物流2024〜2026年問題と「トラックGメン」対策：
拘束時間・荷待ち記録・アルコール検知・遠隔点呼を無理なく守る現場DX

#![forbid(unsafe_code)]

/// Represents a single driver duty shift in epoch minutes.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub struct DriverDutyShift {
    pub shift_id: u32,
    pub start_epoch_min: u64,
    pub end_epoch_min: u64,
    pub alcohol_brac_micro_mg_l: u32, // Must be 0 for dispatch clearance
}

#[derive(Debug, Clone, PartialEq, Eq)]
pub enum StatutoryViolation {
    InvalidShiftInterval { shift_id: u32 },
    AlcoholDetected { shift_id: u32, brac_micro_mg_l: u32 },
    DailyBindingExceeds15Hours { shift_id: u32, binding_minutes: u64 },
    InsufficientRestPeriodUnder9Hours { after_shift_id: u32, rest_minutes: u64 },
    WeeklyOver14HoursExceedsTwice { count_over_14h: usize },
}

#[derive(Debug, Clone, PartialEq, Eq)]
pub struct WeeklyComplianceReport {
    pub daily_24h_binding_minutes: Vec<u64>,
    pub over_14h_shift_count: usize,
    pub min_rest_minutes_observed: u64,
    pub violations: Vec<StatutoryViolation>,
}

pub const MINUTES_PER_24H: u64 = 1440;
pub const MAX_DAILY_BINDING_MIN: u64 = 900; — 15 hours
pub const THRESHOLD_14H_MIN: u64 = 840; — 14 hours
pub const MIN_REST_PERIOD_MIN: u64 = 540; — 9 hours minimum (11h = 660m target)

/// Evaluates a chronological sequence of weekly shifts against the 2024 Revised Driver Standards,
/// including exact 24-hour sliding window overlap when a subsequent shift starts earlier.
pub fn audit_weekly_driver_schedule(shifts: &[DriverDutyShift]) -> WeeklyComplianceReport {
    let mut violations = Vec::new();
    let mut daily_24h_binding_minutes = Vec::with_capacity(shifts.len());
    let mut over_14h_shift_count = 0usize;
    let mut min_rest_minutes_observed = u64::MAX;

    for (i, curr) in shifts.iter().enumerate() {
        if curr.end_epoch_min <= curr.start_epoch_min {
            violations.push(StatutoryViolation::InvalidShiftInterval {
                shift_id: curr.shift_id,
            });
            continue;
        }
        if curr.alcohol_brac_micro_mg_l > 0 {
            violations.push(StatutoryViolation::AlcoholDetected {
                shift_id: curr.shift_id,
                brac_micro_mg_l: curr.alcohol_brac_micro_mg_l,
            });
        }

        let window_end = curr.start_epoch_min.saturating_add(MINUTES_PER_24H);
        let mut binding_min = curr.end_epoch_min - curr.start_epoch_min;

        // Check if subsequent shifts overlap into [curr.start_epoch_min, curr.start_epoch_min + 24h]
        for next in shifts.iter().skip(i + 1) {
            if next.start_epoch_min >= window_end {
                break;
            }
            let overlap_start = next.start_epoch_min.max(curr.end_epoch_min);
            let overlap_end = next.end_epoch_min.min(window_end);
            if overlap_end > overlap_start {
                binding_min = binding_min.saturating_add(overlap_end - overlap_start);
            }
        }

        daily_24h_binding_minutes.push(binding_min);
        if binding_min > MAX_DAILY_BINDING_MIN {
            violations.push(StatutoryViolation::DailyBindingExceeds15Hours {
                shift_id: curr.shift_id,
                binding_minutes: binding_min,
            });
        }
        if binding_min > THRESHOLD_14H_MIN {
            over_14h_shift_count += 1;
        }

        if let Some(next_shift) = shifts.get(i + 1) {
            let rest_min = next_shift
                .start_epoch_min
                .saturating_sub(curr.end_epoch_min);
            if rest_min < min_rest_minutes_observed {
                min_rest_minutes_observed = rest_min;
            }
            if rest_min < MIN_REST_PERIOD_MIN {
                violations.push(StatutoryViolation::InsufficientRestPeriodUnder9Hours {
                    after_shift_id: curr.shift_id,
                    rest_minutes: rest_min,
                });
            }
        }
    }

    if over_14h_shift_count > 2 {
        violations.push(StatutoryViolation::WeeklyOver14HoursExceedsTwice {
            count_over_14h: over_14h_shift_count,
        });
    }

    WeeklyComplianceReport {
        daily_24h_binding_minutes,
        over_14h_shift_count,
        min_rest_minutes_observed: if min_rest_minutes_observed == u64::MAX {
            0
        } else {
            min_rest_minutes_observed
        },
        violations,
    }
}