package main

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

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

type Record struct {
	URI   string          `json:"uri"`
	CID   string          `json:"cid"`
	Value json.RawMessage `json:"value"`
}

type ListRecordsOutput struct {
	Records []struct {
		URI   string          `json:"uri"`
		CID   string          `json:"cid"`
		Value json.RawMessage `json:"value"`
	} `json:"records"`
	Cursor string `json:"cursor"`
}

type ListClient struct {
	client *xrpc.Client
	did    string
}

type DeleteClient struct {
	client *xrpc.Client
	did    string
}

func fetchRecords(ctx context.Context, handle, collection string, limit int, cursor string) (<-chan Record, <-chan error) {
	recordCh := make(chan Record, 100)
	errCh := make(chan error, 1)

	go func() {
		defer close(recordCh)
		defer close(errCh)

		currentCursor := cursor
		listClient, err := createListClient(ctx, handle)
		if err != nil {
			errCh <- err
			return
		}

		for {
			params := map[string]any{
				"repo":       listClient.did,
				"collection": collection,
				"limit":      limit,
			}
			if currentCursor != "" {
				params["cursor"] = currentCursor
			}

			var output ListRecordsOutput
			err = listClient.client.Do(ctx, xrpc.Query, "", "com.atproto.repo.listRecords", params, nil, &output)
			if err != nil {
				errCh <- fmt.Errorf("failed to list records: %w", err)
				return
			}

			for _, r := range output.Records {
				recordCh <- Record{
					URI:   r.URI,
					CID:   r.CID,
					Value: r.Value,
				}
			}

			if output.Cursor == "" {
				break
			}

			currentCursor = output.Cursor
		}
	}()

	return recordCh, errCh
}

func deleteRecords(ctx context.Context, client *xrpc.Client, uris []string) error {
	errCh := make(chan error, len(uris))
	wg := sync.WaitGroup{}

	for _, uri := range uris {
		wg.Go(func() {
			errCh <- deleteSingleRecord(ctx, client, uri)
		})
	}

	wg.Wait()
	close(errCh)

	for err := range errCh {
		if err != nil {
			fmt.Fprintf(os.Stderr, "Error: %v\n", err)
		}
	}

	return nil
}

func deleteSingleRecord(ctx context.Context, client *xrpc.Client, uriStr string) error {
	atUri, err := syntax.ParseATURI(uriStr)
	if err != nil {
		return fmt.Errorf("invalid URI: %w", err)
	}

	input := &atproto.RepoDeleteRecord_Input{
		Repo:       atUri.Authority().String(),
		Collection: atUri.Collection().String(),
		Rkey:       atUri.RecordKey().String(),
	}

	_, err = atproto.RepoDeleteRecord(ctx, client, input)
	if err != nil {
		return fmt.Errorf("failed to delete record: %w", err)
	}

	fmt.Printf("Deleted: %s\n", uriStr)
	return nil
}

func createAuthenticatedClient(ctx context.Context, handle, password string) (*DeleteClient, error) {
	atid, err := syntax.ParseAtIdentifier(handle)
	if err != nil {
		return nil, fmt.Errorf("invalid identifier: %w", err)
	}

	dir := identity.DefaultDirectory()
	ident, err := dir.Lookup(ctx, *atid)
	if err != nil {
		return nil, fmt.Errorf("failed to lookup identity: %w", err)
	}

	pdsEndpoint := ident.PDSEndpoint()
	if pdsEndpoint == "" {
		return nil, fmt.Errorf("no PDS endpoint found for %s", handle)
	}

	client := &xrpc.Client{
		Host: pdsEndpoint,
	}

	sessionInput := &atproto.ServerCreateSession_Input{
		Identifier: handle,
		Password:   password,
	}

	session, err := atproto.ServerCreateSession(ctx, client, sessionInput)
	if err != nil {
		return nil, fmt.Errorf("failed to create session: %w", err)
	}

	client.Auth = &xrpc.AuthInfo{
		AccessJwt:  session.AccessJwt,
		RefreshJwt: session.RefreshJwt,
		Handle:     session.Handle,
		Did:        session.Did,
	}

	return &DeleteClient{
		client: client,
		did:    session.Did,
	}, nil
}

func createListClient(ctx context.Context, handle string) (*ListClient, error) {
	atid, err := syntax.ParseAtIdentifier(handle)
	if err != nil {
		return nil, fmt.Errorf("invalid identifier: %w", err)
	}

	dir := identity.DefaultDirectory()
	ident, err := dir.Lookup(ctx, *atid)
	if err != nil {
		return nil, fmt.Errorf("failed to lookup identity: %w", err)
	}

	pdsEndpoint := ident.PDSEndpoint()
	if pdsEndpoint == "" {
		return nil, fmt.Errorf("no PDS endpoint found for %s", handle)
	}

	client := &xrpc.Client{
		Host: pdsEndpoint,
	}

	return &ListClient{
		client: client,
		did:    ident.DID.String(),
	}, nil
}