From 06443cd1dda60ea4398580721a3da115561ff20d Mon Sep 17 00:00:00 2001
From: Justin Kramer <jkkramer@gmail.com>
Date: Fri, 13 Jul 2012 08:50:20 -0400
Subject: [PATCH] api

---
 src/honeysql/core.clj | 150 +++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 149 insertions(+), 1 deletion(-)

diff --git a/src/honeysql/core.clj b/src/honeysql/core.clj
index 834f5cd..8e8ee38 100644
--- a/src/honeysql/core.clj
+++ b/src/honeysql/core.clj
@@ -1 +1,149 @@
-(ns honeysql.core)
+(ns honeysql.core
+  (:refer-clojure :exclude [group-by])
+  (:require [honeysql.format :as format]))
+
+(def format-sql format/format-sql)
+
+(defn select [& fields]
+  (let [[m fields] (if (map? (first fields))
+                     [(first fields) (rest fields)]
+                     [{} fields])]
+    (assoc m :select fields)))
+
+(defn merge-select [sql-map & fields]
+  (update-in sql-map [:select] concat fields))
+
+(defn from [& tables]
+  (let [[m tables] (if (map? (first tables))
+                     [(first tables) (rest tables)]
+                     [{} tables])]
+    (assoc m :from tables)))
+
+(defn merge-from [sql-map & tables]
+  (update-in sql-map [:from] concat tables))
+
+(defn where [& preds]
+  (let [[m preds] (if (map? (first preds))
+                    [(first preds) (rest preds)]
+                    [{} preds])]
+    (assoc m :where (if (= 1 (count preds))
+                      (first preds)
+                      (vec (cons :and preds))))))
+
+(defn merge-where [sql-map & preds]
+  (if (empty? preds)
+    sql-map
+    (let [[merge-op preds] (if (keyword? (first preds))
+                             [(first preds) (rest preds)]
+                             [:and preds])]
+      (assoc sql-map :where (if (contains? sql-map :where)
+                              (vec (concat [merge-op (:where sql-map)] preds))
+                              (vec (if (= 1 (count preds))
+                                     (first preds)
+                                     (cons merge-op preds))))))))
+
+(defn join [& clauses]
+  (let [[m clauses] (if (map? (first clauses))
+                      [(first clauses) (rest clauses)]
+                      [{} clauses])
+        clauses (if (not (coll? (first clauses)))
+                  [clauses]
+                  clauses)]
+    (assoc m :join clauses)))
+
+(defn merge-join [sql-map & clauses]
+  (let [clauses (if (not (coll? (first clauses)))
+                  [clauses]
+                  clauses)]
+    (update-in sql-map [:join] concat clauses)))
+
+(defn group-by [& fields]
+  (let [[m fields] (if (map? (first fields))
+                     [(first fields) (rest fields)]
+                     [{} fields])]
+    (assoc m :group-by fields)))
+
+(defn merge-group-by [sql-map & fields]
+  (update-in sql-map [:group-by] concat fields))
+
+(defn having [& preds]
+  (let [[m preds] (if (map? (first preds))
+                    [(first preds) (rest preds)]
+                    [{} preds])]
+    (assoc m :having (if (= 1 (count preds))
+                       (first preds)
+                       (vec (cons :and preds))))))
+
+(defn merge-having [sql-map & preds]
+  (if (empty? preds)
+    sql-map
+    (let [[merge-op preds] (if (keyword? (first preds))
+                             [(first preds) (rest preds)]
+                             [:and preds])]
+      (assoc sql-map :having (if (contains? sql-map :having)
+                               (vec (concat [merge-op (:having sql-map)] preds))
+                               (vec (if (= 1 (count preds))
+                                      (first preds)
+                                      (cons merge-op preds))))))))
+
+(defn order-by [& fields]
+  (let [[m fields] (if (map? (first fields))
+                     [(first fields) (rest fields)]
+                     [{} fields])]
+    (assoc m :order-by fields)))
+
+(defn merge-order-by [sql-map & fields]
+  (update-in sql-map [:order-by] concat fields))
+
+(defn limit
+  ([l]
+     (limit {} l))
+  ([sql-map l]
+     (assoc sql-map :limit l)))
+
+(defn offset
+  ([o]
+     (offset {} o))
+  ([sql-map o]
+     (assoc sql-map :offset o)))
+
+(def ^:private handlers
+  {:select select
+   :from from
+   :where where
+   :join join
+   :group-by group-by
+   :having having
+   :order-by order-by
+   :limit limit
+   :offset offset})
+
+(def ^:private merge-handlers
+  {:select merge-select
+   :from merge-from
+   :where merge-where
+   :join merge-join
+   :group-by merge-group-by
+   :having merge-having
+   :order-by merge-order-by
+   :limit limit
+   :offset offset})
+
+(defn- build-sql [handlers clauses]
+  (let [[base clauses] (if (map? (first clauses))
+                         [(first clauses) (rest clauses)]
+                         [{} clauses])]
+    (reduce
+     (fn [sql-map [op args]]
+       (let [handler (handlers op)]
+         (if (or (#{:where :having} op) (not (coll? args)))
+           (handler sql-map args)
+           (apply handler sql-map args))))
+     base
+     (partition 2 clauses))))
+
+(defn sql [& clauses]
+  (build-sql handlers clauses))
+
+(defn merge-sql [& clauses]
+  (build-sql merge-handlers clauses))