From ceb7f1bf53185dfb8b3bb0680f0de781c35f6528 Mon Sep 17 00:00:00 2001
From: Guillaume Hivert <hivert.is.coming@gmail.com>
Date: Fri, 2 Aug 2024 01:21:48 +0200
Subject: [PATCH] feat: add fuzzy search

---
 .../src/backend/gleam/type_search/state.gleam | 29 ++++++++++++++++++-
 .../src/backend/postgres/queries.gleam        |  1 -
 apps/backend/src/backend/router.gleam         |  1 -
 3 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/apps/backend/src/backend/gleam/type_search/state.gleam b/apps/backend/src/backend/gleam/type_search/state.gleam
index 3782597..9930818 100644
--- a/apps/backend/src/backend/gleam/type_search/state.gleam
+++ b/apps/backend/src/backend/gleam/type_search/state.gleam
@@ -42,7 +42,7 @@ fn loop(msg: msg.Msg, state: State) -> actor.Next(msg.Msg, State) {
       signature
       |> parse.parse_function
       |> result.nil_error
-      |> result.then(type_search.find(state.search, _, state.db))
+      |> result.then(permutation_search(state, _))
       |> option.from_result
       |> function.tap(fn(res) { process.send(subject, res) })
       actor.continue(state)
@@ -59,6 +59,33 @@ fn loop(msg: msg.Msg, state: State) -> actor.Next(msg.Msg, State) {
   actor.continue(state)
 }
 
+fn is_permutable(list: List(a), len: Int) {
+  case list {
+    _ if len > 4 -> False
+    [_, ..rest] -> is_permutable(rest, len + 1)
+    [] -> True
+  }
+}
+
+fn permutation_search(state: State, kind: parse.Kind) {
+  case kind {
+    parse.Function(params, return) -> {
+      let permutable = is_permutable(params, 0)
+      use <- bool.lazy_guard(when: !permutable, return: fn() {
+        type_search.find(state.search, kind, state.db)
+      })
+      Ok({
+        let permutations = list.permutations(params)
+        use permutation <- list.flat_map(permutations)
+        parse.Function(permutation, return)
+        |> type_search.find(state.search, _, state.db)
+        |> result.unwrap([])
+      })
+    }
+    _ -> Error(Nil)
+  }
+}
+
 fn compute_rows(
   offset: Int,
   db: pgo.Connection,
diff --git a/apps/backend/src/backend/postgres/queries.gleam b/apps/backend/src/backend/postgres/queries.gleam
index ce56914..a5825f4 100644
--- a/apps/backend/src/backend/postgres/queries.gleam
+++ b/apps/backend/src/backend/postgres/queries.gleam
@@ -458,7 +458,6 @@ pub fn find_similar_type_names(db: pgo.Connection, name: String) {
   |> pgo.execute(db, [pgo.text(name)], dynamic.element(0, dynamic.string))
   |> result.map_error(error.DatabaseError)
   |> result.map(fn(r) { r.rows })
-  |> io.debug
 }
 
 pub fn name_search(db: pgo.Connection, query: String) {
diff --git a/apps/backend/src/backend/router.gleam b/apps/backend/src/backend/router.gleam
index 8b5b608..36dfaeb 100644
--- a/apps/backend/src/backend/router.gleam
+++ b/apps/backend/src/backend/router.gleam
@@ -8,7 +8,6 @@ import cors_builder as cors
 import gleam/erlang/process
 import gleam/http
 import gleam/int
-import gleam/io
 import gleam/json
 import gleam/list
 import gleam/option