package domain

import "git.cin.su/m/Assistant/contracts/interaction"

type ContextProjection struct {
	Text                       string
	Source                     string
	UsedPersonalMemoryFallback bool
}

// BuildGen2Context is a read-side projection over canonical utterance history.
// PersonalMemory remains a compatibility fallback and is never written here.
func BuildGen2Context(history []interaction.HumanUtterance) ContextProjection {
	return BuildScopedGen2Context(history, "")
}

// BuildScopedGen2Context is the Gen2 retrieval boundary for household
// context. The caller supplies already-authorized history; this defensive
// filter prevents accidental cross-principal projection when a mixed source
// is passed during degraded operation.
func BuildScopedGen2Context(history []interaction.HumanUtterance, principalID string) ContextProjection {
	if principalID != "" {
		scoped := make([]interaction.HumanUtterance, 0, len(history))
		for _, item := range history {
			if item.PrincipalID == "" || string(item.PrincipalID) == principalID {
				scoped = append(scoped, item)
			}
		}
		history = scoped
	}
	text := CompilePersonalMemory(history).ContextText()
	if text != "" {
		return ContextProjection{Text: text, Source: "retrieval:interaction-utterances"}
	}
	return ContextProjection{Text: text, Source: "personal-memory-v1-fallback", UsedPersonalMemoryFallback: true}
}