(defpackage :access-log-reader
   (:shadowing-import-from :multi-fun :rest)
   (:shadowing-import-from :data-lens :pick :defun-ct)
   (:use :cl :multi-fun :data-lens :alexandria :fw.lu)
   (:export ))
 (in-package :access-log-reader)
 
 (defun make-timestamp (record)
   (let ((local-time:*default-timezone* local-time:+utc-zone+))
     (destructuring-bind (day month year time) record
       (local-time:with-decoded-timestamp (:hour hour :minute minute :sec second :nsec nsec) time
         (local-time:encode-timestamp nsec second minute hour day month year)))))
 
 (defun extract-query-params (s)
   (serapeum:mapply 'cons
                    (map 'list 
                         (serapeum:op (coerce (fwoar.string-utils:split #\= _ :count 2) 'list))
                         (fwoar.string-utils:split #\& s))))
 (defparameter +access-log-parser+
   (list (delimited-field #\:)
         (delimited-field #\space) 
         (as (delimited-field #\space) (lambda (s) (subseq s 1 (1- (length s)))))
         (as (delimited-field #\space) (lambda (s) (unless (equal s "-") (parse-integer s))))
         (as (delimited-field #\space) (lambda (s) (unless (equal s "-") (parse-integer s))))
         (as (delimited-field #\space) #'parse-integer)
         (as (delimited-field #\space) (lambda (s) (unless (equal s "-") (parse-integer s))))
         (as (subformat (v (ignore-char #\[)
                           (as (delimited-field #\/) #'parse-integer)
                           (as (delimited-field #\/) (serapeum:op (position _ local-time:+short-month-names+ :test 'equal)))
                           (as (delimited-field #\:) #'parse-integer)
                           (as (delimited-field #\]) (lambda (x) (local-time:parse-timestring (remove #\space x) :allow-missing-date-part t)))))
             'make-timestamp)
         (whitespace)
         (as (delimited-field #\space) (lambda (s) (subseq s 1)))
         (splat-result (as (delimited-field #\space)
                           (alexandria:compose
                            (data-lens:juxt 'quri:uri-path
                                            (alexandria:compose 'extract-query-params 'quri:uri-query))
                            'quri:uri)))
         (delimited-field #\")
         (delimited-field #\space)
         (delimited-field #\space)
         (delimited-field #\space)
         (ignore-char #\")
         (as (delimited-field #\") 'quri:uri)
         (whitespace)
         (rest)))
 
 (defun parse-log (f)
   (parse-file +access-log-parser+ f))