/*
   GoToSocial
   Copyright (C) 2021-2022 GoToSocial Authors admin@gotosocial.org

   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 admin

import (
	"errors"
	"fmt"
	"net/http"
	"strconv"

	"github.com/gin-gonic/gin"
	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
	apiutil "github.com/superseriousbusiness/gotosocial/internal/api/util"
	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
	"github.com/superseriousbusiness/gotosocial/internal/oauth"
)

// DomainBlocksPOSTHandler swagger:operation POST /api/v1/admin/domain_blocks domainBlockCreate
//
// Create one or more domain blocks, from a string or a file.
//
// You have two options when using this endpoint: either you can set `import` to `true` and
// upload a file containing multiple domain blocks, JSON-formatted, or you can leave import as
// `false`, and just add one domain block.
//
// The format of the json file should be something like: `[{"domain":"example.org"},{"domain":"whatever.com","public_comment":"they smell"}]`
//
//	---
//	tags:
//	- admin
//
//	consumes:
//	- multipart/form-data
//
//	produces:
//	- application/json
//
//	parameters:
//	-
//		name: import
//		in: query
//		description: >-
//			Signal that a list of domain blocks is being imported as a file.
//			If set to `true`, then 'domains' must be present as a JSON-formatted file.
//			If set to `false`, then `domains` will be ignored, and `domain` must be present.
//		type: boolean
//		default: false
//	-
//		name: domains
//		in: formData
//		description: >-
//			JSON-formatted list of domain blocks to import.
//			This is only used if `import` is set to `true`.
//		type: file
//	-
//		name: domain
//		in: formData
//		description: >-
//			Single domain to block.
//			Used only if `import` is not `true`.
//		type: string
//	-
//		name: obfuscate
//		in: formData
//		description: >-
//			Obfuscate the name of the domain when serving it publicly.
//			Eg., `example.org` becomes something like `ex***e.org`.
//			Used only if `import` is not `true`.
//		type: boolean
//	-
//		name: public_comment
//		in: formData
//		description: >-
//			Public comment about this domain block.
//			This will be displayed alongside the domain block if you choose to share blocks.
//			Used only if `import` is not `true`.
//		type: string
//	-
//		name: private_comment
//		in: formData
//		description: >-
//			Private comment about this domain block. Will only be shown to other admins, so this
//			is a useful way of internally keeping track of why a certain domain ended up blocked.
//			Used only if `import` is not `true`.
//		type: string
//
//	security:
//	- OAuth2 Bearer:
//		- admin
//
//	responses:
//		'200':
//			description: >-
//				The newly created domain block, if `import` != `true`.
//				If a list has been imported, then an `array` of newly created domain blocks will be returned instead.
//			schema:
//				"$ref": "#/definitions/domainBlock"
//		'400':
//			description: bad request
//		'401':
//			description: unauthorized
//		'403':
//			description: forbidden
//		'404':
//			description: not found
//		'406':
//			description: not acceptable
//		'500':
//			description: internal server error
func (m *Module) DomainBlocksPOSTHandler(c *gin.Context) {
	authed, err := oauth.Authed(c, true, true, true, true)
	if err != nil {
		apiutil.ErrorHandler(c, gtserror.NewErrorUnauthorized(err, err.Error()), m.processor.InstanceGet)
		return
	}

	if !*authed.User.Admin {
		err := fmt.Errorf("user %s not an admin", authed.User.ID)
		apiutil.ErrorHandler(c, gtserror.NewErrorForbidden(err, err.Error()), m.processor.InstanceGet)
		return
	}

	if _, err := apiutil.NegotiateAccept(c, apiutil.JSONAcceptHeaders...); err != nil {
		apiutil.ErrorHandler(c, gtserror.NewErrorNotAcceptable(err, err.Error()), m.processor.InstanceGet)
		return
	}

	imp := false
	importString := c.Query(ImportQueryKey)
	if importString != "" {
		i, err := strconv.ParseBool(importString)
		if err != nil {
			err := fmt.Errorf("error parsing %s: %s", ImportQueryKey, err)
			apiutil.ErrorHandler(c, gtserror.NewErrorBadRequest(err, err.Error()), m.processor.InstanceGet)
			return
		}
		imp = i
	}

	form := &apimodel.DomainBlockCreateRequest{}
	if err := c.ShouldBind(form); err != nil {
		apiutil.ErrorHandler(c, gtserror.NewErrorBadRequest(err, err.Error()), m.processor.InstanceGet)
		return
	}

	if err := validateCreateDomainBlock(form, imp); err != nil {
		err := fmt.Errorf("error validating form: %s", err)
		apiutil.ErrorHandler(c, gtserror.NewErrorBadRequest(err, err.Error()), m.processor.InstanceGet)
		return
	}

	if imp {
		// we're importing multiple blocks
		domainBlocks, errWithCode := m.processor.AdminDomainBlocksImport(c.Request.Context(), authed, form)
		if errWithCode != nil {
			apiutil.ErrorHandler(c, errWithCode, m.processor.InstanceGet)
			return
		}
		c.JSON(http.StatusOK, domainBlocks)
		return
	}

	// we're just creating one block
	domainBlock, errWithCode := m.processor.AdminDomainBlockCreate(c.Request.Context(), authed, form)
	if errWithCode != nil {
		apiutil.ErrorHandler(c, errWithCode, m.processor.InstanceGet)
		return
	}
	c.JSON(http.StatusOK, domainBlock)
}

func validateCreateDomainBlock(form *apimodel.DomainBlockCreateRequest, imp bool) error {
	if imp {
		if form.Domains.Size == 0 {
			return errors.New("import was specified but list of domains is empty")
		}
	} else {
		// add some more validation here later if necessary
		if form.Domain == "" {
			return errors.New("empty domain provided")
		}
	}

	return nil
}