From 5d0bf09430d54d77ae998f2af24be686798f32b5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Minh=20Nguy=E1=BB=85n?= <mxn@1ec5.org>
Date: Sun, 17 Dec 2023 01:28:17 -0800
Subject: [PATCH] Extract EDTF date from OSM approximate date

---
 modules/validations/invalid_format.js | 98 +++++++++++++++++++++++----
 1 file changed, 85 insertions(+), 13 deletions(-)

diff --git a/modules/validations/invalid_format.js b/modules/validations/invalid_format.js
index 50e596791c6..f6db1aaf356 100644
--- a/modules/validations/invalid_format.js
+++ b/modules/validations/invalid_format.js
@@ -8,6 +8,51 @@ import * as edtf from 'edtf';
 export function validationFormatting() {
     var type = 'invalid_format';
 
+    /**
+     * Converts a date in OSM approximate date format to EDTF.
+     */
+    function edtfFromOSMDate(osm) {
+        // https://wiki.openstreetmap.org/wiki/Key:start_date#Approximations
+        // https://wiki.openstreetmap.org/wiki/Special:Diff/510218/557626#Proposal_for_date_formatting
+        let [match, year, bc] = osm.match(/^~(\d+)( BC)?$/) || [];
+        if (match) {
+            if (bc) year = -parseInt(year, 10) + 1;
+            return `${year}~`;
+        }
+
+        let circa, decade;
+        [match, circa, decade, bc] = osm.match(/^(~)?(\d+)0s( BC)?$/) || [];
+        if (match) {
+            if (!circa) circa = '';
+            if (!bc) return `${decade}X${circa}`;
+            let startYear = -parseInt(decade, 10) * 10 - 8;
+            let endYear = -parseInt(decade, 10) * 10 + 1;
+            return `${startYear}${circa}/${endYear}${circa}`;
+        }
+
+        let century;
+        [match, circa, century, bc] = osm.match(/^(~)?C(\d+)( BC)?$/) || [];
+        if (match) {
+            if (!circa) circa = '';
+            if (!bc) return `${parseInt(century, 10) - 1}XX${circa}`;
+            let startYear = (parseInt(century, 10) - 1) * -100 - 98;
+            let endYear = (parseInt(century, 10) - 1) * -100 + 1;
+            return `${startYear}${circa}/${endYear}${circa}`;
+        }
+
+        let end;
+        [match, end] = osm.match(/^before (\d{4}(?:-\d\d)?(?:-\d\d)?)$/) || [];
+        if (match) {
+            return `[..${end}]`;
+        }
+
+        let start;
+        [match, start] = osm.match(/^after (\d{4}(?:-\d\d)?(?:-\d\d)?)$/) || [];
+        if (match) {
+            return `[${start}..]`;
+        }
+    }
+
     var validation = function(entity) {
         var issues = [];
 
@@ -38,21 +83,47 @@ export function validationFormatting() {
                 hash: key + entity.tags[key],
                 dynamicFixes: function() {
                     var fixes = [];
+
+                    let alternatives = [];
                     if (normalized !== null) {
-                        var localeDateString = normalized.date.toLocaleDateString(localizer.languageCode(), normalized.localeOptions);
-                        fixes.push(new validationIssueFix({
-                            title: t.append('issues.fix.reformat_date.title', { date: localeDateString }),
-                            onClick: function(context) {
-                                context.perform(function(graph) {
-                                    var entityInGraph = graph.hasEntity(entity.id);
-                                    if (!entityInGraph) return graph;
-                                    var newTags = Object.assign({}, entityInGraph.tags);
-                                    newTags[key] = normalized.value;
-                                    return actionChangeTags(entityInGraph.id, newTags)(graph);
-                                }, t('issues.fix.reformat_date.annotation'));
-                            }
-                        }));
+                        let label = normalized.date.toLocaleDateString(localizer.languageCode(), normalized.localeOptions);
+                        alternatives.push({
+                            date: normalized.value,
+                            label: label || normalized.value,
+                        });
                     }
+                    let edtfFromOSM = edtfFromOSMDate(entity.tags[key]);
+                    if (edtfFromOSM) {
+                        let label;
+                        try {
+                            label = edtf.default(edtfFromOSM).format(localizer.languageCode());
+                        } catch (e) {
+                            label = edtfFromOSM;
+                        }
+                        alternatives.push({
+                            edtf: edtfFromOSM,
+                            label: label,
+                        });
+                    }
+
+                    fixes.push(...alternatives.map(alt => new validationIssueFix({
+                        title: t.append('issues.fix.reformat_date.title', { date: alt.label }),
+                        onClick: function(context) {
+                            context.perform(function(graph) {
+                                var entityInGraph = graph.hasEntity(entity.id);
+                                if (!entityInGraph) return graph;
+                                var newTags = Object.assign({}, entityInGraph.tags);
+                                if (alt.date) {
+                                    newTags[key] = alt.date;
+                                } else {
+                                    delete newTags[key];
+                                }
+                                newTags[key + ':edtf'] = alt.edtf;
+                                return actionChangeTags(entityInGraph.id, newTags)(graph);
+                            }, t('issues.fix.reformat_date.annotation'));
+                        }
+                    })));
+
                     fixes.push(new validationIssueFix({
                         icon: 'iD-operation-delete',
                         title: t.append('issues.fix.remove_tag.title'),
@@ -66,6 +137,7 @@ export function validationFormatting() {
                             }, t('issues.fix.remove_tag.annotation'));
                         }
                     }));
+
                     return fixes;
                 }
             }));