feat: refactor file structure

lua/cp/diff.lua

@@ -1,189 +0,0 @@
----@class DiffResult
----@field content string[]
----@field highlights table[]?
----@field raw_diff string?
-
----@class DiffBackend
----@field name string
----@field render fun(expected: string, actual: string): DiffResult
-
-local M = {}
-
----@type DiffBackend
-local vim_backend = {
-  name = 'vim',
-  render = function(_, actual)
-    local actual_lines = vim.split(actual, '\n', { plain = true, trimempty = true })
-
-    return {
-      content = actual_lines,
-      highlights = nil,
-    }
-  end,
-}
-
----@type DiffBackend
-local git_backend = {
-  name = 'git',
-  render = function(expected, actual)
-    local tmp_expected = vim.fn.tempname()
-    local tmp_actual = vim.fn.tempname()
-
-    vim.fn.writefile(vim.split(expected, '\n', { plain = true }), tmp_expected)
-    vim.fn.writefile(vim.split(actual, '\n', { plain = true }), tmp_actual)
-
-    local cmd = {
-      'git',
-      'diff',
-      '--no-index',
-      '--word-diff=plain',
-      '--word-diff-regex=.',
-      '--no-prefix',
-      tmp_expected,
-      tmp_actual,
-    }
-
-    local result = vim.system(cmd, { text = true }):wait()
-
-    vim.fn.delete(tmp_expected)
-    vim.fn.delete(tmp_actual)
-
-    if result.code == 0 then
-      return {
-        content = vim.split(actual, '\n', { plain = true, trimempty = true }),
-        highlights = {},
-      }
-    else
-      local diff_content = result.stdout or ''
-      local lines = {}
-      local highlights = {}
-      local line_num = 0
-
-      for line in diff_content:gmatch('[^\n]*') do
-        if
-          line:match('^[%s%+%-]')
-          or (not line:match('^[@%-+]') and not line:match('^index') and not line:match('^diff'))
-        then
-          local clean_line = line
-          if line:match('^[%+%-]') then
-            clean_line = line:sub(2)
-          end
-
-          local col_pos = 0
-          local processed_line = ''
-          local i = 1
-
-          while i <= #clean_line do
-            local removed_start, removed_end = clean_line:find('%[%-[^%-]*%-]', i)
-            local added_start, added_end = clean_line:find('{%+[^%+]*%+}', i)
-
-            local next_marker_start = nil
-            local marker_type = nil
-
-            if removed_start and (not added_start or removed_start < added_start) then
-              next_marker_start = removed_start
-              marker_type = 'removed'
-            elseif added_start then
-              next_marker_start = added_start
-              marker_type = 'added'
-            end
-
-            if next_marker_start then
-              if next_marker_start > i then
-                local before_text = clean_line:sub(i, next_marker_start - 1)
-                processed_line = processed_line .. before_text
-                col_pos = col_pos + #before_text
-              end
-
-              local marker_end = (marker_type == 'removed') and removed_end or added_end
-              local marker_text = clean_line:sub(next_marker_start, marker_end)
-              local content_text
-
-              if marker_type == 'removed' then
-                content_text = marker_text:sub(3, -3)
-                table.insert(highlights, {
-                  line = line_num,
-                  col_start = col_pos,
-                  col_end = col_pos + #content_text,
-                  highlight_group = 'DiffDelete',
-                })
-              else
-                content_text = marker_text:sub(3, -3)
-                table.insert(highlights, {
-                  line = line_num,
-                  col_start = col_pos,
-                  col_end = col_pos + #content_text,
-                  highlight_group = 'DiffAdd',
-                })
-              end
-
-              processed_line = processed_line .. content_text
-              col_pos = col_pos + #content_text
-              i = marker_end + 1
-            else
-              local rest = clean_line:sub(i)
-              processed_line = processed_line .. rest
-              break
-            end
-          end
-
-          table.insert(lines, processed_line)
-          line_num = line_num + 1
-        end
-      end
-
-      return {
-        content = lines,
-        highlights = highlights,
-        raw_diff = diff_content,
-      }
-    end
-  end,
-}
-
----@type table<string, DiffBackend>
-local backends = {
-  vim = vim_backend,
-  git = git_backend,
-}
-
----@return string[]
-function M.get_available_backends()
-  return vim.tbl_keys(backends)
-end
-
----@param name string
----@return DiffBackend?
-function M.get_backend(name)
-  return backends[name]
-end
-
----@return boolean
-function M.is_git_available()
-  local result = vim.system({ 'git', '--version' }, { text = true }):wait()
-  return result.code == 0
-end
-
----@param preferred_backend? string
----@return DiffBackend
-function M.get_best_backend(preferred_backend)
-  if preferred_backend and backends[preferred_backend] then
-    if preferred_backend == 'git' and not M.is_git_available() then
-      return backends.vim
-    end
-    return backends[preferred_backend]
-  end
-
-  return backends.vim
-end
-
----@param expected string
----@param actual string
----@param backend_name? string
----@return DiffResult
-function M.render_diff(expected, actual, backend_name)
-  local backend = M.get_best_backend(backend_name)
-  return backend.render(expected, actual)
-end
-
-return M