//! The process shell: build the writers, collect `argv`, dispatch, return an
//! exit code. Every command body lives in `cli.zig`, which takes its writers as
//! parameters and is therefore testable without a process.

const std = @import("std");
const cli = @import("cli.zig");
const logging = @import("platform/logging.zig");

/// Routes every `std.log` call through the sink. Before `logging.install`
/// runs (and always under the test runner, which never installs), the sink
/// passes through to the stderr default.
pub const std_options: std.Options = .{ .logFn = logging.logFn };

// `src/tests.zig` imports this file, and this is how `cli.zig`'s tests reach
// the same runner. `src/tests.zig` is the orchestrator's file, not this
// session's.
comptime {
    _ = @import("cli.zig");
}

pub fn main(init: std.process.Init) u8 {
    // Both `File.Writer` values are self-referential and must not move, so they
    // stay in these `var` slots for the whole of `main`.
    var out_buffer: [4096]u8 = undefined;
    var err_buffer: [4096]u8 = undefined;
    var out = std.Io.File.stdout().writer(init.io, &out_buffer);
    var err = std.Io.File.stderr().writer(init.io, &err_buffer);

    const runner: cli.Runner = .{
        .io = init.io,
        .gpa = init.gpa,
        .out = &out.interface,
        .err = &err.interface,
    };

    var argv: std.ArrayList([]const u8) = .empty;
    defer argv.deinit(init.gpa);

    var args = init.minimal.args.iterate();
    _ = args.skip();
    while (args.next()) |arg| {
        argv.append(init.gpa, arg) catch return cli.exit_runtime;
    }

    const command = cli.parseArgs(argv.items) catch |e| return cli.runUsageError(runner, e);

    return switch (command) {
        .run => |paths| cli.runRun(runner, paths),
        // `true`: the probe leaves the machine, which is right for an operator
        // running `nxdns check` and wrong for a test.
        .check => |args_| cli.runCheck(runner, args_, true),
        .export_ => |args_| cli.runExport(runner, args_),
        .import_ => |args_| cli.runImport(runner, args_),
        .version => cli.runVersion(runner),
        .help => cli.runHelp(runner),
    };
}