using QuestionsApi.Models;
using QuestionsApi.Services.Flashcards;

namespace QuestionsApi.Services;

// Idempotent, single-target seed for testing "system" (shared, admin-curated) flashcards.
// Unlike ContentPromotionCommand (cross-environment copy, source+target connections), this only
// ever writes to the one database the app is already configured against, using the exact same
// store methods a real user's create/edit path uses - just under the reserved FlashcardOwners.System
// identity - so seeded content is created/updated through the same validation and revision
// handling as any other deck/note.
public static class SeedFlashcardsCommand
{
    public static async Task<int> RunAsync(IConfiguration configuration, TextWriter output)
    {
        var mongo = new MongoDatabaseProvider(configuration);
        var scheduleStore = new FlashcardScheduleStore(mongo, new FsrsFlashcardScheduler());
        var deckStore = new FlashcardDeckStore(mongo);
        var noteStore = new FlashcardNoteStore(mongo, scheduleStore);

        var deck = await UpsertSystemDeckAsync(deckStore, "Step 3 Essentials", "Official curated review deck");
        await UpsertSystemNoteAsync(noteStore, deck.Id!, FlashcardTypes.Basic,
            "A 62-year-old woman presents with sudden, painless, monocular vision loss. What is the diagnosis?",
            "Central retinal artery occlusion", "\"Cherry-red spot\" on fundoscopy is the classic finding.");
        await UpsertSystemNoteAsync(noteStore, deck.Id!, FlashcardTypes.Basic,
            "Thyroid storm: correct order of pharmacologic treatment?",
            "Beta-blocker (propranolol) first -> thionamide (PTU/methimazole) -> iodine solution (started >=1hr after thionamide) -> glucocorticoids",
            "Giving iodine before the thionamide can fuel new hormone synthesis (Wolff-Chaikoff escape risk).");
        await UpsertSystemNoteAsync(noteStore, deck.Id!, FlashcardTypes.Cloze,
            "First-line treatment for uncomplicated hypertension in a Black patient is {{c1::a thiazide diuretic or calcium channel blocker}}.",
            "", "");

        await output.WriteLineAsync($"Seeded system flashcards into deck '{deck.Name}' ({deck.Id}).");
        return 0;
    }

    private static async Task<FlashcardDeck> UpsertSystemDeckAsync(FlashcardDeckStore deckStore, string name, string description)
    {
        var existing = await deckStore.GetByNameAsync(FlashcardOwners.System, FlashcardDeckStore.Normalize(name));
        var request = new UpsertFlashcardDeckRequest { Name = name, Description = description };
        var result = await deckStore.UpsertAsync(FlashcardOwners.System, request, existing?.Id);
        return result.Deck ?? existing ?? throw new InvalidOperationException($"failed to seed deck '{name}'");
    }

    private static async Task UpsertSystemNoteAsync(
        FlashcardNoteStore noteStore, string deckId, string type, string prompt, string answer, string extra)
    {
        var fingerprint = FlashcardNoteStore.Fingerprint(type, prompt, answer);
        var existingNotes = await noteStore.ListByDeckAsync(FlashcardOwners.System, deckId);
        var existing = existingNotes.FirstOrDefault(v => v.ContentFingerprint == fingerprint);
        var request = new UpsertFlashcardNoteRequest
        {
            DeckId = deckId,
            Type = type,
            Prompt = prompt,
            Answer = answer,
            Extra = extra,
            ExpectedRevision = existing?.Revision
        };
        await noteStore.UpsertAsync(FlashcardOwners.System, request, existing?.Id);
    }
}