// Package buildreads is which repositories other than a module's own its build reads source from, as its manifest
// names them (novox/hq 04-ISSUES/131): the artifacts' `context` repositories. One rule for build-agent, which says it
// in a build's outcome, and for the controller, which reads it from a done key's manifest (R4e, issue 1851): it lives
// here, not in internal/builder, so it outlasts build-agent (R4g).
package buildreads

import (
	"sort"

	"git.novox.be/novox/mesh-sdk/go/catalogue"
)

// Of is every repository other than the module's own that this build's recipes read source from, each once and in a
// fixed order, so two builds of one commit report the same thing the same way.
func Of(manifest catalogue.Manifest) []catalogue.ArtifactContext {
	if manifest.Build == nil {
		return nil
	}
	seen := map[string]bool{}
	var out []catalogue.ArtifactContext
	for _, a := range manifest.Build.Artifacts {
		if a.Context == nil || a.Context.Repository == "" {
			continue
		}
		key := a.Context.Repository + "#" + a.Context.Ref
		if seen[key] {
			continue
		}
		seen[key] = true
		out = append(out, *a.Context)
	}
	sort.Slice(out, func(i, j int) bool {
		if out[i].Repository != out[j].Repository {
			return out[i].Repository < out[j].Repository
		}
		return out[i].Ref < out[j].Ref
	})
	return out
}