bms-rs 1.0.0

//! This module handles the tokens:
//!
//! - `#BPM n` - Initial BPM definition.
//! - `#BPM[01-ZZ] n` / `#EXBPM[01-ZZ] n` - BPM change definition.
//! - `#BASEBPM` - Reference speed for scroll speed. Obsolete.
//! - `#xxx08:` - BPM change channel.

use std::{cell::RefCell, rc::Rc};

use super::{
    super::prompt::{DefDuplication, Prompter},
    ProcessContext, TokenProcessor, parse_hex_values, parse_obj_ids,
};
use crate::bms::ParseErrorWithRange;
use crate::{
    bms::{
        model::{StringValue, bpm::BpmObjects},
        parse::{ParseWarning, Result},
        prelude::*,
    },
    util::StrExtension,
};
use strict_num_extended::PositiveF64;

/// It processes `#BPM` and `#BPMxx` definitions and objects on `BpmChange` and `BpmChangeU8` channels.
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct BpmProcessor {
    case_sensitive_obj_id: Rc<RefCell<bool>>,
}

impl BpmProcessor {
    pub fn new(case_sensitive_obj_id: &Rc<RefCell<bool>>) -> Self {
        Self {
            case_sensitive_obj_id: Rc::clone(case_sensitive_obj_id),
        }
    }
}

impl TokenProcessor for BpmProcessor {
    type Output = BpmObjects;

    fn process<P: Prompter>(
        &self,
        ctx: &mut ProcessContext<'_, '_, P>,
    ) -> core::result::Result<Self::Output, ParseErrorWithRange> {
        let mut objects = BpmObjects::default();
        ctx.all_tokens(|token, prompter| match token.content() {
            Token::Header { name, args } => Ok(self
                .on_header(name.as_ref(), args.as_ref(), prompter, &mut objects)
                .err()
                .map(|warn| warn.into_wrapper(token))),
            Token::Message {
                track,
                channel,
                message,
            } => Ok(self
                .on_message(
                    *track,
                    *channel,
                    &message.as_ref().into_wrapper(token),
                    prompter,
                    &mut objects,
                )
                .err()
                .map(|warn| warn.into_wrapper(token))),
            Token::NotACommand(_) => Ok(None),
        })?;
        Ok(objects)
    }
}

impl BpmProcessor {
    fn on_header(
        &self,
        name: &str,
        args: &str,
        prompter: &impl Prompter,
        objects: &mut BpmObjects,
    ) -> Result<()> {
        if name.eq_ignore_ascii_case("BPM") {
            let string_value: StringValue<PositiveF64> = StringValue::new(args);
            objects.bpm = Some(string_value);
        }
        if let Some(id) = name
            .strip_prefix_ignore_case("BPM")
            .or_else(|| name.strip_prefix_ignore_case("EXBPM"))
        {
            let bpm_obj_id = ObjId::try_from(id, *self.case_sensitive_obj_id.borrow())?;
            let string_value: StringValue<PositiveF64> = StringValue::new(args);
            if let Some(older) = objects.bpm_defs.get_mut(&bpm_obj_id) {
                prompter
                    .handle_def_duplication(DefDuplication::BpmChange {
                        id: bpm_obj_id,
                        older,
                        newer: &string_value,
                    })
                    .apply_def(older, string_value, bpm_obj_id)?;
            } else {
                objects.bpm_defs.insert(bpm_obj_id, string_value);
            }
        }
        if name.eq_ignore_ascii_case("BASEBPM") {
            let string_value: StringValue<PositiveF64> = StringValue::new(args);
            objects.base_bpm = Some(string_value);
        }
        Ok(())
    }

    fn on_message(
        &self,
        track: Track,
        channel: Channel,
        message: &SourceRangeMixin<&str>,
        prompter: &impl Prompter,
        objects: &mut BpmObjects,
    ) -> Result<Vec<ParseWarningWithRange>> {
        let mut warnings: Vec<ParseWarningWithRange> = Vec::new();
        if channel == Channel::BpmChange {
            let (pairs, w) = parse_obj_ids(track, message, &self.case_sensitive_obj_id);
            warnings.extend(w);
            for (time, obj) in pairs {
                // Record used BPM change id for validity checks
                objects.bpm_change_ids_used.insert(obj);
                let string_value = objects
                    .bpm_defs
                    .get(&obj)
                    .ok_or(ParseWarning::UndefinedObject(obj))?;
                let Ok(&bpm) = string_value.value().as_ref() else {
                    continue;
                };
                objects.push_bpm_change(BpmChangeObj { time, bpm }, prompter)?;
            }
        }
        if channel == Channel::BpmChangeU8 {
            let (pairs, w) = parse_hex_values(track, message);
            warnings.extend(w);
            for (time, value) in pairs {
                objects.push_bpm_change_u8(time, value, prompter)?;
            }
        }
        Ok(warnings)
    }
}