OpenHistoricalMap · erictheise · Dec 20, 2023 · Dec 17, 2023
diff --git a/modules/util/date.js b/modules/util/date.js
@@ -0,0 +1,241 @@
+import edtf, { Interval } from 'edtf';
+
+// Returns whether two date component arrays represent the same date.
+// A date component array contains the full date, followed by year, month, day.
+// Dates are only compared to the lowest common precision.
+function isSameDate(date1, date2) {
+    if (date1[1] !== date2[1]) return false;
+    if (date1[2] && date2[2] && date1[2] !== date2[2]) return false;
+    if (date1[3] && date2[3] && date1[3] !== date2[3]) return false;
+    return true;
+}
+
+function isBefore(date1, date2) {
+    if (date1[1] > date2[1]) return false;
+    if (date1[2] && date2[2] && date1[2] > date2[2]) return false;
+    if (date1[3] && date2[3] && date1[3] > date2[3]) return false;
+    return true;
+}
+
+function isAfter(date1, date2) {
+    if (date1[1] < date2[1]) return false;
+    if (date1[2] && date2[2] && date1[2] < date2[2]) return false;
+    if (date1[3] && date2[3] && date1[3] < date2[3]) return false;
+    return true;
+}
+
+/**
+ * Returns whether the two sets of tags overlap temporally.
+ *
+ * @param {object} tags1 Tags to compare.
+ * @param {object} tags2 Tags to compare.
+ * @param {boolean?} touchIsOverlap True to consider it an overlap if one date range ends at the same time that the other begins.
+ */
+export function utilDatesOverlap(tags1, tags2, touchIsOverlap) {
+    // If the feature has a valid start date but no valid end date, assume it
+    // starts at the beginning of time.
+    var dateRegex = /^(-?\d{1,4})(?:-(\d\d))?(?:-(\d\d))?$/;
+    var minDate = ['-9999', '-9999'],
+        maxDate = ['9999', '9999'],
+        start1 = (tags1.start_date || '').match(dateRegex) || minDate,
+        start2 = (tags2.start_date || '').match(dateRegex) || minDate,
+        end1 = (tags1.end_date || '').match(dateRegex) || maxDate,
+        end2 = (tags2.end_date || '').match(dateRegex) || maxDate;
+
+    if (isSameDate(end1, start2) || isSameDate(end2, start1)) {
+        return touchIsOverlap === true;
+    }
+
+    return ((isAfter(start1, start2) && isBefore(start1, end2)) ||
+            (isAfter(start2, start1) && isBefore(start2, end1)) ||
+            (isAfter(end1, start2) && isBefore(end1, end2)) ||
+            (isAfter(end2, start1) && isBefore(end2, end1)));
+}
+
+// Returns an object containing the given date string normalized as an ISO 8601 date string and parsed as a Date object.
+// Date components are padded for compatibility with tagging conventions.
+// Dates such as January 0, February 31, and Duodecember 1 are wrapped to make more sense.
+export function utilNormalizeDateString(raw) {
+    if (!raw) return null;
+
+    var date;
+
+    // Enforce the same date formats supported by DateFunctions-plpgsql and decimaldate-python.
+    var dateRegex = /^(-)?(\d+)(?:-(\d\d?)(?:-(\d\d?))?)?$/;
+    var match = raw.match(dateRegex);
+    if (match !== null) {
+        // Manually construct a Date.
+        // Passing the string directly into the Date constructor would throw an error on negative years.
+        date = new Date(0);
+        date.setUTCFullYear(parseInt((match[1] || '') + match[2], 10));
+        if (match[3]) date.setUTCMonth(parseInt(match[3], 10) - 1); // 0-based
+        if (match[4]) date.setUTCDate(parseInt(match[4], 10));
+    } else {
+        // Fall back on whatever the browser can parse into a date.
+        date = new Date(raw);
+        try {
+            date.toISOString();
+        } catch (exc) {
+            return null;
+        }
+    }
+
+    // Reconstruct the date string.
+    // Avoid Date.toISOString() because it has fixed precision and excessively pads negative years.
+    var normalized = '';
+    if (match !== null && date.getUTCFullYear() < 0) {
+        var absYear = Math.abs(date.getUTCFullYear());
+        normalized += '-' + String(absYear).padStart(4, '0');
+    } else {
+        normalized += String(date.getUTCFullYear()).padStart(4, '0');
+    }
+    if (match === null || match[3]) {
+        normalized += '-' + String(date.getUTCMonth() + 1).padStart(2, '0');
+    }
+    if (match === null || match[4]) {
+        normalized += '-' + String(date.getUTCDate()).padStart(2, '0');
+    }
+    return {
+        date: date,
+        value: normalized,
+        localeOptions: {
+            year: 'numeric',
+            era: date.getUTCFullYear() < 1 ? 'short' : undefined,
+            month: (match === null || match[3]) ? 'long' : undefined,
+            day: (match === null || match[4]) ? 'numeric' : undefined,
+            timeZone: 'UTC'
+        }
+    };
+}
+
+/**
+ * Converts a date in OSM approximate date format to EDTF.
+ */
+export function utilEDTFFromOSMDateString(osm) {
+    // https://wiki.openstreetmap.org/wiki/Key:start_date#Approximations
+    // https://wiki.openstreetmap.org/wiki/Special:Diff/510218/557626#Proposal_for_date_formatting
+    // https://www.loc.gov/standards/datetime/
+    let [match, start, end, bc] = osm.match(/^(.+)\.\.(.+)( BCE?)?$/) || [];
+    if (match) {
+        if (!bc) bc = '';
+        let startEDTF = utilEDTFFromOSMDateString(start + bc);
+        if (startEDTF) {
+            let parsed = edtf(startEDTF);
+            if (parsed instanceof Set) {
+                startEDTF = parsed.earlier ? '' : parsed.first.edtf;
+            }
+            if (parsed instanceof Interval) {
+                startEDTF = parsed.earlier ? '' : parsed.lower.edtf;
+            }
+        }
+
+        let endEDTF = utilEDTFFromOSMDateString(end + bc);
+        if (endEDTF) {
+            let parsed = edtf(endEDTF);
+            if (parsed instanceof Set) {
+                endEDTF = parsed.later ? '' : parsed.last.edtf;
+            }
+            if (parsed instanceof Interval) {
+                endEDTF = parsed.later ? '' : parsed.upper.edtf;
+            }
+        }
+
+        if (startEDTF && endEDTF) {
+            if (startEDTF.match(/[~?%]/) || endEDTF.match(/[~?%]/)) {
+                // Set notation is incompatible with qualifiers.
+                return `${startEDTF}/${endEDTF}`;
+            } else {
+                return `[${startEDTF}..${endEDTF}]`;
+            }
+        }
+    }
+
+    let year, circa, monthDay;
+    [match, circa, year, monthDay, bc] = osm.match(/^(~)?(\d+)(-\d\d(?:-\d\d)?)?( BCE?)?$/) || [];
+    if (match) {
+        if (!circa) circa = '';
+        if (!monthDay) monthDay = '';
+        if (bc) {
+            year = '-' + String(parseInt(year, 10) - 1).padStart(4, '0');
+        } else {
+            year = year.padStart(4, '0');
+        }
+        return `${year}${monthDay}${circa}`;
+    }
+
+    let decade;
+    [match, circa, decade, bc] = osm.match(/^(~)?(\d+)0s( BCE?)?$/) || [];
+    if (match) {
+        if (!circa) circa = '';
+        if (!bc) {
+            return `${decade.padStart(3, '0')}X${circa}`;
+        }
+        let startYear = String(parseInt(decade, 10) * 10 + 8).padStart(4, '0');
+        let endYear = String(parseInt(decade, 10) * 10 - 1).padStart(4, '0');
+        return `-${startYear}${circa}/-${endYear}${circa}`;
+    }
+
+    let century;
+    [match, circa, century, bc] = osm.match(/^(~)?C(\d+)( BCE?)?$/) || [];
+    if (match) {
+        if (!circa) circa = '';
+        if (!bc) {
+            return `${String(parseInt(century, 10) - 1).padStart(2, '0')}XX${circa}`;
+        }
+        let startYear = String((parseInt(century, 10) - 1) * 100 + 98).padStart(4, '0');
+        let endYear = String((parseInt(century, 10) - 1) * 100 - 1).padStart(4, '0');
+        return `-${startYear}${circa}/-${endYear}${circa}`;
+    }
+
+    let third;
+    [match, third, decade, bc] = osm.match(/^(early|mid|late) (\d+)0s( BCE?)?$/) || [];
+    if (match) {
+        // https://uhlibraries-digital.github.io/bcdams-map/guidelines/date
+        const offsetsByThird = {
+            early: [0, 3],
+            mid: [3, 7],
+            late: [7, 9],
+        };
+
+        let startYear = decade * 10 + offsetsByThird[third][bc ? 1 : 0];
+        let endYear = decade * 10 + offsetsByThird[third][bc ? 0 : 1];
+        if (bc) {
+            startYear = startYear + 1;
+            endYear = endYear + 1;
+            return `-${String(startYear).padStart(4, '0')}~/-${String(endYear).padStart(4, '0')}~`;
+        } else {
+            return `${String(startYear).padStart(4, '0')}~/${String(endYear).padStart(4, '0')}~`;
+        }
+    }
+
+    [match, third, century, bc] = osm.match(/^(early|mid|late) C(\d+)( BCE?)?$/) || [];
+    if (match) {
+        // https://uhlibraries-digital.github.io/bcdams-map/guidelines/date
+        const offsetsByThird = {
+            early: [0, 30],
+            mid: [30, 70],
+            late: [70, 99],
+        };
+
+        century = parseInt(century, 10) - 1;
+        let startYear = century * 100 + offsetsByThird[third][bc ? 1 : 0];
+        let endYear = century * 100 + offsetsByThird[third][bc ? 0 : 1];
+        if (bc) {
+            startYear = startYear + 1;
+            endYear = endYear + 1;
+            return `-${String(startYear).padStart(4, '0')}~/-${String(endYear).padStart(4, '0')}~`;
+        } else {
+            return `${String(startYear).padStart(4, '0')}~/${String(endYear).padStart(4, '0')}~`;
+        }
+    }
+
+    [match, end] = osm.match(/^before (\d{4}(?:-\d\d)?(?:-\d\d)?)$/) || [];
+    if (match) {
+        return `[..${end}]`;
+    }
+
+    [match, start] = osm.match(/^after (\d{4}(?:-\d\d)?(?:-\d\d)?)$/) || [];
+    if (match) {
+        return `[${start}..]`;
+    }
+}
diff --git a/modules/util/index.js b/modules/util/index.js
@@ -14,7 +14,7 @@ export { utilArrayUniqBy } from './array';
 export { utilAsyncMap } from './util';
 export { utilCleanTags } from './clean_tags';
 export { utilCombinedTags } from './util';
-export { utilDatesOverlap } from './util';
+export { utilDatesOverlap } from './date';
 export { utilDeepMemberSelector } from './util';
 export { utilDetect } from './detect';
 export { utilDisplayName } from './util';
@@ -23,6 +23,7 @@ export { utilDisplayType } from './util';
 export { utilDisplayLabel } from './util';
 export { utilEntityRoot } from './util';
 export { utilEditDistance } from './util';
+export { utilEDTFFromOSMDateString } from './date';
 export { utilEntityAndDeepMemberIDs } from './util';
 export { utilEntityOrMemberSelector } from './util';
 export { utilEntityOrDeepMemberSelector } from './util';
@@ -34,7 +35,7 @@ export { utilGetSetValue } from './get_set_value';
 export { utilHashcode } from './util';
 export { utilHighlightEntities } from './util';
 export { utilKeybinding } from './keybinding';
-export { utilNormalizeDateString } from './util';
+export { utilNormalizeDateString } from './date';
 export { utilNoAuto } from './util';
 export { utilObjectOmit } from './object';
 export { utilCompareIDs } from './util';

diff --git a/modules/util/util.js b/modules/util/util.js
@@ -4,6 +4,7 @@ import { fixRTLTextForSvg, rtlRegex } from './svg_paths_rtl_fix';
 import { presetManager } from '../presets';
 import { t, localizer } from '../core/localizer';
 import { utilArrayUnion } from './array';
+import { utilNormalizeDateString } from './date';
 import { utilDetect } from './detect';
 import { geoExtent } from '../geo/extent';
 
@@ -682,110 +683,3 @@ export function utilCleanOsmString(val, maxChars) {
     // trim to the number of allowed characters
     return utilUnicodeCharsTruncated(val, maxChars);
 }
-// Returns whether two date component arrays represent the same date.
-// A date component array contains the full date, followed by year, month, day.
-// Dates are only compared to the lowest common precision.
-function isSameDate(date1, date2) {
-    if (date1[1] !== date2[1]) return false;
-    if (date1[2] && date2[2] && date1[2] !== date2[2]) return false;
-    if (date1[3] && date2[3] && date1[3] !== date2[3]) return false;
-    return true;
-}
-
-function isBefore(date1, date2) {
-    if (date1[1] > date2[1]) return false;
-    if (date1[2] && date2[2] && date1[2] > date2[2]) return false;
-    if (date1[3] && date2[3] && date1[3] > date2[3]) return false;
-    return true;
-}
-
-function isAfter(date1, date2) {
-    if (date1[1] < date2[1]) return false;
-    if (date1[2] && date2[2] && date1[2] < date2[2]) return false;
-    if (date1[3] && date2[3] && date1[3] < date2[3]) return false;
-    return true;
-}
-
-/**
- * Returns whether the two sets of tags overlap temporally.
- *
- * @param {object} tags1 Tags to compare.
- * @param {object} tags2 Tags to compare.
- * @param {boolean?} touchIsOverlap True to consider it an overlap if one date range ends at the same time that the other begins.
- */
-export function utilDatesOverlap(tags1, tags2, touchIsOverlap) {
-    // If the feature has a valid start date but no valid end date, assume it
-    // starts at the beginning of time.
-    var dateRegex = /^(-?\d{1,4})(?:-(\d\d))?(?:-(\d\d))?$/;
-    var minDate = ['-9999', '-9999'],
-        maxDate = ['9999', '9999'],
-        start1 = (tags1.start_date || '').match(dateRegex) || minDate,
-        start2 = (tags2.start_date || '').match(dateRegex) || minDate,
-        end1 = (tags1.end_date || '').match(dateRegex) || maxDate,
-        end2 = (tags2.end_date || '').match(dateRegex) || maxDate;
-
-    if (isSameDate(end1, start2) || isSameDate(end2, start1)) {
-        return touchIsOverlap === true;
-    }
-
-    return ((isAfter(start1, start2) && isBefore(start1, end2)) ||
-            (isAfter(start2, start1) && isBefore(start2, end1)) ||
-            (isAfter(end1, start2) && isBefore(end1, end2)) ||
-            (isAfter(end2, start1) && isBefore(end2, end1)));
-}
-
-// Returns an object containing the given date string normalized as an ISO 8601 date string and parsed as a Date object.
-// Date components are padded for compatibility with tagging conventions.
-// Dates such as January 0, February 31, and Duodecember 1 are wrapped to make more sense.
-export function utilNormalizeDateString(raw) {
-    if (!raw) return null;
-
-    var date;
-
-    // Enforce the same date formats supported by DateFunctions-plpgsql and decimaldate-python.
-    var dateRegex = /^(-)?(\d+)(?:-(\d\d?)(?:-(\d\d?))?)?$/;
-    var match = raw.match(dateRegex);
-    if (match !== null) {
-        // Manually construct a Date.
-        // Passing the string directly into the Date constructor would throw an error on negative years.
-        date = new Date(0);
-        date.setUTCFullYear(parseInt((match[1] || '') + match[2], 10));
-        if (match[3]) date.setUTCMonth(parseInt(match[3], 10) - 1); // 0-based
-        if (match[4]) date.setUTCDate(parseInt(match[4], 10));
-    } else {
-        // Fall back on whatever the browser can parse into a date.
-        date = new Date(raw);
-        try {
-            date.toISOString();
-        } catch (exc) {
-            return null;
-        }
-    }
-
-    // Reconstruct the date string.
-    // Avoid Date.toISOString() because it has fixed precision and excessively pads negative years.
-    var normalized = '';
-    if (match !== null && date.getUTCFullYear() < 0) {
-        var absYear = Math.abs(date.getUTCFullYear());
-        normalized += '-' + String(absYear).padStart(4, '0');
-    } else {
-        normalized += String(date.getUTCFullYear()).padStart(4, '0');
-    }
-    if (match === null || match[3]) {
-        normalized += '-' + String(date.getUTCMonth() + 1).padStart(2, '0');
-    }
-    if (match === null || match[4]) {
-        normalized += '-' + String(date.getUTCDate()).padStart(2, '0');
-    }
-    return {
-        date: date,
-        value: normalized,
-        localeOptions: {
-            year: 'numeric',
-            era: date.getUTCFullYear() < 1 ? 'short' : undefined,
-            month: (match === null || match[3]) ? 'long' : undefined,
-            day: (match === null || match[4]) ? 'numeric' : undefined,
-            timeZone: 'UTC'
-        }
-    };
-}