using Blahblah.FlowerApp.Data.Model;
using Microsoft.Extensions.Logging;
using SQLite;

namespace Blahblah.FlowerApp.Data;

public class FlowerDatabase
{
    private SQLiteAsyncConnection database = null!;

    private readonly ILogger logger;

    public FlowerDatabase(ILogger<FlowerDatabase> logger)
    {
        this.logger = logger;

        Task.Run(async () =>
        {
            try
            {
                await Setup();
            }
            catch (Exception ex)
            {
                logger.LogError("error occurs on setup, {error}", ex);
            }
        });
    }

    private Dictionary<int, NamedItem>? categories;

    private Dictionary<int, EventItem>? events;

    public string Category(int categoryId)
    {
        if (categories?.TryGetValue(categoryId, out var category) == true)
        {
            return category.Name;
        }
        return Constants.CategoryOther;
    }

    public string Event(int eventId)
    {
        if (events?.TryGetValue(eventId, out var @event) == true)
        {
            return @event.Name;
        }
        return Constants.EventUnknown;
    }

    private async Task Setup()
    {
        await Init();

#if DEBUG
        Constants.SetAuthorization("RF4mfoUur0vHtWzHwD42ka0FhIfGaPnBxoQgrXOYEDg=");
#else
        var token = await database.Table<ParamItem>().FirstOrDefaultAsync(p => p.Code == Constants.LastTokenName);
        if (token != null)
        {
            Constants.SetAuthorization(token.Value);
        }
#endif

        var version = await database.Table<ParamItem>().FirstOrDefaultAsync(p => p.Code == Constants.ApiVersionName);
        var definition = await Constants.Initialize(logger, version?.Value);

        if (definition != null)
        {
            categories = definition.Categories;
            events = definition.Events;

            logger.LogInformation("new version founded, from ({from}) to ({to})", version?.Value, definition.ApiVersion);

            if (version == null)
            {
                version = new ParamItem
                {
                    Code = Constants.ApiVersionName,
                    Value = definition.ApiVersion
                };
            }
            else
            {
                version.Value = definition.ApiVersion;
            }
            await database.InsertOrReplaceAsync(version);

            // replace local definitions
            await database.DeleteAllAsync<DefinitionItem>();

            var defs = new List<DefinitionItem>();
            foreach (var category in definition.Categories)
            {
                defs.Add(new DefinitionItem
                {
                    DefinitionType = 0,
                    DefinitionId = category.Key,
                    Name = category.Value.Name,
                    Description = category.Value.Description
                });
            }
            foreach (var @event in definition.Events)
            {
                defs.Add(new DefinitionItem
                {
                    DefinitionType = 1,
                    DefinitionId = @event.Key,
                    Name = @event.Value.Name,
                    Description = @event.Value.Description,
                    Unique = @event.Value.Unique
                });
            }
            var rows = await database.InsertAllAsync(defs);
            logger.LogInformation("{count} definitions, {rows} rows inserted", defs.Count, rows);
        }
        else
        {
            // use local definitions
            var defs = await database.Table<DefinitionItem>().ToListAsync();
            var cates = new Dictionary<int, NamedItem>();
            var evts = new Dictionary<int, EventItem>();
            foreach (var d in defs)
            {
                if (d.DefinitionType == 0)
                {
                    // category
                    cates[d.DefinitionId] = new NamedItem(d.Name, d.Description);
                }
                else if (d.DefinitionType == 1)
                {
                    // event
                    evts[d.DefinitionId] = new EventItem(d.Name, d.Description, d.Unique ?? false);
                }
            }
            categories = cates;
            events = evts;
        }
    }

    private async Task Init()
    {
        if (database is not null)
        {
            return;
        }

        database = new SQLiteAsyncConnection(Constants.DatabasePath, Constants.SQLiteFlags);

#if DEBUG
        var result =
#endif
            await database.CreateTablesAsync(CreateFlags.None,
                typeof(FlowerItem),
                typeof(RecordItem),
                typeof(PhotoItem),
                typeof(UserItem),
                typeof(DefinitionItem),
                typeof(ParamItem));

#if DEBUG
        foreach (var item in result.Results)
        {
            logger.LogInformation("create table {table}, result: {result}", item.Key, item.Value);
        }
#endif
    }

    public async Task<FlowerItem[]> GetFlowers()
    {
        await Init();
        return await database.Table<FlowerItem>().ToArrayAsync();
    }
}