path: root/runtime/lua/vim/diagnostic.lua

local M = {}

M.severity = {
  ERROR = 1,
  WARN = 2,
  INFO = 3,
  HINT = 4,
}

vim.tbl_add_reverse_lookup(M.severity)

local global_diagnostic_options = {
  signs = true,
  underline = true,
  virtual_text = true,
  update_in_insert = false,
  severity_sort = false,
}

-- Local functions {{{

---@private
local function to_severity(severity)
  return type(severity) == 'string' and M.severity[string.upper(severity)] or severity
end

---@private
local function filter_by_severity(severity, diagnostics)
  if not severity then
    return diagnostics
  end

  if type(severity) ~= "table" then
    severity = to_severity(severity)
    return vim.tbl_filter(function(t) return t.severity == severity end, diagnostics)
  end

  local min_severity = to_severity(severity.min) or M.severity.HINT
  local max_severity = to_severity(severity.max) or M.severity.ERROR

  return vim.tbl_filter(function(t) return t.severity <= min_severity and t.severity >= max_severity end, diagnostics)
end

---@private
local function resolve_optional_value(option, namespace, bufnr)
  local enabled_val = {}

  if not option then
    return false
  elseif option == true then
    return enabled_val
  elseif type(option) == 'function' then
    local val = option(namespace, bufnr)
    if val == true then
      return enabled_val
    else
      return val
    end
  elseif type(option) == 'table' then
    return option
  else
    error("Unexpected option type: " .. vim.inspect(option))
  end
end

local all_namespaces = {}

---@private
local function get_namespace(ns)
  if not all_namespaces[ns] then
    local name
    for k, v in pairs(vim.api.nvim_get_namespaces()) do
      if ns == v then
        name = k
        break
      end
    end

    if not name then
      return vim.notify("namespace does not exist or is anonymous", vim.log.levels.ERROR)
    end

    all_namespaces[ns] = {
      name = name,
      sign_group = string.format("vim.diagnostic.%s", name),
      opts = {}
    }
  end
  return all_namespaces[ns]
end

---@private
local function get_resolved_options(opts, namespace, bufnr)
  local ns = get_namespace(namespace)
  local resolved = vim.tbl_extend('keep', opts or {}, ns.opts, global_diagnostic_options)
  for k in pairs(global_diagnostic_options) do
    if resolved[k] ~= nil then
      resolved[k] = resolve_optional_value(resolved[k], namespace, bufnr)
    end
  end
  return resolved
end

-- Default diagnostic highlights
local diagnostic_severities = {
  [M.severity.ERROR] = { ctermfg = 1, guifg = "Red" };
  [M.severity.WARN] = { ctermfg = 3, guifg = "Orange" };
  [M.severity.INFO] = { ctermfg = 4, guifg = "LightBlue" };
  [M.severity.HINT] = { ctermfg = 7, guifg = "LightGrey" };
}

-- Make a map from DiagnosticSeverity -> Highlight Name
---@private
local function make_highlight_map(base_name)
  local result = {}
  for k in pairs(diagnostic_severities) do
    local name = M.severity[k]
    name = name:sub(1, 1) .. name:sub(2):lower()
    result[k] = "Diagnostic" .. base_name .. name
  end

  return result
end

local virtual_text_highlight_map = make_highlight_map("VirtualText")
local underline_highlight_map = make_highlight_map("Underline")
local floating_highlight_map = make_highlight_map("Floating")
local sign_highlight_map = make_highlight_map("Sign")

---@private
local define_default_signs = (function()
  local signs_defined = false
  return function()
    if signs_defined then
      return
    end

    for severity, sign_hl_name in pairs(sign_highlight_map) do
      if vim.tbl_isempty(vim.fn.sign_getdefined(sign_hl_name)) then
        local severity_name = M.severity[severity]
        vim.fn.sign_define(sign_hl_name, {
          text = (severity_name or 'U'):sub(1, 1),
          texthl = sign_hl_name,
          linehl = '',
          numhl = '',
        })
      end
    end

    signs_defined = true
  end
end)()

---@private
local function get_bufnr(bufnr)
  if not bufnr or bufnr == 0 then
    return vim.api.nvim_get_current_buf()
  end
  return bufnr
end

-- Metatable that automatically creates an empty table when assigning to a missing key
local bufnr_and_namespace_cacher_mt = {
  __index = function(t, bufnr)
    if not bufnr or bufnr == 0 then
      bufnr = vim.api.nvim_get_current_buf()
    end

    if rawget(t, bufnr) == nil then
      rawset(t, bufnr, {})
    end

    return rawget(t, bufnr)
  end,

  __newindex = function(t, bufnr, v)
    if not bufnr or bufnr == 0 then
      bufnr = vim.api.nvim_get_current_buf()
    end

    rawset(t, bufnr, v)
  end,
}

local diagnostic_cleanup = setmetatable({}, bufnr_and_namespace_cacher_mt)
local diagnostic_cache = setmetatable({}, bufnr_and_namespace_cacher_mt)
local diagnostic_cache_extmarks = setmetatable({}, bufnr_and_namespace_cacher_mt)
local diagnostic_attached_buffers = {}