module Degenz.Store

open System.Threading.Tasks
open DSharpPlus.Entities
open DSharpPlus
open DSharpPlus.EventArgs
open DSharpPlus.SlashCommands
open Degenz
open Degenz.Messaging
open Degenz.PlayerInteractions

let checkHasSufficientFunds (item : Item) player =
    if player.Bank - item.Price >= 0<GBT>
       then Ok player
       else Error $"You do not have sufficient funds to buy this item! Current balance: {player.Bank} GBT"

let checkAlreadyOwnsItem (item : Item) player =
    if player.Inventory |> List.exists (fun w -> item.Id = w.Id)
        then Error $"You already own {item.Name}!"
        else Ok player

let checkSoldItemAlready item player =
    if player.Inventory |> List.exists (fun i -> item.Id = i.Id)
        then Ok player
        else Error $"{item.Name} not found in your inventory! Looks like you sold it already."

let checkHasItemsInArsenal itemType items player =
    if List.isEmpty items |> not
        then Ok player
        else Error $"You currently have no {itemType} in your arsenal to sell!"

let buy getItems (ctx : IDiscordContext) =
    executePlayerAction ctx (fun player -> async {
        let itemStore = Embeds.getBuyItemsEmbed (getItems player.Inventory) (getItems Armory.battleItems)
        do! ctx.FollowUp itemStore |> Async.AwaitTask
    })

let sell itemType getItems (ctx : IDiscordContext) =
    executePlayerAction ctx (fun player -> async {
        let items = getItems player
        match checkHasItemsInArsenal itemType items player with
        | Ok _ -> let itemStore = Embeds.getSellEmbed items
                  do! ctx.FollowUp(itemStore) |> Async.AwaitTask
        | Error e -> do! sendFollowUpMessage ctx e
    })

// TODO: When you buy a shield, prompt the user to activate it
let handleBuyItem (ctx : IDiscordContext) itemId =
    executePlayerAction ctx (fun player -> async {
        let item = Armory.getItem itemId
        do! player
            |> checkHasSufficientFunds item
            >>= checkAlreadyOwnsItem item
            |> handleResultWithResponse ctx (fun player -> async {
                let newBalance = player.Bank - item.Price
                let p = { player with Bank = newBalance ; Inventory = item::player.Inventory }
                do! DbService.updatePlayer GuildEnvironment.pgDb p |> Async.Ignore
                do! sendFollowUpMessage ctx $"Successfully purchased {item.Name}! You now have {newBalance} 💰$GBT remaining"
            })
    })

let handleSell (ctx : IDiscordContext) itemId =
    executePlayerAction ctx (fun player -> async {
        let item = Armory.getItem itemId
        do!
        player
        |> checkSoldItemAlready item
        |> handleResultWithResponse ctx (fun player -> async {
            let updatedPlayer = {
                player with
                    Bank = player.Bank + item.Price
                    Inventory = player.Inventory |> List.filter (fun i -> i.Id <> itemId)
            }
            do!
            [ DbService.updatePlayer GuildEnvironment.pgDb updatedPlayer |> Async.Ignore
              DbService.removeShieldEvent GuildEnvironment.pgDb updatedPlayer.DiscordId itemId |> Async.Ignore
              sendFollowUpMessage ctx $"Sold {item.Type} {item.Name} for {item.Price}! Current Balance: {updatedPlayer.Bank}" ]
            |> Async.Parallel
            |> Async.Ignore
        })
    })

let handleStoreEvents (_ : DiscordClient) (event : ComponentInteractionCreateEventArgs) =
    let ctx = DiscordEventContext event :> IDiscordContext
    let id = ctx.GetInteractionId()
    let itemId = int <| id.Split("-").[1]
    match id with
    | id when id.StartsWith("Buy") -> handleBuyItem ctx itemId
    | id when id.StartsWith("Sell") -> handleSell ctx itemId
    | _ ->
        task {
            let builder = DiscordInteractionResponseBuilder()
            builder.IsEphemeral <- true
            builder.Content <- $"Incorrect Action identifier {id}"
            do! ctx.Respond(InteractionResponseType.ChannelMessageWithSource, builder) |> Async.AwaitTask
        }

type Store() =
    inherit ApplicationCommandModule ()

    let enforceChannel (ctx : IDiscordContext) (storeFn : IDiscordContext -> Task) =
        match ctx.GetChannel().Id with
        | id when id = GuildEnvironment.channelArmory -> storeFn ctx
        | _ ->
            task {
                let msg = $"You must go to <#{GuildEnvironment.channelArmory}> channel to buy or sell weapons"
                do! Messaging.sendSimpleResponse ctx msg
            }

    [<SlashCommand("buy-hack", "Purchase a hack attack you can use to earn GoodBoyTokenz")>]
    member _.BuyHack (ctx : InteractionContext) = enforceChannel (DiscordInteractionContext(ctx)) (buy Armory.getHackItems)

    [<SlashCommand("buy-shield", "Purchase a hack shield so you can protect your GoodBoyTokenz")>]
    member this.BuyShield (ctx : InteractionContext) = enforceChannel (DiscordInteractionContext(ctx)) (buy Armory.getShieldItems)

    [<SlashCommand("sell-hack", "Sell a hack for GoodBoyTokenz")>]
    member this.SellHack (ctx : InteractionContext) = enforceChannel (DiscordInteractionContext(ctx)) (sell "Hacks" Player.getHackItems)

    [<SlashCommand("sell-shield", "Sell a shield for GoodBoyTokenz")>]
    member this.SellShield (ctx : InteractionContext) = enforceChannel (DiscordInteractionContext(ctx)) (sell "Shields" Player.getShieldItems)