/*
 * Copyright (c) 2020-2023, Stalwart Labs Ltd.
 *
 * This file is part of the Stalwart Sieve Interpreter.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Affero General Public License for more details.
 * in the LICENSE file at the top-level directory of this distribution.
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * You can be released from the requirements of the AGPLv3 license by
 * purchasing a commercial license. Please contact licensing@stalw.art
 * for more details.
*/

use phf::phf_map;
use serde::{Deserialize, Serialize};

use crate::sieve::{
    compiler::{
        grammar::{instruction::CompilerState, Capability, Comparator},
        lexer::{word::Word, Token},
        CompileError, ErrorType, Value,
    },
    Envelope,
};

use crate::sieve::compiler::grammar::{test::Test, AddressPart, MatchType};

use std::convert::TryFrom;

#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub(crate) struct TestEnvelope {
    pub envelope_list: Vec<Envelope>,
    pub key_list: Vec<Value>,
    pub address_part: AddressPart,
    pub match_type: MatchType,
    pub comparator: Comparator,
    pub zone: Option<i64>,
    pub is_not: bool,
}

impl<'x> CompilerState<'x> {
    pub(crate) fn parse_test_envelope(&mut self) -> Result<Test, CompileError> {
        let mut address_part = AddressPart::All;
        let mut match_type = MatchType::Is;
        let mut comparator = Comparator::AsciiCaseMap;
        let mut envelope_list = None;
        let mut key_list;
        let mut zone = None;

        loop {
            let mut token_info = self.tokens.unwrap_next()?;
            match token_info.token {
                Token::Tag(
                    word @ (Word::LocalPart | Word::Domain | Word::All | Word::User | Word::Detail),
                ) => {
                    self.validate_argument(
                        1,
                        if matches!(word, Word::User | Word::Detail) {
                            Capability::SubAddress.into()
                        } else {
                            None
                        },
                        token_info.line_num,
                        token_info.line_pos,
                    )?;
                    address_part = word.into();
                }
                Token::Tag(
                    word @ (Word::Is
                    | Word::Contains
                    | Word::Matches
                    | Word::Value
                    | Word::Count
                    | Word::Regex
                    | Word::List),
                ) => {
                    self.validate_argument(
                        2,
                        match word {
                            Word::Value | Word::Count => Capability::Relational.into(),
                            Word::Regex => Capability::Regex.into(),
                            Word::List => Capability::ExtLists.into(),
                            _ => None,
                        },
                        token_info.line_num,
                        token_info.line_pos,
                    )?;

                    match_type = self.parse_match_type(word)?;
                }
                Token::Tag(Word::Comparator) => {
                    self.validate_argument(3, None, token_info.line_num, token_info.line_pos)?;
                    comparator = self.parse_comparator()?;
                }
                Token::Tag(Word::Zone) => {
                    self.validate_argument(
                        4,
                        Capability::EnvelopeDeliverBy.into(),
                        token_info.line_num,
                        token_info.line_pos,
                    )?;
                    zone = self.parse_timezone()?.into();
                }
                _ => {
                    if envelope_list.is_none() {
                        let mut envelopes = Vec::new();
                        let line_num = token_info.line_num;
                        let line_pos = token_info.line_pos;

                        match token_info.token {
                            Token::StringConstant(s) => match Envelope::try_from(s.into_string()) {
                                Ok(envelope) => {
                                    envelopes.push(envelope);
                                }
                                Err(invalid) => {
                                    token_info.token = Token::Comma;
                                    return Err(
                                        token_info.custom(ErrorType::InvalidEnvelope(invalid))
                                    );
                                }
                            },
                            Token::BracketOpen => loop {
                                let mut token_info = self.tokens.unwrap_next()?;
                                match token_info.token {
                                    Token::StringConstant(s) => {
                                        match Envelope::try_from(s.into_string()) {
                                            Ok(envelope) => {
                                                if !envelopes.contains(&envelope) {
                                                    envelopes.push(envelope);
                                                }
                                            }
                                            Err(invalid) => {
                                                token_info.token = Token::Comma;
                                                return Err(token_info
                                                    .custom(ErrorType::InvalidEnvelope(invalid)));
                                            }
                                        }
                                    }
                                    Token::Comma => (),
                                    Token::BracketClose if !envelopes.is_empty() => break,
                                    _ => return Err(token_info.expected("constant string")),
                                }
                            },
                            _ => return Err(token_info.expected("constant string")),
                        }

                        for envelope in &envelopes {
                            match envelope {
                                Envelope::ByTimeAbsolute
                                | Envelope::ByTimeRelative
                                | Envelope::ByMode
                                | Envelope::ByTrace => {
                                    self.validate_argument(
                                        0,
                                        Capability::EnvelopeDeliverBy.into(),
                                        line_num,
                                        line_pos,
                                    )?;
                                }

                                Envelope::Notify
                                | Envelope::Orcpt
                                | Envelope::Ret
                                | Envelope::Envid => {
                                    self.validate_argument(
                                        0,
                                        Capability::EnvelopeDsn.into(),
                                        line_num,
                                        line_pos,
                                    )?;
                                }
                                _ => (),
                            }
                        }

                        envelope_list = envelopes.into();
                    } else {
                        key_list = self.parse_strings_token(token_info)?;
                        break;
                    }
                }
            }
        }
        self.validate_match(&match_type, &mut key_list)?;

        Ok(Test::Envelope(TestEnvelope {
            envelope_list: envelope_list.unwrap(),
            key_list,
            address_part,
            match_type,
            comparator,
            zone,
            is_not: false,
        }))
    }
}

impl TryFrom<String> for Envelope {
    type Error = String;

    fn try_from(value: String) -> Result<Self, Self::Error> {
        if let Some(envelope) = ENVELOPE.get(&value) {
            Ok(*envelope)
        } else {
            Err(value)
        }
    }
}

impl<'x> TryFrom<&'x str> for Envelope {
    type Error = &'x str;

    fn try_from(value: &'x str) -> Result<Self, Self::Error> {
        if let Some(envelope) = ENVELOPE.get(value) {
            Ok(*envelope)
        } else {
            Err(value)
        }
    }
}

pub(crate) static ENVELOPE: phf::Map<&'static str, Envelope> = phf_map! {
    "from" => Envelope::From,
    "to" => Envelope::To,
    "bytimeabsolute" => Envelope::ByTimeAbsolute,
    "bytimerelative" => Envelope::ByTimeRelative,
    "bymode" => Envelope::ByMode,
    "bytrace" => Envelope::ByTrace,
    "notify" => Envelope::Notify,
    "orcpt" => Envelope::Orcpt,
    "ret" => Envelope::Ret,
    "envid" => Envelope::Envid,
};