package main

import (
	"context"
	"encoding/json"
	"fmt"

	"github.com/bluesky-social/indigo/api/atproto"
	"github.com/bluesky-social/indigo/api/bsky"
	"github.com/bluesky-social/indigo/atproto/identity"
	"github.com/bluesky-social/indigo/atproto/syntax"
	"github.com/bluesky-social/indigo/xrpc"
)

func findUserPDS(ctx context.Context, did string) (string, error) {
	id, err := identity.DefaultDirectory().LookupDID(ctx, syntax.DID(did))
	if err != nil {
		return "", err
	}
	pdsURI := id.PDSEndpoint()
	if len(pdsURI) == 0 {
		return "", fmt.Errorf("no PDS URL was found in identity document")
	}

	return pdsURI, nil
}

func fetchRecords[v any](ctx context.Context, xrpcClient *xrpc.Client, collection, did string, extractFn func(v) string) (Set[string], error) {
	all := make(Set[string])
	cursor := ""

	for {
		// todo: ratelimits?? idk what this does for those
		out, err := atproto.RepoListRecords(ctx, xrpcClient, collection, cursor, 100, did, false)
		if err != nil {
			return nil, err
		}

		for _, record := range out.Records {
			raw, _ := record.Value.MarshalJSON()
			var val v
			if err := json.Unmarshal(raw, &val); err != nil {
				return nil, err
			}
			s := extractFn(val)
			if len(s) > 0 {
				all[s] = struct{}{}
			}
		}

		if out.Cursor == nil || *out.Cursor == "" {
			break
		}
		cursor = *out.Cursor
	}

	return all, nil
}

func fetchReposts(ctx context.Context, xrpcClient *xrpc.Client, did string) (Set[string], error) {
	return fetchRecords(ctx, xrpcClient, "app.bsky.feed.repost", did, func(v bsky.FeedRepost) string { return v.Subject.Uri })
}

func fetchFollows(ctx context.Context, xrpcClient *xrpc.Client, did string) (Set[string], error) {
	return fetchRecords(ctx, xrpcClient, "app.bsky.graph.follow", did, func(v bsky.GraphFollow) string { return v.Subject })
}