const std = @import("std");

pub fn build(b: *std.Build) void {
    const target = b.standardTargetOptions(.{});

    const optimize = b.standardOptimizeOption(.{});

    const root_source_file = b.path("src/tmz.zig");

    _ = b.addModule("tmz", .{ .root_source_file = root_source_file });

    const tests = b.addTest(.{
        .root_source_file = root_source_file,
        .target = target,
        .optimize = optimize,
    });

    const test_step = b.step("test", "Run unit tests");
    test_step.dependOn(&b.addRunArtifact(tests).step);

    const coverage = b.option(bool, "cover", "Generate test coverage") orelse false;

    if (coverage) {
        const coverage_output_dir = b.makeTempPath();

        const args = &[_]std.Build.Step.Run.Arg{
            .{ .bytes = b.dupe("kcov") },
            .{ .bytes = b.dupe("--collect-only") },
            .{ .bytes = b.dupe("--include-pattern=src/") },
            .{ .bytes = b.dupe("--exclude-pattern=_test") },
            .{ .bytes = b.dupe(coverage_output_dir) },
        };

        const tests_run = b.addRunArtifact(tests);
        tests_run.has_side_effects = true;

        tests_run.argv.insertSlice(0, args) catch @panic("OOM");

        const merge_step = std.Build.Step.Run.create(b, "merge kcov");
        merge_step.has_side_effects = true;
        merge_step.addArgs(&.{
            "kcov",
            "--merge",
            b.pathJoin(&.{ coverage_output_dir, "output" }),
            b.pathJoin(&.{ coverage_output_dir, "test" }),
        });
        merge_step.step.dependOn(&tests_run.step);

        const install_coverage = b.addInstallDirectory(.{
            .source_dir = .{ .cwd_relative = b.pathJoin(&.{ coverage_output_dir, "output" }) },
            .install_dir = .{ .custom = "coverage" },
            .install_subdir = "",
        });
        install_coverage.step.dependOn(&merge_step.step);
        test_step.dependOn(&install_coverage.step);
    }
}