// GoToSocial
// Copyright (C) GoToSocial Authors admin@gotosocial.org
// SPDX-License-Identifier: AGPL-3.0-or-later
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package account

import (
	"context"
	"errors"
	"net/url"

	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
	"github.com/superseriousbusiness/gotosocial/internal/db"
	"github.com/superseriousbusiness/gotosocial/internal/gtscontext"
	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
	"github.com/superseriousbusiness/gotosocial/internal/log"
)

// Get processes the given request for account information.
func (p *Processor) Get(ctx context.Context, requestingAccount *gtsmodel.Account, targetAccountID string) (*apimodel.Account, gtserror.WithCode) {
	targetAccount, err := p.state.DB.GetAccountByID(ctx, targetAccountID)
	if err != nil {
		if errors.Is(err, db.ErrNoEntries) {
			err := gtserror.New("account not found")
			return nil, gtserror.NewErrorNotFound(err)
		}
		err := gtserror.Newf("db error getting account: %w", err)
		return nil, gtserror.NewErrorInternalError(err)
	}

	blocked, err := p.state.DB.IsEitherBlocked(ctx, requestingAccount.ID, targetAccount.ID)
	if err != nil {
		err := gtserror.Newf("db error checking blocks: %w", err)
		return nil, gtserror.NewErrorInternalError(err)
	}

	if blocked {
		apiAccount, err := p.converter.AccountToAPIAccountBlocked(ctx, targetAccount)
		if err != nil {
			err := gtserror.Newf("error converting account: %w", err)
			return nil, gtserror.NewErrorInternalError(err)
		}
		return apiAccount, nil
	}

	if targetAccount.Domain != "" {
		targetAccountURI, err := url.Parse(targetAccount.URI)
		if err != nil {
			err := gtserror.Newf("error parsing account URI: %w", err)
			return nil, gtserror.NewErrorInternalError(err)
		}

		// Perform a last-minute fetch of target account to
		// ensure remote account header / avatar is cached.
		latest, _, err := p.federator.GetAccountByURI(
			gtscontext.SetFastFail(ctx),
			requestingAccount.Username,
			targetAccountURI,
		)
		if err != nil {
			log.Errorf(ctx, "error fetching latest target account: %v", err)
		} else {
			// Use latest account model.
			targetAccount = latest
		}
	}

	var apiAccount *apimodel.Account
	if targetAccount.ID == requestingAccount.ID {
		// This is requester's own account,
		// show additional details.
		apiAccount, err = p.converter.AccountToAPIAccountSensitive(ctx, targetAccount)
	} else {
		// This is a different account,
		// show the "public" view.
		apiAccount, err = p.converter.AccountToAPIAccountPublic(ctx, targetAccount)
	}
	if err != nil {
		err := gtserror.Newf("error converting account: %w", err)
		return nil, gtserror.NewErrorInternalError(err)
	}

	return apiAccount, nil
}

// GetWeb returns the web model of a local account by username.
func (p *Processor) GetWeb(ctx context.Context, username string) (*apimodel.Account, gtserror.WithCode) {
	targetAccount, err := p.state.DB.GetAccountByUsernameDomain(ctx, username, "")
	if err != nil {
		if errors.Is(err, db.ErrNoEntries) {
			err := gtserror.New("account not found")
			return nil, gtserror.NewErrorNotFound(err)
		}
		err := gtserror.Newf("db error getting account: %w", err)
		return nil, gtserror.NewErrorInternalError(err)
	}

	webAccount, err := p.converter.AccountToWebAccount(ctx, targetAccount)
	if err != nil {
		err := gtserror.Newf("error converting account: %w", err)
		return nil, gtserror.NewErrorInternalError(err)
	}

	return webAccount, nil
}

// GetCustomCSSForUsername returns custom css for the given local username.
func (p *Processor) GetCustomCSSForUsername(ctx context.Context, username string) (string, gtserror.WithCode) {
	customCSS, err := p.state.DB.GetAccountCustomCSSByUsername(ctx, username)
	if err != nil {
		if errors.Is(err, db.ErrNoEntries) {
			return "", gtserror.NewErrorNotFound(gtserror.New("account not found"))
		}
		return "", gtserror.NewErrorInternalError(gtserror.Newf("db error: %w", err))
	}

	return customCSS, nil
}