local M = {}

local function lsp_highlight_document(client)
  if lvim.lsp.document_highlight == false then
    return -- we don't need further
  end
  -- Set autocommands conditional on server_capabilities
  if client.resolved_capabilities.document_highlight then
    vim.api.nvim_exec(
      [[
      hi LspReferenceRead cterm=bold ctermbg=red guibg=#464646
      hi LspReferenceText cterm=bold ctermbg=red guibg=#464646
      hi LspReferenceWrite cterm=bold ctermbg=red guibg=#464646
      augroup lsp_document_highlight
        autocmd! * <buffer>
        autocmd CursorHold <buffer> lua vim.lsp.buf.document_highlight()
        autocmd CursorMoved <buffer> lua vim.lsp.buf.clear_references()
      augroup END
    ]],
      false
    )
  end
end

function M.lsp_highlight_document(client)
  lsp_highlight_document(client)
end

-- Taken from https://www.reddit.com/r/neovim/comments/gyb077/nvimlsp_peek_defination_javascript_ttserver/
function M.preview_location(location, context, before_context)
  -- location may be LocationLink or Location (more useful for the former)
  context = context or 15
  before_context = before_context or 0
  local uri = location.targetUri or location.uri
  if uri == nil then
    return
  end
  local bufnr = vim.uri_to_bufnr(uri)
  if not vim.api.nvim_buf_is_loaded(bufnr) then
    vim.fn.bufload(bufnr)
  end

  local range = location.targetRange or location.range
  local contents = vim.api.nvim_buf_get_lines(
    bufnr,
    range.start.line - before_context,
    range["end"].line + 1 + context,
    false
  )
  local filetype = vim.api.nvim_buf_get_option(bufnr, "filetype")
  return vim.lsp.util.open_floating_preview(contents, filetype, { border = lvim.lsp.popup_border })
end

function M.preview_location_callback(_, method, result)
  local context = 15
  if result == nil or vim.tbl_isempty(result) then
    print("No location found: " .. method)
    return nil
  end
  if vim.tbl_islist(result) then
    M.floating_buf, M.floating_win = M.preview_location(result[1], context)
  else
    M.floating_buf, M.floating_win = M.preview_location(result, context)
  end
end

function M.PeekDefinition()
  if vim.tbl_contains(vim.api.nvim_list_wins(), M.floating_win) then
    vim.api.nvim_set_current_win(M.floating_win)
  else
    local params = vim.lsp.util.make_position_params()
    return vim.lsp.buf_request(0, "textDocument/definition", params, M.preview_location_callback)
  end
end

function M.PeekTypeDefinition()
  if vim.tbl_contains(vim.api.nvim_list_wins(), M.floating_win) then
    vim.api.nvim_set_current_win(M.floating_win)
  else
    local params = vim.lsp.util.make_position_params()
    return vim.lsp.buf_request(0, "textDocument/typeDefinition", params, M.preview_location_callback)
  end
end

function M.PeekImplementation()
  if vim.tbl_contains(vim.api.nvim_list_wins(), M.floating_win) then
    vim.api.nvim_set_current_win(M.floating_win)
  else
    local params = vim.lsp.util.make_position_params()
    return vim.lsp.buf_request(0, "textDocument/implementation", params, M.preview_location_callback)
  end
end

function M.common_on_attach(client, bufnr)
  if lvim.lsp.on_attach_callback then
    lvim.lsp.on_attach_callback(client, bufnr)
  end
  lsp_highlight_document(client)
end

function M.common_capabilities()
  local capabilities = vim.lsp.protocol.make_client_capabilities()
  capabilities.textDocument.completion.completionItem.snippetSupport = true
  capabilities.textDocument.completion.completionItem.resolveSupport = {
    properties = {
      "documentation",
      "detail",
      "additionalTextEdits",
    },
  }
  return capabilities
end

return M