//! The "device" library domain (library/device): what a driver author imports.
//! The flat reference data (device-abi, pci-class, acpi-ids, usb-abi, usb-ids),
//! typed MMIO access, the driver-side client libraries (driver, pci, usb,
//! block), the AML interpreter, and the data-driven device registry.

const std = @import("std");

pub fn build(b: *std.Build) void {
    const kernel = b.dependency("kernel", .{});
    const protocol = b.dependency("protocol", .{});
    const csv = b.dependency("csv", .{});

    const abi = kernel.module("abi");
    const system_call = kernel.module("system-call");
    const ipc = kernel.module("ipc");
    const time = kernel.module("time");
    // A driver finds the bus it attaches to by name — `/protocol/device-manager`,
    // `/protocol/usb-transfer`, `/protocol/block`
    // (docs/os-development/protocol-namespace.md).
    const channel = kernel.module("channel");

    // The devices sub-project's public interface (the flat wire types),
    // importable by user space, unlike the kernel-internal device model it
    // also feeds (system/kernel/device-model.zig).
    const device_abi = b.addModule("device-abi", .{
        .root_source_file = b.path("model/device-abi.zig"),
    });
    // PCI class-code decoding (class/subclass/prog-IF -> names). Pure reference
    // data, shared by kernel discovery and any user-space PCI tool.
    const pci_class = b.addModule("pci-class", .{
        .root_source_file = b.path("pci/pci-class.zig"),
    });
    // ACPI/PnP hardware-ID (_HID) names — the flat analog of pci-class.
    _ = b.addModule("acpi-ids", .{
        .root_source_file = b.path("acpi/acpi-ids.zig"),
    });
    // The AML interpreter, a build module so the ring-3 acpi service can run
    // the same parser the kernel does (docs/discovery.md). Pure Zig, no kernel
    // imports — one source, two builds.
    _ = b.addModule("aml", .{
        .root_source_file = b.path("acpi/aml/aml.zig"),
    });
    // The USB device-framework wire ABI (chapter-9 set-up packets, standard +
    // class requests, descriptors) and the USB class-code taxonomy.
    const usb_abi = b.addModule("usb-abi", .{
        .root_source_file = b.path("usb/usb-abi.zig"),
    });
    const usb_ids = b.addModule("usb-ids", .{
        .root_source_file = b.path("usb/usb-ids.zig"),
    });
    // Typed volatile MMIO register access + memory-ordering barriers, for
    // drivers on top of an mmio_map grant. Depends only on `builtin`.
    const mmio = b.addModule("mmio", .{
        .root_source_file = b.path("mmio/mmio.zig"),
    });
    // The driver author's interface: device access + the device-manager hello
    // handshake, folded together.
    const driver = b.addModule("driver", .{
        .root_source_file = b.path("driver/driver.zig"),
        .imports = &.{
            .{ .name = "abi", .module = abi },
            .{ .name = "channel", .module = channel },
            .{ .name = "device-abi", .module = device_abi },
            .{ .name = "envelope", .module = protocol.module("envelope") },
            .{ .name = "system-call", .module = system_call },
            .{ .name = "ipc", .module = ipc },
            .{ .name = "time", .module = time },
            .{ .name = "device-manager-protocol", .module = protocol.module("device-manager-protocol") },
        },
    });
    // A device driver's view of its claimed PCI function: config-space header
    // fields, BAR decode + map, capability walks (legacy + extended), MSI/MSI-X
    // programming, power state, and function-level reset — the generic PCI
    // mechanics every leaf PCI driver used to re-derive inline.
    _ = b.addModule("pci", .{
        .root_source_file = b.path("pci/pci.zig"),
        .imports = &.{
            .{ .name = "driver", .module = driver },
            .{ .name = "mmio", .module = mmio },
            .{ .name = "pci-class", .module = pci_class },
            .{ .name = "time", .module = time },
        },
    });
    // The USB class-driver transfer client: open a device on the xHCI bus and
    // drive it (control / interrupt / bulk). Re-exports usb-abi / usb-ids as
    // usb.abi / usb.ids for a single USB import.
    _ = b.addModule("usb", .{
        .root_source_file = b.path("usb/usb.zig"),
        .imports = &.{
            .{ .name = "channel", .module = channel },
            .{ .name = "envelope", .module = protocol.module("envelope") },
            .{ .name = "ipc", .module = ipc },
            .{ .name = "time", .module = time },
            .{ .name = "usb-transfer-protocol", .module = protocol.module("usb-transfer-protocol") },
            .{ .name = "usb-abi", .module = usb_abi },
            .{ .name = "usb-ids", .module = usb_ids },
        },
    });
    // The block-device client — a device type, so it lives here.
    _ = b.addModule("block", .{
        .root_source_file = b.path("block/block.zig"),
        .imports = &.{
            .{ .name = "channel", .module = channel },
            .{ .name = "envelope", .module = protocol.module("envelope") },
            .{ .name = "ipc", .module = ipc },
            .{ .name = "time", .module = time },
            .{ .name = "block-protocol", .module = protocol.module("block-protocol") },
        },
    });
    // The device registry: parse /system/configuration/devices.csv into match rules and bind a
    // reported device to a driver. Pure logic (no hardware, no syscalls), so it
    // unit-tests on the host; the device manager imports it.
    _ = b.addModule("device-registry", .{
        .root_source_file = b.path("registry/device-registry.zig"),
        .imports = &.{.{ .name = "csv", .module = csv.module("csv") }},
    });

    // Standalone `zig build test` for this domain alone; the root build keeps
    // its aggregate test step.
    const test_step = b.step("test", "Run the device library unit tests");
    for ([_][]const u8{
        "model/device-abi.zig", // wire-type sizes
        "pci/pci-class.zig", // class/subclass/prog-IF name decoding
        "acpi/acpi-ids.zig", // _HID name decoding
        "acpi/aml/aml.zig", // AML parse + interpret, incl. Notify dispatch
        "usb/usb-abi.zig", // wire sizes + bit packings + set-up packet encodings
        "usb/usb-ids.zig", // class/subclass/protocol code assignments
        "mmio/mmio.zig", // barriers assemble + registers round-trip
    }) |root| {
        const device_tests = b.addTest(.{
            .root_module = b.createModule(.{
                .root_source_file = b.path(root),
                .target = b.resolveTargetQuery(.{}),
            }),
        });
        test_step.dependOn(&b.addRunArtifact(device_tests).step);
    }
    // The registry needs its csv import wired, so it doesn't fit the loop.
    const registry_tests = b.addTest(.{
        .root_module = b.createModule(.{
            .root_source_file = b.path("registry/device-registry.zig"),
            .target = b.resolveTargetQuery(.{}),
            .imports = &.{.{ .name = "csv", .module = csv.module("csv") }},
        }),
    });
    test_step.dependOn(&b.addRunArtifact(registry_tests).step);
}
