationPresenter
      alias :canonical? :table?

      def type_slide?
        type == TYPE_SLIDE
      end

      def kuviz?
        type == TYPE_KUVIZ
      end

      def invalidate_cache
        invalidate_redis_cache
        invalidate_varnish_vizjson_cache

        parent.invalidate_cache unless parent_id.nil?
      end

      def has_private_tables?
        has_private_tables = false
        related_tables.each { |table|
          has_private_tables |= table.private?
        }
        has_private_tables
      end

      # Despite storing always a named map, no need to retrieve it for "public" visualizations
      def retrieve_named_map?
        password_protected? || has_private_tables?
      end

      def password=(value)
        if value && value.size > 0
          @password_salt = ""
          @encrypted_password = Carto::Common::EncryptionService.encrypt(password: value,
                                                                         secret: Cartodb.config[:password_secret])
          self.dirty = true
        end
      end

      def has_password?
        ( !@password_salt.nil? && !@encrypted_password.nil? )
      end

      def password_valid?(password)
        Carto::Common::EncryptionService.verify(password: password, secure_password: @encrypted_password,
                                                salt: @password_salt, secret: Cartodb.config[:password_secret])
      end

      def remove_password
        @password_salt = nil
        @encrypted_password = nil
      end

      # To be stored with the named map
      def make_auth_token
        Carto::Common::EncryptionService.make_token(length: 64)
      end

      def get_auth_token
        if auth_token.nil?
          auth_token = make_auth_token
          store
        end
        auth_token
      end

      def get_auth_tokens
        [get_auth_token]
      end

      def supports_private_maps?
        !user.nil? && user.private_maps_enabled?
      end

      def published?
        !is_privacy_private? && (!builder? || !derived? || mapcapped?)
      end

      def builder?
        version == VERSION_BUILDER
      end

      # @param other_vis CartoDB::Visualization::Member|nil
      # Note: Changes state both of self, other_vis and other affected list items, but only reloads self & other_vis
      def set_next_list_item!(other_vis)
        repository.transaction do
          close_list_gap(other_vis)

          # Now insert other_vis after self
          unless other_vis.nil?
            if self.next_id.nil?
              other_vis.next_id = nil
            else
              other_vis.next_id = self.next_id
              next_item = next_list_item
              next_item.prev_id = other_vis.id
              next_item.store
            end
            self.next_id = other_vis.id
            other_vis.prev_id = self.id
            other_vis.store
                     .fetch
          end

          store
        end

        fetch
      end

      # @param other_vis CartoDB::Visualization::Member|nil
      # Note: Changes state both of self, other_vis and other affected list items, but only reloads self & other_vis
      def set_prev_list_item!(other_vis)
        repository.transaction do
          close_list_gap(other_vis)

          # Now insert other_vis after self
          unless other_vis.nil?
            if self.prev_id.nil?
              other_vis.prev_id = nil
            else
              other_vis.prev_id = self.prev_id
              prev_item = prev_list_item
              prev_item.next_id = other_vis.id
              prev_item.store
            end
            self.prev_id = other_vis.id
            other_vis.next_id = self.id
            other_vis.store
                     .fetch
          end

          store
        end
        fetch
      end

      def unlink_self_from_list!
        repository.transaction do
          unless self.prev_id.nil?
            prev_item = prev_list_item
            prev_item.next_id = self.next_id
            prev_item.store
          end
          unless self.next_id.nil?
            next_item = next_list_item
            next_item.prev_id = self.prev_id
            next_item.store
          end
          self.prev_id = nil
          self.next_id = nil
        end
      end

      def liked_by?(user)
        !likes.select { |like| like.actor == user.id }.first.nil?
      end

      # @param viewer_user ::User
      def qualified_name(viewer_user=nil)
        if viewer_user.nil? || is_owner?(viewer_user)
          name
        else
          "#{user.sql_safe_database_schema}.#{name}"
        end
      end

      attr_accessor :register_table_only

      def invalidate_redis_cache
        @redis_vizjson_cache.invalidate(id)
        embed_redis_cache.invalidate(self.id)
      end

      def save_named_map
        return if type == TYPE_REMOTE
        return true if named_map_updates_disabled?

        unless @updating_named_maps
          SequelRails.connection.after_commit do
            @updating_named_maps = false
            (get_named_map ? update_named_map : create_named_map) if carto_visualization
          end
          @updating_named_maps = true
        end
        true
      end

      def get_named_map
        return false if type == TYPE_REMOTE

        Carto::NamedMaps::Api.new(carto_visualization).show if carto_visualization
      end

      def license_info
        if !license.nil?
          Carto::License.find(license.to_sym)
        end
      end

      def attributions_from_derived_visualizations
        related_canonical_visualizations.map(&:attributions).reject {|attribution| attribution.blank?}
      end

      def map
        @map ||= ::Map.where(id: map_id).first
      end

      def mapcaps
        Carto::Mapcap.latest_for_visualization(id)
      end

      def latest_mapcap
        mapcaps.first
      end

      def mapcapped?
        mapcaps.exists?
      end

      def invalidate_for_permissions_change
        # A change in permissions should trigger the same invalidations as a privacy change
        self.privacy_changed = true
        invalidate_cache
        save_named_map
      end

      private

      attr_reader   :repository, :name_checker, :validator
      attr_accessor :privacy_changed, :name_changed, :old_name, :permission_change_valid, :dirty, :attributions_changed

      def named_map_updates_disabled?
        mapcapped? && !privacy_changed
      end

      def embed_redis_cache
        @embed_redis_cache ||= EmbedRedisCache.new($tables_metadata)
      end

      def calculate_vizjson(options={})
        vizjson_options = {
          full: false,
          user_name: user.username,
          user_api_key: user.api_key,
          user: user,
          viewer_user: user
        }.merge(options)
        VizJSON.new(self, vizjson_options, configuration).to_poro
      end

      def invalidate_varnish_vizjson_cache
        CartoDB::Varnish.new.purge(varnish_vizjson_key)
      end

      def close_list_gap(other_vis)
        reload_self = false

        if other_vis.nil?
          self.next_id = nil
          old_prev = nil
          old_next = nil
        else
          old_prev = other_vis.prev_list_item
          old_next = other_vis.next_list_item
        end

        # First close gap left by other_vis
        unless old_prev.nil?
          old_prev.next_id = old_next.nil? ? nil : old_next.id
          old_prev.store
          reload_self |= old_prev.id == self.id
        end
        unless old_next.nil?
          old_next.prev_id = old_prev.nil? ? nil : old_prev.id
          old_next.store
          reload_self |= old_next.id == self.id
        end

        fetch if reload_self
      end

      def do_store(propagate_changes = true, table_privacy_changed = false)
        self.version = user.new_visualizations_version if version.nil?

        if password_protected?
          raise CartoDB::InvalidMember.new('No password set and required') unless has_password?
        else
          remove_password
        end

        # Warning: imports create by default private canonical visualizations
        if type != TYPE_CANONICAL && @privacy == PRIVACY_PRIVATE && privacy_changed && !supports_private_maps?
          raise CartoDB::InvalidMember
        end

        perform_invalidations(table_privacy_changed)

        set_timestamps

        # Ensure a permission is set before saving the visualization
        if permission.nil?
          perm = CartoDB::Permission.new
          perm.owner = user
          perm.save
          @permission_id = perm.id
        end
        repository.store(id, attributes.to_hash)

        restore_previous_privacy unless save_named_map

        propagate_attribution_change if table
        if type == TYPE_REMOTE || type == TYPE_CANONICAL
          propagate_privacy_and_name_to(table) if table and propagate_changes
        else
          propagate_name_to(table) if table and propagate_changes
        end
      end

      def restore_previous_privacy
        unless @old_privacy.nil?
          self.privacy = @old_privacy
          attributes[:privacy] = @old_privacy
          repository.store(id, attributes.to_hash)
        end
      rescue => exception
        CartoDB.notify_exception(exception, user: user, message: "Error restoring previous visualization privacy")
        raise exception
      end

      def perform_invalidations(table_privacy_changed)
        # previously we used 'invalidate_cache' but due to public_map displaying all the user public visualizations,
        # now we need to purgue everything to avoid cached stale data or public->priv still showing scenarios
        if name_changed || privacy_changed || table_privacy_changed || dirty
          invalidate_cache
        end

        # When a table's relevant data is changed, propagate to all who use it or relate to it
        if dirty && table
          table.affected_visualizations.each do |affected_vis|
            affected_vis.invalidate_cache
          end
        end
      end

      def create_named_map
        return unless map
        Carto::NamedMaps::Api.new(carto_visualization).create
      end

      def update_named_map
        return if named_map_updates_disabled? || map.nil?

        # A visualization destroy triggers destroys on all its layers. Each
        # layer destroy, will trigger an update back to the visualization. When
        # the last layer is destroyed, and the visualization named map template
        # is generated to be updated, it will contain no layers, causing an
        # error at the Maps API. This is a hack to prevent that update and error
        # from happening. A better way to solve this would be to get
        # callbacks under control.
        presentation_visualization = carto_visualization.try(:for_presentation)
        if presentation_visualization && presentation_visualization.layers.any?
          Carto::NamedMaps::Api.new(presentation_visualization).update
        end
      end

      def propagate_privacy_and_name_to(table)
        raise "Empty table sent to Visualization::Member propagate_privacy_and_name_to()" unless table
        propagate_privacy_to(table) if privacy_changed
        propagate_name_to(table)    if name_changed
      end

      def propagate_privacy_to(table)
        if type == TYPE_CANONICAL
          CartoDB::TablePrivacyManager.new(table)
                                      .set_from_visualization(self)
                                      .update_cdb_tablemetadata
        end
        self
      end

      # @param table Table
      def propagate_name_to(table)
        table.register_table_only = register_table_only
        table.name = name
        table.update(name: name)
        if name_changed
          support_tables.rename(old_name, name, recreate_constraints=true, seek_parent_name=old_name)
        end
        self
      rescue => exception
        if name_changed && !(exception.to_s =~ /relation.*does not exist/)
          revert_name_change(old_name)
        end
        raise CartoDB::InvalidMember.new(exception.to_s)
      end

      def propagate_attribution_change
        return unless attributions_changed

        table.propagate_attribution_change(attributions)
      end

      def revert_name_change(previous_name)
        self.name = previous_name
        store
      rescue => exception
        raise CartoDB::InvalidMember.new(exception.to_s)
      end

      def set_timestamps
        self.created_at ||= Time.now
        self.updated_at = Time.now
        self
      end

      def relator
        Relator.new(map, attributes)
      end

      def name_checker
        @name_checker || NameChecker.new(user)
      end

      def available_name?
        return true unless user && name_changed
        name_checker.available?(name)
      end

      def remove_layers_from(table)
        related_layers_from(table).each do |layer|
          # Using delete to avoid hooks, as they generate a conflict between ORMs and are
          # not needed in this case since they are already triggered by deleting the layer
          Carto::Analysis.find_by_natural_id(id, layer.source_id).try(:delete) if layer.source_id

          map.remove_layer(layer)
          layer.destroy
        end
        self.active_layer_id = layers(:cartodb).first.nil? ? nil : layers(:cartodb).first.id
        store
      end

      def related_layers_from(table)
        layers(:cartodb).select do |layer|
          (layer.user_tables.map(&:name) + [layer.options.fetch('table_name', nil)]).include?(table.name)
        end
      end

      def configuration
        return {} unless defined?(Cartodb)
        Cartodb.config
      end

      def safe_sequel_delete
        yield
      rescue Sequel::NoExistingObject => exception
        # INFO: don't fail on nonexistant object delete
        CartoDB.notify_exception(exception)
      end

      def carto_visualization
        Carto::Visualization.where(id: id).first
      end
    end
  end
end