feat: Detect mountain pass crossings, name climbs after passes, render ride charts

- osmpass: extract mountain_pass=yes nodes from an OSM PBF, enrich centcols passes with OSM coordinates, resumable -fetch-osm download
- mountain_pass: DetectCrossings for a ride, MatchClimb to name a climb after the pass it tops
- ride: expose Points(), add Climb.Top() and Climb.Name
- chart: -chart renders elevation profile with climb bands and pass markers
- commands: -fetch-osm, -extract-osm, -import-cached, -enrich

1 files changed, 240 insertions, 0 deletions

diff --git a/osmpass/enrich.go b/osmpass/enrich.go
new file mode 100644
index 0000000..3af0067
--- /dev/null
+++ b/osmpass/enrich.go
@@ -0,0 +1,240 @@
+package osmpass
+
+import (
+	"database/sql"
+	"fmt"
+	"log/slog"
+	"strings"
+	"unicode"
+
+	"golang.org/x/text/unicode/norm"
+)
+
+const elevationToleranceM = 25
+
+type osmPass struct {
+	Name      string
+	Elevation *int
+	Latitude  float64
+	Longitude float64
+}
+
+func EnrichMountainPasses(db *sql.DB) (int, error) {
+	osmPasses, err := loadOSMPasses(db)
+	if err != nil {
+		return 0, err
+	}
+	rows, err := db.Query(`
+		SELECT external_id, name, department_code, elevation
+		FROM mountain_passes
+		WHERE latitude IS NULL
+	`)
+	if err != nil {
+		return 0, err
+	}
+
+	unmatched := make([]struct {
+		ExternalID     string
+		Name           string
+		DepartmentCode string
+		Elevation      int
+	}, 0)
+	for rows.Next() {
+		var candidate struct {
+			ExternalID     string
+			Name           string
+			DepartmentCode string
+			Elevation      int
+		}
+		if err := rows.Scan(&candidate.ExternalID, &candidate.Name, &candidate.DepartmentCode, &candidate.Elevation); err != nil {
+			rows.Close()
+			return 0, err
+		}
+		unmatched = append(unmatched, candidate)
+	}
+	if err := rows.Err(); err != nil {
+		rows.Close()
+		return 0, err
+	}
+	rows.Close()
+
+	statement, err := db.Prepare(`
+		UPDATE mountain_passes SET latitude = ?, longitude = ? WHERE external_id = ?
+	`)
+	if err != nil {
+		return 0, err
+	}
+	defer statement.Close()
+
+	count := 0
+	for _, candidate := range unmatched {
+		matched := matchToOSM(candidate.Name, candidate.DepartmentCode, candidate.Elevation, osmPasses)
+		if matched == nil {
+			continue
+		}
+		if _, err := statement.Exec(matched.Latitude, matched.Longitude, candidate.ExternalID); err != nil {
+			return count, err
+		}
+		count++
+	}
+	slog.Info("Enriched mountain passes with coordinates", "count", count)
+	return count, nil
+}
+
+func loadOSMPasses(db *sql.DB) ([]osmPass, error) {
+	rows, err := db.Query(`
+		SELECT name, elevation, latitude, longitude
+		FROM osm_passes
+		WHERE elevation IS NOT NULL
+	`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	osmPasses := make([]osmPass, 0)
+	for rows.Next() {
+		var mountainPass osmPass
+		var name sql.NullString
+		var elevation sql.NullInt64
+		if err := rows.Scan(&name, &elevation, &mountainPass.Latitude, &mountainPass.Longitude); err != nil {
+			return nil, err
+		}
+		mountainPass.Name = name.String
+		if elevation.Valid {
+			elevationValue := int(elevation.Int64)
+			mountainPass.Elevation = &elevationValue
+		}
+		osmPasses = append(osmPasses, mountainPass)
+	}
+	return osmPasses, rows.Err()
+}
+
+func matchToOSM(name, departmentCode string, elevation int, osmPasses []osmPass) *osmPass {
+	bbox := departmentBBox(departmentCode)
+	var best *osmPass
+	bestNameMatch := false
+	bestElevationDiff := 0.0
+	for i := range osmPasses {
+		candidate := &osmPasses[i]
+		if candidate.Elevation == nil {
+			continue
+		}
+		if !bbox.Contains(candidate.Latitude, candidate.Longitude) {
+			continue
+		}
+		elevationDiff := absFloat64(float64(elevation) - float64(*candidate.Elevation))
+		if elevationDiff > elevationToleranceM {
+			continue
+		}
+		nameMatch := nameMatches(name, candidate.Name)
+		if best == nil ||
+			(nameMatch && !bestNameMatch) ||
+			(nameMatch == bestNameMatch && elevationDiff < bestElevationDiff) {
+			best = candidate
+			bestNameMatch = nameMatch
+			bestElevationDiff = elevationDiff
+		}
+	}
+	if best == nil {
+		return nil
+	}
+	if bestNameMatch {
+		return best
+	}
+	for i := range osmPasses {
+		candidate := &osmPasses[i]
+		if candidate == best || candidate.Elevation == nil {
+			continue
+		}
+		if !bbox.Contains(candidate.Latitude, candidate.Longitude) {
+			continue
+		}
+		if absFloat64(float64(elevation)-float64(*candidate.Elevation)) <= bestElevationDiff+30 {
+			return nil
+		}
+	}
+	return best
+}
+
+type bbox struct {
+	minLat, minLon, maxLat, maxLon float64
+}
+
+func (b bbox) Contains(latitude, longitude float64) bool {
+	return latitude >= b.minLat && latitude <= b.maxLat &&
+		longitude >= b.minLon && longitude <= b.maxLon
+}
+
+func departmentBBox(departmentCode string) bbox {
+	switch departmentCode {
+	case "01":
+		return bbox{minLat: 45.5, minLon: 4.7, maxLat: 46.6, maxLon: 6.3}
+	case "06":
+		return bbox{minLat: 43.5, minLon: 6.4, maxLat: 44.5, maxLon: 7.8}
+	case "13":
+		return bbox{minLat: 43.1, minLon: 4.4, maxLat: 44.0, maxLon: 6.0}
+	default:
+		return bbox{minLat: 41.0, minLon: -6.0, maxLat: 52.0, maxLon: 10.0}
+	}
+}
+
+func nameMatches(centName, osmName string) bool {
+	cent := normalizeName(centName)
+	osm := normalizeName(osmName)
+	if cent == osm {
+		return true
+	}
+	centTokens := tokenize(cent)
+	if len(centTokens) < 3 {
+		return false
+	}
+	osmTokens := make(map[string]bool)
+	for _, token := range tokenize(osm) {
+		osmTokens[token] = true
+	}
+	for _, token := range centTokens {
+		if !osmTokens[token] {
+			return false
+		}
+	}
+	return true
+}
+
+func tokenize(name string) []string {
+	return strings.Fields(name)
+}
+
+func normalizeName(name string) string {
+	name = strings.ToLower(name)
+	name = norm.NFD.String(name)
+	normalized := strings.Builder{}
+	previousSpace := false
+	for _, r := range name {
+		if unicode.Is(unicode.Mn, r) {
+			continue
+		}
+		if unicode.IsLetter(r) || unicode.IsDigit(r) {
+			normalized.WriteRune(r)
+			previousSpace = false
+		} else if !previousSpace {
+			normalized.WriteRune(' ')
+			previousSpace = true
+		}
+	}
+	return strings.TrimSpace(normalized.String())
+}
+
+func absFloat64(value float64) float64 {
+	if value < 0 {
+		return -value
+	}
+	return value
+}
+
+func (p osmPass) String() string {
+	if p.Elevation == nil {
+		return fmt.Sprintf("%s @ unknown elevation", p.Name)
+	}
+	return fmt.Sprintf("%s @ %dm", p.Name, *p.Elevation)
+}