package handover

import (
	"testing"
	"time"
)

func TestBuildHappyPath(t *testing.T) {
	in := Input{
		DecisionID:    "dec-1",
		PayloadHash:   "sha256:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
		ApprovalRef:   "sha256:bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb",
		TransformRef:  "sha256:cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc",
		SinkID:        "sink:dummy-sink",
		SinkRecordRef: "file:///data/dummy-sink/dec-1.json",
		Actor:         "agent-dummy-sink",
		IssuedAt:      time.Date(2026, 1, 2, 3, 4, 5, 0, time.UTC),
	}
	stmt, err := Build(in)
	if err != nil {
		t.Fatalf("Build: %v", err)
	}
	if stmt["predicateType"] != PredicateType {
		t.Fatalf("predicateType = %v, want %v", stmt["predicateType"], PredicateType)
	}
	pred := stmt["predicate"].(map[string]any)
	if pred["decision_id"] != "dec-1" {
		t.Fatalf("predicate.decision_id = %v", pred["decision_id"])
	}
	if pred["approval_ref"] != in.ApprovalRef {
		t.Fatalf("predicate.approval_ref = %v", pred["approval_ref"])
	}
	if pred["issued_at"] != "2026-01-02T03:04:05Z" {
		t.Fatalf("predicate.issued_at = %v", pred["issued_at"])
	}
	subject := stmt["subject"].([]any)[0].(map[string]any)
	digest := subject["digest"].(map[string]any)
	wantHex := "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
	if digest["sha256"] != wantHex {
		t.Fatalf("digest.sha256 = %v, want %v", digest["sha256"], wantHex)
	}
	materials := pred["materials"].([]any)
	if len(materials) != 2 {
		t.Fatalf("materials len = %d, want 2", len(materials))
	}
}

func TestBuildRequiresFields(t *testing.T) {
	_, err := Build(Input{})
	if err == nil {
		t.Fatalf("Build empty: want err")
	}
}

func TestStripSha256Prefix(t *testing.T) {
	hex, err := StripSha256Prefix("sha256:abcd")
	if err != nil {
		t.Fatalf("StripSha256Prefix: %v", err)
	}
	if hex != "abcd" {
		t.Fatalf("hex = %q, want abcd", hex)
	}
	if _, err := StripSha256Prefix("sha512:abcd"); err == nil {
		t.Fatalf("sha512 prefix should error")
	}
	if _, err := StripSha256Prefix(""); err == nil {
		t.Fatalf("empty should error")
	}
}