using System;
using System.Collections.Generic;
using System.Text.Json.Serialization;

namespace Emails.Transactional.Client
{
    /// <summary>
    /// A transactional email request to send an email 
    /// template.
    /// </summary>
    public class EmailTransactionRequest
    {
        /// <summary>
        /// The transactional send endpoint address
        /// </summary>
        [JsonIgnore]
        public Uri Endpoint { get; init; }
        /// <summary>
        /// A dictionary of email addresses/names of 
        /// users to send this email to
        /// </summary>
        [JsonPropertyName("to")]
        public Dictionary<string, string> ToAddresses { get; set; }
        /// <summary>
        /// A dictionary of email addresses/names of 
        /// users to carbon copy this email to
        /// </summary>
        [JsonPropertyName("cc")]
        public Dictionary<string, string> CcAddresses { get; set; }
        /// <summary>
        /// A dictionary of email addresses/names of 
        /// users to blind carbon copy this email to
        /// </summary>
        [JsonPropertyName("bcc")]
        public Dictionary<string, string> BccAddresses { get; set; }
        /// <summary>
        /// A dictionary of variables to substitute into the liquid 
        /// email template
        /// </summary>
        [JsonPropertyName("variables")]
        public Dictionary<string, string> Variables { get; set; }
        
        /// <summary>
        /// The subject of the email to send
        /// </summary>
        [JsonPropertyName("subject")]
        public string Subject { get; set; }
        
        /// <summary>
        /// The unique id of the email template to send 
        /// </summary>
        [JsonPropertyName("template_id")]
        public string TemplateId { get; set; }
        /// <summary>
        /// The system from email name. NOTE: This is a protected value
        /// </summary>
        [JsonPropertyName("from_name")]
        public string FromName { get; set; }
        /// <summary>
        /// The system from email address. NOTE: This is a protected value
        /// </summary>
        [JsonPropertyName("from_address")]
        public string FromAddress { get; set; }

        /// <summary>
        /// Creates a new email transaction with the specified email template to send
        /// </summary>
        /// <param name="templateId">The id of the template to send</param>
        /// <exception cref="ArgumentNullException"></exception>
        public EmailTransactionRequest(string templateId)
        {
            this.TemplateId = templateId ?? throw new ArgumentNullException(nameof(templateId));
        }
        /// <summary>
        /// Creates a new email transaction with the specified email template 
        /// and a single recipient
        /// </summary>
        /// <param name="templateId">The id of the template to send</param>
        /// <param name="toAddress">A singular recipient name</param>
        /// <param name="toName">A singlular recipient email address</param>
        /// <exception cref="ArgumentNullException"></exception>
        public EmailTransactionRequest(string templateId, string toName, string toAddress)
        {
            this.TemplateId = templateId ?? throw new ArgumentNullException(nameof(templateId));
            AddToAddress(toName, toAddress);
        }
        /// <summary>
        /// Adds a recipient to the To email address dictionary
        /// </summary>
        /// <param name="toName">The name of the user to send the email to</param>
        /// <param name="toAddress">The unique email address of the user to add to the recipient collection</param>
        public void AddToAddress(string toName, string toAddress)
        {
            ToAddresses ??= new(1);
            ToAddresses.Add(toAddress, toName);
        }
        /// <summary>
        /// Adds a recipient to the To email address dictionary
        /// </summary>
        /// <param name="toAddress">The unique email address of the user to add to the recipient collection</param>
        public void AddToAddress(string toAddress)
        {
            string name = toAddress.Split('@')[0];
            AddToAddress(name, toAddress);
        }
        /// <summary>
        /// Adds a carbon copy recipient to the current cc dictionary
        /// </summary>
        /// <param name="ccName">The name of the recipient</param>
        /// <param name="ccAddress">The unique email address of the bcc recipient</param>
        public void AddCcAddress(string ccName, string ccAddress)
        {
            CcAddresses ??= new(1);
            CcAddresses.Add(ccAddress, ccName);
        }
        /// <summary>
        /// Adds a blind carbon copy recipient to the current bcc dictionary
        /// </summary>
        /// <param name="bccName">The name of the recipient</param>
        /// <param name="bccAddress">The unique email address of the bcc recipient</param>
        public void AddBccAddress(string bccName, string bccAddress)
        {
            BccAddresses ??= new(1);
            BccAddresses.Add(bccAddress, bccName);
        }
        /// <summary>
        /// Adds a liquid template variable to be subsituted by the template
        /// renderer.
        /// </summary>
        /// <param name="varName">The unique name of the variable to add to the collection</param>
        /// <param name="varValue">The value if the variable that will be substituted into the template</param>
        public void AddVariable(string varName, string varValue)
        {
            Variables ??= new(1);
            Variables.Add(varName, varValue);
        }
    }
}