/// <summary>
/// Checks out preconfirmed email table to see if a user has already opted in.
/// This way they wont have to opt-in twice if they resubscribe later.
/// It also prevents us from knowing too much about our users - we can't reverse this hash and we don't store unsubscribed emails.
/// </summary>
/// <param name="email"></param>
/// <returns></returns>
public async Task <bool> CheckIsPreconfirmed(string email)
{
await FirestoreSetup();
try {
string hashed = EncryptorService.OneWayHash(email.ToLowerInvariant());
hashed = EncryptorService.Base64Encode(hashed);
DocumentReference doc = DBHandle.Collection(PRECONFIRMED).Document(hashed);
DocumentSnapshot ds = await doc.GetSnapshotAsync();
return(ds.Exists);
} catch (Exception e) {
Logger.Log($"Some error ocurred while checking if the supplied email was preconfirmed: {e.Message}");
return(false);
}
}
/// <summary>
/// A user can request to be expunged from the system.
/// </summary>
/// <param name="email"></param>
/// <returns></returns>
public async Task GDPRDelete(string email)
{
await FirestoreSetup();
try {
string hashed = EncryptorService.OneWayHash(email.ToLowerInvariant());
hashed = EncryptorService.Base64Encode(hashed);
DocumentReference doc = DBHandle.Collection(PRECONFIRMED).Document(hashed);
await DBHandle.RunTransactionAsync(async transaction => {
transaction.Delete(doc);
});
}
catch (Exception e) {
Logger.Log($"Some error ocurred while deleteing a preconfirmed hash: {e.Message}");
}
}
public MailgunEmail MakeEmail(Subscriber s, List <LambdaMatch> lms)
{
// remember to include an Unsubscribe Link
int itemCount = lms.Sum(x => x.Posts.Count);
string subjectSingle = "1 new item that matched your criteria has been posted";
string subjectPlural = $"{itemCount} new items that matched your critiera have been posted";
MailgunEmail m = new MailgunEmail()
{
From = POSTMASTER,
To = { s.DocumentId },
Subject = itemCount == 1 ? subjectSingle : subjectPlural
};
string body = (itemCount == 1 ? subjectSingle : subjectPlural) + "\n\n";
string BSTtoSTring(BST bst)
{
switch (bst)
{
case BST.BST:
return("buy, sell, or trade");
case BST.BUY:
return("buy");
case BST.SELL:
return("sell");
case BST.TRADE:
return("trade");
case BST.NONE:
return("none");
}
return("");
}
foreach (LambdaMatch lm in lms)
{
// Assemble Subheader
string WTStr = $"People looking to {BSTtoSTring(lm.FbMatch.BST)}";
string fromStr = "products from " + (lm.FbMatch.Companies.Any() ? $"companies [{String.Join(", ", lm.FbMatch.Companies)}]" : "any company");
Currency c = CurrencyMap.CurrencyDict[lm.FbMatch.Currency];
string priceStr = lm.FbMatch.Price.HasValue ? $"for {(lm.FbMatch.BST == BST.BUY ? "more than or equal to " : "less than or equal to")} " + $"{c.symbol}{lm.FbMatch.Price.Value} {c.Code}" : "at any price";
string matchBody = $"{WTStr} {fromStr} {priceStr}:\n";
// Assemble Items
foreach (BSTComment comment in lm.Posts)
{
string seller = comment.Seller;
string comp = comment.Company;
string product = comment.Product == "?" ? "<product unknown>" : comment.Product;
string url = comment.Url;
Currency c2 = CurrencyMap.CurrencyDict[comment.Currency];
string pstr = comment.Price == 0 ? "<price not posted>" : $"{c2.symbol}{comment.Price} {c2.Code}";
string commentStr = $"{comp} {product} by {seller} for {pstr}\n{url}\n\n";
matchBody += commentStr;
}
body += matchBody;
}
// make unsubscribe link
string encryptionKey = Environment.GetEnvironmentVariable("ESK8BST_ENCRYPTION_KEY");
string encryptedPayload = EncryptorService.Base64Encode(s.DocumentId); //AESThenHMAC.SimpleEncryptWithPassword(s.DocumentId.ToLower(), encryptionKey);
string link = $"https://1lol87xzbj.execute-api.us-east-2.amazonaws.com/Prod/unsubscribe?confirmkey={encryptedPayload}";
string unsubtext = $"Unsubscribe: {link}";
body += $"\n\n\n\n {unsubtext}";
m.Body = body;
return(m);
}