package main

import (
	"context"
	"fmt"
	"sort"

	sdkdelivery "git.novox.be/novox/mesh-sdk/go/delivery"
)

// composeTrace, when set, is told what composing a node saw and decided: the Input's credential state before it composes, and for
// each module the digest it composed against the digest already written. A test sets it to read why a composition did or did not
// move; the controller never does.
var composeTrace func(string)

// traceInput says what the node's composition will read of the pair credentials: those no row holds (would-make) and those held.
func traceInput(ctx context.Context, open *stores, node string) {
	in, err := inputFor(ctx, open)
	if err != nil {
		composeTrace(fmt.Sprintf("%s: the Input cannot be read: %v", node, err))
		return
	}
	composeTrace(fmt.Sprintf("%s: before composing, would make %+v; credentials held %+v", node, in.wouldMake, in.Credentials))
}

// traceComposed says, per composition of a node, the digest composed now against the one written.
func traceComposed(ctx context.Context, at composedPlace, node string, comps map[string]sdkdelivery.Composed) {
	keys := make([]string, 0, len(comps))
	for k := range comps {
		keys = append(keys, k)
	}
	sort.Strings(keys)
	for _, key := range keys {
		now, err := sdkdelivery.ComposedDigestOf(comps[key])
		if err != nil {
			composeTrace(fmt.Sprintf("%s: %s: no digest: %v", node, key, err))
			continue
		}
		written := "none"
		if e, err := at.digests.Get(ctx, key); err == nil {
			if v, err := sdkdelivery.DecodeComposedDigest(e.Value()); err == nil {
				written = v.Digest
			}
		}
		same := "CHANGED"
		if written == now {
			same = "same"
		}
		composeTrace(fmt.Sprintf("%s: %s: composed %.19s, written %.19s: %s", node, key, now, written, same))
	}
}