// Copyright (c) 2017 Akos Kiss.
//
// Licensed under the BSD 3-Clause License
// <LICENSE.md or https://opensource.org/licenses/BSD-3-Clause>.
// This file may not be copied, modified, or distributed except
// according to those terms.

use std::error::Error;
use std::sync::Once;

use framework::{cb, nil, ns};
use objc::declare::ClassDecl;
use objc::runtime::{Class, Object, Protocol, Sel};
use utils::{NO_PERIPHERAL_FOUND, cbx, nsx, wait};

pub mod bm {
    use super::*;

    // BlurMacDelegate : CBCentralManagerDelegate, CBPeripheralDelegate

    const DELEGATE_PERIPHERALS_IVAR: &str = "_peripherals";

    fn delegate_class() -> &'static Class {
        trace!("delegate_class");
        static REGISTER_DELEGATE_CLASS: Once = Once::new();

        REGISTER_DELEGATE_CLASS.call_once(|| {
            let mut decl = ClassDecl::new("BlurMacDelegate", Class::get("NSObject").unwrap()).unwrap();
            decl.add_protocol(Protocol::get("CBCentralManagerDelegate").unwrap());

            decl.add_ivar::<*mut Object>(DELEGATE_PERIPHERALS_IVAR); /* NSMutableDictionary<NSString*, BlurMacPeripheralData*>* */

            unsafe {
                decl.add_method(sel!(init), delegate_init as extern fn(&mut Object, Sel) -> *mut Object);
                decl.add_method(sel!(centralManagerDidUpdateState:), delegate_centralmanagerdidupdatestate as extern fn(&mut Object, Sel, *mut Object));
                // decl.add_method(sel!(centralManager:willRestoreState:), delegate_centralmanager_willrestorestate as extern fn(&mut Object, Sel, *mut Object, *mut Object));
                decl.add_method(sel!(centralManager:didConnectPeripheral:), delegate_centralmanager_didconnectperipheral as extern fn(&mut Object, Sel, *mut Object, *mut Object));
                decl.add_method(sel!(centralManager:didDisconnectPeripheral:error:), delegate_centralmanager_diddisconnectperipheral_error as extern fn(&mut Object, Sel, *mut Object, *mut Object, *mut Object));
                // decl.add_method(sel!(centralManager:didFailToConnectPeripheral:error:), delegate_centralmanager_didfailtoconnectperipheral_error as extern fn(&mut Object, Sel, *mut Object, *mut Object, *mut Object));
                decl.add_method(sel!(centralManager:didDiscoverPeripheral:advertisementData:RSSI:), delegate_centralmanager_diddiscoverperipheral_advertisementdata_rssi as extern fn(&mut Object, Sel, *mut Object, *mut Object, *mut Object, *mut Object));

                decl.add_method(sel!(peripheral:didDiscoverServices:), delegate_peripheral_diddiscoverservices as extern fn(&mut Object, Sel, *mut Object, *mut Object));
                decl.add_method(sel!(peripheral:didDiscoverIncludedServicesForService:error:), delegate_peripheral_diddiscoverincludedservicesforservice_error as extern fn(&mut Object, Sel, *mut Object, *mut Object, *mut Object));
                decl.add_method(sel!(peripheral:didDiscoverCharacteristicsForService:error:), delegate_peripheral_diddiscovercharacteristicsforservice_error as extern fn(&mut Object, Sel, *mut Object, *mut Object, *mut Object));
                decl.add_method(sel!(peripheral:didUpdateValueForCharacteristic:error:), delegate_peripheral_didupdatevalueforcharacteristic_error as extern fn(&mut Object, Sel, *mut Object, *mut Object, *mut Object));
                decl.add_method(sel!(peripheral:didWriteValueForCharacteristic:error:), delegate_peripheral_didwritevalueforcharacteristic_error as extern fn(&mut Object, Sel, *mut Object, *mut Object, *mut Object));
                decl.add_method(sel!(peripheral:didReadRSSI:error:), delegate_peripheral_didreadrssi_error as extern fn(&mut Object, Sel, *mut Object, *mut Object, *mut Object));
            }

            decl.register();
        });

        Class::get("BlurMacDelegate").unwrap()
    }

    extern "C" fn delegate_init(delegate: &mut Object, _cmd: Sel) -> *mut Object {
        trace!("delegate_init");
        unsafe {
            delegate.set_ivar::<*mut Object>(DELEGATE_PERIPHERALS_IVAR, ns::mutabledictionary());
        }
        delegate
    }

    extern "C" fn delegate_centralmanagerdidupdatestate(
        _delegate: &mut Object,
        _cmd: Sel,
        _central: *mut Object,
    ) {
        trace!("delegate_centralmanagerdidupdatestate");
        // NOTE: this is a no-op but kept because it is a required method of the protocol
    }

    // extern fn delegate_centralmanager_willrestorestate(_delegate: &mut Object, _cmd: Sel, _central: *mut Object, _dict: *mut Object) {
    //     trace!("delegate_centralmanager_willrestorestate");
    // }

    extern "C" fn delegate_centralmanager_didconnectperipheral(
        delegate: &mut Object,
        _cmd: Sel,
        _central: *mut Object,
        peripheral: *mut Object,
    ) {
        trace!(
            "delegate_centralmanager_didconnectperipheral {}",
            cbx::peripheral_debug(peripheral)
        );
        cb::peripheral_setdelegate(peripheral, delegate);
        cb::peripheral_discoverservices(peripheral);
    }

    extern "C" fn delegate_centralmanager_diddisconnectperipheral_error(
        delegate: &mut Object,
        _cmd: Sel,
        _central: *mut Object,
        peripheral: *mut Object,
        _error: *mut Object,
    ) {
        trace!(
            "delegate_centralmanager_diddisconnectperipheral_error {}",
            cbx::peripheral_debug(peripheral)
        );
        ns::mutabledictionary_removeobjectforkey(
            delegate_peripherals(delegate),
            ns::uuid_uuidstring(cb::peer_identifier(peripheral)),
        );
    }

    // extern fn delegate_centralmanager_didfailtoconnectperipheral_error(_delegate: &mut Object, _cmd: Sel, _central: *mut Object, _peripheral: *mut Object, _error: *mut Object) {
    //     trace!("delegate_centralmanager_didfailtoconnectperipheral_error");
    // }

    extern "C" fn delegate_centralmanager_diddiscoverperipheral_advertisementdata_rssi(
        delegate: &mut Object,
        _cmd: Sel,
        _central: *mut Object,
        peripheral: *mut Object,
        adv_data: *mut Object,
        rssi: *mut Object,
    ) {
        trace!(
            "delegate_centralmanager_diddiscoverperipheral_advertisementdata_rssi {}",
            cbx::peripheral_debug(peripheral)
        );
        let peripherals = delegate_peripherals(delegate);
        let uuid_nsstring = ns::uuid_uuidstring(cb::peer_identifier(peripheral));
        let mut data = ns::dictionary_objectforkey(peripherals, uuid_nsstring);
        if data == nil {
            data = ns::mutabledictionary();
            ns::mutabledictionary_setobject_forkey(peripherals, data, uuid_nsstring);
        }

        ns::mutabledictionary_setobject_forkey(
            data,
            ns::object_copy(peripheral),
            nsx::string_from_str(PERIPHERALDATA_PERIPHERALKEY),
        );

        ns::mutabledictionary_setobject_forkey(
            data,
            rssi,
            nsx::string_from_str(PERIPHERALDATA_RSSIKEY),
        );

        let cbuuids_nsarray =
            ns::dictionary_objectforkey(adv_data, unsafe { cb::ADVERTISEMENTDATASERVICEUUIDSKEY });
        if cbuuids_nsarray != nil {
            ns::mutabledictionary_setobject_forkey(
                data,
                cbuuids_nsarray,
                nsx::string_from_str(PERIPHERALDATA_UUIDSKEY),
            );
        }

        if ns::dictionary_objectforkey(data, nsx::string_from_str(PERIPHERALDATA_EVENTSKEY)) == nil
        {
            ns::mutabledictionary_setobject_forkey(
                data,
                ns::mutabledictionary(),
                nsx::string_from_str(PERIPHERALDATA_EVENTSKEY),
            );
        }
    }

    extern "C" fn delegate_peripheral_diddiscoverservices(
        delegate: &mut Object,
        _cmd: Sel,
        peripheral: *mut Object,
        error: *mut Object,
    ) {
        trace!(
            "delegate_peripheral_diddiscoverservices {} {}",
            cbx::peripheral_debug(peripheral),
            if error != nil { "error" } else { "" }
        );
        if error == nil {
            let services = cb::peripheral_services(peripheral);
            for i in 0..ns::array_count(services) {
                let s = ns::array_objectatindex(services, i);
                cb::peripheral_discovercharacteristicsforservice(peripheral, s);
                cb::peripheral_discoverincludedservicesforservice(peripheral, s);
            }

            // Notify BluetoothDevice::get_gatt_services that discovery was successful.
            if let Ok(events) = bmx::peripheralevents(delegate, peripheral) {
                ns::mutabledictionary_setobject_forkey(
                    events,
                    wait::now(),
                    nsx::string_from_str(PERIPHERALEVENT_SERVICESDISCOVEREDKEY),
                );
            }
        }
    }

    extern "C" fn delegate_peripheral_diddiscoverincludedservicesforservice_error(
        delegate: &mut Object,
        _cmd: Sel,
        peripheral: *mut Object,
        service: *mut Object,
        error: *mut Object,
    ) {
        trace!(
            "delegate_peripheral_diddiscoverincludedservicesforservice_error {} {} {}",
            cbx::peripheral_debug(peripheral),
            cbx::service_debug(service),
            if error != nil { "error" } else { "" }
        );
        if error == nil {
            let includes = cb::service_includedservices(service);
            for i in 0..ns::array_count(includes) {
                let s = ns::array_objectatindex(includes, i);
                cb::peripheral_discovercharacteristicsforservice(peripheral, s);
            }

            // Notify BluetoothGATTService::get_includes that discovery was successful.
            if let Ok(events) = bmx::peripheralevents(delegate, peripheral) {
                ns::mutabledictionary_setobject_forkey(
                    events,
                    wait::now(),
                    bmx::includedservicesdiscoveredkey(service),
                );
            }
        }
    }

    extern "C" fn delegate_peripheral_diddiscovercharacteristicsforservice_error(
        delegate: &mut Object,
        _cmd: Sel,
        peripheral: *mut Object,
        service: *mut Object,
        error: *mut Object,
    ) {
        trace!(
            "delegate_peripheral_diddiscovercharacteristicsforservice_error {} {} {}",
            cbx::peripheral_debug(peripheral),
            cbx::service_debug(service),
            if error != nil { "error" } else { "" }
        );
        if error == nil {
            let chars = cb::service_characteristics(service);
            for i in 0..ns::array_count(chars) {
                let c = ns::array_objectatindex(chars, i);
                cb::peripheral_discoverdescriptorsforcharacteristic(peripheral, c);
            }

            // Notify BluetoothGATTService::get_gatt_characteristics that discovery was successful.
            if let Ok(events) = bmx::peripheralevents(delegate, peripheral) {
                ns::mutabledictionary_setobject_forkey(
                    events,
                    wait::now(),
                    bmx::characteristicsdiscoveredkey(service),
                );
            }
        }
    }

    extern "C" fn delegate_peripheral_didupdatevalueforcharacteristic_error(
        delegate: &mut Object,
        _cmd: Sel,
        peripheral: *mut Object,
        characteristic: *mut Object,
        error: *mut Object,
    ) {
        trace!(
            "delegate_peripheral_didupdatevalueforcharacteristic_error {} {} {}",
            cbx::peripheral_debug(peripheral),
            cbx::characteristic_debug(characteristic),
            if error != nil { "error" } else { "" }
        );
        if error == nil {
            // Notify BluetoothGATTCharacteristic::read_value that read was successful.
            if let Ok(events) = bmx::peripheralevents(delegate, peripheral) {
                ns::mutabledictionary_setobject_forkey(
                    events,
                    wait::now(),
                    bmx::valueupdatedkey(characteristic),
                );
            }
        }
    }

    extern "C" fn delegate_peripheral_didwritevalueforcharacteristic_error(
        delegate: &mut Object,
        _cmd: Sel,
        peripheral: *mut Object,
        characteristic: *mut Object,
        error: *mut Object,
    ) {
        trace!(
            "delegate_peripheral_didwritevalueforcharacteristic_error {} {} {}",
            cbx::peripheral_debug(peripheral),
            cbx::characteristic_debug(characteristic),
            if error != nil { "error" } else { "" }
        );
        if error == nil {
            // Notify BluetoothGATTCharacteristic::write_value that write was successful.
            if let Ok(events) = bmx::peripheralevents(delegate, peripheral) {
                ns::mutabledictionary_setobject_forkey(
                    events,
                    wait::now(),
                    bmx::valuewrittenkey(characteristic),
                );
            }
        }
    }

    // extern fn delegate_peripheral_didupdatenotificationstateforcharacteristic_error(_delegate: &mut Object, _cmd: Sel, _peripheral: *mut Object, _characteristic: *mut Object, _error: *mut Object) {
    //     trace!("delegate_peripheral_didupdatenotificationstateforcharacteristic_error");
    //     // TODO: this is where notifications should be handled...
    // }

    // extern fn delegate_peripheral_diddiscoverdescriptorsforcharacteristic_error(_delegate: &mut Object, _cmd: Sel, _peripheral: *mut Object, _characteristic: *mut Object, _error: *mut Object) {
    //     trace!("delegate_peripheral_diddiscoverdescriptorsforcharacteristic_error");
    // }

    // extern fn delegate_peripheral_didupdatevaluefordescriptor(_delegate: &mut Object, _cmd: Sel, _peripheral: *mut Object, _descriptor: *mut Object, _error: *mut Object) {
    //     trace!("delegate_peripheral_didupdatevaluefordescriptor");
    // }

    // extern fn delegate_peripheral_didwritevaluefordescriptor_error(_delegate: &mut Object, _cmd: Sel, _peripheral: *mut Object, _descriptor: *mut Object, _error: *mut Object) {
    //     trace!("delegate_peripheral_didwritevaluefordescriptor_error");
    // }

    extern "C" fn delegate_peripheral_didreadrssi_error(
        delegate: &mut Object,
        _cmd: Sel,
        peripheral: *mut Object,
        rssi: *mut Object,
        error: *mut Object,
    ) {
        trace!(
            "delegate_peripheral_didreadrssi_error {}",
            cbx::peripheral_debug(peripheral)
        );
        if error == nil {
            let peripherals = delegate_peripherals(delegate);
            let uuid_nsstring = ns::uuid_uuidstring(cb::peer_identifier(peripheral));
            let data = ns::dictionary_objectforkey(peripherals, uuid_nsstring);
            if data != nil {
                ns::mutabledictionary_setobject_forkey(
                    data,
                    rssi,
                    nsx::string_from_str(PERIPHERALDATA_RSSIKEY),
                );
            }
        }
    }

    pub fn delegate() -> *mut Object {
        unsafe {
            let mut delegate: *mut Object = msg_send![delegate_class(), alloc];
            delegate = msg_send![delegate, init];
            delegate
        }
    }

    pub fn delegate_peripherals(delegate: *mut Object) -> *mut Object {
        unsafe {
            let peripherals: *mut Object =
                *(*delegate).get_ivar::<*mut Object>(DELEGATE_PERIPHERALS_IVAR);
            peripherals
        }
    }

    // "BlurMacPeripheralData" = NSMutableDictionary<NSString*, id>

    pub const PERIPHERALDATA_PERIPHERALKEY: &str = "peripheral";
    pub const PERIPHERALDATA_RSSIKEY: &str = "rssi";
    pub const PERIPHERALDATA_UUIDSKEY: &str = "uuids";
    pub const PERIPHERALDATA_EVENTSKEY: &str = "events";

    pub const PERIPHERALEVENT_SERVICESDISCOVEREDKEY: &str = "services";
    pub const PERIPHERALEVENT_INCLUDEDSERVICESDISCOVEREDKEYSUFFIX: &str = ":includes";
    pub const PERIPHERALEVENT_CHARACTERISTICSDISCOVEREDKEYSUFFIX: &str = ":characteristics";
    pub const PERIPHERALEVENT_VALUEUPDATEDKEYSUFFIX: &str = ":updated";
    pub const PERIPHERALEVENT_VALUEWRITTENKEYSUFFIX: &str = ":written";
}

pub mod bmx {
    use super::*;

    pub fn peripheraldata(
        delegate: *mut Object,
        peripheral: *mut Object,
    ) -> Result<*mut Object, Box<dyn Error>> {
        let peripherals = bm::delegate_peripherals(delegate);
        let data = ns::dictionary_objectforkey(
            peripherals,
            ns::uuid_uuidstring(cb::peer_identifier(peripheral)),
        );
        if data == nil {
            warn!("peripheraldata -> NOT FOUND");
            return Err(Box::from(NO_PERIPHERAL_FOUND));
        }
        Ok(data)
    }

    pub fn peripheralevents(
        delegate: *mut Object,
        peripheral: *mut Object,
    ) -> Result<*mut Object, Box<dyn Error>> {
        let data = peripheraldata(delegate, peripheral)?;
        Ok(ns::dictionary_objectforkey(
            data,
            nsx::string_from_str(bm::PERIPHERALDATA_EVENTSKEY),
        ))
    }

    pub fn includedservicesdiscoveredkey(service: *mut Object) -> *mut Object {
        suffixedkey(
            service,
            bm::PERIPHERALEVENT_INCLUDEDSERVICESDISCOVEREDKEYSUFFIX,
        )
    }

    pub fn characteristicsdiscoveredkey(service: *mut Object) -> *mut Object {
        suffixedkey(
            service,
            bm::PERIPHERALEVENT_CHARACTERISTICSDISCOVEREDKEYSUFFIX,
        )
    }

    pub fn valueupdatedkey(characteristic: *mut Object) -> *mut Object {
        suffixedkey(characteristic, bm::PERIPHERALEVENT_VALUEUPDATEDKEYSUFFIX)
    }

    pub fn valuewrittenkey(characteristic: *mut Object) -> *mut Object {
        suffixedkey(characteristic, bm::PERIPHERALEVENT_VALUEWRITTENKEYSUFFIX)
    }

    fn suffixedkey(attribute: *mut Object, suffix: &str) -> *mut Object {
        let key = format!(
            "{}{}",
            cbx::uuid_to_canonical_uuid_string(cb::attribute_uuid(attribute)),
            suffix
        );
        nsx::string_from_str(key.as_str())
    }
}