package handlers

import (
	"context"
	"errors"
	"log/slog"

	"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"
	ntpsvc "git.netcell-it.de/projekte/edgeguard-native/internal/services/ntp"
)

type NTPHandler struct {
	Repo     *ntpsvc.Repo
	Audit    *audit.Repo
	NodeID   string
	Reloader func(ctx context.Context) error
}

func NewNTPHandler(repo *ntpsvc.Repo, a *audit.Repo, nodeID string, reloader func(context.Context) error) *NTPHandler {
	return &NTPHandler{Repo: repo, Audit: a, NodeID: nodeID, Reloader: reloader}
}

func (h *NTPHandler) reload(ctx context.Context, op string) {
	if h.Reloader == nil {
		return
	}
	if err := h.Reloader(ctx); err != nil {
		slog.Warn("chrony: reload after mutation failed", "op", op, "error", err)
	}
}

func (h *NTPHandler) Register(rg *gin.RouterGroup) {
	g := rg.Group("/ntp")
	g.GET("/settings", h.GetSettings)
	g.PUT("/settings", h.UpdateSettings)

	p := g.Group("/pools")
	p.GET("", h.ListPools)
	p.POST("", h.CreatePool)
	p.GET("/:id", h.GetPool)
	p.PUT("/:id", h.UpdatePool)
	p.DELETE("/:id", h.DeletePool)
}

func (h *NTPHandler) GetSettings(c *gin.Context) {
	s, err := h.Repo.GetSettings(c.Request.Context())
	if err != nil {
		response.Internal(c, err)
		return
	}
	response.OK(c, s)
}

func (h *NTPHandler) UpdateSettings(c *gin.Context) {
	var req models.NTPSettings
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, err)
		return
	}
	out, err := h.Repo.UpdateSettings(c.Request.Context(), req)
	if err != nil {
		response.Internal(c, err)
		return
	}
	_ = h.Audit.Log(c.Request.Context(), actorOf(c), "ntp.settings.update", "settings", out, h.NodeID)
	response.OK(c, out)
	h.reload(c.Request.Context(), "settings.update")
}

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

func (h *NTPHandler) GetPool(c *gin.Context) {
	id, ok := parseID(c)
	if !ok {
		return
	}
	p, err := h.Repo.GetPool(c.Request.Context(), id)
	if err != nil {
		if errors.Is(err, ntpsvc.ErrPoolNotFound) {
			response.NotFound(c, err)
			return
		}
		response.Internal(c, err)
		return
	}
	response.OK(c, p)
}

func (h *NTPHandler) CreatePool(c *gin.Context) {
	var req models.NTPPool
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, err)
		return
	}
	if err := validateNTPPool(&req); err != nil {
		response.BadRequest(c, err)
		return
	}
	out, err := h.Repo.CreatePool(c.Request.Context(), req)
	if err != nil {
		response.Internal(c, err)
		return
	}
	_ = h.Audit.Log(c.Request.Context(), actorOf(c), "ntp.pool.create", out.Address, out, h.NodeID)
	response.Created(c, out)
	h.reload(c.Request.Context(), "pool.create")
}

func (h *NTPHandler) UpdatePool(c *gin.Context) {
	id, ok := parseID(c)
	if !ok {
		return
	}
	var req models.NTPPool
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, err)
		return
	}
	if err := validateNTPPool(&req); err != nil {
		response.BadRequest(c, err)
		return
	}
	out, err := h.Repo.UpdatePool(c.Request.Context(), id, req)
	if err != nil {
		if errors.Is(err, ntpsvc.ErrPoolNotFound) {
			response.NotFound(c, err)
			return
		}
		response.Internal(c, err)
		return
	}
	_ = h.Audit.Log(c.Request.Context(), actorOf(c), "ntp.pool.update", out.Address, out, h.NodeID)
	response.OK(c, out)
	h.reload(c.Request.Context(), "pool.update")
}

func (h *NTPHandler) DeletePool(c *gin.Context) {
	id, ok := parseID(c)
	if !ok {
		return
	}
	if err := h.Repo.DeletePool(c.Request.Context(), id); err != nil {
		if errors.Is(err, ntpsvc.ErrPoolNotFound) {
			response.NotFound(c, err)
			return
		}
		response.Internal(c, err)
		return
	}
	response.NoContent(c)
	h.reload(c.Request.Context(), "pool.delete")
}

func validateNTPPool(p *models.NTPPool) error {
	if p.Address == "" {
		return errors.New("address required")
	}
	switch p.Kind {
	case "pool", "server":
	default:
		return errors.New("kind must be 'pool' or 'server'")
	}
	return nil
}