pub(all) enum AsyncOverflowPolicy {
  Blocking
  DropOldest
  DropNewest
}

pub(all) enum AsyncFlushPolicy {
  Never
  Batch
  Shutdown
}

pub enum AsyncRuntimeMode {
  NativeWorker
  Compatibility
}

pub fn async_runtime_mode_label(mode : AsyncRuntimeMode) -> String {
  match mode {
    AsyncRuntimeMode::NativeWorker => "native_worker"
    AsyncRuntimeMode::Compatibility => "compatibility"
  }
}

pub fn native_worker_async_runtime_mode() -> AsyncRuntimeMode {
  AsyncRuntimeMode::NativeWorker
}

pub fn compatibility_async_runtime_mode() -> AsyncRuntimeMode {
  AsyncRuntimeMode::Compatibility
}

pub struct AsyncRuntimeState {
  mode : AsyncRuntimeMode
  background_worker : Bool
}

pub fn AsyncRuntimeState::new(
  mode : AsyncRuntimeMode,
  background_worker : Bool,
) -> AsyncRuntimeState {
  { mode, background_worker }
}

pub struct AsyncLoggerState {
  runtime : AsyncRuntimeState
  pending_count : Int
  dropped_count : Int
  is_closed : Bool
  is_running : Bool
  has_failed : Bool
  last_error : String
  flush_policy : AsyncFlushPolicy
}

pub fn AsyncLoggerState::new(
  runtime : AsyncRuntimeState,
  pending_count : Int,
  dropped_count : Int,
  is_closed : Bool,
  is_running : Bool,
  has_failed : Bool,
  last_error : String,
  flush_policy : AsyncFlushPolicy,
) -> AsyncLoggerState {
  {
    runtime,
    pending_count,
    dropped_count,
    is_closed,
    is_running,
    has_failed,
    last_error,
    flush_policy,
  }
}

pub fn async_runtime_state_to_json(state : AsyncRuntimeState) -> @json_parser.JsonValue {
  @json_parser.JsonValue::Object({
    "mode": @json_parser.JsonValue::String(async_runtime_mode_label(state.mode)),
    "background_worker": @json_parser.JsonValue::Bool(state.background_worker),
  })
}

pub fn stringify_async_runtime_state(
  state : AsyncRuntimeState,
  pretty~ : Bool = false,
) -> String {
  let value = async_runtime_state_to_json(state)
  if pretty {
    @json_parser.stringify_pretty(value, 2)
  } else {
    @json_parser.stringify(value)
  }
}

fn async_flush_policy_label(policy : AsyncFlushPolicy) -> String {
  match policy {
    AsyncFlushPolicy::Never => "Never"
    AsyncFlushPolicy::Batch => "Batch"
    AsyncFlushPolicy::Shutdown => "Shutdown"
  }
}

fn async_logger_state_to_json_value(state : AsyncLoggerState) -> @json_parser.JsonValue {
  @json_parser.JsonValue::Object({
    "runtime": async_runtime_state_to_json(state.runtime),
    "pending_count": @json_parser.JsonValue::Number(state.pending_count.to_double()),
    "dropped_count": @json_parser.JsonValue::Number(state.dropped_count.to_double()),
    "is_closed": @json_parser.JsonValue::Bool(state.is_closed),
    "is_running": @json_parser.JsonValue::Bool(state.is_running),
    "has_failed": @json_parser.JsonValue::Bool(state.has_failed),
    "last_error": @json_parser.JsonValue::String(state.last_error),
    "flush_policy": @json_parser.JsonValue::String(async_flush_policy_label(state.flush_policy)),
  })
}

pub fn async_logger_state_to_json(state : AsyncLoggerState) -> @json_parser.JsonValue {
  async_logger_state_to_json_value(state)
}

pub fn stringify_async_logger_state(
  state : AsyncLoggerState,
  pretty~ : Bool = false,
) -> String {
  let value = async_logger_state_to_json_value(state)
  if pretty {
    @json_parser.stringify_pretty(value, 2)
  } else {
    @json_parser.stringify(value)
  }
}

pub struct AsyncLoggerConfig {
  max_pending : Int
  overflow : AsyncOverflowPolicy
  max_batch : Int
  linger_ms : Int
  flush : AsyncFlushPolicy
}

pub fn AsyncLoggerConfig::new(
  max_pending~ : Int = 0,
  overflow~ : AsyncOverflowPolicy = AsyncOverflowPolicy::Blocking,
  max_batch~ : Int = 1,
  linger_ms~ : Int = 0,
  flush~ : AsyncFlushPolicy = AsyncFlushPolicy::Never,
) -> AsyncLoggerConfig {
  {
    max_pending,
    overflow,
    max_batch: if max_batch <= 1 { 1 } else { max_batch },
    linger_ms: if linger_ms < 0 { 0 } else { linger_ms },
    flush,
  }
}

fn parse_async_overflow(name : String) -> AsyncOverflowPolicy raise {
  match name.to_upper() {
    "BLOCKING" => AsyncOverflowPolicy::Blocking
    "DROPOLDEST" => AsyncOverflowPolicy::DropOldest
    "DROPLATEST" => AsyncOverflowPolicy::DropNewest
    "DROPNEWEST" => AsyncOverflowPolicy::DropNewest
    _ => raise Failure::Failure("Unsupported async overflow policy: " + name)
  }
}

fn parse_async_flush(name : String) -> AsyncFlushPolicy raise {
  match name.to_upper() {
    "NEVER" => AsyncFlushPolicy::Never
    "NONE" => AsyncFlushPolicy::Never
    "BATCH" => AsyncFlushPolicy::Batch
    "SHUTDOWN" => AsyncFlushPolicy::Shutdown
    _ => raise Failure::Failure("Unsupported async flush policy: " + name)
  }
}

pub fn parse_async_logger_config_text(input : String) -> AsyncLoggerConfig raise {
  let root = @json_parser.parse(input)
  let obj = match root.as_object() {
    Some(obj) => obj
    None => raise Failure::Failure("Expected object for async logger config")
  }
  let max_pending = match obj.get("max_pending") {
    Some(value) => match value.as_number() {
      Some(number) => number.to_int()
      None => raise Failure::Failure("Expected number at async_config.max_pending")
    }
    None => 0
  }
  let overflow = match obj.get("overflow") {
    Some(value) => match value.as_string() {
      Some(text) => parse_async_overflow(text)
      None => raise Failure::Failure("Expected string at async_config.overflow")
    }
    None => AsyncOverflowPolicy::Blocking
  }
  let max_batch = match obj.get("max_batch") {
    Some(value) => match value.as_number() {
      Some(number) => number.to_int()
      None => raise Failure::Failure("Expected number at async_config.max_batch")
    }
    None => 1
  }
  let linger_ms = match obj.get("linger_ms") {
    Some(value) => match value.as_number() {
      Some(number) => number.to_int()
      None => raise Failure::Failure("Expected number at async_config.linger_ms")
    }
    None => 0
  }
  let flush = match obj.get("flush") {
    Some(value) => match value.as_string() {
      Some(text) => parse_async_flush(text)
      None => raise Failure::Failure("Expected string at async_config.flush")
    }
    None => AsyncFlushPolicy::Never
  }
  AsyncLoggerConfig::new(
    max_pending=max_pending,
    overflow=overflow,
    max_batch=max_batch,
    linger_ms=linger_ms,
    flush=flush,
  )
}

pub fn async_logger_config_to_json(config : AsyncLoggerConfig) -> @json_parser.JsonValue {
  @json_parser.JsonValue::Object({
    "max_pending": @json_parser.JsonValue::Number(config.max_pending.to_double()),
    "max_batch": @json_parser.JsonValue::Number(config.max_batch.to_double()),
    "linger_ms": @json_parser.JsonValue::Number(config.linger_ms.to_double()),
    "overflow": @json_parser.JsonValue::String(match config.overflow {
      AsyncOverflowPolicy::Blocking => "Blocking"
      AsyncOverflowPolicy::DropOldest => "DropOldest"
      AsyncOverflowPolicy::DropNewest => "DropNewest"
    }),
    "flush": @json_parser.JsonValue::String(match config.flush {
      AsyncFlushPolicy::Never => "Never"
      AsyncFlushPolicy::Batch => "Batch"
      AsyncFlushPolicy::Shutdown => "Shutdown"
    }),
  })
}

pub fn stringify_async_logger_config(config : AsyncLoggerConfig, pretty~ : Bool = false) -> String {
  let value = async_logger_config_to_json(config)
  if pretty {
    @json_parser.stringify_pretty(value, 2)
  } else {
    @json_parser.stringify(value)
  }
}

pub struct AsyncLoggerBuildConfig {
  logger : @bitlogger.LoggerConfig
  async_config : AsyncLoggerConfig
}

pub fn AsyncLoggerBuildConfig::new(
  logger~ : @bitlogger.LoggerConfig = @bitlogger.default_logger_config(),
  async_config~ : AsyncLoggerConfig = AsyncLoggerConfig::new(),
) -> AsyncLoggerBuildConfig {
  { logger, async_config }
}

pub fn parse_async_logger_build_config_text(input : String) -> AsyncLoggerBuildConfig raise {
  let root = @json_parser.parse(input)
  let obj = match root.as_object() {
    Some(obj) => obj
    None => raise Failure::Failure("Expected object at async logger build config root")
  }
  let logger = match obj.get("logger") {
    Some(value) => @bitlogger.parse_logger_config_text(@json_parser.stringify(value))
    None => @bitlogger.default_logger_config()
  }
  let async_config = match obj.get("async_config") {
    Some(value) => parse_async_logger_config_text(@json_parser.stringify(value))
    None => AsyncLoggerConfig::new()
  }
  AsyncLoggerBuildConfig::new(logger=logger, async_config=async_config)
}

pub fn async_logger_build_config_to_json(
  config : AsyncLoggerBuildConfig,
) -> @json_parser.JsonValue {
  @json_parser.JsonValue::Object({
    "logger": @bitlogger.logger_config_to_json(config.logger),
    "async_config": async_logger_config_to_json(config.async_config),
  })
}

pub fn stringify_async_logger_build_config(
  config : AsyncLoggerBuildConfig,
  pretty~ : Bool = false,
) -> String {
  let value = async_logger_build_config_to_json(config)
  if pretty {
    @json_parser.stringify_pretty(value, 2)
  } else {
    @json_parser.stringify(value)
  }
}