const std = @import("std");

// Although this function looks imperative, note that its job is to
// declaratively construct a build graph that will be executed by an external
// runner.
pub fn build(b: *std.Build) void {
    // Standard target options allows the person running `zig build` to choose
    // what target to build for. Here we do not override the defaults, which
    // means any target is allowed, and the default is native. Other options
    // for restricting supported target set are available.
    const target = b.standardTargetOptions(.{});

    // Standard optimization options allow the person running `zig build` to select
    // between Debug, ReleaseSafe, ReleaseFast, and ReleaseSmall. Here we do not
    // set a preferred release mode, allowing the user to decide how to optimize.
    const optimize = b.standardOptimizeOption(.{});

    const teamdraft = b.addExecutable(.{
        .name = "teamdraft",
        .root_source_file = b.path("src/main.zig"),
        .target = target,
        .optimize = optimize,
    });

    const scorecorder = b.addExecutable(.{
        .name = "scorecorder",
        .root_source_file = b.path("src/scorecorder.zig"),
        .target = target,
        .optimize = optimize,
    });

    const zul = b.dependency("zul", .{ .target = target, .optimize = optimize });
    scorecorder.root_module.addImport("zul", zul.module("zul"));
    teamdraft.root_module.addImport("zul", zul.module("zul"));

    const logz = b.dependency("logz", .{ .target = target, .optimize = optimize });
    scorecorder.root_module.addImport("logz", logz.module("logz"));
    teamdraft.root_module.addImport("logz", logz.module("logz"));

    const httpz = b.dependency("httpz", .{ .target = target, .optimize = optimize });
    teamdraft.root_module.addImport("httpz", httpz.module("httpz"));

    const zmpl = b.dependency("zmpl", .{ .target = target, .optimize = optimize });
    teamdraft.root_module.addImport("zmpl", zmpl.module("zmpl"));

    const pg = b.dependency("pg", .{ .target = target, .optimize = optimize });
    teamdraft.root_module.addImport("pg", pg.module("pg"));
    scorecorder.root_module.addImport("pg", pg.module("pg"));

    // This declares intent for the executable to be installed into the
    // standard location when the user invokes the "install" step (the default
    // step when running `zig build`).
    b.installArtifact(teamdraft);
    b.installArtifact(scorecorder);

    // This *creates* a Run step in the build graph, to be executed when another
    // step is evaluated that depends on it. The next line below will establish
    // such a dependency.
    const run_cmd = b.addRunArtifact(teamdraft);

    // By making the run step depend on the install step, it will be run from the
    // installation directory rather than directly from within the cache directory.
    // This is not necessary, however, if the application depends on other installed
    // files, this ensures they will be present and in the expected location.
    run_cmd.step.dependOn(b.getInstallStep());

    // This allows the user to pass arguments to the application in the build
    // command itself, like this: `zig build run -- arg1 arg2 etc`
    if (b.args) |args| {
        run_cmd.addArgs(args);
    }

    // This creates a build step. It will be visible in the `zig build --help` menu,
    // and can be selected like this: `zig build run`
    // This will evaluate the `run` step rather than the default, which is "install".
    const run_step = b.step("run", "Run the app");
    run_step.dependOn(&run_cmd.step);

    // Creates a step for unit testing. This only builds the test executable
    // but does not run it.
    const exe_unit_tests = b.addTest(.{
        .root_source_file = b.path("src/main.zig"),
        .target = target,
        .optimize = optimize,
    });

    const run_exe_unit_tests = b.addRunArtifact(exe_unit_tests);

    // Similar to creating the run step earlier, this exposes a `test` step to
    // the `zig build --help` menu, providing a way for the user to request
    // running the unit tests.
    const test_step = b.step("test", "Run unit tests");
    test_step.dependOn(&run_exe_unit_tests.step);

    const coverage_step = b.step("coverage", "Generate a coverage report with kcov");

    const merge_step = std.Build.Step.Run.create(b, "merge coverage");
    merge_step.addArgs(&.{ "kcov", "--merge" });
    merge_step.rename_step_with_output_arg = false;
    const merged_coverage_output = merge_step.addOutputFileArg(".");

    const kcov_collect = std.Build.Step.Run.create(b, "collect coverage");
    kcov_collect.addArgs(&.{ "kcov", "--collect-only" });
    kcov_collect.addPrefixedDirectoryArg("--include-pattern=", b.path("src"));
    merge_step.addDirectoryArg(kcov_collect.addOutputFileArg(exe_unit_tests.name));
    kcov_collect.addArtifactArg(exe_unit_tests);
    kcov_collect.enableTestRunnerMode();

    const install_coverage = b.addInstallDirectory(.{
        .source_dir = merged_coverage_output,
        .install_dir = .{ .custom = "coverage" },
        .install_subdir = "",
    });
    coverage_step.dependOn(&install_coverage.step);
}