package api

import (
	"fmt"
	"net/http"

	"code.nonshy.com/nonshy/website/pkg/config"
	"code.nonshy.com/nonshy/website/pkg/log"
	"code.nonshy.com/nonshy/website/pkg/models"
	"code.nonshy.com/nonshy/website/pkg/ratelimit"
	"code.nonshy.com/nonshy/website/pkg/session"
	"code.nonshy.com/nonshy/website/pkg/templates"
)

// User endpoint to flag other photos as explicit on their behalf.
func MarkPhotoExplicit() http.HandlerFunc {
	// Request JSON schema.
	type Request struct {
		PhotoID uint64 `json:"photoID"`
		Reason  string `json:"reason"`
		Other   string `json:"other"`
	}

	// Response JSON schema.
	type Response struct {
		OK    bool   `json:"OK"`
		Error string `json:"error,omitempty"`
	}

	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		// Get current user.
		currentUser, err := session.CurrentUser(r)
		if err != nil {
			session.FlashError(w, r, "Failed to get current user: %s", err)
			templates.Redirect(w, "/")
			return
		}

		// Parse request payload.
		var req Request
		if err := ParseJSON(r, &req); err != nil {
			SendJSON(w, http.StatusBadRequest, Response{
				Error: fmt.Sprintf("Error with request payload: %s", err),
			})
			return
		}

		// Form validation.
		if req.Reason == "" {
			SendJSON(w, http.StatusBadRequest, Response{
				Error: "Please select one of the reasons why this photo should've been marked Explicit.",
			})
			return
		}

		// Get this photo.
		photo, err := models.GetPhoto(req.PhotoID)
		if err != nil {
			SendJSON(w, http.StatusBadRequest, Response{
				Error: "That photo was not found!",
			})
			return
		}

		if !photo.Explicit {
			// Rate limit how frequently they are tagging photos, in case a user is just going around
			// and tagging EVERYTHING.
			if !currentUser.IsAdmin {
				limiter := &ratelimit.Limiter{
					Namespace:  "mark_explicit",
					ID:         currentUser.ID,
					Limit:      config.MarkExplicitRateLimit,
					Window:     config.MarkExplicitRateLimitWindow,
					CooldownAt: config.MarkExplicitRateLimitCooldownAt,
					Cooldown:   config.MarkExplicitRateLimitCooldown,
				}
				if err := limiter.Ping(); err != nil {
					SendJSON(w, http.StatusTooManyRequests, Response{
						Error: "We appreciate the enthusiasm, but you seem to be marking an unusually high number of photos!\n\n" + err.Error(),
					})
					return
				}
			}

			photo.Explicit = true
			if err := photo.Save(); err != nil {
				SendJSON(w, http.StatusBadRequest, Response{
					Error: fmt.Sprintf("Couldn't save the photo: %s", err),
				})
				return
			}

			// If a non-admin user has hit this API, log an admin report for visibility and
			// to keep a pulse on things (e.g. in case of abuse).
			if !currentUser.IsAdmin {
				fb := &models.Feedback{
					Intent:    "report",
					Subject:   "User flagged an explicit photo",
					UserID:    currentUser.ID,
					TableName: "photos",
					TableID:   photo.ID,
					Message: fmt.Sprintf(
						"A user has flagged that a photo should have been marked as Explicit.\n\n"+
							"* Reported by: %s (ID %d)\n"+
							"* Reason given: %s\n"+
							"* Elaboration (if other): %s\n\n"+
							"The photo had been immediately marked as Explicit.",
						currentUser.Username,
						currentUser.ID,
						req.Reason,
						req.Other,
					),
				}

				// Save the feedback.
				if err := models.CreateFeedback(fb); err != nil {
					log.Error("Couldn't save feedback from user updating their DOB: %s", err)
				}
			}
		}

		// Log the change.
		models.LogUpdated(&models.User{ID: photo.UserID}, currentUser, "photos", photo.ID, "Marked explicit by admin action.", []models.FieldDiff{
			models.NewFieldDiff("Explicit", false, true),
		})

		SendJSON(w, http.StatusOK, Response{
			OK: true,
		})
	})
}