package services

import (
	"strings"
	"testing"

	"github.com/breakpilot/school-service/internal/models"
)

func TestRandomToken_Hashable(t *testing.T) {
	raw, hash, err := randomToken()
	if err != nil {
		t.Fatalf("randomToken error: %v", err)
	}
	if len(raw) < 30 {
		t.Errorf("raw token suspiciously short: %d", len(raw))
	}
	if len(hash) != 64 {
		t.Errorf("sha256 hex hash must be 64 chars, got %d", len(hash))
	}
	if hashToken(raw) != hash {
		t.Errorf("hashToken(raw) must equal the hash randomToken returned")
	}
}

func TestRandomToken_NonRepeating(t *testing.T) {
	// 16 iterations, all raw tokens must differ.
	seen := map[string]struct{}{}
	for i := 0; i < 16; i++ {
		raw, _, err := randomToken()
		if err != nil {
			t.Fatalf("iter %d: %v", i, err)
		}
		if _, dup := seen[raw]; dup {
			t.Fatalf("duplicate raw token at iter %d", i)
		}
		seen[raw] = struct{}{}
	}
}

func TestHashToken_StableHexLowercase(t *testing.T) {
	h := hashToken("hello world")
	if strings.ToLower(h) != h {
		t.Errorf("hash should be lowercase hex")
	}
	if len(h) != 64 {
		t.Errorf("expected 64-char hash, got %d", len(h))
	}
}

func TestInviteParentRequest_Validation(t *testing.T) {
	tests := []struct {
		name    string
		req     models.InviteParentRequest
		wantErr bool
	}{
		{"valid", models.InviteParentRequest{
			Email: "a@b.de", ChildFirstName: "Max", ChildLastName: "Mueller",
			TTClassID: "00000000-0000-0000-0000-000000000001",
		}, false},
		{"bad email", models.InviteParentRequest{
			Email: "not-an-email", ChildFirstName: "Max", ChildLastName: "Mueller",
			TTClassID: "00000000-0000-0000-0000-000000000001",
		}, true},
		{"missing child", models.InviteParentRequest{
			Email: "a@b.de", TTClassID: "00000000-0000-0000-0000-000000000001",
		}, true},
		{"bad class uuid", models.InviteParentRequest{
			Email: "a@b.de", ChildFirstName: "Max", ChildLastName: "Mueller",
			TTClassID: "not-a-uuid",
		}, true},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			if (validate.Struct(tt.req) != nil) != tt.wantErr {
				t.Errorf("unexpected validation outcome for %s", tt.name)
			}
		})
	}
}