local M = {}

function M.set_lines(bufnr, startindex, endindex, replacement)

if startindex < 0 then

startindex = #vim.buffer(bufnr) + 1 + startindex

end

if endindex < 0 then

endindex = #vim.buffer(bufnr) + 1 + endindex

end

if #replacement == endindex - startindex then

for i = startindex, endindex - 1, 1

do

vim.buffer(bufnr)[i + 1] = replacement[i - startindex]

end

else

if endindex < #vim.buffer(bufnr) then

for i = endindex + 1, #vim.buffer(bufnr), 1

do

replacement:add(vim.buffer(bufnr)[i])

end

end

for i = startindex, #replacement + startindex - 1, 1

do

if i + 1 > #vim.buffer(bufnr) then

vim.buffer(bufnr):insert(replacement[i - startindex])

else

vim.buffer(bufnr)[i + 1] = replacement[i - startindex]

end

end

for i = #replacement + startindex + 1, #vim.buffer(bufnr), 1

do

vim.buffer(bufnr)[#replacement + startindex + 1] = nil

end

end

end

return M