feat: add the entire plugin

lua/fugitive-ts/parser.lua

@@ -0,0 +1,89 @@
+---@class fugitive-ts.Hunk
+---@field filename string
+---@field lang string
+---@field start_line integer
+---@field lines string[]
+
+local M = {}
+
+---@param filename string
+---@param custom_langs? table<string, string>
+---@return string?
+local function get_lang_from_filename(filename, custom_langs)
+  if custom_langs and custom_langs[filename] then
+    return custom_langs[filename]
+  end
+
+  local ft = vim.filetype.match({ filename = filename })
+  if not ft then
+    return nil
+  end
+
+  local lang = vim.treesitter.language.get_lang(ft)
+  if lang then
+    local ok = pcall(vim.treesitter.language.inspect, lang)
+    if ok then
+      return lang
+    end
+  end
+
+  return nil
+end
+
+---@param bufnr integer
+---@param custom_langs? table<string, string>
+---@return fugitive-ts.Hunk[]
+function M.parse_buffer(bufnr, custom_langs)
+  local lines = vim.api.nvim_buf_get_lines(bufnr, 0, -1, false)
+  ---@type fugitive-ts.Hunk[]
+  local hunks = {}
+
+  ---@type string?
+  local current_filename = nil
+  ---@type string?
+  local current_lang = nil
+  ---@type integer?
+  local hunk_start = nil
+  ---@type string[]
+  local hunk_lines = {}
+
+  local function flush_hunk()
+    if hunk_start and #hunk_lines > 0 and current_lang then
+      table.insert(hunks, {
+        filename = current_filename,
+        lang = current_lang,
+        start_line = hunk_start,
+        lines = hunk_lines,
+      })
+    end
+    hunk_start = nil
+    hunk_lines = {}
+  end
+
+  for i, line in ipairs(lines) do
+    local filename = line:match('^[MADRC%?!]%s+(.+)$')
+    if filename then
+      flush_hunk()
+      current_filename = filename
+      current_lang = get_lang_from_filename(filename, custom_langs)
+    elseif line:match('^@@.-@@') then
+      flush_hunk()
+      hunk_start = i
+    elseif hunk_start then
+      local prefix = line:sub(1, 1)
+      if prefix == ' ' or prefix == '+' or prefix == '-' then
+        table.insert(hunk_lines, line)
+      elseif line == '' or line:match('^[MADRC%?!]%s+') or line:match('^%a') then
+        flush_hunk()
+        current_filename = nil
+        current_lang = nil
+      end
+    end
+  end
+
+  flush_hunk()
+
+  return hunks
+end
+
+return M