using System.Text.Encodings.Web;
using System.Text.Json;
using System.Text.Json.Nodes;
using System.Text.RegularExpressions;

var root = FindRoot();
var folder = Path.Combine(root, "src", "MeWeb.App", "Strings");
var options = new JsonSerializerOptions { WriteIndented = true, Encoder = JavaScriptEncoder.UnsafeRelaxedJsonEscaping };
var placeholder = new Regex(@"\{\d+\}");

if (args.Length >= 1 && args[0] == "check") return Check();
if (args.Length == 3 && args[0] == "set") return Set(args[1], args[2]);
Console.Error.WriteLine("usage: dotnet run tools/strings.cs -- check | set <Key> <values.json>   (values.json maps a language code to its text)");
return 2;

int Check()
{
  var english = Read("en");
  var problems = 0;
  foreach (var file in Directory.GetFiles(folder, "*.json").OrderBy(f => f, StringComparer.Ordinal))
  {
    var code = Path.GetFileNameWithoutExtension(file);
    if (code == "en") continue;
    var values = Read(code);
    var missing = english.Keys.Where(k => !values.ContainsKey(k)).ToList();
    var extra = values.Keys.Where(k => !english.ContainsKey(k)).ToList();
    var mismatched = english.Keys.Where(values.ContainsKey)
      .Where(k => !placeholder.Matches(english[k]).Select(m => m.Value).Order().SequenceEqual(placeholder.Matches(values[k]).Select(m => m.Value).Order())).ToList();
    if (missing.Count + extra.Count + mismatched.Count == 0) continue;
    problems++;
    Console.WriteLine($"{code}: missing [{string.Join(", ", missing)}] extra [{string.Join(", ", extra)}] placeholders [{string.Join(", ", mismatched)}]");
  }
  Console.WriteLine(problems == 0 ? $"strings: OK ({english.Count} keys)" : $"strings: {problems} language(s) to fix");
  return problems == 0 ? 0 : 1;
}

int Set(string key, string valuesPath)
{
  var values = JsonNode.Parse(File.ReadAllText(valuesPath)).AsObject();
  if (values["en"] is null) throw new InvalidOperationException("values.json must carry at least \"en\"");
  foreach (var (code, value) in values)
  {
    var strings = Read(code);
    strings[key] = (string)value;
    Write(code, strings);
  }
  Console.WriteLine($"{key}: set in {values.Count} language(s)");
  return 0;
}

SortedDictionary<string, string> Read(string code)
{
  var path = Path.Combine(folder, $"{code}.json");
  if (!File.Exists(path)) return new SortedDictionary<string, string>(StringComparer.Ordinal);
  var node = JsonNode.Parse(File.ReadAllText(path)).AsObject();
  return new SortedDictionary<string, string>(node.ToDictionary(p => p.Key, p => (string)p.Value), StringComparer.Ordinal);
}

void Write(string code, SortedDictionary<string, string> strings)
{
  var node = new JsonObject();
  foreach (var (key, value) in strings) node[key] = value;
  File.WriteAllText(Path.Combine(folder, $"{code}.json"), node.ToJsonString(options) + "\n");
}

static string FindRoot()
{
  var dir = new DirectoryInfo(Directory.GetCurrentDirectory());
  while (dir is not null && !File.Exists(Path.Combine(dir.FullName, "MeWeb.slnx"))) dir = dir.Parent;
  return dir?.FullName ?? throw new InvalidOperationException("run from inside the repository (MeWeb.slnx not found)");
}