local tags = {}
-- support -add-tags, --add-options, -remove-tags, -remove-options, clear-tags, clear-options
-- for struct and line range
-- gomodifytags -file demo.go -struct Server -add-tags json
-- gomodifytags -file demo.go -struct Server -add-tags json -w
-- gomodifytags -file demo.go -struct Server -add-tags json,xml
-- gomodifytags -file demo.go -struct Server -add-tags json,xml -transform camelcase
-- gomodifytags -file demo.go -line 8,11 -clear-tags xml

local opts = {"-add-tags", "-add-options", "-remove-tags", "-remove-options", "-clear-tags", "-clear-options"}
local gomodify = "gomodifytags"
local transform = vim.g.go_nvim_tag_transfer
tags.modify = function(...)
  require("go.install").install(gomodify)
  local fname = vim.fn.expand("%") -- %:p:h ? %:p
  local row, col = unpack(vim.api.nvim_win_get_cursor(0))
  row, col = row + 1, col + 1
  local ns = require("go.ts.go").get_struct_node_at_pos(row, col)
  if ns == nil or ns == {} then
    return
  end

  -- print("parnode" .. vim.inspect(ns))
  local struct_name = ns.name
  local rs, re = ns.dim.s.r, ns.dim.e.r
  setup = {gomodify, "-format", "json", "-file", fname, "-struct", struct_name, '-w'}
  if transform ~= nil then
    table.insert(setup.args, "-transform")
    table.insert(setup.args, transform)
  end
  local arg = {...}
  for i, v in ipairs(arg) do
    table.insert(setup, v)
  end

  if #arg == 1 and arg[1] ~= "clear-tags" then
    table.insert(setup, "json")
  end
  -- print(vim.inspect(setup))
  local j =
    vim.fn.jobstart(
    setup,
    {
      on_stdout = function(jobid, data, event)
        if not data or #data == 1 and data[1] == "" then
          return
        end
        local tagged = vim.fn.json_decode(data)
        -- print(vim.inspect(tagged))
        -- print(tagged["start"], tagged["end"], tagged.lines)
        if tagged.errors ~= nil or tagged.lines == nil or tagged["start"] == nil or tagged["start"]  == 0 then
          print("failed to set tags" .. vim.inspect(tagged))
        end
        vim.api.nvim_buf_set_lines(0, tagged["start"]-1, tagged["start"]-1+#tagged.lines, false, tagged.lines)
        vim.cmd("write")
        print("wrote " .. tostring(tagged.lines))
      end
    }
  )
end

tags.add = function(...)
  local cmd = {"-add-tags"}
  local arg = {...}
  for _, v in ipairs(arg) do
    table.insert(cmd, v)
  end

  tags.modify(unpack(cmd))
end

tags.rm = function(...)
  local cmd = {"-remove-tags"}
  local arg = {...}
  for _, v in ipairs(arg) do
    table.insert(cmd, v)
  end
  tags.modify(unpack(cmd))
end

tags.clear = function()
  local cmd = {"-clear-tags"}
  tags.modify(unpack(cmd))
end

return tags