Files
go-caatsm/internal/adapter/parser/weather/taf_parser.go
T
2025-12-24 17:05:51 +08:00

338 lines
9.3 KiB
Go

package weather
import (
"caatsm/internal/domain/weather"
"fmt"
"strconv"
"strings"
"time"
)
// parseTaf parses a TAF report
func parseTaf(raw string) (*weather.Taf, error) {
tokens := Tokenize(raw)
if len(tokens) < 4 {
return nil, weather.ErrInvalidFormat
}
taf, pos, err := parseTafHeader(tokens, raw)
if err != nil {
return nil, err
}
// Parse main forecast period (before any FM/TEMPO/BECMG)
mainPeriod := weather.TafPeriod{
Type: "MAIN",
ValidFrom: taf.ValidFrom,
ValidTo: taf.ValidTo,
}
// Find first special section
firstSpecialIdx := len(tokens)
for i := pos; i < len(tokens); i++ {
upperToken := strings.ToUpper(tokens[i])
if strings.HasPrefix(upperToken, "FM") ||
strings.HasPrefix(upperToken, "TEMPO") ||
strings.HasPrefix(upperToken, "BECMG") ||
strings.HasPrefix(upperToken, "PROB") ||
strings.HasPrefix(upperToken, "RMK") {
firstSpecialIdx = i
break
}
}
// Parse main period tokens
if firstSpecialIdx > pos {
if firstSpecialIdx < len(tokens) {
upperToken := strings.ToUpper(tokens[firstSpecialIdx])
if strings.HasPrefix(upperToken, "FM") {
if match := tafFMPattern.FindStringSubmatch(tokens[firstSpecialIdx]); match != nil {
day, _ := strconv.Atoi(match[1])
hour, _ := strconv.Atoi(match[2])
min, _ := strconv.Atoi(match[3])
fmStart := resolveDayTime(taf.ValidFrom, day, hour, min)
if fmStart.Before(mainPeriod.ValidTo) {
mainPeriod.ValidTo = fmStart
}
}
}
}
mainTokens := tokens[pos:firstSpecialIdx]
parsePeriodElements(mainTokens, &mainPeriod, &taf.Warnings)
taf.Periods = append(taf.Periods, mainPeriod)
pos = firstSpecialIdx
}
// Parse special sections (FM, TEMPO, BECMG)
var pendingProb int
for pos < len(tokens) {
upperToken := strings.ToUpper(tokens[pos])
switch {
case strings.HasPrefix(upperToken, "PROB"):
// PROB30 or PROB40 - probability for next period
probStr := strings.TrimPrefix(upperToken, "PROB")
pendingProb, _ = strconv.Atoi(probStr)
pos++
case strings.HasPrefix(upperToken, "FM"):
period, newPos, err := parseFMPeriod(tokens, pos, taf.ValidFrom, taf.ValidTo, &taf.Warnings)
if err != nil {
taf.Warnings = append(taf.Warnings, fmt.Sprintf("failed to parse FM period: %v", err))
pos++
continue
}
if pendingProb > 0 {
period.Probability = pendingProb
pendingProb = 0
}
taf.Periods = append(taf.Periods, period)
pos = newPos
case strings.HasPrefix(upperToken, "TEMPO"):
period, newPos, err := parseTEMPOPeriod(tokens, pos, taf.ValidFrom, &taf.Warnings)
if err != nil {
taf.Warnings = append(taf.Warnings, fmt.Sprintf("failed to parse TEMPO period: %v", err))
pos++
continue
}
if pendingProb > 0 {
period.Probability = pendingProb
pendingProb = 0
}
taf.Periods = append(taf.Periods, period)
pos = newPos
case strings.HasPrefix(upperToken, "BECMG"):
period, newPos, err := parseBECMGPeriod(tokens, pos, taf.ValidFrom, &taf.Warnings)
if err != nil {
taf.Warnings = append(taf.Warnings, fmt.Sprintf("failed to parse BECMG period: %v", err))
pos++
continue
}
if pendingProb > 0 {
period.Probability = pendingProb
pendingProb = 0
}
taf.Periods = append(taf.Periods, period)
pos = newPos
case strings.HasPrefix(upperToken, "RMK"):
// Remarks section - include RMK token and all following tokens
taf.Remarks = strings.Join(tokens[pos:], " ")
// Set pos to exit the loop
pos = len(tokens)
default:
// Unrecognized token
taf.Warnings = append(taf.Warnings, fmt.Sprintf("unrecognized token: %s", tokens[pos]))
pos++
}
}
return taf, nil
}
func parseTafHeader(tokens []string, raw string) (*weather.Taf, int, error) {
taf := &weather.Taf{
ReportType: weather.ReportTypeTAF,
RawTextVal: raw,
Warnings: []string{},
Periods: []weather.TafPeriod{},
}
pos := 0
if pos >= len(tokens) {
return nil, 0, weather.ErrMissingStation
}
pos++
if pos >= len(tokens) {
return nil, 0, weather.ErrMissingStation
}
taf.StationID = tokens[pos]
pos++
if pos >= len(tokens) {
return nil, 0, weather.ErrMissingTime
}
issueTime, err := ParseTime(tokens[pos])
if err != nil {
return nil, 0, fmt.Errorf("failed to parse issue time: %w", err)
}
taf.IssueTimeVal = issueTime
pos++
if pos >= len(tokens) {
return nil, 0, fmt.Errorf("missing validity period")
}
validFrom, validTo, err := ParseTAFValidity(tokens[pos], taf.IssueTimeVal)
if err != nil {
return nil, 0, fmt.Errorf("failed to parse validity period: %w", err)
}
taf.ValidFrom = validFrom
taf.ValidTo = validTo
pos++
return taf, pos, nil
}
func resolveDayTime(base time.Time, day, hour, min int) time.Time {
t := time.Date(base.Year(), base.Month(), day, hour, min, 0, 0, time.UTC)
if day < base.Day() {
t = t.AddDate(0, 1, 0)
}
return t
}
// parseFMPeriod parses an FM (from) period
func parseFMPeriod(tokens []string, startPos int, validityFrom, validityTo time.Time, warnings *[]string) (weather.TafPeriod, int, error) {
period := weather.TafPeriod{
Type: "FM",
}
match := tafFMPattern.FindStringSubmatch(tokens[startPos])
if len(match) == 0 {
return period, startPos + 1, fmt.Errorf("invalid FM format")
}
day, _ := strconv.Atoi(match[1])
hour, _ := strconv.Atoi(match[2])
min, _ := strconv.Atoi(match[3])
period.ValidFrom = resolveDayTime(validityFrom, day, hour, min)
period.ValidTo = validityTo
// Find end of this period (next FM, TEMPO, BECMG, or end)
endPos := len(tokens)
for i := startPos + 1; i < len(tokens); i++ {
upperToken := strings.ToUpper(tokens[i])
if strings.HasPrefix(upperToken, "FM") ||
strings.HasPrefix(upperToken, "TEMPO") ||
strings.HasPrefix(upperToken, "BECMG") ||
strings.HasPrefix(upperToken, "RMK") {
endPos = i
break
}
}
// Parse period elements
periodTokens := tokens[startPos+1 : endPos]
parsePeriodElements(periodTokens, &period, warnings)
// Set valid_to to start of next period or end of validity
if endPos < len(tokens) {
upperToken := strings.ToUpper(tokens[endPos])
if strings.HasPrefix(upperToken, "FM") {
// Next period starts here
if match := tafFMPattern.FindStringSubmatch(tokens[endPos]); match != nil {
nextDay, _ := strconv.Atoi(match[1])
nextHour, _ := strconv.Atoi(match[2])
nextMin, _ := strconv.Atoi(match[3])
nextStart := resolveDayTime(period.ValidFrom, nextDay, nextHour, nextMin)
if nextStart.Before(period.ValidTo) {
period.ValidTo = nextStart
}
}
}
}
return period, endPos, nil
}
// parseTEMPOPeriod parses a TEMPO (temporary) period
func parseTEMPOPeriod(tokens []string, startPos int, validityFrom time.Time, warnings *[]string) (weather.TafPeriod, int, error) {
period := weather.TafPeriod{
Type: "TEMPO",
}
match := tafTEMPOPattern.FindStringSubmatch(tokens[startPos])
if len(match) == 0 {
return period, startPos + 1, fmt.Errorf("invalid TEMPO format")
}
fromDay, _ := strconv.Atoi(match[1])
fromHour, _ := strconv.Atoi(match[2])
toDay, _ := strconv.Atoi(match[3])
toHour, _ := strconv.Atoi(match[4])
period.ValidFrom = resolveDayTime(validityFrom, fromDay, fromHour, 0)
period.ValidTo = resolveDayTime(period.ValidFrom, toDay, toHour, 0)
// Find end of this period
endPos := startPos + 1
for endPos < len(tokens) {
upperToken := strings.ToUpper(tokens[endPos])
if strings.HasPrefix(upperToken, "FM") ||
strings.HasPrefix(upperToken, "TEMPO") ||
strings.HasPrefix(upperToken, "BECMG") ||
strings.HasPrefix(upperToken, "RMK") {
break
}
endPos++
}
// Parse period elements
periodTokens := tokens[startPos+1 : endPos]
parsePeriodElements(periodTokens, &period, warnings)
return period, endPos, nil
}
// parseBECMGPeriod parses a BECMG (becoming) period
func parseBECMGPeriod(tokens []string, startPos int, validityFrom time.Time, warnings *[]string) (weather.TafPeriod, int, error) {
period := weather.TafPeriod{
Type: "BECMG",
}
match := tafBECMGPattern.FindStringSubmatch(tokens[startPos])
if len(match) == 0 {
return period, startPos + 1, fmt.Errorf("invalid BECMG format")
}
fromDay, _ := strconv.Atoi(match[1])
fromHour, _ := strconv.Atoi(match[2])
toDay, _ := strconv.Atoi(match[3])
toHour, _ := strconv.Atoi(match[4])
period.ValidFrom = resolveDayTime(validityFrom, fromDay, fromHour, 0)
period.ValidTo = resolveDayTime(period.ValidFrom, toDay, toHour, 0)
// Find end of this period
endPos := startPos + 1
for endPos < len(tokens) {
upperToken := strings.ToUpper(tokens[endPos])
if strings.HasPrefix(upperToken, "FM") ||
strings.HasPrefix(upperToken, "TEMPO") ||
strings.HasPrefix(upperToken, "BECMG") ||
strings.HasPrefix(upperToken, "RMK") {
break
}
endPos++
}
// Parse period elements
periodTokens := tokens[startPos+1 : endPos]
parsePeriodElements(periodTokens, &period, warnings)
return period, endPos, nil
}
// parsePeriodElements parses common elements (wind, visibility, clouds, phenomena) for a TAF period
func parsePeriodElements(tokens []string, period *weather.TafPeriod, warnings *[]string) {
pos, wind, visibility := parseWindAndVisibility(tokens)
period.Wind = wind
period.Visibility = visibility
phenomConsumed, phenomena := parsePhenomena(tokens[pos:])
period.Phenomena = append(period.Phenomena, phenomena...)
pos += phenomConsumed
cloudConsumed, clouds := parseClouds(tokens[pos:])
period.Clouds = append(period.Clouds, clouds...)
pos += cloudConsumed
appendPeriodWarnings(warnings, tokens[pos:])
}