package adapter

import (
	"context"
	"errors"
	"strings"

	"pve-confsync/internal/model"
	"pve-confsync/internal/pve"
)

// DatacenterID is the id of the single datacenter options object.
const DatacenterID = "datacenter"

// pveDefaultMACPrefix is injected by PVE on read when mac_prefix is unset
// (PROXMOX_OUI in pve-cluster DataCenterConfig.pm); it is not a real setting.
const pveDefaultMACPrefix = "BC:24:11"

// datacenter handles GET/PUT /cluster/options (datacenter.cfg).
// GET returns several options parsed into objects/lists, PUT expects property strings:
// the canonical form is the property string (lists joined with ';' like datacenter.cfg).
type datacenter struct{}

func (datacenter) Kind() model.Kind { return model.KindDatacenter }
func (datacenter) SDN() bool        { return false }
func (datacenter) Singleton() bool  { return true }

func (datacenter) List(ctx context.Context, c *pve.Client, _ ReadMode, _ []model.Object) ([]model.Object, []string, error) {
	var raw map[string]any
	if err := c.Get(ctx, "cluster/options", nil, &raw); err != nil {
		return nil, nil, err
	}
	// allowed-tags: read-only, computed for the calling user.
	fields := normalizeAPI(raw, "allowed-tags")
	for k, v := range fields {
		// top level lists (registered-tags) are stored as "a;b;c" in datacenter.cfg
		if l, ok := v.([]string); ok {
			fields[k] = strings.Join(l, ";")
		}
	}
	if fields["description"] == "" {
		delete(fields, "description")
	}
	if s, _ := fields["mac_prefix"].(string); strings.EqualFold(s, pveDefaultMACPrefix) {
		delete(fields, "mac_prefix")
	}
	return []model.Object{{Kind: model.KindDatacenter, ID: DatacenterID, Fields: fields}}, nil, nil
}

// Fields synchronized by default; any other option is ignored unless the
// configuration says "sync".
var dcDefaultSync = map[string]bool{
	"tag-style":       true,
	"registered-tags": true,
	"user-tag-access": true,
	"next-id":         true,
}

func (datacenter) DefaultPolicy(f string) Policy {
	if dcDefaultSync[f] {
		return Sync
	}
	return Ignore
}

// Identity of the cluster or possible secrets (http_proxy may hold credentials).
func (datacenter) Forbidden(f string) bool {
	switch f {
	case "webauthn", "u2f", "http_proxy":
		return true
	}
	return false
}

func (datacenter) Canonicalize(map[string]any) {}

func (datacenter) Required(model.Object) []string { return nil }
func (datacenter) Immutable(string) bool          { return false }

func (datacenter) Create(context.Context, *pve.Client, model.Object, string) error {
	return errors.New("datacenter options cannot be created")
}

func (datacenter) Delete(context.Context, *pve.Client, model.Object, string) error {
	return errors.New("datacenter options cannot be deleted")
}

func (datacenter) Update(ctx context.Context, c *pve.Client, _ model.Object, set map[string]any, unset []string, _ string) error {
	flat := map[string]any{}
	for k, v := range set {
		if l, ok := v.([]string); ok {
			flat[k] = strings.Join(l, ";")
		} else {
			flat[k] = v
		}
	}
	return c.Put(ctx, "cluster/options", form(flat, unset, ""), nil)
}