const vcf = @import("src/vcf.zig")
const VCF = vcf.VCF
const allocator = std.testing.allocator;
var vcf = VCF.open("tests/test.snpeff.bcf").?; // can return null
// file and cleanup htslib memory at end of scope
defer vcf.deinit(); 
var variant = vcf.next().?; // .? syntax gets an optional result.
try stdout.print("\nvariant:{any}\n", .{variant}); // Variant(chr1:30859-30860 (G/C))
// # get the AD field
// # needs to allocate, this interface will likely change.
// # extract the FORMAT/sample AD field (allelic depth)
// # to get INFO, use get(vcf.Field.info, ...);
var fld = "AD";
var ads = std.ArrayList(i32).init(allocator)
defer ads.deinit();
try variant.get(vcf.Field.format, ads, fld);
// 4 samples * 2
try stdout.print("\nAD:{any}\n", .{ads.items}); // { 7, 0, 2, 0, 6, 0, 4, 0 }
// # genotypes:
var gts_mem = std.ArrayList(i32).init(allocator); // can re-use this for each variant
defer gts_mem.deinit();
var gts = try variant.genotypes(&gts_mem);
try stdout.print("\ngts:{any}\n", .{gts});
// # gts:[0/0/, 0/0/, 0/1/, 0/0/] (note trailing / is accurate as it's how it's stored in htslib)
// # region queries
var iter = try ivcf.query(chrom, 69269, 69270);
while (iter.next()) |v| {
    try std.testing.expect(v.start() == 69269);
}