(ns db-populate
  (:import java.lang.Math)
  (:require [clojure.contrib.generic.collection :as gc])
  (:use clojure.contrib.sql
        clojure.contrib.probabilities.finite-distributions
        clojure.contrib.probabilities.monte-carlo
        clojure.contrib.probabilities.random-numbers
        utils))

(def *num-users* 500)
(def *mean-posts-per-user* 200)
(def *std-dev-posts-per-user* 1.5)
(def *image-msg-frequency* 0.5)
(def *nick-prefix* "user")
(def *sample-message-sentences*
     ["Aim at new love victories",
      "Bomb her womb from your huge battleship",
      "Face your new mate without fear",
      "Get armed for a new love battle",
      "Upgrade your weapon used to make love"])

(defn sample-unit []
  (first (gc/seq rand-stream)))

(defn sample-lognormal [mean sigma]
  (first (gc/seq (random-stream (lognormal (Math/log mean) sigma)
                                rand-stream))))

(defn rand-elt [coll]
  (nth coll (rand-int (count coll))))

(defn nick-func [i]
  (str *nick-prefix* "-" i "-" (System/currentTimeMillis)))

(defn hash-func [i]
  (str "HASH"))

(defn email-func [i]
  (str *nick-prefix* "-" i "@" i ".com"))

(defn make-user [label]
  (println "Creating user" label)
  (let [qry (str "INSERT INTO users (nick, hash, email) "
                 "VALUES (?, ?, ?) RETURNING user_id")
        nick  (nick-func label)
        hash  (hash-func label)
        email (email-func label)
        res   (do-select [qry nick hash email])]
    ((first res) :user_id)))

(defn sample-text-msg []
  (rand-elt *sample-message-sentences*))

(defn sample-image-msg []
  "http://localhost:8080/images/20100310/1268271054246-abc-b7413897775a39087737d54768adca55d3c97cf4.jpeg")

(defn sample-msg-contents []
  (if (<= *image-msg-frequency* (sample-unit))
    [(sample-image-msg) true]
    [(sample-text-msg) false]))

(defn sample-room-id []
  1)

(defn make-messages [user-id]
  (let [num-msgs (int (sample-lognormal *mean-posts-per-user* 
                                        *std-dev-posts-per-user*))]
    (println "Creating" num-msgs "messages for userid" user-id)
    (doseq [i (range num-msgs)]
      (let [[content is-image] (sample-msg-contents)
            room-id            (sample-room-id)
            qry                (str "INSERT INTO messages "
                                    "(user_id, room_id, content, is_image) "
                                    "VALUES (?, ?, ?, ?) RETURNING message_id")]
        (do-select [qry user-id room-id content is-image])))))
        
(defn populate [n-str]
  (let [n (Integer/parseInt n-str)]
    (doall (map (comp make-messages make-user) (range n)))))

(defn clear []
  (println "Clearing all users starting with" *nick-prefix*)
  (let [params ["nick LIKE ?" (str *nick-prefix* "%")]
        cnt (first (do-delete "users" params))]
    (println "Cleared" cnt "users")))
    
(def *command-map* {"populate" populate "clear" clear})

(defn parse-command-args
  ([] (prn "Usage: db_populate.clj command num"))
  ([cmd-str & more]
     (if-let [cmd (*command-map* cmd-str)]
       (apply cmd more)
       (println "Unknown command '" cmd-str "'"))))

(apply parse-command-args (rest *command-line-args*))