using System;
using System.Text.RegularExpressions;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using Discord;
using Discord.WebSocket;
using Newtonsoft.Json;
using QRCoder;
namespace vassago.Conversion
{
public static class Converter
{
private delegate decimal Convert1Way(decimal input);
private static string currencyPath;
private static ExchangePairs currencyConf = null;
private static DateTime lastUpdatedCurrency = DateTime.UnixEpoch;
private static List<Tuple<string, string, Convert1Way, Convert1Way>> knownConversions = new List<Tuple<string, string, Convert1Way, Convert1Way>>();
private static Dictionary<List<string>, string> knownAliases = new Dictionary<List<string>, string>(new List<KeyValuePair<List<string>, string>>());
public static string DebugInfo()
{
var convertibles = knownConversions.Select(kc => kc.Item1).Union(knownConversions.Select(kc => kc.Item2)).Union(
knownAliases.Keys.SelectMany(k => k)).Distinct();
return $"{convertibles.Count()} convertibles; {string.Join(", ", convertibles)}";
}
public static void Load(string currencyPath)
{
Converter.currencyPath = currencyPath;
loadStatic();
Task.Run(async () =>
{
while (true)
{
await Task.Delay(TimeSpan.FromHours(8));
loadCurrency();
}
});
}
private static void loadStatic()
{
knownConversions = new List<Tuple<string, string, Convert1Way, Convert1Way>>();
knownAliases = new Dictionary<List<string>, string>(new List<KeyValuePair<List<string>, string>>());
var convConf = JsonConvert.DeserializeObject<ConversionConfig>(File.ReadAllText("assets/conversion.json").ToLower());
foreach (var unit in convConf.Units)
{
knownAliases.Add(unit.Aliases.ToList(), unit.Canonical);
}
foreach (var lp in convConf.LinearPairs)
{
AddLinearPair(lp.item1, lp.item2, lp.factor);
}
loadCurrency();
}
private static void loadCurrency()
{
Console.WriteLine("loading currency exchange data.");
if (currencyConf != null)
{
knownConversions.RemoveAll(kc => kc.Item1 == currencyConf.Base);
}
if (File.Exists(currencyPath))
{
currencyConf = JsonConvert.DeserializeObject<ExchangePairs>(File.ReadAllText(currencyPath).ToLower());
if (!knownAliases.ContainsValue(currencyConf.Base))
{
knownAliases.Add(new List<string>() { }, currencyConf.Base);
}
foreach (var rate in currencyConf.rates)
{
if (!knownAliases.ContainsValue(rate.Key))
{
knownAliases.Add(new List<string>() { rate.Key.ToLower() }, rate.Key);
}
AddLinearPair(currencyConf.Base, rate.Key, rate.Value);
}
}
}
public static string Convert(decimal numericTerm, string sourceunit, string destinationUnit)
{
//normalize units
var normalizationAttemptSource = NormalizeUnit(sourceunit.ToLower());
if (normalizationAttemptSource?.Count() == 0)
{
return $"can't find {sourceunit}";
}
var normalizedSourceUnit = normalizationAttemptSource.First();
var normalizationAttemptDest = NormalizeUnit(destinationUnit.ToLower());
if (normalizationAttemptDest?.Count() == 0)
{
return $"can't find {destinationUnit}";
}
var normalizedDestUnit = normalizationAttemptDest.First();
if (normalizedSourceUnit == normalizedDestUnit)
{
return $"source and dest are the same, so... {numericTerm} {normalizedDestUnit}?";
}
var foundPath = exhaustiveBreadthFirst(normalizedDestUnit, new List<string>() { normalizedSourceUnit })?.ToList();
//resolve ambiguity
var disambiguationPaths = new List<List<string>>();
if (normalizationAttemptSource.Count() > 1 && normalizationAttemptDest.Count() > 1)
{
foreach (var possibleSourceUnit in normalizationAttemptSource)
{
foreach (var possibleDestUnit in normalizationAttemptDest)
{
foundPath = exhaustiveBreadthFirst(possibleDestUnit, new List<string>() { possibleSourceUnit })?.ToList();
if (foundPath != null)
{
disambiguationPaths.Add(foundPath.ToList());
normalizedSourceUnit = possibleSourceUnit;
normalizedDestUnit = possibleDestUnit;
}
}
}
}
else if (normalizationAttemptSource.Count() > 1)
{
foreach (var possibleSourceUnit in normalizationAttemptSource)
{
foundPath = exhaustiveBreadthFirst(normalizedDestUnit, new List<string>() { possibleSourceUnit })?.ToList();
if (foundPath != null)
{
disambiguationPaths.Add(foundPath.ToList());
normalizedSourceUnit = possibleSourceUnit;
}
}
}
else if (normalizationAttemptDest.Count() > 1)
{
foreach (var possibleDestUnit in normalizationAttemptDest)
{
foundPath = exhaustiveBreadthFirst(possibleDestUnit, new List<string>() { normalizedSourceUnit })?.ToList();
if (foundPath != null)
{
disambiguationPaths.Add(foundPath.ToList());
normalizedDestUnit = possibleDestUnit;
}
}
}
if (disambiguationPaths.Count() > 1)
{
var sb = new StringBuilder();
sb.Append("unresolvable ambiguity.");
foreach(var possibility in disambiguationPaths)
{
sb.Append($" {possibility.First()} -> {possibility.Last()}?");
}
return sb.ToString();
}
if (disambiguationPaths.Count() == 1)
{
//TODO: I'm not entirely sure this is necessary.
foundPath = disambiguationPaths.First();
}
//actually do the math.
if (foundPath != null)
{
var accumulator = numericTerm;
for (int j = 0; j < foundPath.Count() - 1; j++)
{
var forwardConversion = knownConversions.FirstOrDefault(kc => kc.Item1 == foundPath[j] && kc.Item2 == foundPath[j + 1]);
if (forwardConversion != null)
{
accumulator = forwardConversion.Item3(accumulator);
}
else
{
var reverseConversion = knownConversions.First(kc => kc.Item2 == foundPath[j] && kc.Item1 == foundPath[j + 1]);
accumulator = reverseConversion.Item4(accumulator);
}
}
if (currencyConf != null && (normalizedDestUnit == currencyConf.Base || currencyConf.rates.Select(r => r.Key).Contains(normalizedDestUnit)))
{
return $"{String.Format("approximately {0:0.00}", accumulator)} {normalizedDestUnit} as of {currencyConf.DateUpdated.ToLongDateString()}";
}
else
{
if (String.Format("{0:G3}", accumulator).Contains("E-"))
{
return $"{accumulator} {normalizedDestUnit}";
}
else
{
return $"{String.Format("{0:N}", accumulator)} {normalizedDestUnit}";
}
}
}
return "dimensional analysis failure - I know those units but can't find a path between them.";
}
private static List<string> NormalizeUnit(string unit)
{
if (string.IsNullOrWhiteSpace(unit))
return new();
var normalizedUnit = unit;
//first, if it does exist in conversions, that's the canonical name.
if (knownConversions.FirstOrDefault(c => c.Item1 == normalizedUnit || c.Item2 == normalizedUnit) != null)
{
return new List<string>() { normalizedUnit };
}
//if "unit" isn't a canonical name... actually it never should be; a conversion should use it.
if (!knownAliases.ContainsValue(normalizedUnit))
{
//then we look through aliases...
var keys = knownAliases.Keys.Where(listkey => listkey.Contains(normalizedUnit));
if (keys?.Count() > 1)
{
var toReturn = new List<string>();
foreach (var key in keys)
{
toReturn.Add(knownAliases[key]);
}
return toReturn;
}
else if (keys.Count() == 1)
{
//for the canonical name.
return new List<string>() { knownAliases[keys.First()] };
}
}
if (normalizedUnit.EndsWith("es"))
{
return NormalizeUnit(normalizedUnit.Substring(0, normalizedUnit.Length - 2));
}
else if (normalizedUnit.EndsWith('s'))
{
return NormalizeUnit(normalizedUnit.Substring(0, normalizedUnit.Length - 1));
}
return new();
}
private static IEnumerable<string> exhaustiveBreadthFirst(string dest, IEnumerable<string> currentPath)
{
var last = currentPath.Last();
if (last == dest)
{
return currentPath;
}
var toTest = new List<List<string>>();
foreach (var conv in knownConversions)
{
if (conv.Item1 == last && currentPath.Contains(conv.Item2) == false && conv.Item3 != null)
{
var test = exhaustiveBreadthFirst(dest, currentPath.Append(conv.Item2));
if (test != null)
return test;
}
if (conv.Item2 == last && currentPath.Contains(conv.Item1) == false && conv.Item4 != null)
{
var test = exhaustiveBreadthFirst(dest, currentPath.Append(conv.Item1));
if (test != null)
return test;
}
}
return null;
}
private static void AddLinearPair(string key1, string key2, decimal factor)
{
var reverseFactor = 1.0m / factor;
knownConversions.Add(new Tuple<string, string, Convert1Way, Convert1Way>(
key1, key2, x => x * factor, y => y * reverseFactor
));
}
}
}