local M = {}

local function setup_package_path()
  local plugin_path = debug.getinfo(1, "S").source:gsub("^@", ""):match("(.*/)") or ""
  plugin_path = plugin_path:gsub("/lua/scl_lsp", "")
  local lua_path = plugin_path .. "/lua"
  if not package.path:match(lua_path) then
    package.path = lua_path .. "/?.lua;" .. package.path
  end
end

function M.setup(opts)
  setup_package_path()
  opts = opts or {}

  local lspconfig_avail, lspconfig = pcall(require, "lspconfig")
  if not lspconfig_avail then
    vim.notify("lspconfig not found. Please install nvim-lspconfig.", vim.log.levels.ERROR)
    return
  end

  local server_path = opts.server_path or vim.fn.expand("~/dev/scl_lsp/src/main.lua")

  local root_patterns = { ".git", "data_types", "plc.data.json" }
  local function get_root_dir(fname)
    local root = vim.fs.root(fname, root_patterns)
    return root or vim.fn.fnamemodify(fname, ":h")
  end

  local function on_attach(client, bufnr)
    if opts.lsp and opts.lsp.on_attach then
      opts.lsp.on_attach(client, bufnr)
    end

    if opts.lsp.formatting then
      vim.api.nvim_buf_create_user_command(bufnr, "LspSCLFormat", function()
        vim.lsp.buf.format({ name = "scl-language-server" })
      end, {})
    end
  end

  lspconfig.scl_lsp = {
    default_config = {
      name = "scl-language-server",
      cmd = { "lua", server_path },
      filetypes = { "scl" },
      root_dir = get_root_dir,
      settings = {},
      on_attach = on_attach,
    },
    docs = {
      description = "Language server for Siemens SCL (LSP, Linter, Formatter)",
      default_config = {
        name = "scl-language-server",
        cmd = { "lua", server_path },
        filetypes = { "scl" },
        root_dir = "root_pattern('.git', 'data_types', 'plc.data.json')",
      },
    },
  }

  M.setup_syntax(opts)
  M.create_commands()

  if opts.auto_prefix ~= false then
    M.setup_auto_prefix()
  end
end

function M.setup_syntax(opts)
  local has_ts, ts = pcall(require, "nvim-treesitter.parsers")
  if has_ts and ts.get_parser_configs then
    local ok, parser_config = pcall(ts.get_parser_configs)
    if ok and parser_config then
      parser_config.scl = {
        install_info = {
          url = "file://" .. vim.fn.expand("~/dev/scl_lsp"),
          files = { "src/parser.c" },
          generate_requires_npm = false,
          requires_generate_from_grammar = false,
        },
        filetype = "scl",
      }
    end
  end

  if opts.cmp then
    local function try_register()
      local cmp_ok, cmp = pcall(require, "blink.cmp")
      local blink_source_ok, blink_source = pcall(require, "scl.blink_cmp_source")
      if cmp_ok and cmp and cmp.add_source_provider and blink_source_ok then
        local source_config = {
          name = "scl",
          provider = blink_source,
          score_offset = 100,
        }
        pcall(cmp.add_source_provider, "scl", source_config)
        pcall(cmp.add_filetype_source, "scl", "scl")

        vim.notify("SCL: blink.cmp source registered", vim.log.levels.INFO)
        return true
      end
      return false
    end

    if not try_register() then
      vim.api.nvim_create_autocmd("BufEnter", {
        pattern = "*.scl",
        once = true,
        callback = try_register,
      })
    end
  end

  if opts.workspace_types ~= false then
    local ok, workspace_types = pcall(require, "scl.workspace_types")
    if ok then
      workspace_types.setup({
        project_root = opts.project_root,
        library_paths = opts.library_paths,
        debug = opts.debug,
      })
    end
  end
end

function M.setup_auto_prefix()
  local ok, auto_prefix = pcall(require, "scl.auto_prefix")
  if ok then
    auto_prefix.setup()
  end
end

function M.prefix_current_word()
  local ok, auto_prefix = pcall(require, "scl.auto_prefix")
  if ok then
    auto_prefix.prefix_word()
  end
end

function M.show_variables()
  local ok, variables = pcall(require, "scl.variables")
  if not ok then
    vim.notify("SCL variables module not found", vim.log.levels.WARN)
    return
  end

  local vars = variables.extract_variables()
  if #vars == 0 then
    vim.notify("No local variables found", vim.log.levels.INFO)
    return
  end

  local lines = { "Local Variables:", "---" }
  for _, var in ipairs(vars) do
    local type_info = var.type and (" : " .. var.type) or ""
    table.insert(lines, "#" .. var.name .. type_info)
  end
  vim.notify(table.concat(lines, "\n"), vim.log.levels.INFO)
end

function M.show_workspace_types()
  local ok_ws, ws = pcall(require, "scl.workspace_types")
  local ok_udt, udt = pcall(require, "scl.udt_parser")
  local ok_fb, fb = pcall(require, "scl.fb_parser")

  if not ok_ws or not ok_udt or not ok_fb then
    vim.notify("SCL workspace modules not found", vim.log.levels.WARN)
    return
  end

  local root = ws.get_project_root()
  local udt_names = udt.get_all_udt_names()
  local fb_names = fb.get_all_fb_names()

  if not root then
    vim.notify("No project root detected", vim.log.levels.WARN)
    return
  end

  vim.notify("Project: " .. root .. "\nUDTs: " .. #udt_names .. "\nFBs/Functions: " .. #fb_names, vim.log.levels.INFO)
end

function M.rescan_workspace_types()
  local ok_ws, ws = pcall(require, "scl.workspace_types")
  local ok_udt, udt = pcall(require, "scl.udt_parser")
  local ok_fb, fb = pcall(require, "scl.fb_parser")

  if not ok_ws or not ok_udt or not ok_fb then
    vim.notify("SCL workspace modules not found", vim.log.levels.WARN)
    return
  end

  udt.clear_cache()
  fb.clear_cache()
  ws.clear_root_cache()

  local udt_result = ws.scan_project_udts()
  local fb_result = ws.scan_project_fbs()

  vim.notify("Scanned UDTs: " .. udt_result.parsed_count .. "/" .. udt_result.total_files ..
            ", FBs: " .. fb_result.parsed_count .. "/" .. fb_result.total_files, vim.log.levels.INFO)
end

function M.create_commands()
  vim.api.nvim_create_user_command("SCLShowVariables", function() M.show_variables() end, {})
  vim.api.nvim_create_user_command("SCLShowWorkspaceTypes", function() M.show_workspace_types() end, {})
  vim.api.nvim_create_user_command("SCLRescanWorkspaceTypes", function() M.rescan_workspace_types() end, {})
  vim.api.nvim_create_user_command("SCLPrefixWord", function() M.prefix_current_word() end, {})
end

return M