feat(opencode): fff search tools (#27802)

Co-authored-by: Shoubhit Dash <shoubhit2005@gmail.com>

packages/opencode/src/server/routes/instance/httpapi/handlers/file.ts

@@ -2,6 +2,7 @@ import * as InstanceState from "@/effect/instance-state"
 import { FileSystem } from "@opencode-ai/core/filesystem"
 import { LocationServiceMap } from "@opencode-ai/core/location-layer"
 import { Ripgrep } from "@opencode-ai/core/filesystem/ripgrep"
+import { Search } from "@opencode-ai/core/filesystem/search"
 import { FSUtil } from "@opencode-ai/core/fs-util"
 import { AbsolutePath, RelativePath } from "@opencode-ai/core/schema"
 import { Effect, Layer } from "effect"
@@ -12,6 +13,7 @@ import { InstanceHttpApi } from "../api"
 export const fileHandlers = HttpApiBuilder.group(InstanceHttpApi, "file", (handlers) =>
   Effect.gen(function* () {
     const ripgrep = yield* Ripgrep.Service
+    const search = yield* Search.Service
     const locations = yield* LocationServiceMap
 
     const filesystem = Effect.fnUntraced(function* <A, E, R>(effect: Effect.Effect<A, E, R>) {
@@ -29,11 +31,18 @@ export const fileHandlers = HttpApiBuilder.group(InstanceHttpApi, "file", (handl
     const findFile = Effect.fn("FileHttpApi.findFile")(function* (ctx: {
       query: { query: string; dirs?: "true" | "false"; type?: "file" | "directory"; limit?: number }
     }) {
+      const directory = (yield* InstanceState.context).directory
+      const limit = ctx.query.limit ?? 10
+      const kind = ctx.query.type ?? (ctx.query.dirs === "false" ? "file" : "all")
+      // Prefer fff (frecency + fuzzy ranking) and trust its ordering. Fall back
+      // to the ripgrep-backed FileSystem.find when fff is unavailable.
+      const fff = yield* search.file({ cwd: directory, query: ctx.query.query, limit, kind }).pipe(Effect.orDie)
+      if (fff !== undefined) return fff
       return (yield* filesystem(
         FileSystem.Service.use((fs) =>
           fs.find({
             query: ctx.query.query,
-            limit: ctx.query.limit ?? 10,
+            limit,
             type: ctx.query.type ?? (ctx.query.dirs === "false" ? "file" : undefined),
           }),
         ),
@@ -91,4 +100,4 @@ export const fileHandlers = HttpApiBuilder.group(InstanceHttpApi, "file", (handl
       .handle("content", content)
       .handle("status", status)
   }),
-).pipe(Layer.provide(LocationServiceMap.layer))
+).pipe(Layer.provide(LocationServiceMap.layer), Layer.provide(Search.defaultLayer))