(ns Process
  "Elixir Process module — BEAM process management.

   In CljElixir: (Process/sleep 1000), (Process/send pid msg), etc.
   Provides utilities for working with BEAM processes (lightweight actors).")

(defn sleep
  "Sleeps the current process for `timeout` milliseconds or :infinity.
   (Process/sleep 1000) ;=> :ok (sleeps 1 second)
   (Process/sleep :infinity) ;=> blocks forever"
  [timeout])

(defn send
  "Sends `msg` to `dest` (pid, port, or registered name). Returns `msg`.
   (Process/send pid {:hello \"world\"})
   (Process/send pid msg [:noconnect]) ;=> with options"
  ([dest msg])
  ([dest msg opts]))

(defn spawn
  "Spawns a new process. Returns the PID.
   (Process/spawn (fn [] (IO/puts \"hi\")) [])
   (Process/spawn MyModule :my-func [arg1 arg2] [:link])"
  ([fun opts])
  ([module function args opts]))

(defn spawn-link
  "Spawns a linked process. If the child crashes, the parent crashes too.
   (Process/spawn-link (fn [] (IO/puts \"linked\")) [])"
  ([fun opts])
  ([module function args opts]))

(defn spawn-monitor
  "Spawns a monitored process. Returns {pid, ref}.
   (Process/spawn-monitor (fn [] (do-work)))"
  ([fun])
  ([module function args]))

(defn alive?
  "Returns true if the process identified by `pid` is alive.
   (Process/alive? pid) ;=> true"
  [pid])

(defn self
  "Returns the PID of the calling process.
   (Process/self) ;=> #PID<0.123.0>"
  [])

(defn whereis
  "Returns the PID registered under `name`, or nil.
   (Process/whereis :my-server) ;=> #PID<0.456.0>"
  [name])

(defn register
  "Registers a PID under the given atom `name`.
   (Process/register pid :my-server) ;=> true"
  [pid name])

(defn unregister
  "Unregisters the given `name`.
   (Process/unregister :my-server) ;=> true"
  [name])

(defn registered
  "Returns a list of all registered process names.
   (Process/registered) ;=> [:logger :code-server ...]"
  [])

(defn link
  "Creates a link between the calling process and `pid_or_port`.
   (Process/link pid)"
  [pid-or-port])

(defn unlink
  "Removes a link between the calling process and `pid_or_port`.
   (Process/unlink pid)"
  [pid-or-port])

(defn monitor
  "Starts monitoring `item`. Returns a reference.
   (Process/monitor :process pid)"
  ([type item])
  ([type item opts]))

(defn demonitor
  "Stops monitoring. The `ref` is from a previous `monitor` call.
   (Process/demonitor ref)
   (Process/demonitor ref [:flush])"
  ([ref])
  ([ref opts]))

(defn exit
  "Sends an exit signal to `pid`.
   (Process/exit pid :normal) ;=> normal shutdown
   (Process/exit pid :kill) ;=> forceful kill (untrappable)"
  [pid reason])

(defn flag
  "Sets process flags. Returns the old value.
   (Process/flag :trap-exit true) ;=> false (previous value)
   (Process/flag :priority :high)"
  ([flag value])
  ([pid flag value]))

(defn info
  "Returns info about a process.
   (Process/info pid) ;=> keyword list of process info
   (Process/info pid :message-queue-len) ;=> message queue length"
  ([pid])
  ([pid item]))

(defn list
  "Returns a list of all running process PIDs.
   (Process/list) ;=> [#PID<0.0.0> #PID<0.1.0> ...]"
  [])

(defn group-leader
  "Returns or sets the group leader.
   (Process/group-leader) ;=> #PID<0.64.0>
   (Process/group-leader pid gl)"
  ([])
  ([pid leader]))

(defn hibernate
  "Puts the process into hibernation (frees memory). Resumes in `fun`.
   (Process/hibernate Module :function [args])"
  [module function args])

(defn send-after
  "Sends `msg` to `dest` after `time` milliseconds. Returns a timer ref.
   (Process/send-after self :tick 1000)"
  ([dest msg time])
  ([dest msg time opts]))

(defn cancel-timer
  "Cancels a timer created by send-after."
  ([timer-ref])
  ([timer-ref opts]))

(defn read-timer
  "Returns the time remaining for a timer, or false."
  ([timer-ref])
  ([timer-ref opts]))

(defn put
  "Puts a key-value pair in the process dictionary. Returns old value or nil.
   (Process/put :my-key \"my value\") ;=> nil"
  [key value])

(defn get
  "Gets a value from the process dictionary.
   (Process/get :my-key) ;=> \"my value\"
   (Process/get :missing :default) ;=> :default"
  ([key])
  ([key default]))

(defn delete
  "Deletes a key from the process dictionary. Returns old value.
   (Process/delete :my-key) ;=> \"my value\""
  [key])

(defn get-keys
  "Returns all keys in the process dictionary (or keys with given value).
   (Process/get-keys) ;=> [:my-key ...]"
  ([])
  ([value]))