// morphology-sux.el — Sumerian morphology for the NLG engine.
//
// Implements Sumerian noun declension, verb conjugation, and sentence
// construction.  Designed as a companion to morphology.el and called by
// the engine when the language profile code is "sux".
//
// Language profile: code=sux, name=Sumerian, morph_type=agglutinative,
//   word_order=SOV, question_strategy=particle, script=latin_transliteration,
//   family=isolate (no known relatives).
//
// Typological overview:
//   Sumerian is the world's oldest attested written language, first recorded
//   in Uruk ca. 3500 BCE; active spoken use through ca. 2000 BCE; learned
//   scribal language to ca. 100 CE.  It is a language isolate — unrelated to
//   any other known language family.
//
//   ERGATIVITY: Sumerian is ergative-absolutive.  The subject of a transitive
//   verb (the AGENT) takes the ergative case (-e).  The subject of an
//   intransitive verb and the direct object of a transitive verb share the
//   same form: the ABSOLUTIVE (unmarked, no suffix).  This is structurally
//   the opposite of nominative-accusative languages (like Latin or Greek)
//   where the subject of both transitive and intransitive verbs is marked the
//   same way.  Example: lugal-e é mu-un-dù = "the king built the house",
//   where lugal-e = king-ERG (agent of transitive dù "build") and é = house-ABS
//   (patient, unmarked).
//
//   NOUN CLASSES: animate (humans, gods) and inanimate (everything else).
//   Animate plurals use -ene; inanimate plurals use -a (collective).
//
//   VERB CHAIN: Sumerian finite verbs are polysynthetic chains encoding:
//     (modal)(negation)(dimensional prefixes)(stem)(voice/causative)(suffixes)
//   The dimensional prefix chain includes pronominal agreement markers for
//   agent and patient.  This module implements a simplified but linguistically
//   honest subset: perfective mu-/imperfective i- prefix + personal suffixes.
//
//   KEY VERBS: Several high-frequency verbs have frozen citation forms.
//   The copula is often omitted in equational sentences; when present it is
//   usually the clitic -am₃ or the verb me "to be".
//
//   TRANSLITERATION: Standard Assyriological transliteration uses subscript
//   numbers for sign disambiguation (dug₄, tum₂, am₃) written here with the
//   corresponding Unicode characters (dug4, tum2, am3 using ASCII where the
//   subscript forms are unavailable in string literals, or as ₄ etc. where
//   needed).  Special characters: š (sh), ŋ (velar nasal), ĝ (= ŋ alternate),
//   ḫ (voiceless velar/uvular fricative).
//
// Cases implemented:
//   absolutive (∅), ergative (-e), genitive (-ak), dative (-ra),
//   locative (-a), ablative (-ta), comitative (-da), equative (-gin)
//
// Depends on: morphology.el (str_ends_with, str_len, str_slice, str_eq,
//   native_list_empty, native_list_append, native_list_get, native_list_len)

// ── String helpers ─────────────────────────────────────────────────────────────

import "morphology.el"
fn sux_str_ends(s: String, suf: String) -> Bool {
    return str_ends_with(s, suf)
}

fn sux_str_drop_last(s: String, n: Int) -> String {
    let len: Int = str_len(s)
    if n >= len {
        return ""
    }
    return str_slice(s, 0, len - n)
}

fn sux_str_last_char(s: String) -> String {
    let n: Int = str_len(s)
    if n == 0 {
        return ""
    }
    return str_slice(s, n - 1, n)
}

fn sux_str_last2(s: String) -> String {
    let n: Int = str_len(s)
    if n < 2 {
        return s
    }
    return str_slice(s, n - 2, n)
}

// ── Person/number slot ─────────────────────────────────────────────────────────
//
// Maps person × number to a 0-based index used in paradigm tables.
//   0 = 1st singular   (ĝe₂₆ / ĝa₂ "I")
//   1 = 2nd singular   (za-e "you")
//   2 = 3rd singular   (animate: a-ne "he/she"; inanimate implied)
//   3 = 1st plural     (me "we")
//   4 = 2nd plural     (me-zen "you (pl)")
//   5 = 3rd plural     (animate: a-ne-ne "they")
//
// Dual is not grammaticalised distinctly from plural in Sumerian verbal
// morphology; dual inputs fall through to plural.

fn sux_slot(person: String, number: String) -> Int {
    if str_eq(person, "first") {
        if str_eq(number, "singular") { return 0 }
        return 3
    }
    if str_eq(person, "second") {
        if str_eq(number, "singular") { return 1 }
        return 4
    }
    // third person
    if str_eq(number, "singular") { return 2 }
    return 5
}

// ── Ergative personal suffixes ─────────────────────────────────────────────────
//
// These encode the AGENT of a transitive verb when it appears as a standalone
// noun suffix (postposition on the nominal element in the ergative chain).
// In practice the -e ergative postposition on nouns is more common; these
// pronominal suffixes appear in the verbal chain.  Provided here for the
// pronominal agent agreement slot.
//
// Ergative suffixes on nominal phrases (the postposition form, not verbal):
//   1sg: -(e)n  2sg: -(e)n  3sg animate: -e
//   1pl: -enden  2pl: -enzen  3pl animate: -eš

fn sux_ergative_suffix(person: String, number: String) -> String {
    if str_eq(person, "first") {
        if str_eq(number, "singular") { return "-en" }
        return "-enden"
    }
    if str_eq(person, "second") {
        if str_eq(number, "singular") { return "-en" }
        return "-enzen"
    }
    // third
    if str_eq(number, "singular") { return "-e" }
    return "-eš"
}

// ── Absolutive personal suffixes ──────────────────────────────────────────────
//
// The absolutive is the UNMARKED case in Sumerian ergative grammar.  It is
// used for:
//   (a) the single argument of an intransitive verb (= subject)
//   (b) the direct object of a transitive verb (= patient)
//
// There is no overt suffix on the noun in the absolutive.  However, the VERB
// agrees with the absolutive argument via a suffix in the verbal chain.
// These are the verbal agreement suffixes for the absolutive participant:
//   1sg: -en  2sg: -en  3sg: ∅ (null)  1pl: -enden  2pl: -enzen  3pl: ∅

fn sux_absolutive_suffix(person: String, number: String) -> String {
    if str_eq(person, "first") {
        if str_eq(number, "singular") { return "-en" }
        return "-enden"
    }
    if str_eq(person, "second") {
        if str_eq(number, "singular") { return "-en" }
        return "-enzen"
    }
    // third person: null agreement suffix for 3sg and 3pl
    return ""
}

// ── Canonical verb mapping ─────────────────────────────────────────────────────
//
// The semantic layer may pass English canonical labels.  Map these to the
// Sumerian citation stem (the base form as used in transliteration).

fn sux_map_canonical(verb: String) -> String {
    if str_eq(verb, "be")     { return "me" }
    if str_eq(verb, "say")    { return "dug4" }
    if str_eq(verb, "go")     { return "du" }
    if str_eq(verb, "see")    { return "igi-bar" }
    if str_eq(verb, "do")     { return "ak" }
    if str_eq(verb, "make")   { return "ak" }
    if str_eq(verb, "bring")  { return "tum2" }
    if str_eq(verb, "build")  { return "dù" }
    if str_eq(verb, "give")   { return "šum2" }
    if str_eq(verb, "know")   { return "zu" }
    if str_eq(verb, "hear")   { return "ĝeštug2 ĝar" }
    if str_eq(verb, "love")   { return "ki-aĝ2" }
    if str_eq(verb, "sit")    { return "tuš" }
    if str_eq(verb, "stand")  { return "gub" }
    if str_eq(verb, "come")   { return "ĝen" }
    if str_eq(verb, "eat")    { return "gu7" }
    if str_eq(verb, "drink")  { return "naĝ" }
    if str_eq(verb, "write")  { return "sar" }
    return verb
}

// ── Verbal personal suffixes (simplified finite chain) ────────────────────────
//
// In the simplified model the personal suffix encodes the absolutive argument
// (the subject of intransitive verbs, or the patient of transitive verbs).
// Full Sumerian verbal morphology is polysynthetic and beyond NLG scope; this
// models the most productive layer: stem + absolutive agreement.
//
// Suffix paradigm:
//   slot 0 (1sg): -en    slot 3 (1pl): -enden
//   slot 1 (2sg): -en    slot 4 (2pl): -enzen
//   slot 2 (3sg): ∅      slot 5 (3pl): -eš

fn sux_personal_suffix(slot: Int) -> String {
    if slot == 0 { return "en" }
    if slot == 1 { return "en" }
    if slot == 2 { return "" }
    if slot == 3 { return "enden" }
    if slot == 4 { return "enzen" }
    return "eš"
}

// ── Special: me (to be) ───────────────────────────────────────────────────────
//
// The Sumerian copula "me" (to be) has several uses:
//   - As a full verb with personal endings in present: me-en (I am), me-en
//     (you are), ∅ / -am3 (he/she/it is — copula often omitted or realised as
//     the clitic -am3 attached to the predicate), me-en-dè (we are)
//   - As a predicative clitic: noun/adj + -am3
//   - In past: ha-ma-an-me (he/she was — rare in NLG contexts)
//
// For NLG purposes:
//   present: use me + personal suffix; 3sg = omit entirely or "-am3" clitic
//   past:    ba-me + personal suffix (archaic; approximate)

fn sux_me_present(slot: Int) -> String {
    if slot == 0 { return "me-en" }
    if slot == 1 { return "me-en" }
    if slot == 2 { return "" }
    if slot == 3 { return "me-en-dè" }
    if slot == 4 { return "me-en-zè-en" }
    return "me-eš"
}

fn sux_me_past(slot: Int) -> String {
    if slot == 0 { return "ba-me-en" }
    if slot == 1 { return "ba-me-en" }
    if slot == 2 { return "ba-me" }
    if slot == 3 { return "ba-me-en-dè" }
    if slot == 4 { return "ba-me-en-zè-en" }
    return "ba-me-eš"
}

// ── Special: dug4/e (to say) ──────────────────────────────────────────────────
//
// "dug4" is the perfective stem; "e" is the imperfective/present stem.
// Common finite forms:
//   present (imperfective): e + personal suffix; 3sg = e
//   past (perfective):      mu-un-dug4 (3sg agent; simplified)

fn sux_dug4_present(slot: Int) -> String {
    let suf: String = sux_personal_suffix(slot)
    if str_eq(suf, "") { return "e" }
    return "e-" + suf
}

fn sux_dug4_past(slot: Int) -> String {
    let suf: String = sux_personal_suffix(slot)
    if str_eq(suf, "") { return "mu-un-dug4" }
    return "mu-un-dug4-" + suf
}

// ── Special: du (to go) ───────────────────────────────────────────────────────
//
// Intransitive motion verb.  The agent is in the absolutive.
//   present (imperfective): i-du + personal suffix
//   past (perfective):      mu-un-du + personal suffix (mu- on intransitive
//                           when the agent is 3rd person; convention varies)

fn sux_du_present(slot: Int) -> String {
    let suf: String = sux_personal_suffix(slot)
    if str_eq(suf, "") { return "i-du" }
    return "i-du-" + suf
}

fn sux_du_past(slot: Int) -> String {
    let suf: String = sux_personal_suffix(slot)
    if str_eq(suf, "") { return "mu-un-du" }
    return "mu-un-du-" + suf
}

// ── Special: igi bar (to see — "to open the eye") ────────────────────────────
//
// A compound verb: igi (eye) + bar (to open/spread).  The noun igi is the
// incorporated object; bar is the finite verb element.
//   present: igi i-bar + personal suffix
//   past:    igi mu-un-bar + personal suffix

fn sux_igibar_present(slot: Int) -> String {
    let suf: String = sux_personal_suffix(slot)
    if str_eq(suf, "") { return "igi i-bar" }
    return "igi i-bar-" + suf
}

fn sux_igibar_past(slot: Int) -> String {
    let suf: String = sux_personal_suffix(slot)
    if str_eq(suf, "") { return "igi mu-un-bar" }
    return "igi mu-un-bar-" + suf
}

// ── Special: ak (to do / make) ───────────────────────────────────────────────
//
// High-frequency transitive verb; forms the basis of many compound verbs.
//   present: i-ak + personal suffix
//   past:    mu-un-ak + personal suffix

fn sux_ak_present(slot: Int) -> String {
    let suf: String = sux_personal_suffix(slot)
    if str_eq(suf, "") { return "i-ak" }
    return "i-ak-" + suf
}

fn sux_ak_past(slot: Int) -> String {
    let suf: String = sux_personal_suffix(slot)
    if str_eq(suf, "") { return "mu-un-ak" }
    return "mu-un-ak-" + suf
}

// ── Special: tum2/de6 (to bring) ─────────────────────────────────────────────
//
// Motion verb with incorporated directionality.
//   present: i-tum2 + personal suffix
//   past:    mu-un-tum2 + personal suffix

fn sux_tum2_present(slot: Int) -> String {
    let suf: String = sux_personal_suffix(slot)
    if str_eq(suf, "") { return "i-tum2" }
    return "i-tum2-" + suf
}

fn sux_tum2_past(slot: Int) -> String {
    let suf: String = sux_personal_suffix(slot)
    if str_eq(suf, "") { return "mu-un-tum2" }
    return "mu-un-tum2-" + suf
}

// ── sux_conjugate: main conjugation entry point ───────────────────────────────
//
// verb:   Sumerian verb stem or English canonical label
// tense:  "present" | "past"
//         (Sumerian distinguishes imperfective/perfective aspect rather than
//          tense proper; "present" maps to imperfective i-, "past" to
//          perfective mu-)
// person: "first" | "second" | "third"
// number: "singular" | "plural"
//
// Returns the inflected finite verb form in standard transliteration.
// Falls back to mu- + stem for unknown verbs (productive perfective prefix).
//
// Note on ergativity in the verb chain: the prefix mu- encodes that the
// agent (ergative subject) is 3rd person in the prototypical case.  Full
// pronominal infixing in the dimensional prefix chain is not modelled here;
// the returned forms represent the 3rd-person-agent baseline with personal
// suffixes for the absolutive participant.

fn sux_conjugate(verb: String, tense: String, person: String, number: String) -> String {
    let v: String = sux_map_canonical(verb)
    let slot: Int = sux_slot(person, number)

    // ── "me" — copula / to be ────────────────────────────────────────────────
    if str_eq(v, "me") {
        if str_eq(tense, "present") { return sux_me_present(slot) }
        if str_eq(tense, "past")    { return sux_me_past(slot) }
        return sux_me_present(slot)
    }

    // ── "dug4" — to say ──────────────────────────────────────────────────────
    if str_eq(v, "dug4") {
        if str_eq(tense, "present") { return sux_dug4_present(slot) }
        if str_eq(tense, "past")    { return sux_dug4_past(slot) }
        return sux_dug4_past(slot)
    }

    // ── "du" — to go ─────────────────────────────────────────────────────────
    if str_eq(v, "du") {
        if str_eq(tense, "present") { return sux_du_present(slot) }
        if str_eq(tense, "past")    { return sux_du_past(slot) }
        return sux_du_past(slot)
    }

    // ── "igi-bar" — to see ───────────────────────────────────────────────────
    if str_eq(v, "igi-bar") {
        if str_eq(tense, "present") { return sux_igibar_present(slot) }
        if str_eq(tense, "past")    { return sux_igibar_past(slot) }
        return sux_igibar_past(slot)
    }

    // ── "ak" — to do / make ──────────────────────────────────────────────────
    if str_eq(v, "ak") {
        if str_eq(tense, "present") { return sux_ak_present(slot) }
        if str_eq(tense, "past")    { return sux_ak_past(slot) }
        return sux_ak_past(slot)
    }

    // ── "tum2" — to bring ────────────────────────────────────────────────────
    if str_eq(v, "tum2") {
        if str_eq(tense, "present") { return sux_tum2_present(slot) }
        if str_eq(tense, "past")    { return sux_tum2_past(slot) }
        return sux_tum2_past(slot)
    }

    // ── Regular fallback: prefix + stem + personal suffix ────────────────────
    //
    // For verbs not listed above, apply the productive rule:
    //   imperfective (present): i- + stem + suffix
    //   perfective (past):      mu- + stem + suffix
    //
    // The "un" infix after mu- is a 3rd-person animate patient marker that
    // appears with transitive verbs; we omit it in the generic fallback as we
    // cannot know transitivity without a lexicon.

    let suf: String = sux_personal_suffix(slot)
    if str_eq(tense, "present") {
        if str_eq(suf, "") { return "i-" + v }
        return "i-" + v + "-" + suf
    }
    // past / perfective
    if str_eq(suf, "") { return "mu-" + v }
    return "mu-" + v + "-" + suf
}

// ── Animacy detection ─────────────────────────────────────────────────────────
//
// Sumerian grammatical animacy (ANIMATE vs INANIMATE) is a binary noun class
// distinction affecting plural formation and pronominal reference.  Animate
// nouns denote humans and deities; everything else is inanimate.
//
// Heuristic: check for known divine/human markers in the noun:
//   - dingir/diĝir prefix (divine determinative, written with sign AN: 𒀭)
//   - Ends in -ra, -en (lordly epithets)
//   - Known human occupational terms as exact matches
//   - Otherwise: inanimate
//
// This is necessarily approximate without a full lexicon.  The function errs
// toward inanimate (safer default for open-class nouns).

fn sux_is_animate(noun: String) -> Bool {
    // Divine determinative in transliteration
    if sux_str_ends(noun, "diĝir")  { return true }
    if sux_str_ends(noun, "dingir") { return true }
    // Common human roles
    if str_eq(noun, "lugal")  { return true }   // king
    if str_eq(noun, "nin")    { return true }   // lady/queen
    if str_eq(noun, "en")     { return true }   // lord
    if str_eq(noun, "ensi2")  { return true }   // ruler/governor
    if str_eq(noun, "dumu")   { return true }   // son/child
    if str_eq(noun, "dam")    { return true }   // spouse/wife
    if str_eq(noun, "ama")    { return true }   // mother
    if str_eq(noun, "ad")     { return true }   // father
    if str_eq(noun, "a2-dam") { return true }   // wife (alternate)
    if str_eq(noun, "lu2")    { return true }   // man/person
    if str_eq(noun, "munus")  { return true }   // woman
    if str_eq(noun, "ur")     { return true }   // man (archaic)
    if str_eq(noun, "saĝ")    { return true }   // head → person (as noun)
    if str_eq(noun, "gudu4")  { return true }   // priest
    if str_eq(noun, "sanga")  { return true }   // temple administrator
    if str_eq(noun, "ugula")  { return true }   // overseer
    if str_eq(noun, "dub-sar") { return true }  // scribe
    if str_eq(noun, "nar")    { return true }   // singer/musician
    if str_eq(noun, "sukkal") { return true }   // minister/vizier
    // Check for divine name prefix d (determinative before proper names)
    if sux_str_ends(noun, "d-") { return true }
    // Otherwise: inanimate
    return false
}

// ── Case suffixes ─────────────────────────────────────────────────────────────
//
// Sumerian is ergative-absolutive.  The cases below are postpositional clitics
// attached to the last element of the noun phrase.
//
//   absolutive:  ∅  (unmarked — subject of intransitive, object of transitive)
//   ergative:   -e  (subject of transitive verb — the AGENT)
//   genitive:  -ak  (possession, association; often written -a(k) before consonant)
//   dative:    -ra  (indirect object, beneficiary, "for/to")
//   locative:   -a  (location "in/at/on"; -e before certain consonants)
//   ablative:  -ta  (source, separation "from")
//   comitative: -da  (accompaniment "with")
//   equative:  -gin  (comparison "like/as")
//
// Note: in connected speech the genitive -ak loses its final -k before a
// consonant; this simplification uses the full form throughout.

fn sux_case_suffix(gram_case: String) -> String {
    if str_eq(gram_case, "absolutive")  { return "" }
    if str_eq(gram_case, "ergative")    { return "-e" }
    if str_eq(gram_case, "genitive")    { return "-ak" }
    if str_eq(gram_case, "dative")      { return "-ra" }
    if str_eq(gram_case, "locative")    { return "-a" }
    if str_eq(gram_case, "ablative")    { return "-ta" }
    if str_eq(gram_case, "comitative")  { return "-da" }
    if str_eq(gram_case, "equative")    { return "-gin" }
    // Terminative (-še3: "to/toward") — also attested
    if str_eq(gram_case, "terminative") { return "-še" }
    return ""
}

// ── sux_decline: noun declension ─────────────────────────────────────────────
//
// noun:      base form of the noun (absolutive singular = citation form)
// gram_case: one of the cases listed above
// number:    "singular" | "plural"
//
// Plural formation:
//   Animate nouns: base + -ene  (e.g. lugal-ene "kings")
//   Inanimate nouns: base + -a  (collective/inanimate plural; less common,
//     many inanimate nouns are not pluralised at all in Sumerian)
//
// The case suffix attaches AFTER the plural marker.
//
// Absolutive singular = the bare stem (no suffix added).

fn sux_decline(noun: String, gram_case: String, number: String) -> String {
    let csuf: String = sux_case_suffix(gram_case)
    if str_eq(number, "singular") {
        // Absolutive singular: bare stem with no suffix at all
        if str_eq(gram_case, "absolutive") { return noun }
        // Strip the leading dash from the suffix for direct concatenation
        let suf_len: Int = str_len(csuf)
        let bare_suf: String = str_slice(csuf, 1, suf_len)
        return noun + bare_suf
    }
    // Plural
    let animate: Bool = sux_is_animate(noun)
    let plural_stem: String = ""
    if animate {
        let plural_stem = noun + "ene"
    }
    if !animate {
        let plural_stem = noun + "a"
    }
    if str_eq(gram_case, "absolutive") { return plural_stem }
    let suf_len2: Int = str_len(csuf)
    let bare_suf2: String = str_slice(csuf, 1, suf_len2)
    return plural_stem + bare_suf2
}

// ── sux_noun_phrase: noun phrase builder ─────────────────────────────────────
//
// Sumerian has NO articles (definite or indefinite).  Determinateness is
// expressed through context, position, or the genitive construction.
// The "definite" parameter is accepted for interface compatibility but is
// ignored — the returned form is always the declined noun alone.
//
// noun:      base (absolutive) form
// gram_case: grammatical case string
// number:    "singular" | "plural"
// definite:  ignored (Sumerian has no articles)

fn sux_noun_phrase(noun: String, gram_case: String, number: String, definite: String) -> String {
    return sux_decline(noun, gram_case, number)
}

// ── sux_verb_chain: build the finite verbal complex ───────────────────────────
//
// Constructs the full Sumerian SOV clause for a transitive or intransitive
// predication.  Sumerian word order is strict SOV.
//
// For TRANSITIVE sentences (ergative construction):
//   agent (in ergative case: noun + -e) + patient (absolutive) + verb
//   Example: lugal-e é mu-un-dù
//            king-ERG house-ABS built
//            "The king built the house."
//
// For INTRANSITIVE sentences:
//   agent (in absolutive case: bare noun) + verb
//   Example: lugal du
//             king-ABS went
//             "The king went."
//
// agent:    the subject noun (base/absolutive form); ergative suffix applied here
// verb:     Sumerian verb stem or canonical English label
// patient:  patient noun (absolutive; pass "" for intransitive)
// tense:    "present" | "past"
//
// Note: this function handles third-person singular agreement throughout, which
// is the most common narrative form in Sumerian texts.  The conjugated verb
// form uses sux_conjugate with "third"/"singular" for the absolutive agreement.

fn sux_verb_chain(agent: String, verb: String, patient: String, tense: String) -> String {
    let conjugated: String = sux_conjugate(verb, tense, "third", "singular")
    // Intransitive: agent in absolutive + verb
    if str_eq(patient, "") {
        return agent + " " + conjugated
    }
    // Transitive: agent in ergative + patient in absolutive + verb
    // Apply ergative suffix directly (no leading dash needed — it is -e)
    let agent_erg: String = agent + "e"
    return agent_erg + " " + patient + " " + conjugated
}

// ── sux_realize_sentence: top-level sentence realizer ────────────────────────
//
// Assembles a complete Sumerian sentence from semantic components.
//
// intent:    "assert" | "question" | "describe"
// agent:     subject noun (base form)
// predicate: verb stem / canonical label (for assert/question) OR
//            adjective/noun predicate (for describe / nominal sentence)
// patient:   object noun (base form); pass "" for intransitive or nominal sentence
// tense:     "present" | "past"
//
// ── assert (declarative transitive/intransitive) ─────────────────────────────
//   Builds the SOV verb chain using sux_verb_chain.
//   Ergative marking is applied to the agent when a patient is present.
//   Example: lugal-e é mu-un-dù  "The king built the house."
//
// ── question ─────────────────────────────────────────────────────────────────
//   Sumerian polar questions are formed by appending the enclitic -a to the
//   verb (written -am₃ in some analyses; here "-a" on the verb complex).
//   Word order is unchanged (SOV retained).
//   Example: lugal-e é mu-un-dù-a?  "Did the king build the house?"
//
// ── describe (nominal/equational sentence) ──────────────────────────────────
//   Sumerian equational sentences (X is Y) typically omit the copula entirely
//   or append -am₃ to the predicate nominal/adjective.
//   Form: agent + predicate + "-am3"
//   Example: lugal-am3  "He is a king." / lugal kalag-ga-am3  "The king is mighty."
//
//   When a patient is provided in describe mode, it is treated as the predicate
//   complement: agent + patient-am3.

fn sux_realize_sentence(intent: String, agent: String, predicate: String, patient: String, tense: String) -> String {
    if str_eq(intent, "assert") {
        return sux_verb_chain(agent, predicate, patient, tense)
    }
    if str_eq(intent, "question") {
        // Build the assertion first, then append the question enclitic -a
        let assertion: String = sux_verb_chain(agent, predicate, patient, tense)
        return assertion + "-a"
    }
    if str_eq(intent, "describe") {
        // Nominal/equational sentence: agent predicate/patient + copula clitic -am3
        // When patient is given it serves as the predicate nominal
        if str_eq(patient, "") {
            return agent + " " + predicate + "-am3"
        }
        return agent + " " + patient + "-am3"
    }
    // Fallback: plain assertion
    return sux_verb_chain(agent, predicate, patient, tense)
}