local config = require('muwiki.config')

local M = {}

function M.open_in_buffer(filepath)
  vim.cmd.edit(vim.fn.fnameescape(filepath))
end

-- Lookup wiki path by name (e.g., "default" -> "~/wiki/")
function M.wiki_path(name)
  if not config.options.dirs or #config.options.dirs == 0 then
    vim.notify('MuWiki: No dirs configured. See :help muwiki-configuration', vim.log.levels.ERROR)
    return nil
  end

  if name then
    for _, dir in ipairs(config.options.dirs) do
      if dir.name == name then
        return dir.path
      end
    end
    vim.notify(string.format('Wiki "%s" not found, using default', name), vim.log.levels.WARN)
  end

  return config.options.dirs[1].path
end

-- Find which wiki contains this buffer's file (cached per-buffer)
function M.wiki_root(bufnr)
  bufnr = bufnr or 0

  if vim.b[bufnr].muwiki_root ~= nil then
    return vim.b[bufnr].muwiki_root or nil
  end

  local filepath = vim.api.nvim_buf_get_name(bufnr)
  local normalized = vim.fs.normalize(filepath)

  for _, dir in ipairs(config.options.dirs or {}) do
    if vim.startswith(normalized, dir.path) then
      vim.b[bufnr].muwiki_root = dir.path
      return dir.path
    end
  end

  vim.b[bufnr].muwiki_root = false
  return nil
end

function M.open_index(name)
  local wiki_path = M.wiki_path(name)
  if not wiki_path then
    return
  end

  local index_path = vim.fs.joinpath(wiki_path, config.options.index_file)
  M.open_in_buffer(index_path)
end

function M.resolve(filepath, wiki_root)
  local path = filepath:gsub('^file://', '')
  local path_type = path:sub(1, 1)
  if path_type == '.' then
    local current_dir = vim.fs.dirname(vim.api.nvim_buf_get_name(0))
    path = vim.fs.joinpath(current_dir, path)
  elseif path_type ~= '/' and path_type ~= '~' then
    local base = wiki_root or vim.fs.dirname(vim.api.nvim_buf_get_name(0))
    path = vim.fs.joinpath(base, path)
  end
  return vim.fs.normalize(path)
end

function M.normalize_filename(text)
  local normalized = text:lower()
  normalized = normalized:gsub('%s+', '_')
  normalized = normalized:gsub('[^%w_%-%.]', '')
  return normalized
end

return M