package server

import (
	"encoding/json"
	"net/http"
)

func (s *Server) handleManageRuntimeConfig(w http.ResponseWriter, r *http.Request) {
	switch r.Method {
	case http.MethodGet:
		raw := r.URL.Query().Get("raw") == "1"
		view := s.cfg.ViewRuntime(!raw)
		w.Header().Set("Content-Type", "application/json")
		json.NewEncoder(w).Encode(view)
	case http.MethodPut, http.MethodPost, http.MethodPatch:
		// read raw bytes first to allow both shapes
		bodyBytes := make([]byte, 0, 4096)
		buf := make([]byte, 4096)
		for {
			n, err := r.Body.Read(buf)
			if n > 0 {
				bodyBytes = append(bodyBytes, buf[:n]...)
			}
			if err != nil {
				break
			}
		}
		var patch map[string]string
		var wrapped struct {
			Values map[string]string `json:"values"`
		}
		if err := json.Unmarshal(bodyBytes, &wrapped); err == nil && wrapped.Values != nil && len(wrapped.Values) > 0 {
			patch = wrapped.Values
		} else {
			// flat map fallback
			_ = json.Unmarshal(bodyBytes, &patch)
		}
		if len(patch) == 0 {
			http.Error(w, "values required (send {values: {KEY: value}} or flat {KEY: value})", http.StatusBadRequest)
			return
		}
		changed, err := s.cfg.ApplyRuntimePatch(patch)
		if err != nil {
			http.Error(w, err.Error(), http.StatusBadRequest)
			return
		}
		if err := s.cfg.SaveRuntime(); err != nil {
			http.Error(w, "save: "+err.Error(), http.StatusInternalServerError)
			return
		}
		s.ApplyRuntimeConfig()
		w.Header().Set("Content-Type", "application/json")
		json.NewEncoder(w).Encode(map[string]any{"ok": true, "changed": changed, "values": s.cfg.ViewRuntime(false).Values})
	default:
		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
	}
}

func (s *Server) handleManageRuntimeConfigReset(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost && r.Method != http.MethodDelete {
		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
		return
	}
	var body struct {
		Keys []string `json:"keys"`
	}
	_ = json.NewDecoder(r.Body).Decode(&body)
	if len(body.Keys) == 0 {
		// reset all: clear overrides via ApplyRuntimePatch for each key to trigger revert
		all := s.cfg.ViewRuntime(false).Values
		patch := map[string]string{}
		for k := range all {
			patch[k] = ""
		}
		if _, err := s.cfg.ApplyRuntimePatch(patch); err != nil {
			http.Error(w, err.Error(), http.StatusBadRequest)
			return
		}
	} else {
		patch := map[string]string{}
		for _, k := range body.Keys {
			patch[k] = ""
		}
		if _, err := s.cfg.ApplyRuntimePatch(patch); err != nil {
			http.Error(w, err.Error(), http.StatusBadRequest)
			return
		}
	}
	if err := s.cfg.SaveRuntime(); err != nil {
		http.Error(w, "save: "+err.Error(), http.StatusInternalServerError)
		return
	}
	s.ApplyRuntimeConfig()
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]any{"ok": true})
}