;;; Guix Data Service -- Information about Guix over time
;;; Copyright © 2019 Christopher Baines <mail@cbaines.net>
;;;
;;; This program is free software: you can redistribute it and/or
;;; modify it under the terms of the GNU Affero General Public License
;;; as published by the Free Software Foundation, either version 3 of
;;; the License, or (at your option) any later version.
;;;
;;; This program is distributed in the hope that it will be useful,
;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
;;; Affero General Public License for more details.
;;;
;;; You should have received a copy of the GNU Affero General Public
;;; License along with this program.  If not, see
;;; <http://www.gnu.org/licenses/>.

(define-module (guix-data-service model git-repository)
  #:use-module (ice-9 match)
  #:use-module (json)
  #:use-module (squee)
  #:export (all-git-repositories
            select-git-repository
            git-repository-id->url
            git-repository-url->git-repository-id
            git-repositories-containing-commit

            guix-revisions-and-jobs-for-git-repository))

(define (all-git-repositories conn)
  (map
   (match-lambda
     ((id label url cgit-base-url)
      (list (string->number id)
            label
            url
            cgit-base-url)))
   (exec-query
    conn
    (string-append
     "SELECT id, label, url, cgit_url_base FROM git_repositories ORDER BY id ASC"))))

(define (select-git-repository conn id)
  (match (exec-query
          conn
          "SELECT label, url, cgit_url_base FROM git_repositories WHERE id = $1"
          (list id))
    (()
     #f)
    ((result)
     result)))

(define (git-repository-id->url conn id)
  (match
      (exec-query
       conn
       (string-append
        "SELECT url FROM git_repositories WHERE id = $1;")
       (list id))
    (((url)) url)))

(define (git-repository-url->git-repository-id conn url)
  (let ((existing-id
         (exec-query
          conn
          (string-append
           "SELECT id FROM git_repositories WHERE url = '" url "'"))))
    (string->number
     (match existing-id
       (((id)) id)
       (()
        (caar
         (exec-query conn
                     (string-append
                      "INSERT INTO git_repositories "
                      "(url) "
                      "VALUES "
                      "('" url "') "
                      "RETURNING id"))))))))

(define (guix-revisions-and-jobs-for-git-repository conn git-repository-id)
  (define query
    "
SELECT NULL AS id, load_new_guix_revision_jobs.id AS job_id,
  (
    SELECT json_agg(event)
    FROM load_new_guix_revision_job_events
    WHERE load_new_guix_revision_jobs.id = load_new_guix_revision_job_events.job_id
  ) AS job_events, commit, source
FROM load_new_guix_revision_jobs
WHERE git_repository_id = $1 AND succeeded_at IS NULL AND NOT EXISTS (
  SELECT 1 FROM load_new_guix_revision_job_events
  WHERE event = 'failure' AND job_id = load_new_guix_revision_jobs.id
)
UNION ALL
SELECT id, NULL, NULL, commit, NULL
FROM guix_revisions
WHERE git_repository_id = $1
ORDER BY 1 DESC NULLS FIRST, 2 DESC LIMIT 10;")

  (map
   (match-lambda
     ((id job_id job_events commit source)
      (list id
            job_id
            (if (string=? "" job_events)
                '()
                (vector->list (json-string->scm job_events)))
            commit source)))
   (exec-query
    conn
    query
    (list git-repository-id))))

(define (git-repositories-containing-commit conn commit)
  (define query
    "
SELECT id, label, url, cgit_url_base
FROM git_repositories WHERE id IN (
  SELECT git_repository_id
  FROM git_branches
  WHERE commit = $1
)")

  (exec-query conn query (list commit)))