package handlers

import (
	"errors"
	"strconv"

	"github.com/gin-gonic/gin"

	"git.netcell-it.de/projekte/edgeguard-native/internal/handlers/response"
	"git.netcell-it.de/projekte/edgeguard-native/internal/models"
	"git.netcell-it.de/projekte/edgeguard-native/internal/services/audit"
	"git.netcell-it.de/projekte/edgeguard-native/internal/services/domains"
	"git.netcell-it.de/projekte/edgeguard-native/internal/services/routingrules"
)

type DomainsHandler struct {
	Repo     *domains.Repo
	Routing  *routingrules.Repo
	Audit    *audit.Repo
	NodeID   string
}

func NewDomainsHandler(repo *domains.Repo, routing *routingrules.Repo, a *audit.Repo, nodeID string) *DomainsHandler {
	return &DomainsHandler{Repo: repo, Routing: routing, Audit: a, NodeID: nodeID}
}

func (h *DomainsHandler) Register(rg *gin.RouterGroup) {
	g := rg.Group("/domains")
	g.GET("", h.List)
	g.POST("", h.Create)
	g.GET("/:id", h.Get)
	g.PUT("/:id", h.Update)
	g.DELETE("/:id", h.Delete)
	g.GET("/:id/routing-rules", h.ListRoutingRules)
}

func (h *DomainsHandler) List(c *gin.Context) {
	out, err := h.Repo.List(c.Request.Context())
	if err != nil {
		response.Internal(c, err)
		return
	}
	response.OK(c, gin.H{"domains": out})
}

func (h *DomainsHandler) Get(c *gin.Context) {
	id, ok := parseID(c)
	if !ok {
		return
	}
	d, err := h.Repo.Get(c.Request.Context(), id)
	if err != nil {
		if errors.Is(err, domains.ErrNotFound) {
			response.NotFound(c, err)
			return
		}
		response.Internal(c, err)
		return
	}
	response.OK(c, d)
}

func (h *DomainsHandler) Create(c *gin.Context) {
	var req models.Domain
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, err)
		return
	}
	out, err := h.Repo.Create(c.Request.Context(), req)
	if err != nil {
		response.Internal(c, err)
		return
	}
	_ = h.Audit.Log(c.Request.Context(), actorOf(c), "domain.create", req.Name, out, h.NodeID)
	response.Created(c, out)
}

func (h *DomainsHandler) Update(c *gin.Context) {
	id, ok := parseID(c)
	if !ok {
		return
	}
	var req models.Domain
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, err)
		return
	}
	out, err := h.Repo.Update(c.Request.Context(), id, req)
	if err != nil {
		if errors.Is(err, domains.ErrNotFound) {
			response.NotFound(c, err)
			return
		}
		response.Internal(c, err)
		return
	}
	_ = h.Audit.Log(c.Request.Context(), actorOf(c), "domain.update", out.Name, out, h.NodeID)
	response.OK(c, out)
}

func (h *DomainsHandler) Delete(c *gin.Context) {
	id, ok := parseID(c)
	if !ok {
		return
	}
	if err := h.Repo.Delete(c.Request.Context(), id); err != nil {
		if errors.Is(err, domains.ErrNotFound) {
			response.NotFound(c, err)
			return
		}
		response.Internal(c, err)
		return
	}
	_ = h.Audit.Log(c.Request.Context(), actorOf(c), "domain.delete",
		strconv.FormatInt(id, 10), gin.H{"id": id}, h.NodeID)
	response.NoContent(c)
}

// ListRoutingRules narrows /routing-rules to one domain — UI uses this
// for the per-domain rules tab rather than fetching the global list
// and filtering client-side.
func (h *DomainsHandler) ListRoutingRules(c *gin.Context) {
	id, ok := parseID(c)
	if !ok {
		return
	}
	out, err := h.Routing.ListForDomain(c.Request.Context(), id)
	if err != nil {
		response.Internal(c, err)
		return
	}
	response.OK(c, gin.H{"routing_rules": out})
}

// parseID parses /:id as int64 and writes a 400 on parse failure.
// Returns (0, false) and aborts when the param is malformed.
func parseID(c *gin.Context) (int64, bool) {
	id, err := strconv.ParseInt(c.Param("id"), 10, 64)
	if err != nil {
		response.BadRequest(c, errors.New("invalid id"))
		return 0, false
	}
	return id, true
}

func actorOf(c *gin.Context) string {
	if t := CurrentToken(c); t != nil {
		return t.Actor
	}
	return "unknown"
}