package handler

import (
	"net/http"
	"strconv"

	"github.com/go-chi/chi/v5"
	"github.com/google/uuid"
	"go.uber.org/zap"

	"github.com/dbiz/cdp/data-layer/api/internal/apperr"
	"github.com/dbiz/cdp/data-layer/api/internal/middleware"
	"github.com/dbiz/cdp/data-layer/api/internal/service"
)

type ProfileHandler struct {
	svc *service.ProfileService
	log *zap.Logger
}

func NewProfileHandler(svc *service.ProfileService, log *zap.Logger) *ProfileHandler {
	return &ProfileHandler{svc: svc, log: log}
}

// Get handles GET /profiles/:id.
func (h *ProfileHandler) Get(w http.ResponseWriter, r *http.Request) {
	id, err := parseProfileID(r)
	if err != nil {
		writeError(w, err)
		return
	}
	ws := middleware.WorkspaceFromCtx(r.Context())
	p, err := h.svc.Get(r.Context(), ws, id)
	if err != nil {
		writeError(w, err)
		return
	}
	writeJSON(w, http.StatusOK, p)
}

// Timeline handles GET /profiles/:id/events.
func (h *ProfileHandler) Timeline(w http.ResponseWriter, r *http.Request) {
	id, err := parseProfileID(r)
	if err != nil {
		writeError(w, err)
		return
	}
	limit, offset := parsePagination(r, 100, 1000)

	ws := middleware.WorkspaceFromCtx(r.Context())
	res, err := h.svc.Timeline(r.Context(), ws, id, limit, offset)
	if err != nil {
		writeError(w, err)
		return
	}
	writeJSON(w, http.StatusOK, res)
}

func parseProfileID(r *http.Request) (string, error) {
	raw := chi.URLParam(r, "id")
	if raw == "" {
		return "", apperr.BadRequest("missing profile id", "id", nil)
	}
	if _, err := uuid.Parse(raw); err != nil {
		return "", apperr.BadRequest("profile id must be uuid", "id", err)
	}
	return raw, nil
}

// parsePagination reads ?limit & ?offset with bounds. Invalid values fall back
// to the defaults rather than erroring -- the endpoints are GET, not strict.
func parsePagination(r *http.Request, def, max int) (limit, offset int) {
	limit = def
	if v := r.URL.Query().Get("limit"); v != "" {
		if n, err := strconv.Atoi(v); err == nil && n > 0 && n <= max {
			limit = n
		}
	}
	if v := r.URL.Query().Get("offset"); v != "" {
		if n, err := strconv.Atoi(v); err == nil && n >= 0 {
			offset = n
		}
	}
	return
}