local util = require 'lspconfig.util'
local log = require 'vim.lsp.log'

return {
  default_config = {
    -- (default: false) Whether or not we should automatically start the
    -- Relay Compiler in watch mode when you open a project
    auto_start_compiler = false,

    -- (default: nil) Path to a relay config relative to the `root_dir`.
    -- Without this, the compiler will search for your config. This is
    -- helpful if your relay project is in a nested directory.
    path_to_config = nil,

    cmd = { 'relay-compiler', 'lsp' },
    filetypes = {
      'javascript',
      'javascriptreact',
      'javascript.jsx',
      'typescript',
      'typescriptreact',
      'typescript.tsx',
    },
    root_dir = util.root_pattern('relay.config.*', 'package.json'),
    on_new_config = function(config, root_dir)
      local project_root = util.find_node_modules_ancestor(root_dir)
      local node_bin_path = util.path.join(project_root, 'node_modules', '.bin')
      local compiler_cmd = { util.path.join(node_bin_path, 'relay-compiler'), '--watch' }
      local path = node_bin_path .. util.path.path_separator .. vim.env.PATH
      if config.cmd_env then
        config.cmd_env.PATH = path
      else
        config.cmd_env = { PATH = path }
      end

      if config.path_to_config then
        config.path_to_config = util.path.sanitize(config.path_to_config)
        local path_to_config = util.path.join(root_dir, config.path_to_config)
        if util.path.exists(path_to_config) then
          vim.list_extend(config.cmd, { config.path_to_config })
          vim.list_extend(compiler_cmd, { config.path_to_config })
        else
          log.error "[Relay LSP] Can't find Relay config file. Fallback to the default location..."
        end
      end
      if config.auto_start_compiler then
        vim.fn.jobstart(compiler_cmd, {
          on_exit = function()
            log.info '[Relay LSP] Relay Compiler exited'
          end,
          cwd = project_root,
        })
      end
    end,
    handlers = {
      ['window/showStatus'] = function(_, result)
        if not result then
          return {}
        end
        local log_message = string.format('[Relay LSP] %q', result.message)
        if result.type == 1 then
          log.error(log_message)
        end
        if result.type == 2 then
          log.warn(log_message)
        end
        if result.type == 3 then
          log.info(log_message)
        end
        return {}
      end,
    },
  },
  docs = {
    description = [[
    https://github.com/facebook/relay
    `Relay` is a JavaScript framework for building data-driven React applications

    Setup:

    - Make sure you have a Relay config file somewhere in your project.
    - We support standard config file formats (`.yml`, `.js`, `.json`), and the the `relay` field in your `package.json`
    - Make sure you have the `relay-compiler` installed in your project. The bare minimum is v13.
    - Make sure you are able to run the `relay-compiler` command from the command line. If `yarn relay-compiler` works, it's very likely that the LSP will work.
    - Remove / disable any conflicting GraphQL LSPs you have installed.

    Relay LSP is a part of the Relay Compiler binary and available when adding `relay-compiler` to your project's devDependencies.

    ```lua
    require'lspconfig'.relay_lsp.setup {
      -- (default: false) Whether or not we should automatically start
      -- the Relay Compiler in watch mode when you open a project
      auto_start_compiler = false,


      -- (default: null) Path to a relay config relative to the
      -- `root_dir`. Without this, the compiler will search for your
      -- config. This is helpful if your relay project is in a nested
      -- directory.
      path_to_config = nil,
    }
    ```
    ]],
    default_config = {
      root_dir = [[root_pattern("relay.config.*", "package.json")]],
      auto_start_compiler = false,
      path_to_config = nil,
    },
  },
}