pub(all) suberror TideError {
  TideError(String)
} derive(Eq)

pub(all) enum Command {
  Transact(id~ : String, changes~ : Array[Mutation])
  Advance(id~ : String, to~ : Int)
  Forget(id~ : String, to~ : Int)
} derive(Eq)

pub(all) struct Config {
  window : WindowSpec
  lateness : Int
  max_events : Int
  max_operations : Int
  trigger : Trigger
  value_field : String?
} derive(Eq)

pub(all) struct Delta {
  kind : String
  before : Window?
  after : Window?
} derive(Eq, ToJson)

pub struct Engine {
  cfg : Config
  records : Map[String, Event]
  frozen : Map[String, Event]
  materialized : Array[Window]
  clock : Int
  revision : Int
  committed : Map[String, Command]
  journal : Array[Command]
  journal_units : Int
}

pub(all) struct Event {
  id : String
  key : String
  at : Int
  value : Int
  fields : Array[(String, String)]?
} derive(Eq)

pub(all) struct Measure {
  name : String
  identity : Int64
  step : (Int64, Int64) -> Int64
  finish : (Int64, Int64) -> Int64
}

pub(all) struct MeasureResult {
  name : String
  value : Int64
} derive(Eq, ToJson)

pub(all) struct MeasureWindow {
  key : String
  start : Int
  end : Int
  count : Int
  measures : Array[MeasureResult]
  phase : String
} derive(Eq, ToJson)

pub(all) enum Mutation {
  Put(Event)
  Remove(String)
} derive(Eq)

pub(all) struct Outcome {
  id : String
  status : String
  version : Int
  watermark : Int
  deltas : Array[Delta]
  message : String
} derive(Eq, ToJson)

pub(all) struct Replay {
  schema_version : Int
  config : Config
  steps : Array[Outcome]
  rows : Array[Window]
  events : Array[Event]
  frozen : Int
  watermark : Int
  version : Int
  checkpoint : Json
} derive(ToJson)

pub(all) enum Trigger {
  Watermark
  Count(threshold~ : Int)
} derive(Eq)

pub struct View {
  materialized : Array[Window]
  revision : Int
  clock : Int
  last_delivery : String
}

pub struct WatermarkTracker {
  max_time : Int
  allowed_lateness : Int
}

pub(all) struct Window {
  key : String
  start : Int
  end : Int
  count : Int
  sum : Int64
  min : Int
  max : Int
  members : Array[String]
  phase : String
} derive(Eq, ToJson)

pub(all) enum WindowSpec {
  Tumbling(size~ : Int, offset~ : Int)
  Sliding(size~ : Int, slide~ : Int, offset~ : Int)
  Session(gap~ : Int)
} derive(Eq)

fn aggregate(c : Config, events : Array[Event], watermark? : Int) -> Array[Window] raise TideError

fn assign_fixed(spec : WindowSpec, at : Int) -> Array[(Int, Int)] raise TideError

fn average_measure() -> Measure

fn config(window : WindowSpec, lateness? : Int, max_events? : Int, max_operations? : Int, trigger? : Trigger, value_field? : String?) -> Config raise TideError

fn count_measure() -> Measure

fn decode_commands(source : String) -> Array[Command] raise TideError

fn decode_config(source : String) -> Config raise TideError

fn max_measure() -> Measure

fn measure(name~ : String, identity~ : Int64, step~ : (Int64, Int64) -> Int64, finish~ : (Int64, Int64) -> Int64) -> Measure

fn measure_window(c : Config, events : Array[Event], measures : Array[Measure], watermark? : Int) -> Array[MeasureWindow] raise TideError

fn min_measure() -> Measure

fn replay(c : Config, commands : Array[Command]) -> Replay raise TideError

fn replay_json(source : String) -> String raise TideError

fn restore(source : String) -> Engine raise TideError

fn resume_json(source : String) -> String raise TideError

fn stream_json(source : String) -> String raise TideError

fn sum_measure() -> Measure

fn validate_event(e : Event) -> Unit raise TideError