package accounts

import (
	"errors"
	"fmt"
	"strconv"
	"strings"

	"github.com/gin-gonic/gin"
	"github.com/google/uuid"

	"ruben/inventory2/internal/consts"
	"ruben/inventory2/internal/domains/accounts"
	"ruben/inventory2/internal/logging"
	"ruben/inventory2/internal/server/auth"
	"ruben/inventory2/internal/server/response"
	"ruben/inventory2/internal/server/sse"
)

type accountSubrouter struct {
	log   *logging.Logger
	accts *accounts.Store
	pub   *sse.UpdateNotificationPublisher
}

func Routes(
	r *gin.RouterGroup,
	logger *logging.Logger,
	accts *accounts.Store,
	pub *sse.UpdateNotificationPublisher,
) {
	as := &accountSubrouter{
		log:   logger,
		accts: accts,
		pub:   pub,
	}

	r.POST("", response.Handler(as.createAccount))
	r.PUT("/:acctID/platforms/:platform/order-index", pub.Publish("/:acctID/platforms"), response.Handler(as.setOrderOfPlatformOnAccountPage))

	syncGroups := r.Group("/:acctID/inventory/sync-groups")
	syncGroups.POST("", pub.Publish("/:acctID/inventory/sync-groups"), response.Handler(as.saveNewSyncGroup))

	draftListings := syncGroups.Group("/draft/listings", pub.Publish("/:acctID/inventory/sync-groups/draft/listings"))
	draftListings.POST("", response.Handler(as.createSyncGroupListingDraft))
	draftListings.PUT("/:orderIndex/shop", response.Handler(as.setShopInSyncGroupListingDraft))
	draftListings.PUT("/:orderIndex/listing", response.Handler(as.setListingInSyncGroupListingDraft))
	draftListings.DELETE("/:orderIndex", response.Handler(as.deleteSyncGroupListingDraft))
}

// POST /
func (s *accountSubrouter) createAccount(c *gin.Context) (response.Response, error) {
	r := c.Request
	ctx := r.Context()

	// TODO: get email from the user's account profile (how?) - will need to flesh out the account creation process later on
	email := uuid.NewString() + "@example.com"

	userID := auth.GetIdentity(ctx).User.UserID

	_, err := s.accts.CreateAccount(ctx, userID, email)
	if err != nil {
		if errors.Is(err, consts.ErrConflict) {
			return nil, response.Conflict().
				Msg("user already has an account")
		}
		return nil, response.Errorf("failed to create account: %w", err)
	}

	return response.StatusCreated().
		// force a reload to ensure an sse connection is made.
		// user should automatically be redirected to the appropriate page based on their current location and/or login/account statuses.
		HXRefresh("true"), nil
}

// POST /:acctID/inventory/sync-groups/draft/listings
func (s *accountSubrouter) createSyncGroupListingDraft(c *gin.Context) (response.Response, error) {
	r := c.Request
	ctx := r.Context()
	acctID := auth.GetIdentity(ctx).Account.AccountID

	if _, err := s.accts.CreateSyncGroupListingDraft(ctx, acctID); err != nil {
		return nil, response.Errorf("failed to create new listing draft: %w", err)
	}

	return response.StatusCreated(), nil
}

// PUT /:acctID/inventory/sync-groups/draft/listings/{orderIndex}/shop
// @platform 	string
// @shopID 		string
func (s *accountSubrouter) setShopInSyncGroupListingDraft(c *gin.Context) (response.Response, error) {
	r := c.Request
	ctx := r.Context()
	acctID := auth.GetIdentity(ctx).Account.AccountID

	orderIndex, err := getOrderIndexForSyncGroupListingDraftFromPath(c)
	if err != nil {
		return nil, err
	}

	platformStr := r.FormValue("platform")
	platform, err := accounts.NewPlatform(platformStr)
	if err != nil {
		return nil, response.BadRequest().
			Msgf("unrecognized platform: %s", platformStr)
	}

	shopID := r.FormValue("shop-id")
	if shopID == "" {
		return nil, response.BadRequest().
			Msg("no shop-id provided")
	}

	if err := s.accts.SetShopInSyncGroupListingDraft(ctx, acctID, orderIndex, platform, shopID); err != nil {
		return nil, response.Errorf("failed to set shop: %w", response.ErrorFromConstant(err))
	}

	return response.StatusOK(), nil
}

// PUT /:acctID/inventory/sync-groups/draft/listings/{orderIndex}/listing
func (s *accountSubrouter) setListingInSyncGroupListingDraft(c *gin.Context) (response.Response, error) {
	r := c.Request
	ctx := r.Context()
	acctID := auth.GetIdentity(ctx).Account.AccountID

	orderIndex, err := getOrderIndexForSyncGroupListingDraftFromPath(c)
	if err != nil {
		return nil, err
	}

	listingID := r.FormValue("listing-id")
	if listingID == "" {
		return nil, response.BadRequest().
			Msg("no listing-id provided")
	}

	if err := s.accts.SetListingInSyncGroupListingDraft(ctx, acctID, orderIndex, listingID); err != nil {
		return nil, response.Errorf("failed to set listing: %w", response.ErrorFromConstant(err))
	}

	return response.StatusOK(), nil
}

// DELETE /:acctID/inventory/sync-groups/draft/listings/{orderIndex}
func (s *accountSubrouter) deleteSyncGroupListingDraft(c *gin.Context) (response.Response, error) {
	r := c.Request
	ctx := r.Context()
	acctID := auth.GetIdentity(ctx).Account.AccountID

	orderIndex, err := getOrderIndexForSyncGroupListingDraftFromPath(c)
	if err != nil {
		return nil, err
	}

	if _, err := s.accts.DeleteSyncGroupListingDraft(ctx, acctID, orderIndex); err != nil {
		return nil, response.Errorf("failed to delete listing: %w", response.ErrorFromConstant(err))
	}

	return response.StatusOK(), nil
}

// POST /:acctID/inventory/sync-groups
func (s *accountSubrouter) saveNewSyncGroup(c *gin.Context) (response.Response, error) {
	r := c.Request
	ctx := r.Context()
	acctID := auth.GetIdentity(ctx).Account.AccountID

	if _, err := s.accts.SaveNewSyncGroup(ctx, acctID); err != nil {
		return nil, response.Errorf("failed to save new sync group: %w", response.ErrorFromConstant(err))
	}

	return response.StatusCreated(), nil
}

func getOrderIndexForSyncGroupListingDraftFromPath(c *gin.Context) (int, error) {
	orderIndexStr := c.Param("orderIndex")
	if orderIndexStr == "" {
		return 0, response.NotFound().
			Msg("no orderIndex found")
	}

	orderIndex, err := strconv.Atoi(orderIndexStr)
	if err != nil {
		return 0, response.NotFound().
			Msgf("invalid order index: %s", orderIndexStr)
	}

	return orderIndex, nil
}

// PUT /:acctID/platforms/:platform/order-index"
// this endpoint is called when dragging a platform tab in the accounts page.
func (s *accountSubrouter) setOrderOfPlatformOnAccountPage(c *gin.Context) (response.Response, error) {
	acctID := auth.GetIdentity(c).Account.AccountID

	// validate parameters

	var orderIndex int
	if v, ok := c.GetPostForm("order-index"); !ok {
		return nil, response.BadRequest().
			Msg("no order-index provided")
	} else if i, err := strconv.Atoi(v); err != nil {
		return nil, response.BadRequest().
			Msgf("order-index must be a non-negative integer: %s", v)
	} else if i < 0 {
		return nil, response.BadRequest().
			Msgf("order-index must be a non-negative integer: %s", v)
	} else {
		orderIndex = i
	}

	var platform accounts.Platform
	if v := c.Param("platform"); v == "" {
		return nil, response.BadRequest().
			Msg("no platform provided")
	} else if p, err := accounts.NewPlatform(v); err != nil {
		return nil, response.BadRequest().
			Wrap(err).
			Msgf("unrecognized platform: %v", v)
	} else {
		platform = p
	}

	// update the order

	platforms, prevIndex, err := s.accts.SetOrderOfPlatformOnAccountPage(c, acctID, platform, orderIndex)
	if err != nil {
		return nil, fmt.Errorf("failed to save record: %w", err)
	}

	// emit events on all platforms updated, so the tabs can all refresh (including their logic)

	platformEvents := make([]string, max(orderIndex, prevIndex)-min(orderIndex, prevIndex))
	if orderIndex > prevIndex {
		for i := range orderIndex - prevIndex {
			p := platforms[prevIndex+i]
			platformEvents[i] = fmt.Sprintf("accounts_%d_platforms_%s_order-index", acctID, lowerSnakeCase(p))
		}
	} else if orderIndex < prevIndex {
		for i := range prevIndex - orderIndex {
			p := platforms[orderIndex+1+i]
			platformEvents[i] = fmt.Sprintf("accounts_%d_platforms_%s_order-index", acctID, lowerSnakeCase(p))
		}
	}
	if err := s.pub.Push(c, acctID, platformEvents...); err != nil {
		s.log.Errorf("failed to publish platform order-index events: %v", err)
	}

	return response.StatusNoContent(), nil
}

func lowerSnakeCase(s accounts.Platform) string {
	return strings.ToLower(strings.Join(strings.Split(string(s), " "), "_"))
}