(* Perform a complete Fedora OCaml rebuild, in build order. *)

open Unix
open Printf

open Goaljobs
open Config
open Git
open Fedora

let branch = "master"
let koji_target = "rawhide"

(* The name of the rebuild, and also the magic substring that must
 * appear in the %changelog when the package has been rebuilt.
 *)
let rebuild_name = "ocaml-4.02.1"

(* Local repository that contains build dependencies. *)
let yum_repo = "koji-rawhide"

(* Packages that have problems.  These block the packages and all
 * dependent packages.
 *)
let blocked = [
  "ocaml-pa-do";                        (* orphaned *)
  "plplot";                             (* FTBFS, unrelated to OCaml *)
]
let blocked pkg = List.mem pkg blocked

(* These packages are treated as if they have been rebuilt. *)
let ignored = [
  "ocaml-srpm-macros";             (* don't need to build this *)
  "ocaml";                         (* rebuilt by hand *)
  "whenjobs";                      (* obsolete *)
]
let ignored pkg = List.mem pkg ignored

(* List of OCaml-related source package names. *)
let source_packages =
  let dirs = shlines "cd %s && ls -1d ocaml*" fedora_dir in
  dirs @ [ "alt-ergo"; "apron"; "brltty"; "coccinelle"; "coq";
           "cduce"; "frama-c"; "gappalib-coq"; "graphviz"; "hevea"; "hivex";
           "js-of-ocaml"; "plplot"; "virt-top"; "why3";
           "flocq" (* no OCaml code, but needs to be rebuilt after Coq *);
           "guestfs-browser"; "libguestfs";
           "virt-dmesg" ]

(* Dependencies of each package.  (pkg, [deps ...]) *)
let pkg_deps = dependencies branch source_packages

(* Remove blocked packages and packages which have a blocked package
 * as a dependency (recursively).
 *)
let source_packages =
  let rec is_blocked pkg =
    if blocked pkg then true
    else (
      let deps = List.assoc pkg pkg_deps in
      List.exists is_blocked deps
    )
  in
  List.filter (fun pkg -> not (is_blocked pkg)) source_packages

(* Short the dependencies lists so that the build order is stable
 * each time it runs.
 *)
let pkg_deps =
  List.map (fun (pkg, deps) -> pkg, List.sort compare deps) pkg_deps

(* Sort the source packages so that the packages with the largest
 * number of reverse dependencies [other packages that depend on it]
 * appear earlier in the list, on the basis that building these
 * packages first has the greatest advantage.
 *)
let source_packages =
  let rdeps pkg =
    Utils.filter_map (
      fun (rdep, deps) -> if List.mem pkg deps then Some rdep else None
    ) pkg_deps
  in
  let cmp p1 p2 =
    let r1 = rdeps p1 and r2 = rdeps p2 in
    let n1 = List.length r1 and n2 = List.length r2 in
    if n1 <> n2 then compare n2 n1 else compare p1 p2
  in
  List.sort cmp source_packages

let () =
  printf "final list of source packages = %s\n%!"
    (String.concat " " source_packages)

(* We could make this a goal, but it's cheap enough to run it unconditionally. *)
let install_build_dependencies pkg =
  sh "sudo yum clean all --disablerepo=\\* --enablerepo=%s"
    (quote yum_repo);
  sh "sudo yum-builddep -y --disablerepo=\\* --enablerepo=%s %s"
    (quote yum_repo) (fedora_specfile pkg branch)

(* Unset MAKEFLAGS so it doesn't affect local builds. *)
let () = Unix.putenv "MAKEFLAGS" ""

(* Goal: rebuild all packages. *)
let rec goal all () =
  let n = List.length source_packages in
  List.iteri (
    fun i pkg ->
      require (rebuild_started pkg);
      printf "*** *** rebuilt %d/%d packages *** ***\n%!" (i+1) n
  ) source_packages

(* Goal: That 'package' has been rebuilt and exists in Koji. *)
and rebuilt pkg =
  let specfile = fedora_specfile pkg branch in

  (* Note: verrel may change as we go along, so don't assign it to
   * variable.
   *)

  (* Note the target must be both of these because the old verrel
   * could exist as a koji build without it having been part of the
   * rebuild.
   *)
  target (ignored pkg ||
            (file_contains_string specfile rebuild_name &&
               koji_build_state (fedora_verrel pkg branch) == `Complete));

  (* Ignored packages are treated as if they have been rebuilt. *)
  if not (ignored pkg) then (

    (* Start the rebuild. *)
    require (rebuild_started pkg);

    (* Wait for the build state to reach a conclusion. *)
    let rec loop () =
      match koji_build_state (fedora_verrel pkg branch) with
      | `No_such_build ->
        failwith (sprintf "rebuild of package %s: no build found" pkg)
      | `Building ->
        sleep 60;
        loop ()
      | `Complete ->
        ()
      | `Deleted ->
        failwith (sprintf "rebuild of package %s: deleted" pkg)
      | `Failed ->
        failwith (sprintf "rebuild of package %s: failed" pkg)
      | `Canceled ->
        failwith (sprintf "rebuild of package %s: canceled" pkg)
    in
    loop ();

    (* Wait for the build to appear in Koji repo. *)
    koji_wait_repo koji_target (fedora_verrel pkg branch)
  )

(* Goal: The rebuild of the package has started, but we haven't waited
 * for it to finish.
 *)
and rebuild_started pkg =
  let deps = List.assoc pkg pkg_deps in
  let specfile = fedora_specfile pkg branch in

  (* Note the target must be both of these because the old verrel
   * could exist as a koji build without it having been part of the
   * rebuild.
   *)
  target (ignored pkg ||
            (file_contains_string specfile rebuild_name &&
               (match koji_build_state (fedora_verrel pkg branch) with
               | `Building | `Complete -> true
               | `Deleted | `Failed | `Canceled | `No_such_build -> false)));

  (* All dependent packages must have been fully rebuilt and in the
   * repo first.
   *)
  List.iter (fun dep -> require (rebuilt dep)) deps;

  (* Ignored packages are treated as if they have been rebuilt. *)
  if not (ignored pkg) then (
(*
    (* A local test build must succeed. *)
    require (local_build_succeeded pkg);
*)
    (* local_build_succeeded normally does this ... *)
    require (specfile_updated pkg);

    (* Rebuild the package in Koji.  Don't wait ... *)
    koji_build ~wait:false pkg branch;

    (* ... but the build doesn't appear in Koji (eg. in 'koji
     * buildinfo') until the SRPM has been built.  This can take quite
     * some time.  Loop here until the build appears.
     *)
    let rec loop () =
      match koji_build_state (fedora_verrel pkg branch) with
      | `No_such_build ->
        sleep 60;
        loop ();
      | `Building | `Complete ->
        ()
      | `Deleted ->
        failwith (sprintf "rebuild of package %s: deleted" pkg)
      | `Failed ->
        failwith (sprintf "rebuild of package %s: failed" pkg)
      | `Canceled ->
        failwith (sprintf "rebuild of package %s: canceled" pkg)
    in
    loop ()
  )

(*
and local_build_succeeded pkg =
  (* The specfile must have been updated. *)
  require (specfile_updated pkg);

  let key =
    sprintf "fedora_ocaml_local_build_%s_%s" pkg (fedora_verrel pkg branch) in

  target (memory_exists key);

  install_build_dependencies pkg;

 (* Do a local test build to ensure the Koji build will work. *)
  sh "
    cd %s
     fedpkg local
  " (fedora_repo pkg branch);

  memory_set key "1"
*)

and specfile_updated pkg =
  let repodir = fedora_repo pkg branch in
  let specfile = fedora_specfile pkg branch in

  sh "
    cd %s
    rm -rf x86_64 noarch *.src.rpm .build* clog
    git fetch
  " repodir;

  if not (git_has_local_changes repodir) then
    sh "
      cd %s
      git pull --rebase
    " repodir;

(* - XXX why did we do this here?
  install_build_dependencies pkg;
*)

  (* For rationale behind always bumping the spec file, see comment
   * in 'fedora.ml'.
   *)
  let title =
    if not (file_contains_string specfile rebuild_name) then
      rebuild_name ^ " rebuild."
    else
      "Bump release and rebuild." in
  sh "rpmdev-bumpspec -c %s %s" (quote title) specfile;

  (* XXX Automate common specfile fixes. *)

  sh "
    cd %s
    fedpkg commit -c
    fedpkg push
  " repodir