// Copyright 2013 The Servo Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

//! Dictionaries of key-value pairs.

pub use core_foundation_sys::dictionary::*;

use core_foundation_sys::base::{kCFAllocatorDefault, CFRelease, CFTypeRef};
use std::marker::PhantomData;
use std::mem;
use std::os::raw::c_void;
use std::ptr;

use crate::base::{CFIndexConvertible, TCFType};
use crate::base::{FromVoid, ItemRef, ToVoid};
use crate::ConcreteCFType;

// consume the type parameters with `PhantomData`
pub struct CFDictionary<K = *const c_void, V = *const c_void>(
    CFDictionaryRef,
    PhantomData<K>,
    PhantomData<V>,
);

impl<K, V> Drop for CFDictionary<K, V> {
    fn drop(&mut self) {
        unsafe { CFRelease(self.as_CFTypeRef()) }
    }
}

impl_TCFType!(CFDictionary<K, V>, CFDictionaryRef, CFDictionaryGetTypeID);
impl_CFTypeDescription!(CFDictionary<K, V>);

unsafe impl ConcreteCFType for CFDictionary<*const c_void, *const c_void> {}

impl<K, V> CFDictionary<K, V> {
    pub fn from_CFType_pairs(pairs: &[(K, V)]) -> CFDictionary<K, V>
    where
        K: TCFType,
        V: TCFType,
    {
        let (keys, values): (Vec<CFTypeRef>, Vec<CFTypeRef>) = pairs
            .iter()
            .map(|(key, value)| (key.as_CFTypeRef(), value.as_CFTypeRef()))
            .unzip();

        unsafe {
            let dictionary_ref = CFDictionaryCreate(
                kCFAllocatorDefault,
                keys.as_ptr(),
                values.as_ptr(),
                keys.len().to_CFIndex(),
                &kCFTypeDictionaryKeyCallBacks,
                &kCFTypeDictionaryValueCallBacks,
            );
            TCFType::wrap_under_create_rule(dictionary_ref)
        }
    }

    #[inline]
    pub fn to_untyped(&self) -> CFDictionary {
        unsafe { CFDictionary::wrap_under_get_rule(self.0) }
    }

    /// Returns a `CFMutableDictionary` pointing to the same underlying dictionary as this immutable one.
    /// This should only be used when the underlying dictionary is mutable.
    #[inline]
    pub unsafe fn to_mutable(&self) -> CFMutableDictionary<K, V> {
        CFMutableDictionary::wrap_under_get_rule(self.0 as CFMutableDictionaryRef)
    }

    /// Returns the same dictionary, but with the types reset to void pointers.
    /// Equal to `to_untyped`, but is faster since it does not increment the retain count.
    #[inline]
    pub fn into_untyped(self) -> CFDictionary {
        let reference = self.0;
        mem::forget(self);
        unsafe { CFDictionary::wrap_under_create_rule(reference) }
    }

    #[inline]
    pub fn len(&self) -> usize {
        unsafe { CFDictionaryGetCount(self.0) as usize }
    }

    #[inline]
    pub fn is_empty(&self) -> bool {
        self.len() == 0
    }

    #[inline]
    pub fn contains_key(&self, key: &K) -> bool
    where
        K: ToVoid<K>,
    {
        unsafe { CFDictionaryContainsKey(self.0, key.to_void()) != 0 }
    }

    #[inline]
    pub fn find<T: ToVoid<K>>(&self, key: T) -> Option<ItemRef<'_, V>>
    where
        V: FromVoid,
        K: ToVoid<K>,
    {
        unsafe {
            let mut value: *const c_void = ptr::null();
            if CFDictionaryGetValueIfPresent(self.0, key.to_void(), &mut value) != 0 {
                Some(V::from_void(value))
            } else {
                None
            }
        }
    }

    /// # Panics
    ///
    /// Panics if the key is not present in the dictionary. Use `find` to get an `Option` instead
    /// of panicking.
    #[inline]
    pub fn get<T: ToVoid<K>>(&self, key: T) -> ItemRef<'_, V>
    where
        V: FromVoid,
        K: ToVoid<K>,
    {
        let ptr = key.to_void();
        self.find(key)
            .unwrap_or_else(|| panic!("No entry found for key {:p}", ptr))
    }

    pub fn get_keys_and_values(&self) -> (Vec<*const c_void>, Vec<*const c_void>) {
        let length = self.len();
        let mut keys = Vec::with_capacity(length);
        let mut values = Vec::with_capacity(length);

        unsafe {
            CFDictionaryGetKeysAndValues(self.0, keys.as_mut_ptr(), values.as_mut_ptr());
            keys.set_len(length);
            values.set_len(length);
        }

        (keys, values)
    }
}

// consume the type parameters with `PhantomData`
pub struct CFMutableDictionary<K = *const c_void, V = *const c_void>(
    CFMutableDictionaryRef,
    PhantomData<K>,
    PhantomData<V>,
);

impl<K, V> Drop for CFMutableDictionary<K, V> {
    fn drop(&mut self) {
        unsafe { CFRelease(self.as_CFTypeRef()) }
    }
}

impl_TCFType!(CFMutableDictionary<K, V>, CFMutableDictionaryRef, CFDictionaryGetTypeID);
impl_CFTypeDescription!(CFMutableDictionary);

impl<K, V> CFMutableDictionary<K, V> {
    pub fn new() -> Self {
        Self::with_capacity(0)
    }

    pub fn with_capacity(capacity: isize) -> Self {
        unsafe {
            let dictionary_ref = CFDictionaryCreateMutable(
                kCFAllocatorDefault,
                capacity as _,
                &kCFTypeDictionaryKeyCallBacks,
                &kCFTypeDictionaryValueCallBacks,
            );
            TCFType::wrap_under_create_rule(dictionary_ref)
        }
    }

    pub fn copy_with_capacity(&self, capacity: isize) -> Self {
        unsafe {
            let dictionary_ref =
                CFDictionaryCreateMutableCopy(kCFAllocatorDefault, capacity as _, self.0);
            TCFType::wrap_under_get_rule(dictionary_ref)
        }
    }

    pub fn from_CFType_pairs(pairs: &[(K, V)]) -> CFMutableDictionary<K, V>
    where
        K: ToVoid<K>,
        V: ToVoid<V>,
    {
        let mut result = Self::with_capacity(pairs.len() as _);
        for (key, value) in pairs {
            result.add(key, value);
        }
        result
    }

    #[inline]
    pub fn to_untyped(&self) -> CFMutableDictionary {
        unsafe { CFMutableDictionary::wrap_under_get_rule(self.0) }
    }

    /// Returns the same dictionary, but with the types reset to void pointers.
    /// Equal to `to_untyped`, but is faster since it does not increment the retain count.
    #[inline]
    pub fn into_untyped(self) -> CFMutableDictionary {
        let reference = self.0;
        mem::forget(self);
        unsafe { CFMutableDictionary::wrap_under_create_rule(reference) }
    }

    /// Returns a `CFDictionary` pointing to the same underlying dictionary as this mutable one.
    #[inline]
    pub fn to_immutable(&self) -> CFDictionary<K, V> {
        unsafe { CFDictionary::wrap_under_get_rule(self.0) }
    }

    // Immutable interface

    #[inline]
    pub fn len(&self) -> usize {
        unsafe { CFDictionaryGetCount(self.0) as usize }
    }

    #[inline]
    pub fn is_empty(&self) -> bool {
        self.len() == 0
    }

    #[inline]
    pub fn contains_key(&self, key: *const c_void) -> bool {
        unsafe { CFDictionaryContainsKey(self.0, key) != 0 }
    }

    #[inline]
    pub fn find<'a>(&'a self, key: &K) -> Option<ItemRef<'a, V>>
    where
        V: FromVoid,
        K: ToVoid<K>,
    {
        unsafe {
            let mut value: *const c_void = ptr::null();
            if CFDictionaryGetValueIfPresent(self.0, key.to_void(), &mut value) != 0 {
                Some(V::from_void(value))
            } else {
                None
            }
        }
    }

    /// # Panics
    ///
    /// Panics if the key is not present in the dictionary. Use `find` to get an `Option` instead
    /// of panicking.
    #[inline]
    pub fn get<'a>(&'a self, key: &K) -> ItemRef<'a, V>
    where
        V: FromVoid,
        K: ToVoid<K>,
    {
        let ptr = key.to_void();
        self.find(key)
            .unwrap_or_else(|| panic!("No entry found for key {:p}", ptr))
    }

    pub fn get_keys_and_values(&self) -> (Vec<*const c_void>, Vec<*const c_void>) {
        let length = self.len();
        let mut keys = Vec::with_capacity(length);
        let mut values = Vec::with_capacity(length);

        unsafe {
            CFDictionaryGetKeysAndValues(self.0, keys.as_mut_ptr(), values.as_mut_ptr());
            keys.set_len(length);
            values.set_len(length);
        }

        (keys, values)
    }

    // Mutable interface

    /// Adds the key-value pair to the dictionary if no such key already exist.
    #[inline]
    pub fn add(&mut self, key: &K, value: &V)
    where
        K: ToVoid<K>,
        V: ToVoid<V>,
    {
        unsafe { CFDictionaryAddValue(self.0, key.to_void(), value.to_void()) }
    }

    /// Sets the value of the key in the dictionary.
    #[inline]
    pub fn set(&mut self, key: K, value: V)
    where
        K: ToVoid<K>,
        V: ToVoid<V>,
    {
        unsafe { CFDictionarySetValue(self.0, key.to_void(), value.to_void()) }
    }

    /// Replaces the value of the key in the dictionary.
    #[inline]
    pub fn replace(&mut self, key: K, value: V)
    where
        K: ToVoid<K>,
        V: ToVoid<V>,
    {
        unsafe { CFDictionaryReplaceValue(self.0, key.to_void(), value.to_void()) }
    }

    /// Removes the value of the key from the dictionary.
    #[inline]
    pub fn remove(&mut self, key: K)
    where
        K: ToVoid<K>,
    {
        unsafe { CFDictionaryRemoveValue(self.0, key.to_void()) }
    }

    #[inline]
    pub fn remove_all(&mut self) {
        unsafe { CFDictionaryRemoveAllValues(self.0) }
    }
}

impl<K, V> Default for CFMutableDictionary<K, V> {
    fn default() -> Self {
        Self::new()
    }
}

impl<'a, K, V> From<&'a CFDictionary<K, V>> for CFMutableDictionary<K, V> {
    /// Creates a new mutable dictionary with the key-value pairs from another dictionary.
    /// The capacity of the new mutable dictionary is not limited.
    fn from(dict: &'a CFDictionary<K, V>) -> Self {
        unsafe {
            let mut_dict_ref = CFDictionaryCreateMutableCopy(kCFAllocatorDefault, 0, dict.0);
            TCFType::wrap_under_create_rule(mut_dict_ref)
        }
    }
}

#[cfg(test)]
pub mod test {
    use super::*;
    use crate::base::{CFType, TCFType};
    use crate::boolean::CFBoolean;
    use crate::number::CFNumber;
    use crate::string::CFString;

    #[test]
    fn dictionary() {
        let bar = CFString::from_static_string("Bar");
        let baz = CFString::from_static_string("Baz");
        let boo = CFString::from_static_string("Boo");
        let foo = CFString::from_static_string("Foo");
        let tru = CFBoolean::true_value();
        let n42 = CFNumber::from(42);

        let d = CFDictionary::from_CFType_pairs(&[
            (bar.as_CFType(), boo.as_CFType()),
            (baz.as_CFType(), tru.as_CFType()),
            (foo.as_CFType(), n42.as_CFType()),
        ]);

        let (v1, v2) = d.get_keys_and_values();
        assert_eq!(
            v1,
            &[bar.as_CFTypeRef(), baz.as_CFTypeRef(), foo.as_CFTypeRef()]
        );
        assert_eq!(
            v2,
            &[boo.as_CFTypeRef(), tru.as_CFTypeRef(), n42.as_CFTypeRef()]
        );
    }

    #[test]
    fn mutable_dictionary() {
        let bar = CFString::from_static_string("Bar");
        let baz = CFString::from_static_string("Baz");
        let boo = CFString::from_static_string("Boo");
        let foo = CFString::from_static_string("Foo");
        let tru = CFBoolean::true_value();
        let n42 = CFNumber::from(42);

        let mut d = CFMutableDictionary::<CFString, CFType>::new();
        d.add(&bar, &boo.as_CFType());
        d.add(&baz, &tru.as_CFType());
        d.add(&foo, &n42.as_CFType());
        assert_eq!(d.len(), 3);

        let (v1, v2) = d.get_keys_and_values();
        assert_eq!(
            v1,
            &[bar.as_CFTypeRef(), baz.as_CFTypeRef(), foo.as_CFTypeRef()]
        );
        assert_eq!(
            v2,
            &[boo.as_CFTypeRef(), tru.as_CFTypeRef(), n42.as_CFTypeRef()]
        );

        d.remove(baz);
        assert_eq!(d.len(), 2);

        let (v1, v2) = d.get_keys_and_values();
        assert_eq!(v1, &[bar.as_CFTypeRef(), foo.as_CFTypeRef()]);
        assert_eq!(v2, &[boo.as_CFTypeRef(), n42.as_CFTypeRef()]);

        d.remove_all();
        assert_eq!(d.len(), 0)
    }

    #[test]
    fn dict_find_and_contains_key() {
        let dict = CFDictionary::from_CFType_pairs(&[(
            CFString::from_static_string("hello"),
            CFBoolean::true_value(),
        )]);
        let key = CFString::from_static_string("hello");
        let invalid_key = CFString::from_static_string("foobar");

        assert!(dict.contains_key(&key));
        assert!(!dict.contains_key(&invalid_key));

        let value = dict.find(&key).unwrap().clone();
        assert_eq!(value, CFBoolean::true_value());
        assert_eq!(dict.find(&invalid_key), None);
    }

    #[test]
    fn convert_immutable_to_mutable_dict() {
        let dict: CFDictionary<CFString, CFBoolean> = CFDictionary::from_CFType_pairs(&[(
            CFString::from_static_string("Foo"),
            CFBoolean::true_value(),
        )]);
        let mut mut_dict = CFMutableDictionary::from(&dict);
        assert_eq!(dict.retain_count(), 1);
        assert_eq!(mut_dict.retain_count(), 1);

        assert_eq!(mut_dict.len(), 1);
        assert_eq!(
            *mut_dict.get(&CFString::from_static_string("Foo")),
            CFBoolean::true_value()
        );

        mut_dict.add(
            &CFString::from_static_string("Bar"),
            &CFBoolean::false_value(),
        );
        assert_eq!(dict.len(), 1);
        assert_eq!(mut_dict.len(), 2);
    }

    #[test]
    fn mutable_dictionary_as_immutable() {
        let mut mut_dict: CFMutableDictionary<CFString, CFBoolean> = CFMutableDictionary::new();
        mut_dict.add(
            &CFString::from_static_string("Bar"),
            &CFBoolean::false_value(),
        );
        assert_eq!(mut_dict.retain_count(), 1);

        let dict = mut_dict.to_immutable();
        assert_eq!(mut_dict.retain_count(), 2);
        assert_eq!(dict.retain_count(), 2);
        assert_eq!(
            *dict.get(&CFString::from_static_string("Bar")),
            CFBoolean::false_value()
        );

        mem::drop(dict);
        assert_eq!(mut_dict.retain_count(), 1);
    }
}
