use crate::error::{ContextError, ErrMode, ErrorKind, FromExternalError, ParseError};
use crate::lib::std::borrow::Borrow;
use crate::lib::std::ops::Range;
use crate::stream::{Location, Stream};
use crate::stream::{Offset, StreamIsPartial};
use crate::trace::trace;
use crate::trace::trace_result;
use crate::*;

/// Implementation of [`Parser::by_ref`][Parser::by_ref]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct ByRef<'p, P> {
    p: &'p mut P,
}

impl<'p, P> ByRef<'p, P> {
    pub(crate) fn new(p: &'p mut P) -> Self {
        Self { p }
    }
}

impl<'p, I, O, E, P: Parser<I, O, E>> Parser<I, O, E> for ByRef<'p, P> {
    fn parse_next(&mut self, i: I) -> IResult<I, O, E> {
        self.p.parse_next(i)
    }
}

/// Implementation of [`Parser::map`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct Map<F, G, I, O, O2, E>
where
    F: Parser<I, O, E>,
    G: Fn(O) -> O2,
{
    parser: F,
    map: G,
    i: core::marker::PhantomData<I>,
    o: core::marker::PhantomData<O>,
    o2: core::marker::PhantomData<O2>,
    e: core::marker::PhantomData<E>,
}

impl<F, G, I, O, O2, E> Map<F, G, I, O, O2, E>
where
    F: Parser<I, O, E>,
    G: Fn(O) -> O2,
{
    pub(crate) fn new(parser: F, map: G) -> Self {
        Self {
            parser,
            map,
            i: Default::default(),
            o: Default::default(),
            o2: Default::default(),
            e: Default::default(),
        }
    }
}

impl<F, G, I, O, O2, E> Parser<I, O2, E> for Map<F, G, I, O, O2, E>
where
    F: Parser<I, O, E>,
    G: Fn(O) -> O2,
{
    fn parse_next(&mut self, i: I) -> IResult<I, O2, E> {
        match self.parser.parse_next(i) {
            Err(e) => Err(e),
            Ok((i, o)) => Ok((i, (self.map)(o))),
        }
    }
}

#[deprecated(since = "0.4.2", note = "Replaced with `TryMap`")]
pub use TryMap as MapRes;

/// Implementation of [`Parser::try_map`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct TryMap<F, G, I, O, O2, E, E2>
where
    F: Parser<I, O, E>,
    G: FnMut(O) -> Result<O2, E2>,
    I: Clone,
    E: FromExternalError<I, E2>,
{
    parser: F,
    map: G,
    i: core::marker::PhantomData<I>,
    o: core::marker::PhantomData<O>,
    o2: core::marker::PhantomData<O2>,
    e: core::marker::PhantomData<E>,
    e2: core::marker::PhantomData<E2>,
}

impl<F, G, I, O, O2, E, E2> TryMap<F, G, I, O, O2, E, E2>
where
    F: Parser<I, O, E>,
    G: FnMut(O) -> Result<O2, E2>,
    I: Clone,
    E: FromExternalError<I, E2>,
{
    pub(crate) fn new(parser: F, map: G) -> Self {
        Self {
            parser,
            map,
            i: Default::default(),
            o: Default::default(),
            o2: Default::default(),
            e: Default::default(),
            e2: Default::default(),
        }
    }
}

impl<F, G, I, O, O2, E, E2> Parser<I, O2, E> for TryMap<F, G, I, O, O2, E, E2>
where
    F: Parser<I, O, E>,
    G: FnMut(O) -> Result<O2, E2>,
    I: Clone,
    E: FromExternalError<I, E2>,
{
    fn parse_next(&mut self, input: I) -> IResult<I, O2, E> {
        let i = input.clone();
        let (input, o) = self.parser.parse_next(input)?;
        let res = match (self.map)(o) {
            Ok(o2) => Ok((input, o2)),
            Err(e) => Err(ErrMode::from_external_error(i, ErrorKind::Verify, e)),
        };
        trace_result("verify", &res);
        res
    }
}

/// Implementation of [`Parser::verify_map`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct VerifyMap<F, G, I, O, O2, E>
where
    F: Parser<I, O, E>,
    G: FnMut(O) -> Option<O2>,
    I: Clone,
    E: ParseError<I>,
{
    parser: F,
    map: G,
    i: core::marker::PhantomData<I>,
    o: core::marker::PhantomData<O>,
    o2: core::marker::PhantomData<O2>,
    e: core::marker::PhantomData<E>,
}

impl<F, G, I, O, O2, E> VerifyMap<F, G, I, O, O2, E>
where
    F: Parser<I, O, E>,
    G: FnMut(O) -> Option<O2>,
    I: Clone,
    E: ParseError<I>,
{
    pub(crate) fn new(parser: F, map: G) -> Self {
        Self {
            parser,
            map,
            i: Default::default(),
            o: Default::default(),
            o2: Default::default(),
            e: Default::default(),
        }
    }
}

impl<F, G, I, O, O2, E> Parser<I, O2, E> for VerifyMap<F, G, I, O, O2, E>
where
    F: Parser<I, O, E>,
    G: FnMut(O) -> Option<O2>,
    I: Clone,
    E: ParseError<I>,
{
    fn parse_next(&mut self, input: I) -> IResult<I, O2, E> {
        let i = input.clone();
        let (input, o) = self.parser.parse_next(input)?;
        let res = match (self.map)(o) {
            Some(o2) => Ok((input, o2)),
            None => Err(ErrMode::from_error_kind(i, ErrorKind::Verify)),
        };
        trace_result("verify", &res);
        res
    }
}

/// Implementation of [`Parser::and_then`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct AndThen<F, G, I, O, O2, E>
where
    F: Parser<I, O, E>,
    G: Parser<O, O2, E>,
    O: StreamIsPartial,
{
    outer: F,
    inner: G,
    i: core::marker::PhantomData<I>,
    o: core::marker::PhantomData<O>,
    o2: core::marker::PhantomData<O2>,
    e: core::marker::PhantomData<E>,
}

impl<F, G, I, O, O2, E> AndThen<F, G, I, O, O2, E>
where
    F: Parser<I, O, E>,
    G: Parser<O, O2, E>,
    O: StreamIsPartial,
{
    pub(crate) fn new(outer: F, inner: G) -> Self {
        Self {
            outer,
            inner,
            i: Default::default(),
            o: Default::default(),
            o2: Default::default(),
            e: Default::default(),
        }
    }
}

impl<F, G, I, O, O2, E> Parser<I, O2, E> for AndThen<F, G, I, O, O2, E>
where
    F: Parser<I, O, E>,
    G: Parser<O, O2, E>,
    O: StreamIsPartial,
{
    fn parse_next(&mut self, i: I) -> IResult<I, O2, E> {
        let (i, mut o) = self.outer.parse_next(i)?;
        let _ = o.complete();
        let (_, o2) = self.inner.parse_next(o)?;
        Ok((i, o2))
    }
}

/// Implementation of [`Parser::parse_to`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct ParseTo<P, I, O, O2, E>
where
    P: Parser<I, O, E>,
    I: Stream,
    O: crate::stream::ParseSlice<O2>,
    E: ParseError<I>,
{
    p: P,
    i: core::marker::PhantomData<I>,
    o: core::marker::PhantomData<O>,
    o2: core::marker::PhantomData<O2>,
    e: core::marker::PhantomData<E>,
}

impl<P, I, O, O2, E> ParseTo<P, I, O, O2, E>
where
    P: Parser<I, O, E>,
    I: Stream,
    O: crate::stream::ParseSlice<O2>,
    E: ParseError<I>,
{
    pub(crate) fn new(p: P) -> Self {
        Self {
            p,
            i: Default::default(),
            o: Default::default(),
            o2: Default::default(),
            e: Default::default(),
        }
    }
}

impl<P, I, O, O2, E> Parser<I, O2, E> for ParseTo<P, I, O, O2, E>
where
    P: Parser<I, O, E>,
    I: Stream,
    O: crate::stream::ParseSlice<O2>,
    E: ParseError<I>,
{
    fn parse_next(&mut self, i: I) -> IResult<I, O2, E> {
        let input = i.clone();
        let (i, o) = self.p.parse_next(i)?;

        let res = o
            .parse_slice()
            .ok_or_else(|| ErrMode::from_error_kind(input, ErrorKind::Verify));
        trace_result("verify", &res);
        Ok((i, res?))
    }
}

/// Implementation of [`Parser::flat_map`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct FlatMap<F, G, H, I, O, O2, E>
where
    F: Parser<I, O, E>,
    G: FnMut(O) -> H,
    H: Parser<I, O2, E>,
{
    f: F,
    g: G,
    h: core::marker::PhantomData<H>,
    i: core::marker::PhantomData<I>,
    o: core::marker::PhantomData<O>,
    o2: core::marker::PhantomData<O2>,
    e: core::marker::PhantomData<E>,
}

impl<F, G, H, I, O, O2, E> FlatMap<F, G, H, I, O, O2, E>
where
    F: Parser<I, O, E>,
    G: FnMut(O) -> H,
    H: Parser<I, O2, E>,
{
    pub(crate) fn new(f: F, g: G) -> Self {
        Self {
            f,
            g,
            h: Default::default(),
            i: Default::default(),
            o: Default::default(),
            o2: Default::default(),
            e: Default::default(),
        }
    }
}

impl<F, G, H, I, O, O2, E> Parser<I, O2, E> for FlatMap<F, G, H, I, O, O2, E>
where
    F: Parser<I, O, E>,
    G: FnMut(O) -> H,
    H: Parser<I, O2, E>,
{
    fn parse_next(&mut self, i: I) -> IResult<I, O2, E> {
        let (i, o) = self.f.parse_next(i)?;
        (self.g)(o).parse_next(i)
    }
}

/// Implementation of [`Parser::complete_err`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct CompleteErr<F> {
    f: F,
}

impl<F> CompleteErr<F> {
    pub(crate) fn new(f: F) -> Self {
        Self { f }
    }
}

impl<F, I, O, E> Parser<I, O, E> for CompleteErr<F>
where
    I: Stream,
    F: Parser<I, O, E>,
    E: ParseError<I>,
{
    fn parse_next(&mut self, input: I) -> IResult<I, O, E> {
        trace("complete_err", |input: I| {
            let i = input.clone();
            match (self.f).parse_next(input) {
                Err(ErrMode::Incomplete(_)) => {
                    Err(ErrMode::from_error_kind(i, ErrorKind::Complete))
                }
                rest => rest,
            }
        })
        .parse_next(input)
    }
}

/// Implementation of [`Parser::verify`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct Verify<F, G, I, O, O2, E>
where
    F: Parser<I, O, E>,
    G: Fn(&O2) -> bool,
    I: Clone,
    O: Borrow<O2>,
    O2: ?Sized,
    E: ParseError<I>,
{
    parser: F,
    filter: G,
    i: core::marker::PhantomData<I>,
    o: core::marker::PhantomData<O>,
    o2: core::marker::PhantomData<O2>,
    e: core::marker::PhantomData<E>,
}

impl<F, G, I, O, O2, E> Verify<F, G, I, O, O2, E>
where
    F: Parser<I, O, E>,
    G: Fn(&O2) -> bool,
    I: Clone,
    O: Borrow<O2>,
    O2: ?Sized,
    E: ParseError<I>,
{
    pub(crate) fn new(parser: F, filter: G) -> Self {
        Self {
            parser,
            filter,
            i: Default::default(),
            o: Default::default(),
            o2: Default::default(),
            e: Default::default(),
        }
    }
}

impl<F, G, I, O, O2, E> Parser<I, O, E> for Verify<F, G, I, O, O2, E>
where
    F: Parser<I, O, E>,
    G: Fn(&O2) -> bool,
    I: Clone,
    O: Borrow<O2>,
    O2: ?Sized,
    E: ParseError<I>,
{
    fn parse_next(&mut self, input: I) -> IResult<I, O, E> {
        let i = input.clone();
        let (input, o) = self.parser.parse_next(input)?;

        let res = if (self.filter)(o.borrow()) {
            Ok((input, o))
        } else {
            Err(ErrMode::from_error_kind(i, ErrorKind::Verify))
        };
        trace_result("verify", &res);
        res
    }
}

/// Implementation of [`Parser::value`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct Value<F, I, O, O2, E>
where
    F: Parser<I, O, E>,
    O2: Clone,
{
    parser: F,
    val: O2,
    i: core::marker::PhantomData<I>,
    o: core::marker::PhantomData<O>,
    e: core::marker::PhantomData<E>,
}

impl<F, I, O, O2, E> Value<F, I, O, O2, E>
where
    F: Parser<I, O, E>,
    O2: Clone,
{
    pub(crate) fn new(parser: F, val: O2) -> Self {
        Self {
            parser,
            val,
            i: Default::default(),
            o: Default::default(),
            e: Default::default(),
        }
    }
}

impl<F, I, O, O2, E> Parser<I, O2, E> for Value<F, I, O, O2, E>
where
    F: Parser<I, O, E>,
    O2: Clone,
{
    fn parse_next(&mut self, input: I) -> IResult<I, O2, E> {
        (self.parser)
            .parse_next(input)
            .map(|(i, _)| (i, self.val.clone()))
    }
}

/// Implementation of [`Parser::void`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct Void<F, I, O, E>
where
    F: Parser<I, O, E>,
{
    parser: F,
    i: core::marker::PhantomData<I>,
    o: core::marker::PhantomData<O>,
    e: core::marker::PhantomData<E>,
}

impl<F, I, O, E> Void<F, I, O, E>
where
    F: Parser<I, O, E>,
{
    pub(crate) fn new(parser: F) -> Self {
        Self {
            parser,
            i: Default::default(),
            o: Default::default(),
            e: Default::default(),
        }
    }
}

impl<F, I, O, E> Parser<I, (), E> for Void<F, I, O, E>
where
    F: Parser<I, O, E>,
{
    fn parse_next(&mut self, input: I) -> IResult<I, (), E> {
        (self.parser).parse_next(input).map(|(i, _)| (i, ()))
    }
}

/// Implementation of [`Parser::recognize`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct Recognize<F, I, O, E>
where
    F: Parser<I, O, E>,
    I: Stream + Offset,
{
    parser: F,
    i: core::marker::PhantomData<I>,
    o: core::marker::PhantomData<O>,
    e: core::marker::PhantomData<E>,
}

impl<F, I, O, E> Recognize<F, I, O, E>
where
    F: Parser<I, O, E>,
    I: Stream + Offset,
{
    pub(crate) fn new(parser: F) -> Self {
        Self {
            parser,
            i: Default::default(),
            o: Default::default(),
            e: Default::default(),
        }
    }
}

impl<I, O, E, F> Parser<I, <I as Stream>::Slice, E> for Recognize<F, I, O, E>
where
    F: Parser<I, O, E>,
    I: Stream + Offset,
{
    fn parse_next(&mut self, input: I) -> IResult<I, <I as Stream>::Slice, E> {
        let i = input.clone();
        match (self.parser).parse_next(i) {
            Ok((i, _)) => {
                let offset = input.offset_to(&i);
                Ok(input.next_slice(offset))
            }
            Err(e) => Err(e),
        }
    }
}

/// Implementation of [`Parser::with_recognized`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct WithRecognized<F, I, O, E>
where
    F: Parser<I, O, E>,
    I: Stream + Offset,
{
    parser: F,
    i: core::marker::PhantomData<I>,
    o: core::marker::PhantomData<O>,
    e: core::marker::PhantomData<E>,
}

impl<F, I, O, E> WithRecognized<F, I, O, E>
where
    F: Parser<I, O, E>,
    I: Stream + Offset,
{
    pub(crate) fn new(parser: F) -> Self {
        Self {
            parser,
            i: Default::default(),
            o: Default::default(),
            e: Default::default(),
        }
    }
}

impl<F, I, O, E> Parser<I, (O, <I as Stream>::Slice), E> for WithRecognized<F, I, O, E>
where
    F: Parser<I, O, E>,
    I: Stream + Offset,
{
    fn parse_next(&mut self, input: I) -> IResult<I, (O, <I as Stream>::Slice), E> {
        let i = input.clone();
        match (self.parser).parse_next(i) {
            Ok((remaining, result)) => {
                let offset = input.offset_to(&remaining);
                let (remaining, recognized) = input.next_slice(offset);
                Ok((remaining, (result, recognized)))
            }
            Err(e) => Err(e),
        }
    }
}

/// Implementation of [`Parser::span`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct Span<F, I, O, E>
where
    F: Parser<I, O, E>,
    I: Clone + Location,
{
    parser: F,
    i: core::marker::PhantomData<I>,
    o: core::marker::PhantomData<O>,
    e: core::marker::PhantomData<E>,
}

impl<F, I, O, E> Span<F, I, O, E>
where
    F: Parser<I, O, E>,
    I: Clone + Location,
{
    pub(crate) fn new(parser: F) -> Self {
        Self {
            parser,
            i: Default::default(),
            o: Default::default(),
            e: Default::default(),
        }
    }
}

impl<I, O, E, F> Parser<I, Range<usize>, E> for Span<F, I, O, E>
where
    F: Parser<I, O, E>,
    I: Clone + Location,
{
    fn parse_next(&mut self, input: I) -> IResult<I, Range<usize>, E> {
        let start = input.location();
        self.parser.parse_next(input).map(move |(remaining, _)| {
            let end = remaining.location();
            (remaining, (start..end))
        })
    }
}

/// Implementation of [`Parser::with_span`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct WithSpan<F, I, O, E>
where
    F: Parser<I, O, E>,
    I: Clone + Location,
{
    parser: F,
    i: core::marker::PhantomData<I>,
    o: core::marker::PhantomData<O>,
    e: core::marker::PhantomData<E>,
}

impl<F, I, O, E> WithSpan<F, I, O, E>
where
    F: Parser<I, O, E>,
    I: Clone + Location,
{
    pub(crate) fn new(parser: F) -> Self {
        Self {
            parser,
            i: Default::default(),
            o: Default::default(),
            e: Default::default(),
        }
    }
}

impl<F, I, O, E> Parser<I, (O, Range<usize>), E> for WithSpan<F, I, O, E>
where
    F: Parser<I, O, E>,
    I: Clone + Location,
{
    fn parse_next(&mut self, input: I) -> IResult<I, (O, Range<usize>), E> {
        let start = input.location();
        self.parser
            .parse_next(input)
            .map(move |(remaining, output)| {
                let end = remaining.location();
                (remaining, (output, (start..end)))
            })
    }
}

/// Implementation of [`Parser::output_into`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct OutputInto<F, I, O, O2, E>
where
    F: Parser<I, O, E>,
    O: Into<O2>,
{
    parser: F,
    i: core::marker::PhantomData<I>,
    o: core::marker::PhantomData<O>,
    o2: core::marker::PhantomData<O2>,
    e: core::marker::PhantomData<E>,
}

impl<F, I, O, O2, E> OutputInto<F, I, O, O2, E>
where
    F: Parser<I, O, E>,
    O: Into<O2>,
{
    pub(crate) fn new(parser: F) -> Self {
        Self {
            parser,
            i: Default::default(),
            o: Default::default(),
            o2: Default::default(),
            e: Default::default(),
        }
    }
}

impl<F, I, O, O2, E> Parser<I, O2, E> for OutputInto<F, I, O, O2, E>
where
    F: Parser<I, O, E>,
    O: Into<O2>,
{
    fn parse_next(&mut self, i: I) -> IResult<I, O2, E> {
        match self.parser.parse_next(i) {
            Ok((i, o)) => Ok((i, o.into())),
            Err(err) => Err(err),
        }
    }
}

/// Implementation of [`Parser::err_into`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct ErrInto<F, I, O, E, E2>
where
    F: Parser<I, O, E>,
    E: Into<E2>,
{
    parser: F,
    i: core::marker::PhantomData<I>,
    o: core::marker::PhantomData<O>,
    e: core::marker::PhantomData<E>,
    e2: core::marker::PhantomData<E2>,
}

impl<F, I, O, E, E2> ErrInto<F, I, O, E, E2>
where
    F: Parser<I, O, E>,
    E: Into<E2>,
{
    pub(crate) fn new(parser: F) -> Self {
        Self {
            parser,
            i: Default::default(),
            o: Default::default(),
            e: Default::default(),
            e2: Default::default(),
        }
    }
}

impl<F, I, O, E, E2> Parser<I, O, E2> for ErrInto<F, I, O, E, E2>
where
    F: Parser<I, O, E>,
    E: Into<E2>,
{
    fn parse_next(&mut self, i: I) -> IResult<I, O, E2> {
        match self.parser.parse_next(i) {
            Ok(ok) => Ok(ok),
            Err(ErrMode::Backtrack(e)) => Err(ErrMode::Backtrack(e.into())),
            Err(ErrMode::Cut(e)) => Err(ErrMode::Cut(e.into())),
            Err(ErrMode::Incomplete(e)) => Err(ErrMode::Incomplete(e)),
        }
    }
}

/// Implementation of [`Parser::context`]
#[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
pub struct Context<F, I, O, E, C>
where
    F: Parser<I, O, E>,
    I: Stream,
    E: ContextError<I, C>,
    C: Clone + crate::lib::std::fmt::Debug,
{
    parser: F,
    context: C,
    i: core::marker::PhantomData<I>,
    o: core::marker::PhantomData<O>,
    e: core::marker::PhantomData<E>,
}

impl<F, I, O, E, C> Context<F, I, O, E, C>
where
    F: Parser<I, O, E>,
    I: Stream,
    E: ContextError<I, C>,
    C: Clone + crate::lib::std::fmt::Debug,
{
    pub(crate) fn new(parser: F, context: C) -> Self {
        Self {
            parser,
            context,
            i: Default::default(),
            o: Default::default(),
            e: Default::default(),
        }
    }
}

impl<F, I, O, E, C> Parser<I, O, E> for Context<F, I, O, E, C>
where
    F: Parser<I, O, E>,
    I: Stream,
    E: ContextError<I, C>,
    C: Clone + crate::lib::std::fmt::Debug,
{
    fn parse_next(&mut self, i: I) -> IResult<I, O, E> {
        #[cfg(feature = "debug")]
        let name = format!("context={:?}", self.context);
        #[cfg(not(feature = "debug"))]
        let name = "context";
        trace(name, move |i: I| {
            (self.parser)
                .parse_next(i.clone())
                .map_err(|err| err.map(|err| err.add_context(i, self.context.clone())))
        })
        .parse_next(i)
    }
}