const std = @import("std");
const input = @import("input.zig");
const protocol = @import("protocol.zig");
const replay = @import("replay.zig");
const session = @import("session.zig");
const socket = @import("socket.zig");
const tui = @import("tui.zig");

pub const version = "0.1.0-dev";

const help_text =
    \\mim - mobile-first terminal code editor for SSH sessions
    \\
    \\Usage:
    \\  mim [--help]
    \\  mim [--version]
    \\  mim --mimctl <socket|-> <request...>
    \\
    \\This early build exposes the canonical smoke path and a minimal local
    \\session-control client for trusted tools.
    \\
;

const Command = union(enum) {
    help,
    version,
    smoke,
    unknown: []const u8,
};

fn parseArgs(args: []const []const u8) Command {
    if (args.len <= 1) return .smoke;

    const arg = args[1];
    if (std.mem.eql(u8, arg, "--help") or std.mem.eql(u8, arg, "-h")) return .help;
    if (std.mem.eql(u8, arg, "--version")) return .version;
    return .{ .unknown = arg };
}

fn versionText() []const u8 {
    return "mim " ++ version ++ "\n";
}

pub fn main(init: std.process.Init) !u8 {
    var debug_allocator = std.heap.DebugAllocator(.{}){};
    defer _ = debug_allocator.deinit();
    const allocator = debug_allocator.allocator();

    var args = std.process.Args.Iterator.init(init.minimal.args);
    _ = args.skip();

    const stdout = std.Io.File.stdout();
    const stderr = std.Io.File.stderr();

    const first_arg = args.next();
    if (first_arg) |arg| {
        if (std.mem.eql(u8, arg, "--mimctl")) {
            const socket_path = args.next() orelse {
                try stderr.writeStreamingAll(init.io, "mim: --mimctl requires a socket path\n");
                return 64;
            };
            const line = try collectRemainingArgs(allocator, &args);
            defer allocator.free(line);
            if (line.len == 0) {
                try stderr.writeStreamingAll(init.io, "mim: --mimctl requires a request\n");
                return 64;
            }
            const resolved_socket_path = if (std.mem.eql(u8, socket_path, "-"))
                std.process.Environ.getAlloc(init.minimal.environ, allocator, socket.socket_env_name) catch {
                    try stderr.writeStreamingAll(init.io, "mim: MIM_SOCKET is not set\n");
                    return 69;
                }
            else
                try allocator.dupe(u8, socket_path);
            defer allocator.free(resolved_socket_path);

            const response = socket.request(allocator, resolved_socket_path, line) catch {
                try stderr.writeStreamingAll(init.io, "mim: mimctl request failed\n");
                return 69;
            };
            defer allocator.free(response);
            try stdout.writeStreamingAll(init.io, response);
            return 0;
        }
    }

    const command = if (first_arg) |arg|
        parseArgs(&.{ "mim", arg })
    else
        parseArgs(&.{"mim"});

    switch (command) {
        .help => try stdout.writeStreamingAll(init.io, help_text),
        .version => try stdout.writeStreamingAll(init.io, versionText()),
        .smoke => try stdout.writeStreamingAll(init.io, help_text),
        .unknown => |arg| {
            try stderr.writeStreamingAll(init.io, "mim: unknown argument '");
            try stderr.writeStreamingAll(init.io, arg);
            try stderr.writeStreamingAll(init.io, "'\nTry 'mim --help'.\n");
            return 64;
        },
    }

    return 0;
}

fn collectRemainingArgs(allocator: std.mem.Allocator, args: *std.process.Args.Iterator) ![]u8 {
    var line = std.ArrayList(u8).empty;
    errdefer line.deinit(allocator);
    var first = true;
    while (args.next()) |arg| {
        if (!first) try line.append(allocator, ' ');
        try line.appendSlice(allocator, arg);
        first = false;
    }
    return line.toOwnedSlice(allocator);
}

test {
    _ = input;
    _ = protocol;
    _ = replay;
    _ = session;
    _ = socket;
    _ = tui;
}

test "regular: help text names the binary and smoke boundary" {
    try std.testing.expect(std.mem.indexOf(u8, help_text, "mim - mobile-first terminal code editor") != null);
    try std.testing.expect(std.mem.indexOf(u8, help_text, "canonical smoke path") != null);
}

test "regular: version output is stable enough for smoke checks" {
    try std.testing.expectEqualStrings("mim 0.1.0-dev\n", versionText());
}

test "adversarial: unknown arguments are rejected instead of ignored" {
    const argv = [_][]const u8{ "mim", "--definitely-not-supported" };
    const parsed = parseArgs(&argv);
    switch (parsed) {
        .unknown => |arg| try std.testing.expectEqualStrings("--definitely-not-supported", arg),
        else => return error.ExpectedUnknownArgument,
    }
}

test "adversarial: extra positional arguments are not treated as files yet" {
    const argv = [_][]const u8{ "mim", "some-file.zig" };
    const parsed = parseArgs(&argv);
    switch (parsed) {
        .unknown => |arg| try std.testing.expectEqualStrings("some-file.zig", arg),
        else => return error.ExpectedUnknownArgument,
    }
}