You are extracting bibliographic metadata from legislation text.

You may be given contextual hints (filename, source URL) alongside document text or its opening and closing excerpts. The document text is authoritative — use the hints only to resolve ambiguity.

Extract these fields. Use the text exactly as it appears — do not invent or guess values. If a field is not present in the text, use an empty string.

Fields:
- title: The formal short title (e.g., "Police Act", "Companies Act 2006"). Look for "This Act may be cited as..." or the title page. Do not use the filename.
- date: The date of enactment, issuance, or signing of this instrument as printed in the document; use an explicitly printed commencement date only if none of those is stated. Distinguish this instrument from cited instruments: a date belonging to a cited resolution, earlier law, or other reference is not this instrument’s date. Do not calculate a date from a relative effectivity clause or treat a technical digital-signature timestamp alone as proof of enactment or issuance. If no qualifying date is stated, use an empty string. Use ISO 8601 (YYYY-MM-DD) if Gregorian. For Hijri dates, use the Hijri year (e.g., "1443"). For other calendars, use the year as printed.
- year: The enactment year as printed in the document. For Gregorian: "2025". For Hijri: "1443". For Japanese: extract the Gregorian year if shown (e.g., "Act No. 78 of 2006" → "2006"), otherwise the era year WITH its era name (e.g., "Reiwa 6" or "令和6"), because the number alone is ambiguous between eras. For Minguo/ROC: the year as printed (e.g., "114"). For Buddhist Era: "2565". Just the number and no prefix, with the single exception of the Japanese era name above, which is part of the year.
- number: The act number WITHOUT the year. Extract only the sequential number. "Act No. 6 of 2025" → "6". "Act 2024-28" → "28". "Royal Decree No. M/73" → "73". For amendment bills without an act number, use empty string.
- chapter: The chapter/Cap number if used (e.g., "167", "308"). Extract the bare number only.
- is_amendment: true if this amends another act, false otherwise. Look for "Amendment Act", "is hereby amended", "to amend the...", "Loi modifiant", "تعديل".
- language: ISO 639-3 code for the document's primary language, judged from the bulk of the operative text — NOT the filename, NOT the script of cited statute titles, stamps, or seals, NOT any English summary the source site appended. Examples: "ara" (Arabic), "eng" (English), "fra" (French), "ukr" (Ukrainian), "sqi" (Albanian), "deu" (German), "spa" (Spanish), "rus" (Russian), "heb" (Hebrew), "zho" (Chinese). For bilingual or parallel-column documents (e.g. Canadian English/French acts, EU directives published in two languages), pick the language carrying the majority of the operative text. Empty string only if the text is too short to judge.
- additional_languages: List of ISO 639-3 codes for any other languages present in non-trivial quantities (parallel column, multilingual schedules, substantive bilingual enacting clauses). Empty list when the document is effectively monolingual. Do not list a language merely because a few foreign-script terms or citations appear inline.
- calendar: The calendar `date` and `year` are expressed in. One of: "gregorian", "hijri" (lunar Hijri / AH), "hijri_solar" (Iranian Solar Hijri / SH), "ethiopian", "buddhist", "japanese_era", "minguo" (Republic of China / Taiwan), or "" if too short to judge. Detect from context — years 1300–1500 with an Arabic-Islamic context are almost always Hijri (corresponds to 1880s–2070s Gregorian). Years 1300–1500 in a European context are Gregorian. Iranian instruments often use Solar Hijri (year 1300s–1400s corresponds to 1920s–2020s Gregorian). Japanese era names ("令和", "平成", "昭和", "Reiwa", "Heisei", "Showa") signal japanese_era. Thai years 2400–2600 signal buddhist. A Taiwanese instrument dated in a low year ("中華民國114年", "114") signals minguo. Default to "gregorian" when in doubt and the document is post-1900 in date.

Respond with a single JSON object (not an array) containing exactly these fields.
