package admin

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

	"github.com/gin-gonic/gin"
	"github.com/superseriousbusiness/gotosocial/internal/api"
	"github.com/superseriousbusiness/gotosocial/internal/api/model"
	"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.
//
// Note that 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
// - 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.
//     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`.
//       Note that 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 {
		api.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)
		api.ErrorHandler(c, gtserror.NewErrorForbidden(err, err.Error()), m.processor.InstanceGet)
		return
	}

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

	form := &model.DomainBlockCreateRequest{}
	if err := c.ShouldBind(form); err != nil {
		api.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)
		api.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 {
			api.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 {
		api.ErrorHandler(c, errWithCode, m.processor.InstanceGet)
		return
	}
	c.JSON(http.StatusOK, domainBlock)
}

func validateCreateDomainBlock(form *model.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
}