package contactlinks

import (
	"errors"
	"net/http"

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

type Handler struct {
	service *Service
}

func NewHandler(service *Service) *Handler {
	return &Handler{service: service}
}

type contactLinkResponse struct {
	ID          uuid.UUID  `json:"id"`
	Label       string     `json:"label"`
	URL         string     `json:"url"`
	IconKey     string     `json:"icon_key"`
	IconMediaID *uuid.UUID `json:"icon_media_id"`
	Color       string     `json:"color"`
	Position    int        `json:"position"`
	IsActive    bool       `json:"is_active"`
}

func toResponse(link *ContactLink) contactLinkResponse {
	return contactLinkResponse{
		ID:          link.ID,
		Label:       link.Label,
		URL:         link.URL,
		IconKey:     link.IconKey,
		IconMediaID: link.IconMediaID,
		Color:       link.Color,
		Position:    link.Position,
		IsActive:    link.IsActive,
	}
}

func toResponseList(list []*ContactLink) []contactLinkResponse {
	resp := make([]contactLinkResponse, 0, len(list))
	for _, link := range list {
		resp = append(resp, toResponse(link))
	}
	return resp
}

// ListAdmin returns every contact link (active or not).
func (h *Handler) ListAdmin(c *gin.Context) {
	list, err := h.service.List(c.Request.Context(), false)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to list contact links"})
		return
	}
	c.JSON(http.StatusOK, gin.H{"contact_links": toResponseList(list)})
}

// ListPublic returns only active contact links, for the storefront to display.
func (h *Handler) ListPublic(c *gin.Context) {
	list, err := h.service.List(c.Request.Context(), true)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to list contact links"})
		return
	}
	c.JSON(http.StatusOK, gin.H{"contact_links": toResponseList(list)})
}

type upsertRequest struct {
	Label       string     `json:"label" binding:"required"`
	URL         string     `json:"url" binding:"required"`
	IconKey     string     `json:"icon_key"`
	IconMediaID *uuid.UUID `json:"icon_media_id"`
	Color       string     `json:"color"`
	Position    int        `json:"position"`
	IsActive    bool       `json:"is_active"`
}

func (h *Handler) Create(c *gin.Context) {
	var req upsertRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "validation error", "details": err.Error()})
		return
	}
	link, err := h.service.Create(c.Request.Context(), req.Label, req.URL, req.IconKey, req.IconMediaID, req.Color, req.Position, req.IsActive)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to create contact link"})
		return
	}
	c.JSON(http.StatusCreated, toResponse(link))
}

func (h *Handler) Update(c *gin.Context) {
	id, err := uuid.Parse(c.Param("id"))
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid id"})
		return
	}
	var req upsertRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "validation error", "details": err.Error()})
		return
	}
	link, err := h.service.Update(c.Request.Context(), id, req.Label, req.URL, req.IconKey, req.IconMediaID, req.Color, req.Position, req.IsActive)
	if err != nil {
		if errors.Is(err, ErrNotFound) {
			c.JSON(http.StatusNotFound, gin.H{"error": "contact link not found"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to update contact link"})
		return
	}
	c.JSON(http.StatusOK, toResponse(link))
}

type updatePositionRequest struct {
	Position int `json:"position"`
}

// UpdatePosition lets the admin reorder the contact link display order
// (e.g. move up/move down in the admin list) without resending the whole
// contact link payload.
func (h *Handler) UpdatePosition(c *gin.Context) {
	id, err := uuid.Parse(c.Param("id"))
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid id"})
		return
	}
	var req updatePositionRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "validation error", "details": err.Error()})
		return
	}
	link, err := h.service.UpdatePosition(c.Request.Context(), id, req.Position)
	if err != nil {
		if errors.Is(err, ErrNotFound) {
			c.JSON(http.StatusNotFound, gin.H{"error": "contact link not found"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to update position"})
		return
	}
	c.JSON(http.StatusOK, toResponse(link))
}

func (h *Handler) Delete(c *gin.Context) {
	id, err := uuid.Parse(c.Param("id"))
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid id"})
		return
	}
	if err := h.service.Delete(c.Request.Context(), id); err != nil {
		if errors.Is(err, ErrNotFound) {
			c.JSON(http.StatusNotFound, gin.H{"error": "contact link not found"})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to delete contact link"})
		return
	}
	c.Status(http.StatusNoContent)
}