namespace PrivaPub.Api.Mastodon.Auth
{
	public static class MastodonScopes
	{
		public static readonly string[] All =
		{
			"read", "write", "follow", "push", "profile",
			"read:accounts", "read:blocks", "read:bookmarks", "read:favourites", "read:filters", "read:follows", "read:lists",
			"read:mutes", "read:notifications", "read:search", "read:statuses",
			"write:accounts", "write:blocks", "write:bookmarks", "write:conversations", "write:favourites", "write:filters",
			"write:follows", "write:lists", "write:media", "write:mutes", "write:notifications", "write:reports", "write:statuses"
		};

		public static IReadOnlyList<string> Parse(string scopes)
		{
			var parsed = (scopes ?? string.Empty).Split(new[] { ' ', '+', ',' }, StringSplitOptions.RemoveEmptyEntries)
				.Where(s => All.Contains(s))
				.Distinct()
				.ToList();
			return parsed.Count == 0 ? new[] { "read" } : parsed;
		}

		public static bool Grants(IEnumerable<string> granted, string required)
		{
			var scopes = granted as ICollection<string> ?? granted.ToList();
			if (scopes.Contains(required))
				return true;
			var colon = required.IndexOf(':');
			if (colon > 0 && scopes.Contains(required[..colon]))
				return true;
			return required.StartsWith("read:follows") || required.StartsWith("write:follows") || required.StartsWith("write:blocks")
				|| required.StartsWith("read:blocks") || required.StartsWith("write:mutes") || required.StartsWith("read:mutes")
				? scopes.Contains("follow")
				: false;
		}
	}
}