(*

Module: Channels

  Parses channels.conf files

Author: Raphael Pinson <raphink@gmail.com>

About: Reference

  See http://linuxtv.org/vdrwiki/index.php/Syntax_of_channels.conf

About: License

   This file is licenced under the LGPL v2+, like the rest of Augeas.

About: Lens Usage

   To be documented

About: Configuration files

   This lens applies to channels.conf files.

About: Examples

   The <Test_Channels> file contains various examples and tests.

*)

module Channels =

(************************************************************************

 * Group:                 USEFUL PRIMITIVES

 *************************************************************************)

(* View: eol *)

let eol = Util.eol

(* View: comment *)

let comment = Util.comment_generic /;[ \t]*/ "; "

(* View: equal *)

let equal = Sep.equal

(* View: colon *)

let colon = Sep.colon

(* View: comma *)

let comma = Sep.comma

(* View: semicol *)

let semicol = Util.del_str ";"

(* View: plus *)

let plus = Util.del_str "+"

(* View: arroba *)

let arroba = Util.del_str "@"

(* View: no_colon *)

let no_colon = /[^: \t\n][^:\n]*[^: \t\n]|[^:\n]/

(* View: no_semicolon *)

let no_semicolon = /[^;\n]+/

(************************************************************************

 * Group:                 FUNCTIONS

 *************************************************************************)

(* View: field

   A generic field *)

let field (name:string) (sto:regexp) = [ label name . store sto ]

(* View: field_no_colon

   A <field> storing <no_colon> *)

let field_no_colon (name:string) = field name no_colon

(* View: field_int

   A <field> storing <Rx.integer> *)

let field_int (name:string) = field name Rx.integer

(* View: field_word

   A <field> storing <Rx.word> *)

let field_word (name:string) = field name Rx.word

(************************************************************************

 * Group:                 ENTRIES

 *************************************************************************)

(* View: vpid *)

let vpid =

   let codec = 

           [ equal . label "codec" . store Rx.integer ]

   in let vpid_entry (lbl:string) =

           [ label lbl . store Rx.integer . codec? ]

   in vpid_entry "vpid"

    . ( plus . vpid_entry "vpid_pcr" )?

(* View: langs *)

let langs =

   let lang =

           [ label "lang" . store Rx.word ]

   in Build.opt_list lang plus

(* View: apid *)

let apid =

   let codec =

           [ arroba . label "codec" . store Rx.integer ]

   in let options =

           equal . ( (langs . codec?) | codec )

   in let apid_entry (lbl:string) =

           [ label lbl . store Rx.integer . options? ]

   in Build.opt_list (apid_entry "apid") comma

    . ( semicol

      . Build.opt_list (apid_entry "apid_dolby") comma )?

(* View: tpid *)

let tpid =

   let tpid_bylang =

           [ label "tpid_bylang" . store Rx.integer

           . (equal . langs)? ]

   in field_int "tpid"

      . ( semicol . Build.opt_list tpid_bylang comma )?

(* View: caid *)

let caid =

   let caid_entry =

           [ label "caid" . store Rx.word ]

   in Build.opt_list caid_entry comma

(* View: entry *)

let entry = [ label "entry" . store no_semicolon

             . (semicol . field_no_colon "provider")? . colon

             . field_int "frequency" . colon

             . field_word "parameter" . colon

             . field_word "signal_source" . colon

             . field_int "symbol_rate" . colon

             . vpid . colon

             . apid . colon

             . tpid . colon

             . caid . colon

             . field_int "sid" . colon

             . field_int "nid" . colon

             . field_int "tid" . colon

             . field_int "rid" . eol ]

(* View: entry_or_comment *)

let entry_or_comment = entry | comment

(* View: group *)

let group =

      [ Util.del_str ":" . label "group"

      . store no_colon . eol

      . entry_or_comment* ]

(* View: lns *)

let lns = entry_or_comment* . group*