From 2d75690773dbc4be8a29e4fcff24ba198ea2cc66 Mon Sep 17 00:00:00 2001
From: Alex Yatskov <alex@foosoft.net>
Date: Tue, 18 Oct 2022 20:46:21 -0700
Subject: [PATCH] Enable header cycling

---
 lua/hflip.lua | 63 ++++++++++++++++++++-------------------------------
 1 file changed, 25 insertions(+), 38 deletions(-)

diff --git a/lua/hflip.lua b/lua/hflip.lua
index dd77e87..5b9e8d1 100644
--- a/lua/hflip.lua
+++ b/lua/hflip.lua
@@ -6,48 +6,35 @@ local function file_exists(path)
     return vim.loop.fs_stat(path) ~= nil
 end
 
-local function locate_flip_path(name, exts)
-    for key, _ in pairs(exts) do
-        local path = name .. key
-        if file_exists(path) then
-            return path
-        end
+local function hflip()
+    local exts = {'.h', '.hpp', '.c', '.cpp', '.inl'}
+    for i = 1, #exts do
+        table.insert(exts, exts[i]:upper())
+    end
 
-        local path_upper = name .. key:upper()
-        if file_exists(path_upper) then
-            return path_upper
+    local path = vim.api.nvim_buf_get_name(vim.api.nvim_get_current_buf())
+    local name, ext = split_ext(path)
+    if not ext then
+        return
+    end
+
+    local ext_index = nil
+    for i, e in ipairs(exts) do
+        if e == ext:lower() then
+            ext_index = i
+            break
         end
     end
-end
+    if not ext_index then
+        return
+    end
 
-local function hflip()
-    local header_exts = {
-        ['.h'] = true,
-        ['.hpp'] = true,
-        ['.lua'] = true,
-    }
-
-    local source_exts = {
-        ['.c'] = true,
-        ['.cpp'] = true
-    }
-
-    local index = vim.api.nvim_get_current_buf()
-    local path = vim.api.nvim_buf_get_name(index)
-    local name, ext = split_ext(path)
-
-    if ext ~= nil then
-        local ext_lower = ext:lower()
-
-        local flip_path
-        if header_exts[ext_lower] then
-            flip_path = locate_flip_path(name, source_exts)
-        elseif source_exts[ext_lower] then
-            flip_path = locate_flip_path(name, header_exts)
-        end
-
-        if flip_path then
-            vim.cmd(string.format('e %s', flip_path))
+    for i = 1, #exts do
+        local j = (i + ext_index - 1) % #exts + 1
+        local next_path = name .. exts[j]
+        if file_exists(next_path) then
+            vim.cmd(string.format('e %s', next_path))
+            break
         end
     end
 end