//go:build ignore

// genlect-of generates the OF (Ordinary Form) temporal lectionary from
// niedziela.pl (via internal/readings): Sundays & solemnities keyed by
// <Observed.Slug>-<SundayCycle> (A/B/C), ferial weekdays by <ferial-slug>-
// <WeekdayCycle> (I/II). Only TRUE ferials are harvested for the weekday table;
// memorial days are skipped (their readings come from the ferial fallback at
// runtime). One-time; requires network. Run from the repo root:
//
//	go run scripts/genlect-of.go
//
// Writes internal/caldata/of-lectionary.ini.
package main

import (
	"fmt"
	"os"
	"regexp"
	"sort"
	"strings"
	"time"

	"github.com/lukaszkasprzak/lectio/internal/bible"
	"github.com/lukaszkasprzak/lectio/internal/caldata"
	"github.com/lukaszkasprzak/lectio/internal/calendar"
	"github.com/lukaszkasprzak/lectio/internal/config"
	"github.com/lukaszkasprzak/lectio/internal/readings"
)

// bookCommaRe strips a stray comma between the book name and the first
// chapter ("4 Kings, 5:1-15" -> "4 Kings 5:1-15"), a source data glitch.
// The [^:] guard means it only fires before any chapter:verse, so legitimate
// multi-chapter commas ("Gen 1:1, 2:3") are left intact.
// Copied verbatim from scripts/genlect.go.
var bookCommaRe = regexp.MustCompile(`^([^:]*?),\s+(\d+:)`)

// chapDotRe rewrites a European-style "chapter. verse" separator to a colon
// ("John 20. 19-31" -> "John 20:19-31"), another source data glitch. It is
// applied only when the citation carries no colon at all, so disjoint verse
// groups in a normal citation ("Ps 62:2. 3-4") are never touched.
// Copied verbatim from scripts/genlect.go.
var chapDotRe = regexp.MustCompile(`(\d+)\.\s+(\d)`)

func cleanCite(s string) string {
	s = bookCommaRe.ReplaceAllString(strings.TrimSpace(s), "$1 $2")
	if !strings.Contains(s, ":") {
		s = chapDotRe.ReplaceAllString(s, "$1:$2")
	}
	return s
}

// numBookSpaceRe restores the space niedziela sometimes drops in a numbered
// book sigil ("1J 3,11" -> "1 J 3,11"; "2Kor" -> "2 Kor") so ToEnglishRef's
// Polish table (keyed "1 J", "2 Kor", …) matches. Applied to the raw Polish
// citation BEFORE ToEnglishRef.
var numBookSpaceRe = regexp.MustCompile(`^(\d)([^\d\s])`)

// sourceGlitches are exact niedziela sigla-casing glitches that don't match the
// ToEnglishRef Polish table (which is Title-case). E.g. "PnP" for Song of Songs.
var sourceGlitches = map[string]string{"PnP": "Pnp"}

// fixSourceCite normalises a raw niedziela citation before ToEnglishRef.
func fixSourceCite(s string) string {
	s = numBookSpaceRe.ReplaceAllString(strings.TrimSpace(s), "$1 $2")
	for bad, good := range sourceGlitches {
		if strings.HasPrefix(s, bad+" ") {
			s = good + s[len(bad):]
		}
	}
	return s
}

// partIDToPart maps a niedziela.pl (liturgy.Section) PartID to our lectionary
// field name. Anything absent (e.g. "aklamacja") is not a reading and is
// ignored.
var partIDToPart = map[string]string{
	"pierwsze_czytanie": "first",
	"psalm":             "psalm",
	"drugie_czytanie":   "second",
	"ewangelia":         "gospel",
}

func main() {
	sel := calendar.DefaultSelection()
	sel.Form = "new"
	layers := []calendar.Layer{caldata.Universal()}

	cfg := config.Default()
	cfg.Lectionary = "new"

	lect := map[string]map[string]string{} // key -> part -> citation
	seen := map[string]bool{}
	missing := map[string]string{} // key -> last failure reason; cleared on success

	// niedziela only publishes ~6 weeks ahead, so future years are unavailable;
	// the cycles repeat, so a liturgical position's readings are identical
	// whichever civil year they fall in. Harvest 2018-2025 -- TWO+ years per
	// cycle (Sunday A:2020,2023 B:2021,2024 C:2022,2025; weekday I:2021,2023,2025
	// II:2020,2022,2024) so a position displaced by a saint/feast in one year is
	// still captured in another. A key is stored from the FIRST year it resolves;
	// a year where it fails does not block a later retry (seen is set on success).
	start := time.Date(2018, 1, 1, 0, 0, 0, 0, time.UTC)
	end := time.Date(2025, 12, 31, 0, 0, 0, 0, time.UTC)

	for d := start; !d.After(end); d = d.AddDate(0, 0, 1) {
		full := calendar.Compute(d, sel, layers)
		sunOrSol := d.Weekday() == time.Sunday ||
			full.Observed.Rank == calendar.RankSolemnity ||
			full.Observed.Rank == calendar.RankFeast

		var key string
		if sunOrSol {
			key = full.Observed.Slug + "-" + full.SundayCycle
		} else if full.Observed.Rank == calendar.RankFerial && full.Observed.Layer == "temporal" {
			// A true ferial (incl. optional-memorial days, where the ferial is the
			// observed default): niedziela shows the ferial readings.
			key = full.Observed.Slug + "-" + full.WeekdayCycle
		} else {
			// Obligatory memorial: SKIP. Most memorials read the ferial of the
			// DAY, which varies year to year (the fixed feast date lands in a
			// different Ordinary-Time week each year) -- so keying by the saint
			// slug would freeze one year's ferial and be wrong in others. At
			// runtime the resolver falls the memorial back to the day's ferial
			// slug, which resolves to the correct week's reading. (Proper-reading
			// memorials therefore show the ferial, a permitted OF option; their
			// propers are a later refinement.)
			continue
		}
		if seen[key] {
			continue // already stored from an earlier year
		}

		dateStr := d.Format("2006-01-02")
		secs, _, err := readings.Load(cfg, readings.Options{Date: dateStr, All: true})
		if err != nil {
			fmt.Fprintf(os.Stderr, "%s %-32s ERROR readings.Load: %v\n", dateStr, key, err)
			missing[key] = fmt.Sprintf("%s (readings.Load error: %v)", dateStr, err)
			continue
		}

		parts := map[string]string{}
		for _, s := range secs {
			part, ok := partIDToPart[s.PartID]
			if !ok {
				continue
			}
			system := ""
			if part == "psalm" {
				system = "drb"
			}
			eng, err := bible.ToEnglishRef(fixSourceCite(s.Citation), system)
			if err != nil {
				fmt.Fprintf(os.Stderr, "%s %-32s part=%-6s citation=%q: ToEnglishRef error: %v\n",
					dateStr, key, part, s.Citation, err)
				continue
			}
			parts[part] = cleanCite(eng)
		}

		if parts["first"] == "" || parts["gospel"] == "" {
			missing[key] = fmt.Sprintf("%s (first=%q gospel=%q)", dateStr, parts["first"], parts["gospel"])
			continue // require at least first+gospel to store the entry
		}

		lect[key] = parts
		seen[key] = true     // store from the first year it resolves; stop retrying
		delete(missing, key) // a later year succeeded; not actually missing
		fmt.Fprintf(os.Stderr, "%s %-32s first=%-22s psalm=%-22s second=%-22s gospel=%s\n",
			dateStr, key, parts["first"], parts["psalm"], parts["second"], parts["gospel"])
	}

	keys := make([]string, 0, len(lect))
	for k := range lect {
		keys = append(keys, k)
	}
	sort.Strings(keys)

	var b strings.Builder
	b.WriteString("; OF (Ordinary Form) temporal lectionary, keyed by <computed-temporal-slug>-<cycle>:\n")
	b.WriteString("; Sundays & solemnities use the Sunday cycle (A/B/C), ferial weekdays the weekday\n")
	b.WriteString("; cycle (I/II). Citations English-canonical.\n")
	b.WriteString("; Generated from niedziela.pl by scripts/genlect-of.go (harvest 2018-2025).\n")
	for _, k := range keys {
		v := lect[k]
		fmt.Fprintf(&b, "\n[%s]\n", k)
		for _, part := range []string{"first", "psalm", "second", "gospel"} {
			if c := v[part]; c != "" {
				fmt.Fprintf(&b, "%s = %s\n", part, c)
			}
		}
	}
	if err := os.WriteFile("internal/caldata/of-lectionary.ini", []byte(b.String()), 0o644); err != nil {
		fmt.Fprintln(os.Stderr, err)
		os.Exit(1)
	}

	fmt.Fprintf(os.Stderr, "\nwrote %d OF temporal entries\n", len(lect))
	if len(missing) > 0 {
		mk := make([]string, 0, len(missing))
		for k := range missing {
			mk = append(mk, k)
		}
		sort.Strings(mk)
		fmt.Fprintf(os.Stderr, "%d keys NEVER resolved in any harvest year:\n", len(missing))
		for _, k := range mk {
			fmt.Fprintf(os.Stderr, "  %-34s %s\n", k, missing[k])
		}
	}
}