---@brief
---
--- https://github.com/typescript-language-server/typescript-language-server
---
--- `ts_ls`, aka `typescript-language-server`, is a Language Server Protocol implementation for TypeScript wrapping `tsserver`. Note that `ts_ls` is not `tsserver`.
---
--- `typescript-language-server` depends on `typescript`. Both packages can be installed via `npm`:
--- ```sh
--- npm install -g typescript typescript-language-server
--- ```
---
--- To configure typescript language server, add a
--- [`tsconfig.json`](https://www.typescriptlang.org/docs/handbook/tsconfig-json.html) or
--- [`jsconfig.json`](https://code.visualstudio.com/docs/languages/jsconfig) to the root of your
--- project.
---
--- Here's an example that disables type checking in JavaScript files.
---
--- ```json
--- {
---   "compilerOptions": {
---     "module": "commonjs",
---     "target": "es6",
---     "checkJs": false
---   },
---   "exclude": [
---     "node_modules"
---   ]
--- }
--- ```
---
--- Use the `:LspTypescriptSourceAction` command to see "whole file" ("source") code-actions such as:
--- - organize imports
--- - remove unused code
---
--- Use the `:LspTypescriptGoToSourceDefinition` command to navigate to the source definition of a symbol (e.g., jump to the original implementation instead of type definitions).
---
--- ### Monorepo support
---
--- `ts_ls` supports monorepos by default. It will automatically find the `tsconfig.json` or `jsconfig.json` corresponding to the package you are working on.
--- This works without the need of spawning multiple instances of `ts_ls`, saving memory.
---
--- It is recommended to use the same version of TypeScript in all packages, and therefore have it available in your workspace root. The location of the TypeScript binary will be determined automatically, but only once.
---
--- Some care must be taken here to correctly infer whether a file is part of a Deno program, or a TS program that
--- expects to run in Node or Web Browsers. This supports having a Deno module using the denols LSP as a part of a
--- mostly-not-Deno monorepo. We do this by finding the nearest package manager lock file, and the nearest deno.json
--- or deno.jsonc.
---
--- Example:
---
--- ```
--- project-root
--- +-- node_modules/...
--- +-- package-lock.json
--- +-- package.json
--- +-- packages
---     +-- deno-module
---     |   +-- deno.json
---     |   +-- package.json <-- It's normal for Deno projects to have package.json files!
---     |   +-- src
---     |       +-- index.ts <-- this is a Deno file
---     +-- node-module
---         +-- package.json
---         +-- src
---             +-- index.ts <-- a non-Deno file (ie, should use ts_ls or tsgols)
--- ```
---
--- From the file being edited, we walk up to find the nearest package manager lockfile. This is PROJECT ROOT.
--- From the file being edited, find the nearest deno.json or deno.jsonc. This is DENO ROOT.
--- From the file being edited, find the nearest deno.lock. This is DENO LOCK ROOT
--- If DENO LOCK ROOT is found, and PROJECT ROOT is missing or shorter, then this is a deno file, and we abort.
--- If DENO ROOT is found, and it's longer than or equal to PROJECT ROOT, then this is a Deno file, and we abort.
--- Otherwise, attach at PROJECT ROOT, or the cwd if not found.

---@type vim.lsp.Config
return {
  init_options = { hostInfo = 'neovim' },
  cmd = function(dispatchers, config)
    local cmd = 'typescript-language-server'
    if (config or {}).root_dir then
      local local_cmd = vim.fs.joinpath(config.root_dir, 'node_modules/.bin', cmd)
      if vim.fn.executable(local_cmd) == 1 then
        cmd = local_cmd
      end
    end
    return vim.lsp.rpc.start({ cmd, '--stdio' }, dispatchers)
  end,
  filetypes = {
    'javascript',
    'javascriptreact',
    'typescript',
    'typescriptreact',
  },
  root_dir = function(bufnr, on_dir)
    -- The project root is where the LSP can be started from
    -- As stated in the documentation above, this LSP supports monorepos and simple projects.
    -- We select then from the project root, which is identified by the presence of a package
    -- manager lock file.
    local root_markers = { 'package-lock.json', 'yarn.lock', 'pnpm-lock.yaml', 'bun.lockb', 'bun.lock' }
    -- Give the root markers equal priority by wrapping them in a table
    root_markers = vim.fn.has('nvim-0.11.3') == 1 and { root_markers, { '.git' } }
      or vim.list_extend(root_markers, { '.git' })
    -- exclude deno
    local deno_root = vim.fs.root(bufnr, { 'deno.json', 'deno.jsonc' })
    local deno_lock_root = vim.fs.root(bufnr, { 'deno.lock' })
    local project_root = vim.fs.root(bufnr, root_markers)
    if deno_lock_root and (not project_root or #deno_lock_root > #project_root) then
      -- deno lock is closer than package manager lock, abort
      return
    end
    if deno_root and (not project_root or #deno_root >= #project_root) then
      -- deno config is closer than or equal to package manager lock, abort
      return
    end
    -- project is standard TS, not deno
    -- We fallback to the current working directory if no project root is found
    on_dir(project_root or vim.fn.getcwd())
  end,
  handlers = {
    -- handle rename request for certain code actions like extracting functions / types
    ['_typescript.rename'] = function(_, result, ctx)
      local client = assert(vim.lsp.get_client_by_id(ctx.client_id))
      vim.lsp.util.show_document({
        uri = result.textDocument.uri,
        range = {
          start = result.position,
          ['end'] = result.position,
        },
      }, client.offset_encoding)
      vim.lsp.buf.rename()
      return vim.NIL
    end,
  },
  commands = {
    ['editor.action.showReferences'] = function(command, ctx)
      local client = assert(vim.lsp.get_client_by_id(ctx.client_id))
      local file_uri, position, references = unpack(command.arguments)

      local quickfix_items = vim.lsp.util.locations_to_items(references --[[@as any]], client.offset_encoding)
      vim.fn.setqflist({}, ' ', {
        title = command.title,
        items = quickfix_items,
        context = {
          command = command,
          bufnr = ctx.bufnr,
        },
      })

      vim.lsp.util.show_document({
        uri = file_uri --[[@as string]],
        range = {
          start = position --[[@as lsp.Position]],
          ['end'] = position --[[@as lsp.Position]],
        },
      }, client.offset_encoding)
      ---@diagnostic enable: assign-type-mismatch

      vim.cmd('botright copen')
    end,
  },
  on_attach = function(client, bufnr)
    -- ts_ls provides `source.*` code actions that apply to the whole file. These only appear in
    -- `vim.lsp.buf.code_action()` if specified in `context.only`.
    vim.api.nvim_buf_create_user_command(bufnr, 'LspTypescriptSourceAction', function()
      local source_actions = vim.tbl_filter(function(action)
        return vim.startswith(action, 'source.')
      end, client.server_capabilities.codeActionProvider.codeActionKinds)

      vim.lsp.buf.code_action({
        context = {
          only = source_actions,
          diagnostics = {},
        },
      })
    end, {})

    -- Go to source definition command
    vim.api.nvim_buf_create_user_command(bufnr, 'LspTypescriptGoToSourceDefinition', function()
      local win = vim.api.nvim_get_current_win()
      local params = vim.lsp.util.make_position_params(win, client.offset_encoding)
      client:exec_cmd({
        command = '_typescript.goToSourceDefinition',
        title = 'Go to source definition',
        arguments = { params.textDocument.uri, params.position },
      }, { bufnr = bufnr }, function(err, result)
        if err then
          vim.notify('Go to source definition failed: ' .. err.message, vim.log.levels.ERROR)
          return
        end
        if not result or vim.tbl_isempty(result) then
          vim.notify('No source definition found', vim.log.levels.INFO)
          return
        end
        vim.lsp.util.show_document(result[1], client.offset_encoding, { focus = true })
      end)
    end, { desc = 'Go to source definition' })
  end,
}
