1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167

use chrono::{Datelike, NaiveDate, NaiveDateTime, NaiveTime, Timelike};

use crate::{
    error::{err_column_null, err_type_conv},
    ibase, Column, ColumnToVal, FbError, IntoParam, SqlType,
};

const FRACTION_TO_NANOS: u32 = 1e9 as u32 / ibase::ISC_TIME_SECONDS_PRECISION;

/// Convert a numeric day to [day, month, year]. (Ported from the firebird source)
///
/// Calenders are divided into 4 year cycles: 3 non-leap years, and 1 leap year.
/// Each cycle takes 365*4 + 1 == 1461 days.
/// There is a further cycle of 100 4 year cycles.
/// Every 100 years, the normally expected leap year is not present. Every 400 years it is.
/// This cycle takes 100 * 1461 - 3 == 146097 days.
/// The origin of the constant 2400001 is unknown.
/// The origin of the constant 1721119 is unknown.
/// The difference between 2400001 and 1721119 is the
/// number of days from 0/0/0000 to our base date of 11/xx/1858 (678882)
/// The origin of the constant 153 is unknown.
///
/// This whole routine has problems with ndates less than -678882 (Approx 2/1/0000).
pub fn decode_date(date: ibase::ISC_DATE) -> NaiveDate {
    let mut nday = date;

    nday += 2400001 - 1721119;

    let century = (4 * nday - 1) / 146097;
    nday = 4 * nday - 1 - 146097 * century;

    let mut day = nday / 4;
    nday = (4 * day + 3) / 1461;
    day = 4 * day + 3 - 1461 * nday;
    day = (day + 4) / 4;

    let mut month = (5 * day - 3) / 153;
    day = 5 * day - 3 - 153 * month;
    day = (day + 5) / 5;

    let mut year = 100 * century + nday;

    if month < 10 {
        month += 3;
    } else {
        month -= 9;
        year += 1;
    };

    chrono::NaiveDate::from_ymd(year, month as u32, day as u32)
}

/// Convert a [day, month, year] to numeric day (Ported from the firebird source)
pub fn encode_date(date: NaiveDate) -> ibase::ISC_DATE {
    let day = date.day() as i64;
    let mut month = date.month() as i64;
    let mut year = date.year() as i64;

    if month > 2 {
        month -= 3;
    } else {
        month += 9;
        year -= 1;
    }

    let c = year / 100;
    let ya = year - 100 * c;

    ((146097 * c) as i64 / 4 + (1461 * ya) / 4 + (153 * month + 2) / 5 + day + 1721119 - 2400001)
        as ibase::ISC_DATE
}

/// Convert a numeric time to [hours, minutes, seconds] (Ported from the firebird source)
pub fn decode_time(time: ibase::ISC_TIME) -> NaiveTime {
    let mut ntime = time;

    let hours = ntime / (3600 * ibase::ISC_TIME_SECONDS_PRECISION);
    ntime %= 3600 * ibase::ISC_TIME_SECONDS_PRECISION;

    let minutes = ntime / (60 * ibase::ISC_TIME_SECONDS_PRECISION);
    ntime %= 60 * ibase::ISC_TIME_SECONDS_PRECISION;

    let seconds = ntime / ibase::ISC_TIME_SECONDS_PRECISION;

    let fraction = ntime % ibase::ISC_TIME_SECONDS_PRECISION;

    chrono::NaiveTime::from_hms_nano(hours, minutes, seconds, fraction * FRACTION_TO_NANOS)
}

/// Convert a [hours, minutes, seconds] to a numeric time (Ported from the firebird source)
pub fn encode_time(time: chrono::NaiveTime) -> ibase::ISC_TIME {
    let hours = time.hour();
    let minutes = time.minute();
    let seconds = time.second();
    let fraction = time.nanosecond() / FRACTION_TO_NANOS;

    ((hours * 60 + minutes) * 60 + seconds) * ibase::ISC_TIME_SECONDS_PRECISION + fraction
}

/// Convert a numeric timestamp to a DateTime
pub fn decode_timestamp(ts: ibase::ISC_TIMESTAMP) -> NaiveDateTime {
    decode_date(ts.timestamp_date).and_time(decode_time(ts.timestamp_time))
}

/// Convert a DateTime to a numeric timestamp
pub fn encode_timestamp(dt: NaiveDateTime) -> ibase::ISC_TIMESTAMP {
    ibase::ISC_TIMESTAMP {
        timestamp_date: encode_date(dt.date()),
        timestamp_time: encode_time(dt.time()),
    }
}

impl IntoParam for NaiveDateTime {
    fn into_param(self) -> SqlType {
        SqlType::Timestamp(self)
    }
}

impl IntoParam for NaiveDate {
    fn into_param(self) -> SqlType {
        // Mimics firebird conversion
        self.and_time(NaiveTime::from_hms(0, 0, 0)).into_param()
    }
}

impl IntoParam for NaiveTime {
    fn into_param(self) -> SqlType {
        // Mimics firebird conversion
        chrono::Utc::today().naive_utc().and_time(self).into_param()
    }
}

impl ColumnToVal<chrono::NaiveDate> for Column {
    fn to_val(self) -> Result<chrono::NaiveDate, FbError> {
        match self.value {
            SqlType::Timestamp(ts) => Ok(ts.date()),

            SqlType::Null => Err(err_column_null("NaiveDate")),

            col => err_type_conv(col, "NaiveDate"),
        }
    }
}

impl ColumnToVal<chrono::NaiveTime> for Column {
    fn to_val(self) -> Result<chrono::NaiveTime, FbError> {
        match self.value {
            SqlType::Timestamp(ts) => Ok(ts.time()),

            SqlType::Null => Err(err_column_null("NaiveTime")),

            col => err_type_conv(col, "NaiveTime"),
        }
    }
}

impl ColumnToVal<chrono::NaiveDateTime> for Column {
    fn to_val(self) -> Result<chrono::NaiveDateTime, FbError> {
        match self.value {
            SqlType::Timestamp(ts) => Ok(ts),

            SqlType::Null => Err(err_column_null("NaiveDateTime")),

            col => err_type_conv(col, "NaiveDateTime"),
        }
    }
}