using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Windows.Forms;
using AudibleApi;
using AudibleUtilities;

namespace LibationWinForms.Dialogs
{
	public partial class AccountsDialog : Form
	{
		private const string COL_Delete = nameof(DeleteAccount);
		private const string COL_Export = nameof(ExportAccount);
		private const string COL_LibraryScan = nameof(LibraryScan);
		private const string COL_AccountId = nameof(AccountId);
		private const string COL_AccountName = nameof(AccountName);
		private const string COL_Locale = nameof(Locale);

		public AccountsDialog()
		{
			InitializeComponent();

			dataGridView1.Columns[COL_AccountName].AutoSizeMode = DataGridViewAutoSizeColumnMode.Fill;

			populateDropDown();

			populateGridValues();
			this.SetLibationIcon();
		}

		private void populateDropDown()
			=> (dataGridView1.Columns[COL_Locale] as DataGridViewComboBoxColumn).DataSource
				= Localization.Locales
					.Select(l => l.Name)
					.OrderBy(a => a).ToList();

		private void populateGridValues()
		{
			// WARNING: accounts persister will write ANY EDIT to object immediately to file
			// here: copy strings and dispose of persister
			// only persist in 'save' step
			using var persister = AudibleApiStorage.GetAccountsSettingsPersister();
			var accounts = persister.AccountsSettings.Accounts;
			if (!accounts.Any())
				return;

			foreach (var account in accounts)
				AddAccountToGrid(account);
		}

		private void AddAccountToGrid(Account account)
		{
			var row = dataGridView1.Rows.Add(
				"X",
				"Export",
				account.LibraryScan,
				account.AccountId,
				account.Locale.Name,
				account.AccountName);

			dataGridView1[COL_Export, row].ToolTipText = "Export account authorization to audible-cli";
		}

		private void dataGridView1_DefaultValuesNeeded(object sender, DataGridViewRowEventArgs e)
		{
			e.Row.Cells[COL_Delete].Value = "X";
			e.Row.Cells[COL_LibraryScan].Value = true;
		}

		private void DataGridView1_CellContentClick(object sender, DataGridViewCellEventArgs e)
		{
			var dgv = (DataGridView)sender;

			var col = dgv.Columns[e.ColumnIndex];
			if (col is DataGridViewButtonColumn && e.RowIndex >= 0)
			{
				var row = dgv.Rows[e.RowIndex];
				switch (col.Name)
				{
					case COL_Delete:
						// if final/edit row: do nothing
						if (e.RowIndex < dgv.RowCount - 1)
							dgv.Rows.Remove(row);
						break;
					case COL_Export:
						// if final/edit row: do nothing
						if (e.RowIndex < dgv.RowCount - 1)
							Export((string)row.Cells[COL_AccountId].Value, (string)row.Cells[COL_Locale].Value);
						break;
						//case COL_MoveUp:
						//	// if top: do nothing
						//	if (e.RowIndex < 1)
						//		break;
						//	dgv.Rows.Remove(row);
						//	dgv.Rows.Insert(e.RowIndex - 1, row);
						//	break;
						//case COL_MoveDown:
						//	// if final/edit row or bottom filter row: do nothing
						//	if (e.RowIndex >= dgv.RowCount - 2)
						//		break;
						//	dgv.Rows.Remove(row);
						//	dgv.Rows.Insert(e.RowIndex + 1, row);
						//	break;
				}
			}
		}

		private void cancelBtn_Click(object sender, EventArgs e)
		{
			this.DialogResult = DialogResult.Cancel;
			this.Close();
		}

		private class AccountDto
		{
			public string AccountId { get; set; }
			public string AccountName { get; set; }
			public string LocaleName { get; set; }
			public bool LibraryScan { get; set; }
		}

		private void saveBtn_Click(object sender, EventArgs e)
		{
			try
			{
				if (!inputIsValid())
					return;

				// without transaction, accounts persister will write ANY EDIT immediately to file
				using var persister = AudibleApiStorage.GetAccountsSettingsPersister();

				persister.BeginTransation();
				persist(persister.AccountsSettings);
				persister.CommitTransation();

				this.DialogResult = DialogResult.OK;
				this.Close();
			}
			catch (Exception ex)
			{
				MessageBoxLib.ShowAdminAlert(this, "Error attempting to save accounts", "Error saving accounts", ex);
			}
		}

		private bool inputIsValid()
		{
			var dtos = getRowDtos();

			foreach (var dto in dtos)
			{
				if (string.IsNullOrWhiteSpace(dto.AccountId))
				{
					MessageBox.Show(this, "Account id cannot be blank. Please enter an account id for all accounts.", "Blank account", MessageBoxButtons.OK, MessageBoxIcon.Error);
					return false;
				}

				if (string.IsNullOrWhiteSpace(dto.LocaleName))
				{
					MessageBox.Show(this, "Please select a locale (i.e.: country or region) for all accounts.", "Blank region", MessageBoxButtons.OK, MessageBoxIcon.Error);
					return false;
				}
			}

			return true;
		}

		private void persist(AccountsSettings accountsSettings)
		{
			var existingAccounts = accountsSettings.Accounts;
			var dtos = getRowDtos();

			// editing account id is a special case. an account is defined by its account id, therefore this is really a different account. the user won't care about this distinction though.
			// these will be caught below by normal means and re-created minus the convenience of persisting identity tokens

			// delete
			for (var i = existingAccounts.Count - 1; i >= 0; i--)
			{
				var existing = existingAccounts[i];
				if (!dtos.Any(dto =>
					dto.AccountId?.ToLower().Trim() == existing.AccountId.ToLower()
					&& dto.LocaleName == existing.Locale?.Name))
				{
					accountsSettings.Delete(existing);
				}
			}

			// upsert each. validation occurs through Account and AccountsSettings
			foreach (var dto in dtos)
			{
				var acct = accountsSettings.Upsert(dto.AccountId, dto.LocaleName);
				acct.LibraryScan = dto.LibraryScan;
				acct.AccountName
					= string.IsNullOrWhiteSpace(dto.AccountName)
					? $"{dto.AccountId} - {dto.LocaleName}"
					: dto.AccountName.Trim();
			}
		}

		private List<AccountDto> getRowDtos()
			=> dataGridView1.Rows
				.Cast<DataGridViewRow>()
				.Where(r => !r.IsNewRow)
				.Select(r => new AccountDto
				{
					AccountId = (string)r.Cells[COL_AccountId].Value,
					AccountName = (string)r.Cells[COL_AccountName].Value,
					LocaleName = (string)r.Cells[COL_Locale].Value,
					LibraryScan = (bool)r.Cells[COL_LibraryScan].Value
				})
				.ToList();

		private string GetAudibleCliAppDataPath()
			=> Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "Audible");

		private void Export(string accountId, string locale)
		{
			// without transaction, accounts persister will write ANY EDIT immediately to file
			using var persister = AudibleApiStorage.GetAccountsSettingsPersister();

			var account = persister.AccountsSettings.Accounts.FirstOrDefault(a => a.AccountId == accountId && a.Locale.Name == locale);

			if (account is null)
				return;

			if (account.IdentityTokens?.IsValid != true)
			{
				MessageBox.Show(this, "This account hasn't been authenticated yet. First scan your library to log into your account, then try exporting again.", "Account Not Authenticated");
				return;
			}

			SaveFileDialog sfd = new();
			sfd.Filter = "JSON File|*.json";

			string audibleAppDataDir = GetAudibleCliAppDataPath();

			if (Directory.Exists(audibleAppDataDir))
				sfd.InitialDirectory = audibleAppDataDir;

			if (sfd.ShowDialog() != DialogResult.OK) return;

			try
			{
				var mkbAuth = Mkb79Auth.FromAccount(account);
				var jsonText = mkbAuth.ToJson();

				File.WriteAllText(sfd.FileName, jsonText);

				MessageBox.Show(this, $"Successfully exported {account.AccountName} to\r\n\r\n{sfd.FileName}", "Success!");
			}
			catch (Exception ex)
			{
				MessageBoxLib.ShowAdminAlert(
					this,
					$"An error occurred while exporting account:\r\n{account.AccountName}",
					"Error Exporting Account",
					ex);
			}
		}

		private async void importBtn_Click(object sender, EventArgs e)
		{
			OpenFileDialog ofd = new();
			ofd.Filter = "JSON File|*.json";
			ofd.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);

			string audibleAppDataDir = GetAudibleCliAppDataPath();

			if (Directory.Exists(audibleAppDataDir))
				ofd.InitialDirectory = audibleAppDataDir;

			if (ofd.ShowDialog() != DialogResult.OK) return;

			try
			{
				var jsonText = File.ReadAllText(ofd.FileName);
				var mkbAuth = Mkb79Auth.FromJson(jsonText);
				var account = await mkbAuth.ToAccountAsync();

				// without transaction, accounts persister will write ANY EDIT immediately to file
				using var persister = AudibleApiStorage.GetAccountsSettingsPersister();

				if (persister.AccountsSettings.Accounts.Any(a => a.AccountId == account.AccountId && a.IdentityTokens.Locale.Name == account.Locale.Name))
				{
					MessageBox.Show(this, $"An account with that account id and country already exists.\r\n\r\nAccount ID: {account.AccountId}\r\nCountry: {account.Locale.Name}", "Cannot Add Duplicate Account");
					return;
				}

				persister.AccountsSettings.Add(account);

				AddAccountToGrid(account);
			}
			catch (Exception ex)
			{
				MessageBoxLib.ShowAdminAlert(
						this,
						$"An error occurred while importing an account from:\r\n{ofd.FileName}\r\n\r\nIs the file encrypted?",
						"Error Importing Account",
						ex);
			}
		}
	}
}