(define-module (services)
  #:use-module ((ice-9 popen) #:prefix popen:)
  #:use-module ((ice-9 textual-ports) #:prefix textual-ports:)
  #:use-module ((gnu build linux-container) #:prefix container:)
  #:use-module ((srfi srfi-1) #:prefix srfi-1:)
  #:use-module ((xyz euandreh heredoc) #:prefix heredoc:)
  #:use-module (gnu)
  #:use-module (guix build utils)
  #:use-module (guix least-authority)
  #:use-module (guix records))
(use-package-modules
  admin)
(use-service-modules
  admin
  mcron
  shepherd)
(heredoc:enable-syntax)


(define +working-dir+
  (if (directory-exists? "/opt/deploy/current")
    "/opt/deploy/current"
    (canonicalize-path ".")))

(add-to-load-path
 (string-append +working-dir+ "/src/infrastructure/guix"))
(use-modules
  ((packages) #:prefix packages:))



(define-record-type* <papo-configuration>
  papo-configuration
  make-papo-configuration
  papo-configuration?
  (package              papo-configuration-package              (default packages:papo))
  (user                 papo-configuration-user                 (default "papo"))
  (group                papo-configuration-group                (default "papo"))
  (config-dirname       papo-configuration-config               (default "papo"))
  (port                 papo-configuration-port                 (default 6666))
  (log-file             papo-configuration-log-file             (default "/var/log/papo.log"))
  (data-directory       papo-configuration-data-directory       (default "/var/lib/papo"))
  (run-directory        papo-configuration-run-directory        (default "/var/run/papo"))
  (run-in-container?    papo-configuration-run-in-container?    (default #t))
  (container-name       papo-configuration-container-name       (default "papo-container"))
  (container-namespaces papo-configuration-container-namespaces (default container:%namespaces))
  (extra-mappings       papo-configuration-extra-mappings       (default '())))

(define (papo-etc-files config)
  (match-record config <papo-configuration>
      ()
    `(("papo.json" ,(plain-file "papo.json" "")))))

(define (papo-log-rotations config)
  (match-record config <papo-configuration>
      (log-file)
    (list
      (log-rotation
        (frequency 'weekly)
        (files (list log-file))
        (options '("rotate 5200"))))))

(define (papo-activation config)
  (match-record config <papo-configuration>
      (user log-file data-directory run-directory)
    #~(begin
        (use-modules (guix build utils))
        (format (current-error-port)
         "Creating papo log directory for '~a'.~%" #$log-file)
        (mkdir-p (dirname #$log-file))
        (when (not (file-exists? #$log-file))
          (call-with-output-file #$log-file (const #t)))
        (chmod #$log-file #o644)
        (let ((user (getpwnam #$user)))
          (format (current-error-port)
           "Creating papo data directory '~a'.~%" #$data-directory)
          (mkdir-p #$data-directory)
          (chown #$data-directory (passwd:uid user) (passwd:gid user))
          (chmod #$data-directory #o750)
          (format (current-error-port)
           "Creating papo run directory '~a'.~%" #$run-directory)
          (mkdir-p #$run-directory)
          (chown #$run-directory (passwd:uid user) (passwd:gid user))
          (chmod #$run-directory #o755)))))

(define (papo-cronjobs _config)
  (list))

(define (papo-accounts config)
  (match-record config <papo-configuration>
      (user group)
    (list
     (user-group
       (name group)
       (system? #t))
     (user-account
       (name user)
       (group group)
       (system? #t)
       (comment "The user for runtime execution of papo code")
       (home-directory "/var/empty")
       (shell
         (file-append shadow "/sbin/nologin"))))))

(define (wrapped-command config)
  (match-record config <papo-configuration>
      (package data-directory
       run-in-container? container-name container-namespaces extra-mappings)
    (let ((bin (file-append package "/bin/papo")))
      (if (not run-in-container?)
        bin
        (least-authority-wrapper
         bin
         #:name       container-name
         #:namespaces container-namespaces
         #:directory  data-directory
         #:preserved-environment-variables
         '()
         #:mappings
         (append
          (list
           (file-system-mapping
             (source data-directory)
             (target source)
             (writable? #t))
           (file-system-mapping
             (source (file-append glibc-locales "/lib/locale"))
             (target "/run/current-system/locale")))
          extra-mappings))))))

(define (exec-action config . static-args)
  (match-record config <papo-configuration>
      (user group log-file data-directory)
    #~(lambda dynamic-args
        (fork+exec-command
         (append '(#$@static-args) dynamic-args)
         #:user      #$user
         #:group     #$group
         #:directory #$data-directory
         #:log-file  #$log-file))))

(define (papo-shepherd-services config)
  (let ((cmd (wrapped-command config)))
    (list
     (shepherd-service
       (provision '(papo))
       (requirement '())
       (start (exec-action config cmd "ircd"))
       (stop #~(make-kill-destructor SIGKILL))
       (documentation
         #"-
           The Shepherd service that runs the server via "papo-ircd"."#)))))

(define-public papo-service-type
  (service-type
    (name 'papo)
    (extensions
      (list
       (service-extension shepherd-root-service-type
                          papo-shepherd-services)
       (service-extension etc-service-type
                          papo-etc-files)
       (service-extension profile-service-type
                          (compose list papo-configuration-package))
       (service-extension activation-service-type
                          papo-activation)
       (service-extension account-service-type
                          papo-accounts)
       (service-extension mcron-service-type
                          papo-cronjobs)
       (service-extension rottlog-service-type
                          papo-log-rotations)))
    (default-value (papo-configuration))
    (description
      #"-
        The top-level system service for papo code.

        It includes:
        - the Shepherd service for starting, stopping and reloading the
          service ("papo");
        - a list of cronjobs to be added to the system for sending documents
          proactively;
        - activation script for setting up the initial directories and permissions;
        - the "papo" group and "papo" account for running the production service;
        - log management (storage and rotation) for logs produced by the running services.

        The defaults of <papo-configuration> provide sane values for all of these."#)))