local M = {} ---@class OpencodeSessionPatchLine ---@field old? integer ---@field new? integer ---@param patch string ---@return OpencodeSessionPatchLine[] function M.line_map(patch) local map = {} local old, new = 0, 0 local old_left, new_left = 0, 0 for row, line in ipairs(vim.split(patch:gsub('\r\n', '\n'), '\n', { plain = true, trimempty = true })) do local old_start, old_size, new_start, new_size = line:match('^@@ %-(%d+),?(%d*) %+(%d+),?(%d*) @@') map[row] = {} if old_start then old, new = tonumber(old_start) - 1, tonumber(new_start) - 1 old_left = old_size == '' and 1 or tonumber(old_size) new_left = new_size == '' and 1 or tonumber(new_size) elseif line:sub(1, 1) == ' ' and old_left > 0 and new_left > 0 then old, new = old + 1, new + 1 old_left, new_left = old_left - 1, new_left - 1 map[row] = { old = old, new = new } elseif line:sub(1, 1) == '-' and old_left > 0 then old, old_left = old + 1, old_left - 1 map[row] = { old = old } elseif line:sub(1, 1) == '+' and new_left > 0 then new, new_left = new + 1, new_left - 1 map[row] = { new = new } end end return map end ---Reconstruct both revisions from a full-context unified patch. ---@param patch string ---@return string[]?, string[]? function M.sides(patch) local before, after = {}, {} local old_pos, new_pos = 1, 1 ---@type number, number local old_count, new_count = 0, 0 local saw_hunk = false for _, line in ipairs(vim.split(patch:gsub('\r\n', '\n'), '\n', { plain = true })) do local old_start, old_size, new_start, new_size = line:match('^@@ %-(%d+),?(%d*) %+(%d+),?(%d*) @@') if old_start then if saw_hunk and (old_count ~= 0 or new_count ~= 0) then return nil, nil end local old_length = old_size == '' and 1 or assert(tonumber(old_size)) local new_length = new_size == '' and 1 or assert(tonumber(new_size)) if tonumber(old_start) ~= old_pos - (old_length == 0 and 1 or 0) or tonumber(new_start) ~= new_pos - (new_length == 0 and 1 or 0) then return nil, nil end old_count, new_count = old_length, new_length saw_hunk = true elseif saw_hunk and (old_count > 0 or new_count > 0) then local marker, text = line:sub(1, 1), line:sub(2) if marker == ' ' then before[#before + 1], after[#after + 1] = text, text old_count, new_count = old_count - 1, new_count - 1 old_pos, new_pos = old_pos + 1, new_pos + 1 elseif marker == '-' then before[#before + 1] = text old_count, old_pos = old_count - 1, old_pos + 1 elseif marker == '+' then after[#after + 1] = text new_count, new_pos = new_count - 1, new_pos + 1 else return nil, nil end if old_count < 0 or new_count < 0 then return nil, nil end end end if not saw_hunk or old_count ~= 0 or new_count ~= 0 then return nil, nil end return before, after end return M