ash_postgres/lib/data_layer.ex

defmodule AshPostgres.DataLayer do
  @moduledoc """
  A postgres data layer that levereges Ecto's postgres capabilities.
  """

  @manage_tenant %Ash.Dsl.Section{
    name: :manage_tenant,
    describe: """
    Configuration for the behavior of a resource that manages a tenant
    """,
    schema: [
      template: [
        type: {:custom, __MODULE__, :tenant_template, []},
        required: true,
        doc: """
        A template that will cause the resource to create/manage the specified schema.

        Use this if you have a resource that, when created, it should create a new tenant
        for you. For example, if you have a `customer` resource, and you want to create
        a schema for each customer based on their id, e.g `customer_10` set this option
        to `["customer_", :id]`. Then, when this is created, it will create a schema called
        `["customer_", :id]`, and run your tenant migrations on it. Then, if you were to change
        that customer's id to `20`, it would rename the schema to `customer_20`. Generally speaking
        you should avoid changing the tenant id.
        """
      ],
      create?: [
        type: :boolean,
        default: true,
        doc: "Whether or not to automatically create a tenant when a record is created"
      ],
      update?: [
        type: :boolean,
        default: true,
        doc: "Whether or not to automatically update the tenant name if the record is udpated"
      ]
    ]
  }

  @postgres %Ash.Dsl.Section{
    name: :postgres,
    describe: """
    Postgres data layer configuration
    """,
    sections: [
      @manage_tenant
    ],
    modules: [
      :repo
    ],
    schema: [
      repo: [
        type: :atom,
        required: true,
        doc:
          "The repo that will be used to fetch your data. See the `AshPostgres.Repo` documentation for more"
      ],
      migrate?: [
        type: :boolean,
        default: true,
        doc:
          "Whether or not to include this resource in the generated migrations with `mix ash.generate_migrations`"
      ],
      base_filter_sql: [
        type: :string,
        doc:
          "A raw sql version of the base_filter, e.g `representative = true`. Required if trying to create a unique constraint on a resource with a base_filter"
      ],
      skip_unique_indexes: [
        type: {:custom, __MODULE__, :validate_skip_unique_indexes, []},
        default: false,
        doc: "Skip generating unique indexes when generating migrations"
      ],
      table: [
        type: :string,
        required: true,
        doc: "The table to store and read the resource from"
      ]
    ]
  }

  alias Ash.Filter
  alias Ash.Query.{Expression, Not, Ref}

  alias Ash.Query.Operator.{
    Eq,
    GreaterThan,
    GreaterThanOrEqual,
    In,
    IsNil,
    LessThan,
    LessThanOrEqual
  }

  alias AshPostgres.Functions.TrigramSimilarity

  import AshPostgres, only: [table: 1, repo: 1]

  @behaviour Ash.DataLayer

  use Ash.Dsl.Extension,
    sections: [@postgres],
    transformers: [AshPostgres.Transformers.VerifyRepo]

  @doc false
  def tenant_template(value) do
    value = List.wrap(value)

    if Enum.all?(value, &(is_binary(&1) || is_atom(&1))) do
      {:ok, value}
    else
      {:error, "Expected all values for `manages_tenant` to be strings or atoms"}
    end
  end

  @doc false
  def validate_skip_unique_indexes(indexes) do
    indexes = List.wrap(indexes)

    if Enum.all?(indexes, &is_atom/1) do
      {:ok, indexes}
    else
      {:error, "All indexes to skip must be atoms"}
    end
  end

  import Ecto.Query, only: [from: 2, subquery: 1]

  @impl true
  def can?(_, :async_engine), do: true
  def can?(_, :transact), do: true
  def can?(_, :composite_primary_key), do: true
  def can?(_, :upsert), do: true

  def can?(resource, {:join, other_resource}) do
    data_layer = Ash.Resource.data_layer(resource)
    other_data_layer = Ash.Resource.data_layer(other_resource)
    data_layer == other_data_layer and repo(data_layer) == repo(other_data_layer)
  end

  def can?(resource, {:lateral_join, other_resource}) do
    data_layer = Ash.Resource.data_layer(resource)
    other_data_layer = Ash.Resource.data_layer(other_resource)
    data_layer == other_data_layer and repo(data_layer) == repo(other_data_layer)
  end

  def can?(_, :boolean_filter), do: true
  def can?(_, {:aggregate, :count}), do: true
  def can?(_, :aggregate_filter), do: true
  def can?(_, :aggregate_sort), do: true
  def can?(_, :create), do: true
  def can?(_, :read), do: true
  def can?(_, :update), do: true
  def can?(_, :destroy), do: true
  def can?(_, :filter), do: true
  def can?(_, :limit), do: true
  def can?(_, :offset), do: true
  def can?(_, :multitenancy), do: true
  def can?(_, {:filter_operator, %{right: %Ref{}}}), do: false
  def can?(_, {:filter_operator, %Eq{left: %Ref{}}}), do: true
  def can?(_, {:filter_operator, %In{left: %Ref{}}}), do: true
  def can?(_, {:filter_operator, %LessThan{left: %Ref{}}}), do: true
  def can?(_, {:filter_operator, %GreaterThan{left: %Ref{}}}), do: true
  def can?(_, {:filter_operator, %LessThanOrEqual{left: %Ref{}}}), do: true
  def can?(_, {:filter_operator, %GreaterThanOrEqual{left: %Ref{}}}), do: true
  def can?(_, {:filter_operator, %IsNil{left: %Ref{}}}), do: true
  def can?(_, {:filter_function, %TrigramSimilarity{}}), do: true
  def can?(_, {:query_aggregate, :count}), do: true
  def can?(_, :sort), do: true
  def can?(_, {:sort, _}), do: true
  def can?(_, _), do: false

  @impl true
  def in_transaction?(resource) do
    repo(resource).in_transaction?()
  end

  @impl true
  def limit(query, nil, _), do: {:ok, query}

  def limit(query, limit, _resource) do
    {:ok, from(row in query, limit: ^limit)}
  end

  @impl true
  def source(resource) do
    table(resource)
  end

  @impl true
  def offset(query, nil, _), do: query

  def offset(%{offset: old_offset} = query, 0, _resource) when old_offset in [0, nil] do
    {:ok, query}
  end

  def offset(query, offset, _resource) do
    {:ok, from(row in query, offset: ^offset)}
  end

  @impl true
  def run_query(query, resource) do
    {:ok, repo(resource).all(query, repo_opts(query))}
  end

  defp repo_opts(%Ash.Changeset{tenant: tenant, resource: resource}) do
    repo_opts(%{tenant: tenant, resource: resource})
  end

  defp repo_opts(%{tenant: tenant, resource: resource}) when not is_nil(tenant) do
    if Ash.Resource.multitenancy_strategy(resource) == :context do
      [prefix: tenant]
    else
      []
    end
  end

  defp repo_opts(_), do: []

  @impl true
  def functions(resource) do
    config = repo(resource).config()

    if "pg_trgm" in (config[:installed_extensions] || []) do
      [
        AshPostgres.Functions.TrigramSimilarity
      ]
    else
      []
    end
  end

  @impl true
  def run_aggregate_query(query, aggregates, resource) do
    subquery = from(row in subquery(query), select: %{})

    query =
      Enum.reduce(
        aggregates,
        subquery,
        &add_subquery_aggregate_select(&2, &1, resource)
      )

    {:ok, repo(resource).one(query, repo_opts(query))}
  end

  @impl true
  def set_tenant(_resource, query, tenant) do
    {:ok, Ecto.Query.put_query_prefix(query, to_string(tenant))}
  end

  @impl true
  def run_aggregate_query_with_lateral_join(
        query,
        aggregates,
        root_data,
        source_resource,
        destination_resource,
        source_field,
        destination_field
      ) do
    lateral_join_query =
      lateral_join_query(
        query,
        root_data,
        source_resource,
        source_field,
        destination_field
      )

    subquery = from(row in subquery(lateral_join_query), select: %{})

    query =
      Enum.reduce(
        aggregates,
        subquery,
        &add_subquery_aggregate_select(&2, &1, destination_resource)
      )

    {:ok, repo(source_resource).one(query, repo_opts(:query))}
  end

  @impl true
  def run_query_with_lateral_join(
        query,
        root_data,
        source_resource,
        _destination_resource,
        source_field,
        destination_field
      ) do
    query =
      lateral_join_query(
        query,
        root_data,
        source_resource,
        source_field,
        destination_field
      )

    {:ok, repo(source_resource).all(query, repo_opts(query))}
  end

  defp lateral_join_query(
         query,
         root_data,
         source_resource,
         source_field,
         destination_field
       ) do
    source_values = Enum.map(root_data, &Map.get(&1, source_field))

    subquery =
      subquery(
        from(destination in query,
          where:
            field(destination, ^destination_field) ==
              field(parent_as(:source_record), ^source_field)
        )
      )

    source_resource
    |> Ash.Query.new()
    |> Ash.Query.data_layer_query()
    |> case do
      {:ok, data_layer_query} ->
        from(source in data_layer_query,
          as: :source_record,
          where: field(source, ^source_field) in ^source_values,
          inner_lateral_join: destination in ^subquery,
          on: field(source, ^source_field) == field(destination, ^destination_field),
          select: destination
        )

      {:error, error} ->
        {:error, error}
    end
  end

  @impl true
  def resource_to_query(resource),
    do: Ecto.Queryable.to_query({table(resource), resource})

  @impl true
  def create(resource, changeset) do
    changeset.data
    |> Map.update!(:__meta__, &Map.put(&1, :source, table(resource)))
    |> ecto_changeset(changeset)
    |> repo(resource).insert(repo_opts(changeset))
    |> case do
      {:ok, result} ->
        case maybe_create_tenant(resource, result) do
          :ok ->
            {:ok, result}

          {:error, error} ->
            {:error, error}
        end

      {:error, error} ->
        {:error, error}
    end
  rescue
    e ->
      {:error, e}
  end

  defp maybe_create_tenant(resource, result) do
    if AshPostgres.manage_tenant_create?(resource) do
      tenant_name = tenant_name(resource, result)

      AshPostgres.MultiTenancy.create_tenant(tenant_name, repo(resource))
    else
      :ok
    end
  end

  defp maybe_update_tenant(resource, changeset, result) do
    if AshPostgres.manage_tenant_update?(resource) do
      changing_tenant_name? =
        resource
        |> AshPostgres.manage_tenant_template()
        |> Enum.filter(&is_atom/1)
        |> Enum.any?(&Ash.Changeset.changing_attribute?(changeset, &1))

      if changing_tenant_name? do
        old_tenant_name = tenant_name(resource, changeset.data)

        new_tenant_name = tenant_name(resource, result)
        AshPostgres.MultiTenancy.rename_tenant(repo(resource), old_tenant_name, new_tenant_name)
      end
    end

    :ok
  end

  defp tenant_name(resource, result) do
    resource
    |> AshPostgres.manage_tenant_template()
    |> Enum.map_join(fn item ->
      if is_binary(item) do
        item
      else
        result
        |> Map.get(item)
        |> to_string()
      end
    end)
  end

  defp ecto_changeset(record, changeset) do
    Ecto.Changeset.change(record, changeset.attributes)
  end

  @impl true
  def upsert(resource, changeset) do
    repo_opts =
      changeset
      |> repo_opts()
      |> Keyword.put(:on_conflict, {:replace, Map.keys(changeset.attributes)})
      |> Keyword.put(:conflict_target, Ash.Resource.primary_key(resource))

    if AshPostgres.manage_tenant_update?(resource) do
      {:error, "Cannot currently upsert a resource that owns a tenant"}
    else
      changeset.data
      |> Map.update!(:__meta__, &Map.put(&1, :source, table(resource)))
      |> ecto_changeset(changeset)
      |> repo(resource).insert(repo_opts)
    end
  rescue
    e ->
      {:error, e}
  end

  @impl true
  def update(resource, changeset) do
    changeset.data
    |> Map.update!(:__meta__, &Map.put(&1, :source, table(resource)))
    |> ecto_changeset(changeset)
    |> repo(resource).update(repo_opts(changeset))
    |> case do
      {:ok, result} ->
        maybe_update_tenant(resource, changeset, result)

        {:ok, result}

      {:error, error} ->
        {:error, error}
    end
  rescue
    e ->
      {:error, e}
  end

  @impl true
  def destroy(resource, %{data: record} = changeset) do
    case repo(resource).delete(record, repo_opts(changeset)) do
      {:ok, _record} ->
        :ok

      {:error, error} ->
        {:error, error}
    end
  rescue
    e ->
      {:error, e}
  end

  @impl true
  def sort(query, sort, resource) do
    query = default_bindings(query, resource)

    sort
    |> sanitize_sort()
    |> Enum.reduce({:ok, query}, fn {order, sort}, {:ok, query} ->
      binding =
        case Map.fetch(query.__ash_bindings__.aggregates, sort) do
          {:ok, binding} ->
            binding

          :error ->
            0
        end

      new_query =
        Map.update!(query, :order_bys, fn order_bys ->
          order_bys = order_bys || []

          sort_expr = %Ecto.Query.QueryExpr{
            expr: [
              {order, {{:., [], [{:&, [], [binding]}, sort]}, [], []}}
            ]
          }

          order_bys ++ [sort_expr]
        end)

      {:ok, new_query}
    end)
  end

  defp sanitize_sort(sort) do
    sort
    |> List.wrap()
    |> Enum.map(fn
      {sort, order} -> {order, sort}
      sort -> sort
    end)
  end

  @impl true
  def filter(query, %{expression: false}, _resource) do
    impossible_query = from(row in query, where: false)
    {:ok, Map.put(impossible_query, :__impossible__, true)}
  end

  def filter(query, filter, _resource) do
    relationship_paths =
      filter
      |> Filter.relationship_paths()
      |> Enum.map(fn path ->
        if can_inner_join?(path, filter) do
          {:inner, relationship_path_to_relationships(filter.resource, path)}
        else
          {:left, relationship_path_to_relationships(filter.resource, path)}
        end
      end)

    new_query =
      query
      |> join_all_relationships(relationship_paths)
      |> add_filter_expression(filter)

    {:ok, new_query}
  end

  defp default_bindings(query, resource) do
    Map.put_new(query, :__ash_bindings__, %{
      current: Enum.count(query.joins) + 1,
      aggregates: %{},
      bindings: %{0 => %{path: [], type: :root, source: resource}}
    })
  end

  defp can_inner_join?(path, expr, seen_an_or? \\ false)

  defp can_inner_join?(path, %{expression: expr}, seen_an_or?),
    do: can_inner_join?(path, expr, seen_an_or?)

  defp can_inner_join?(_path, expr, _seen_an_or?) when expr in [nil, true, false], do: true

  defp can_inner_join?(path, %Expression{op: :and, left: left, right: right}, seen_an_or?) do
    can_inner_join?(path, left, seen_an_or?) || can_inner_join?(path, right, seen_an_or?)
  end

  defp can_inner_join?(path, %Expression{op: :or, left: left, right: right}, _) do
    can_inner_join?(path, left, true) && can_inner_join?(path, right, true)
  end

  defp can_inner_join?(
         path,
         %Not{expression: %Expression{op: :or, left: left, right: right}},
         seen_an_or?
       ) do
    can_inner_join?(
      path,
      %Expression{
        op: :and,
        left: %Not{expression: left},
        right: %Not{expression: right}
      },
      seen_an_or?
    )
  end

  defp can_inner_join?(path, %Not{expression: expression}, seen_an_or?) do
    can_inner_join?(path, expression, seen_an_or?)
  end

  defp can_inner_join?(
         search_path,
         %{__operator__?: true, left: %Ref{relationship_path: relationship_path}},
         seen_an_or?
       )
       when search_path == relationship_path do
    not seen_an_or?
  end

  defp can_inner_join?(
         search_path,
         %{__function__?: true, arguments: arguments},
         seen_an_or?
       ) do
    if Enum.any?(arguments, &match?(%Ref{relationship_path: ^search_path}, &1)) do
      not seen_an_or?
    else
      true
    end
  end

  defp can_inner_join?(_, _, _), do: true

  @impl true
  def add_aggregate(query, aggregate, _resource) do
    resource = aggregate.resource
    query = default_bindings(query, resource)

    {query, binding} =
      case get_binding(resource, aggregate.relationship_path, query, :aggregate) do
        nil ->
          relationship = Ash.Resource.relationship(resource, aggregate.relationship_path)
          subquery = aggregate_subquery(relationship, aggregate)

          new_query =
            join_all_relationships(
              query,
              [
                {{:aggregate, aggregate.name, subquery},
                 relationship_path_to_relationships(resource, aggregate.relationship_path)}
              ]
            )

          {new_query, get_binding(resource, aggregate.relationship_path, new_query, :aggregate)}

        binding ->
          {query, binding}
      end

    query_with_aggregate_binding =
      put_in(
        query.__ash_bindings__.aggregates,
        Map.put(query.__ash_bindings__.aggregates, aggregate.name, binding)
      )

    new_query =
      query_with_aggregate_binding
      |> add_aggregate_to_subquery(resource, aggregate, binding)
      |> select_aggregate(resource, aggregate)

    {:ok, new_query}
  end

  defp select_aggregate(query, resource, aggregate) do
    binding = get_binding(resource, aggregate.relationship_path, query, :aggregate)

    query =
      if query.select do
        query
      else
        from(row in query,
          select: row,
          select_merge: %{aggregates: %{}}
        )
      end

    %{query | select: add_to_select(query.select, binding, aggregate)}
  end

  defp add_to_select(
         %{expr: {:merge, _, [first, {:%{}, _, [{:aggregates, {:%{}, [], fields}}]}]}} = select,
         binding,
         %{load: nil} = aggregate
       ) do
    field =
      {:type, [],
       [
         {{:., [], [{:&, [], [binding]}, aggregate.name]}, [], []},
         Ash.Type.ecto_type(aggregate.type)
       ]}

    field_with_default =
      if aggregate.default_value do
        {:coalesce, [],
         [
           field,
           aggregate.default_value
         ]}
      end

    new_fields = [
      {aggregate.name, field_with_default}
      | fields
    ]

    %{select | expr: {:merge, [], [first, {:%{}, [], [{:aggregates, {:%{}, [], new_fields}}]}]}}
  end

  defp add_to_select(
         %{expr: expr} = select,
         binding,
         %{load: load_as} = aggregate
       ) do
    field =
      {:type, [],
       [
         {{:., [], [{:&, [], [binding]}, aggregate.name]}, [], []},
         Ash.Type.ecto_type(aggregate.type)
       ]}

    field_with_default =
      if aggregate.default_value do
        {:coalesce, [],
         [
           field,
           aggregate.default_value
         ]}
      end

    %{select | expr: {:merge, [], [expr, {:%{}, [], [{load_as, field_with_default}]}]}}
  end

  defp add_aggregate_to_subquery(query, resource, aggregate, binding) do
    new_joins =
      List.update_at(query.joins, binding - 1, fn join ->
        aggregate_query =
          if aggregate.authorization_filter do
            {:ok, filter} =
              filter(
                join.source.from.source.query,
                aggregate.authorization_filter,
                Ash.Resource.related(resource, aggregate.relationship_path)
              )

            filter
          else
            join.source.from.source.query
          end

        new_aggregate_query = add_subquery_aggregate_select(aggregate_query, aggregate, resource)

        put_in(join.source.from.source.query, new_aggregate_query)
      end)

    %{
      query
      | joins: new_joins
    }
  end

  defp aggregate_subquery(relationship, aggregate) do
    query =
      from(row in relationship.destination,
        group_by: ^relationship.destination_field,
        select: field(row, ^relationship.destination_field)
      )

    if aggregate.query && aggregate.query.tenant do
      Ecto.Query.put_query_prefix(query, aggregate.query.tenant)
    else
      query
    end
  end

  defp add_subquery_aggregate_select(query, %{kind: :count} = aggregate, resource) do
    query = default_bindings(query, aggregate.resource)
    key_to_count = List.first(Ash.Resource.primary_key(resource))
    type = Ash.Type.ecto_type(aggregate.type)

    field = {:count, [], [{{:., [], [{:&, [], [0]}, key_to_count]}, [], []}]}

    {params, filtered} =
      if aggregate.query do
        {params, expr} =
          filter_to_expr(
            aggregate.query.filter,
            query.__ash_bindings__.bindings,
            query.select.params
          )

        {params, {:filter, [], [field, expr]}}
      else
        {[], field}
      end

    cast = {:type, [], [filtered, type]}

    new_expr = {:merge, [], [query.select.expr, {:%{}, [], [{aggregate.name, cast}]}]}

    %{query | select: %{query.select | expr: new_expr, params: params}}
  end

  defp relationship_path_to_relationships(resource, path, acc \\ [])
  defp relationship_path_to_relationships(_resource, [], acc), do: Enum.reverse(acc)

  defp relationship_path_to_relationships(resource, [relationship | rest], acc) do
    relationship = Ash.Resource.relationship(resource, relationship)

    relationship_path_to_relationships(relationship.destination, rest, [relationship | acc])
  end

  defp join_all_relationships(query, relationship_paths, path \\ [], source \\ nil) do
    query = default_bindings(query, source)

    Enum.reduce(relationship_paths, query, fn
      {_join_type, []}, query ->
        query

      {join_type, [relationship | rest_rels]}, query ->
        source = source || relationship.source

        current_path = path ++ [relationship]

        current_join_type =
          case join_type do
            {:aggregate, _name, _agg} when rest_rels != [] ->
              :left

            other ->
              other
          end

        if has_binding?(source, Enum.reverse(current_path), query, current_join_type) do
          query
        else
          joined_query =
            join_relationship(
              query,
              relationship,
              Enum.map(path, & &1.name),
              current_join_type,
              source
            )

          joined_query_with_distinct = add_distinct(relationship, join_type, joined_query)

          join_all_relationships(
            joined_query_with_distinct,
            [{join_type, rest_rels}],
            current_path,
            source
          )
        end
    end)
  end

  defp has_binding?(resource, path, query, {:aggregate, _, _}),
    do: has_binding?(resource, path, query, :aggregate)

  defp has_binding?(resource, candidate_path, %{__ash_bindings__: _} = query, type) do
    Enum.any?(query.__ash_bindings__.bindings, fn
      {_, %{path: path, source: source, type: ^type}} ->
        Ash.SatSolver.synonymous_relationship_paths?(resource, path, candidate_path, source)

      _ ->
        false
    end)
  end

  defp has_binding?(_, _, _, _), do: false

  defp get_binding(resource, path, %{__ash_bindings__: _} = query, type) do
    paths =
      Enum.flat_map(query.__ash_bindings__.bindings, fn
        {binding, %{path: path, type: ^type}} ->
          [{binding, path}]

        _ ->
          []
      end)

    Enum.find_value(paths, fn {binding, candidate_path} ->
      Ash.SatSolver.synonymous_relationship_paths?(resource, candidate_path, path) && binding
    end)
  end

  defp get_binding(_, _, _, _), do: nil

  defp add_distinct(relationship, join_type, joined_query) do
    if relationship.cardinality == :many and join_type == :left && !joined_query.distinct do
      from(row in joined_query,
        distinct: ^Ash.Resource.primary_key(relationship.destination)
      )
    else
      joined_query
    end
  end

  defp join_relationship(query, relationship, path, join_type, source) do
    case Map.get(query.__ash_bindings__.bindings, path) do
      %{type: existing_join_type} when join_type != existing_join_type ->
        raise "unreachable?"

      nil ->
        do_join_relationship(query, relationship, path, join_type, source)

      _ ->
        query
    end
  end

  defp do_join_relationship(query, %{type: :many_to_many} = relationship, path, kind, source) do
    relationship_through = maybe_get_resource_query(relationship.through)

    relationship_destination =
      Ecto.Queryable.to_query(maybe_get_resource_query(relationship.destination))

    current_binding =
      Enum.find_value(query.__ash_bindings__.bindings, 0, fn {binding, data} ->
        if data.type == kind && data.path == Enum.reverse(path) do
          binding
        end
      end)

    new_query =
      case kind do
        {:aggregate, _, subquery} ->
          subquery =
            subquery(
              from(destination in subquery,
                where:
                  field(destination, ^relationship.destination_field) ==
                    field(
                      parent_as(:rel_through),
                      ^relationship.destination_field_on_join_table
                    )
              )
            )

          from([{row, current_binding}] in query,
            left_join: through in ^relationship_through,
            as: :rel_through,
            on:
              field(row, ^relationship.source_field) ==
                field(through, ^relationship.source_field_on_join_table),
            left_lateral_join: destination in ^subquery,
            on:
              field(destination, ^relationship.destination_field) ==
                field(through, ^relationship.destination_field_on_join_table)
          )

        :inner ->
          from([{row, current_binding}] in query,
            join: through in ^relationship_through,
            on:
              field(row, ^relationship.source_field) ==
                field(through, ^relationship.source_field_on_join_table),
            join: destination in ^relationship_destination,
            on:
              field(destination, ^relationship.destination_field) ==
                field(through, ^relationship.destination_field_on_join_table)
          )

        _ ->
          from([{row, current_binding}] in query,
            left_join: through in ^relationship_through,
            on:
              field(row, ^relationship.source_field) ==
                field(through, ^relationship.source_field_on_join_table),
            left_join: destination in ^relationship_destination,
            on:
              field(destination, ^relationship.destination_field) ==
                field(through, ^relationship.destination_field_on_join_table)
          )
      end

    join_path =
      Enum.reverse([String.to_existing_atom(to_string(relationship.name) <> "_join_assoc") | path])

    full_path = Enum.reverse([relationship.name | path])

    binding_data =
      case kind do
        {:aggregate, name, _agg} ->
          %{type: :aggregate, name: name, path: full_path, source: source}

        _ ->
          %{type: kind, path: full_path, source: source}
      end

    new_query
    |> add_binding(%{path: join_path, type: :left, source: source})
    |> add_binding(binding_data)
  end

  defp do_join_relationship(query, relationship, path, kind, source) do
    relationship_destination =
      Ecto.Queryable.to_query(maybe_get_resource_query(relationship.destination))

    current_binding =
      Enum.find_value(query.__ash_bindings__.bindings, 0, fn {binding, data} ->
        if data.type == kind && data.path == Enum.reverse(path) do
          binding
        end
      end)

    new_query =
      case kind do
        {:aggregate, _, subquery} ->
          subquery =
            from(
              sub in subquery(
                from(destination in subquery,
                  where:
                    field(destination, ^relationship.destination_field) ==
                      field(parent_as(:rel_source), ^relationship.source_field)
                )
              ),
              select: field(sub, ^relationship.destination_field)
            )

          from([{row, current_binding}] in query,
            as: :rel_source,
            left_lateral_join: destination in ^subquery,
            on:
              field(row, ^relationship.source_field) ==
                field(destination, ^relationship.destination_field)
          )

        :inner ->
          from([{row, current_binding}] in query,
            join: destination in ^relationship_destination,
            on:
              field(row, ^relationship.source_field) ==
                field(destination, ^relationship.destination_field)
          )

        _ ->
          from([{row, current_binding}] in query,
            left_join: destination in ^relationship_destination,
            on:
              field(row, ^relationship.source_field) ==
                field(destination, ^relationship.destination_field)
          )
      end

    full_path = Enum.reverse([relationship.name | path])

    binding_data =
      case kind do
        {:aggregate, name, _agg} ->
          %{type: :aggregate, name: name, path: full_path, source: source}

        _ ->
          %{type: kind, path: full_path, source: source}
      end

    new_query
    |> add_binding(binding_data)
  end

  defp add_filter_expression(query, filter) do
    wheres =
      filter
      |> split_and_statements()
      |> Enum.map(fn filter ->
        {params, expr} = filter_to_expr(filter, query.__ash_bindings__.bindings, [])

        %Ecto.Query.BooleanExpr{
          expr: expr,
          op: :and,
          params: params
        }
      end)

    %{query | wheres: query.wheres ++ wheres}
  end

  defp split_and_statements(%Filter{expression: expression}) do
    split_and_statements(expression)
  end

  defp split_and_statements(%Expression{op: :and, left: left, right: right}) do
    split_and_statements(left) ++ split_and_statements(right)
  end

  defp split_and_statements(%Not{expression: %Not{expression: expression}}) do
    split_and_statements(expression)
  end

  defp split_and_statements(%Not{
         expression: %Expression{op: :or, left: left, right: right}
       }) do
    split_and_statements(%Expression{
      op: :and,
      left: %Not{expression: left},
      right: %Not{expression: right}
    })
  end

  defp split_and_statements(other), do: [other]

  defp filter_to_expr(%Filter{expression: expression}, bindings, params) do
    filter_to_expr(expression, bindings, params)
  end

  # A nil filter means "everything"
  defp filter_to_expr(nil, _, _), do: {[], true}
  # A true filter means "everything"
  defp filter_to_expr(true, _, _), do: {[], true}
  # A false filter means "nothing"
  defp filter_to_expr(false, _, _), do: {[], false}

  defp filter_to_expr(%Expression{op: op, left: left, right: right}, bindings, params) do
    {params, left_expr} = filter_to_expr(left, bindings, params)
    {params, right_expr} = filter_to_expr(right, bindings, params)
    {params, {op, [], [left_expr, right_expr]}}
  end

  defp filter_to_expr(%Not{expression: expression}, bindings, params) do
    {params, new_expression} = filter_to_expr(expression, bindings, params)
    {params, {:not, [], [new_expression]}}
  end

  defp filter_to_expr(
         %In{left: %Ref{} = left, right: map_set, embedded?: embedded?},
         bindings,
         params
       ) do
    simple_operator_expr(
      :in,
      params,
      MapSet.to_list(map_set),
      {:in, left.attribute.type},
      ref_binding(left, bindings),
      left.attribute,
      embedded?
    )
  end

  defp filter_to_expr(
         %IsNil{left: %Ref{} = left, right: nil?},
         bindings,
         params
       ) do
    if nil? do
      {params,
       {:is_nil, [],
        [{{:., [], [{:&, [], [ref_binding(left, bindings)]}, left.attribute.name]}, [], []}]}}
    else
      {params,
       {:not, [],
        [
          {:is_nil, [],
           [{{:., [], [{:&, [], [ref_binding(left, bindings)]}, left.attribute.name]}, [], []}]}
        ]}}
    end
  end

  defp filter_to_expr(
         %{operator: operator, left: %Ref{} = left, right: right, embedded?: embedded?},
         bindings,
         params
       ) do
    simple_operator_expr(
      operator,
      params,
      right,
      left.attribute.type,
      ref_binding(left, bindings),
      left.attribute,
      embedded?
    )
  end

  defp filter_to_expr(
         %TrigramSimilarity{arguments: [%Ref{} = ref, text, options], embedded?: false},
         bindings,
         params
       ) do
    param_count = Enum.count(params)

    case Enum.into(options, %{}) do
      %{equals: equals, greater_than: nil, less_than: nil} ->
        {params ++ [{text, :string}, {equals, :float}],
         {:fragment, [],
          [
            raw: "similarity(",
            expr:
              {{:., [], [{:&, [], [ref_binding(ref, bindings)]}, ref.attribute.name]}, [], []},
            raw: ", ",
            expr: {:^, [], [param_count]},
            raw: ") = ",
            expr: {:^, [], [param_count + 1]},
            raw: ""
          ]}}

      %{equals: nil, greater_than: greater_than, less_than: nil} ->
        {params ++ [{text, :string}, {greater_than, :float}],
         {:fragment, [],
          [
            raw: "similarity(",
            expr:
              {{:., [], [{:&, [], [ref_binding(ref, bindings)]}, ref.attribute.name]}, [], []},
            raw: ", ",
            expr: {:^, [], [param_count]},
            raw: ") > ",
            expr: {:^, [], [param_count + 1]},
            raw: ""
          ]}}

      %{equals: nil, greater_than: nil, less_than: less_than} ->
        {params ++ [{text, :string}, {less_than, :float}],
         {:fragment, [],
          [
            raw: "similarity(",
            expr:
              {{:., [], [{:&, [], [ref_binding(ref, bindings)]}, ref.attribute.name]}, [], []},
            raw: ", ",
            expr: {:^, [], [param_count]},
            raw: ") < ",
            expr: {:^, [], [param_count + 1]},
            raw: ""
          ]}}

      %{equals: nil, greater_than: greater_than, less_than: less_than} ->
        {params ++
           [{text, :string}, {less_than, :float}, {greater_than, :float}],
         {:fragment, [],
          [
            raw: "similarity(",
            expr:
              {{:., [], [{:&, [], [ref_binding(ref, bindings)]}, ref.attribute.name]}, [], []},
            raw: ", ",
            expr: {:^, [], [param_count]},
            raw: ") BETWEEN ",
            expr: {:^, [], [param_count + 1]},
            raw: " AND ",
            expr: {:^, [], [param_count + 2]},
            raw: ""
          ]}}
    end
  end

  defp filter_to_expr(
         %TrigramSimilarity{arguments: [%Ref{} = ref, text, options], embedded?: true},
         bindings,
         params
       ) do
    case Enum.into(options, %{}) do
      %{equals: equals, greater_than: nil, less_than: nil} ->
        {params,
         {:fragment, [],
          [
            raw: "similarity(",
            expr:
              {{:., [], [{:&, [], [ref_binding(ref, bindings)]}, ref.attribute.name]}, [], []},
            raw: ", ",
            expr: tagged(text, :string),
            raw: ") = ",
            expr: tagged(equals, :float),
            raw: ""
          ]}}

      %{equals: nil, greater_than: greater_than, less_than: nil} ->
        {params,
         {:fragment, [],
          [
            raw: "similarity(",
            expr:
              {{:., [], [{:&, [], [ref_binding(ref, bindings)]}, ref.attribute.name]}, [], []},
            raw: ", ",
            expr: tagged(text, :string),
            raw: ") > ",
            expr: tagged(greater_than, :float),
            raw: ""
          ]}}

      %{equals: nil, greater_than: nil, less_than: less_than} ->
        {params,
         {:fragment, [],
          [
            raw: "similarity(",
            expr:
              {{:., [], [{:&, [], [ref_binding(ref, bindings)]}, ref.attribute.name]}, [], []},
            raw: ", ",
            expr: tagged(text, :string),
            raw: ") < ",
            expr: tagged(less_than, :float),
            raw: ""
          ]}}

      %{equals: nil, greater_than: greater_than, less_than: less_than} ->
        {params,
         {:fragment, [],
          [
            raw: "similarity(",
            expr:
              {{:., [], [{:&, [], [ref_binding(ref, bindings)]}, ref.attribute.name]}, [], []},
            raw: ", ",
            expr: tagged(text, :string),
            raw: ") BETWEEN ",
            expr: tagged(less_than, :float),
            raw: " AND ",
            expr: tagged(greater_than, :float),
            raw: ""
          ]}}
    end
  end

  defp ref_binding(ref, bindings) do
    case ref.attribute do
      %Ash.Resource.Attribute{} ->
        Enum.find_value(bindings, fn {binding, data} ->
          data.path == ref.relationship_path && data.type in [:inner, :left, :root] && binding
        end)

      %Ash.Query.Aggregate{} = aggregate ->
        Enum.find_value(bindings, fn {binding, data} ->
          data.path == aggregate.relationship_path && data.type == :aggregate && binding
        end)
    end
  end

  defp simple_operator_expr(op, params, value, type, current_binding, attribute, false) do
    {params ++ [{value, op_type(type)}],
     {op, [],
      [
        {{:., [], [{:&, [], [current_binding]}, attribute.name]}, [], []},
        {:^, [], [Enum.count(params)]}
      ]}}
  end

  defp simple_operator_expr(op, params, value, type, current_binding, attribute, true) do
    {params,
     {op, [],
      [
        {{:., [], [{:&, [], [current_binding]}, attribute.name]}, [], []},
        tagged(value, type)
      ]}}
  end

  defp op_type({:in, type}) do
    {:in, op_type(type)}
  end

  defp op_type(type) do
    Ash.Type.ecto_type(type)
  end

  defp tagged(value, type) do
    %Ecto.Query.Tagged{value: value, type: get_type(type)}
  end

  defp get_type({:array, type}) do
    {:array, get_type(type)}
  end

  defp get_type(type) do
    if Ash.Type.ash_type?(type) do
      Ash.Type.storage_type(type)
    else
      type
    end
  end

  defp add_binding(query, data) do
    current = query.__ash_bindings__.current
    bindings = query.__ash_bindings__.bindings

    new_ash_bindings = %{
      query.__ash_bindings__
      | bindings: Map.put(bindings, current, data),
        current: current + 1
    }

    %{query | __ash_bindings__: new_ash_bindings}
  end

  @impl true
  def transaction(resource, func) do
    repo(resource).transaction(func)
  end

  @impl true
  def rollback(resource, term) do
    repo(resource).rollback(term)
  end

  defp maybe_get_resource_query(resource) do
    case Ash.Query.data_layer_query(Ash.Query.new(resource), only_validate_filter?: false) do
      {:ok, query} -> query
      {:error, error} -> {:error, error}
    end
  end
end