chore: import upstream snapshot with attribution

src/utils/detect-tools.ts

@@ -0,0 +1,109 @@
+import os from "os"
+import path from "path"
+import { pathExists } from "./files"
+import { resolveOpenCodeGlobalRoot } from "./opencode-config"
+import { resolveCodexHome } from "./resolve-home"
+
+export type DetectedTool = {
+  name: string
+  detected: boolean
+  reason: string
+}
+
+type DetectableTool = {
+  name: string
+  detectPaths: (home: string, cwd: string, options: DetectPathOptions) => string[]
+}
+
+type DetectPathOptions = {
+  useCodexHomeEnv: boolean
+}
+
+const detectableTools: DetectableTool[] = [
+  {
+    name: "opencode",
+    detectPaths: (home, cwd) => {
+      // Resolve the OpenCode global root through the shared helper so that
+      // detection agrees with install/cleanup on `OPENCODE_CONFIG_DIR`. When
+      // the env var is unset, the helper falls back to `os.homedir()`, which
+      // may differ from the `home` arg threaded through for testability; in
+      // that case prefer the explicit `home` param so existing callers that
+      // override it keep working.
+      const envDir = process.env.OPENCODE_CONFIG_DIR?.trim()
+      const globalRoot = envDir
+        ? resolveOpenCodeGlobalRoot()
+        : path.join(home, ".config", "opencode")
+      return [globalRoot, path.join(cwd, ".opencode")]
+    },
+  },
+  {
+    name: "codex",
+    detectPaths: (home, _cwd, options) => {
+      if (!options.useCodexHomeEnv) return [path.join(home, ".codex")]
+      const codexHome = resolveCodexHome(undefined)
+      const defaultCodexHome = path.join(home, ".codex")
+      return codexHome === defaultCodexHome ? [defaultCodexHome] : [codexHome, defaultCodexHome]
+    },
+  },
+  {
+    name: "pi",
+    detectPaths: (home) => [path.join(home, ".pi")],
+  },
+  {
+    name: "droid",
+    detectPaths: (home) => [path.join(home, ".factory")],
+  },
+  {
+    name: "copilot",
+    detectPaths: (home, cwd) => [
+      path.join(home, ".copilot"),
+      path.join(cwd, ".github", "skills"),
+      path.join(cwd, ".github", "agents"),
+      path.join(cwd, ".github", "copilot-instructions.md"),
+    ],
+  },
+  {
+    name: "antigravity",
+    detectPaths: (home, cwd) => [
+      path.join(cwd, ".agy"),
+      path.join(home, ".gemini", "antigravity-cli"),
+    ],
+  },
+  {
+    name: "qwen",
+    detectPaths: (home, cwd) => [
+      path.join(home, ".qwen"),
+      path.join(cwd, ".qwen"),
+    ],
+  },
+]
+
+export async function detectInstalledTools(
+  home?: string,
+  cwd: string = process.cwd(),
+): Promise<DetectedTool[]> {
+  const effectiveHome = home ?? os.homedir()
+  const options = { useCodexHomeEnv: home === undefined }
+  const results: DetectedTool[] = []
+  for (const target of detectableTools) {
+    let detected = false
+    let reason = "not found"
+    for (const p of target.detectPaths(effectiveHome, cwd, options)) {
+      if (await pathExists(p)) {
+        detected = true
+        reason = `found ${p}`
+        break
+      }
+    }
+    results.push({ name: target.name, detected, reason })
+  }
+  return results
+}
+
+export async function getDetectedTargetNames(
+  home?: string,
+  cwd: string = process.cwd(),
+): Promise<string[]> {
+  const tools = await detectInstalledTools(home, cwd)
+  return tools.filter((t) => t.detected).map((t) => t.name)
+}