import json
from pathlib import Path

import typer

from tht.cli.config_cmd import CONFIG_OPT
from tht.cli.schema_cmd import _load_config_or_exit

session_app = typer.Typer(help="Sessioni (directory artefatti)")


def session_dir(cfg, session_id: str) -> Path:
    return cfg.paths.sessions / session_id


def load_session_or_exit(cfg, session_id: str):
    from tht.session.store import SessionError, load_session

    try:
        return load_session(session_id, cfg.paths.sessions)
    except SessionError as e:
        typer.secho(f"ERRORE: {e}", fg=typer.colors.RED, err=True)
        raise typer.Exit(code=1)


def _list_sessions(sessions_root: Path) -> list[dict]:
    """Return session summary dicts sorted by created_at desc (pure helper, no I/O side-effects)."""
    from tht.session.models import SessionManifest

    MANIFEST_NAME = "session_manifest.yaml"
    out = []
    if not sessions_root.exists():
        return out
    for d in sessions_root.iterdir():
        manifest_path = d / MANIFEST_NAME
        if not manifest_path.exists():
            continue
        m = SessionManifest.from_yaml(manifest_path)
        out.append({
            "id": m.id,
            "status": m.status,
            "question": m.question,
            "summary": m.summary,
            "created_at": m.created_at.isoformat(),
            "updated_at": m.updated_at.isoformat() if m.updated_at else None,
            "author": m.author,
            "name": m.name,
            "group": m.group,
            "archived": m.archived,
        })
    out.sort(key=lambda r: r["created_at"], reverse=True)
    return out


@session_app.command("list")
def list_cmd(
    json_out: bool = typer.Option(False, "--json", help="Emetti JSON su stdout (pristine)."),
    config: Path = CONFIG_OPT,
) -> None:
    """Elenca le sessioni esistenti."""
    cfg = _load_config_or_exit(config)
    rows = _list_sessions(cfg.paths.sessions)
    if json_out:
        typer.echo(json.dumps(rows, ensure_ascii=False, indent=2))
        return
    for r in rows:
        typer.echo(f"{r['id']}  [{r['status']}]  {r['summary'] or r['question'][:60]}")


@session_app.command("new")
def new_cmd(
    question: str = typer.Argument(..., help="La domanda in linguaggio naturale."),
    provider: str = typer.Option(None, "--provider", help="Provider LLM (es. zai, anthropic)."),
    model: str = typer.Option(None, "--model", help="Modello LLM (es. glm-5.2)."),
    thinking: str = typer.Option(None, "--thinking", help="Livello di thinking (es. medium)."),
    name: str = typer.Option(None, "--name", help="Nome descrittivo della sessione."),
    json_out: bool = typer.Option(False, "--json", help="Emetti JSON puro {\"id\": ...} su stdout."),
    config: Path = CONFIG_OPT,
) -> None:
    """Crea una sessione e stampa il suo id (ultima riga dell'output)."""
    from tht.session.store import _extract_name, create_session

    cfg = _load_config_or_exit(config)
    manifest = create_session(question, cfg.database, cfg.paths.sessions,
                              provider=provider, model=model, thinking=thinking,
                              name=name or _extract_name(question))
    if json_out:
        typer.echo(json.dumps({"id": manifest.id}, ensure_ascii=False))
        return
    typer.secho(f"OK: sessione creata in {session_dir(cfg, manifest.id)}", fg=typer.colors.GREEN)
    typer.echo(manifest.id)


@session_app.command("set-question")
def set_question_cmd(
    session_id: str = typer.Argument(...),
    question: str = typer.Option(..., "--question", "-q",
                                 help="La domanda riscritta (chiara)."),
    assumption: list[str] = typer.Option(
        None, "--assumption", "-a",
        help="Una assunzione (ripetibile). Testo libero, già formattato."),
    config: Path = CONFIG_OPT,
) -> None:
    """Scrive question.md (domanda riscritta + assunzioni) in modo deterministico."""
    from tht.session.store import set_question

    cfg = _load_config_or_exit(config)
    load_session_or_exit(cfg, session_id)
    path = set_question(session_id, question, assumption or [], cfg.paths.sessions)
    typer.secho(f"OK: question.md aggiornato ({path}).", fg=typer.colors.GREEN)


@session_app.command("set-schema-linking")
def set_schema_linking_cmd(
    session_id: str = typer.Argument(...),
    file: str = typer.Option(
        ..., "--file", "-f",
        help="Path al JSON dello schema-linking, oppure '-' per leggere da stdin."),
    config: Path = CONFIG_OPT,
) -> None:
    """Valida (modello SchemaLinking) e scrive schema_linking.json deterministicamente."""
    import sys

    from pydantic import ValidationError

    from tht.session.store import set_schema_linking

    cfg = _load_config_or_exit(config)
    load_session_or_exit(cfg, session_id)
    raw = sys.stdin.read() if file == "-" else Path(file).read_text()
    try:
        data = json.loads(raw)
    except json.JSONDecodeError as e:
        typer.secho(f"ERRORE: JSON non valido: {e}", fg=typer.colors.RED, err=True)
        raise typer.Exit(code=5)
    try:
        path = set_schema_linking(session_id, data, cfg.paths.sessions)
    except ValidationError as e:
        typer.secho(f"ERRORE: schema_linking non valido:\n{e}", fg=typer.colors.RED, err=True)
        raise typer.Exit(code=5)
    typer.secho(f"OK: schema_linking.json aggiornato ({path}).", fg=typer.colors.GREEN)


@session_app.command("sync-schema-linking")
def sync_schema_linking_cmd(
    session_id: str = typer.Argument(...),
    config: Path = CONFIG_OPT,
) -> None:
    """Riproietta schema_linking.json dalle decisioni F4 del ledger (deterministico)."""
    from pydantic import ValidationError

    from tht.session.store import sync_schema_linking

    cfg = _load_config_or_exit(config)
    load_session_or_exit(cfg, session_id)
    try:
        path = sync_schema_linking(session_id, cfg.paths.sessions)
    except ValidationError as e:
        typer.secho(f"ERRORE: schema_linking non valido:\n{e}", fg=typer.colors.RED, err=True)
        raise typer.Exit(code=5)
    typer.secho(f"OK: schema_linking.json riproiettato ({path}).", fg=typer.colors.GREEN)


@session_app.command("show")
def show_cmd(
    session_id: str = typer.Argument(...),
    json_out: bool = typer.Option(False, "--json", help="Emetti JSON su stdout (pristine)."),
    config: Path = CONFIG_OPT,
) -> None:
    """Stato della sessione: manifest + decisioni registrate (per la ripresa)."""
    from tht.decisions import list_decisions
    from tht.phase import current_phase

    cfg = _load_config_or_exit(config)
    manifest = load_session_or_exit(cfg, session_id)
    sdir = session_dir(cfg, session_id)

    if json_out:
        has_schema_linking = (sdir / "schema_linking.json").exists()
        phase = current_phase(sdir)
        data = manifest.model_dump(mode="json", by_alias=True)
        data["phase"] = phase
        data["has_schema_linking"] = has_schema_linking
        typer.echo(json.dumps(data, ensure_ascii=False, indent=2))
        return

    decisions = list_decisions(sdir)
    typer.echo(f"id       : {manifest.id}")
    typer.echo(f"stato    : {manifest.status}")
    typer.echo(f"domanda  : {manifest.question}")
    typer.echo(f"target   : {manifest.database} / {manifest.db_schema}")
    typer.echo(f"decisioni: {len(decisions)}")
    for d in decisions[-10:]:
        typer.echo(f"  [{d.seq}] {d.type}: {d.subject}" + (f" — {d.detail}" if d.detail else ""))
    linking = sdir / "schema_linking.json"
    typer.echo(f"schema_linking.json: {'presente' if linking.exists() else 'assente'}")


@session_app.command("close")
def close_cmd(session_id: str = typer.Argument(...), config: Path = CONFIG_OPT) -> None:
    """Chiude la sessione (status=closed)."""
    from tht.session.store import close_session

    cfg = _load_config_or_exit(config)
    load_session_or_exit(cfg, session_id)
    close_session(session_id, cfg.paths.sessions)
    typer.secho(f"OK: sessione {session_id} chiusa.", fg=typer.colors.GREEN)


@session_app.command("set-name")
def set_name_cmd(
    session_id: str = typer.Argument(...),
    name: str = typer.Option(..., "--name", help="Nome descrittivo (vuoto = azzera)."),
    config: Path = CONFIG_OPT,
) -> None:
    """Imposta il nome descrittivo della sessione."""
    from tht.session.store import set_name

    cfg = _load_config_or_exit(config)
    load_session_or_exit(cfg, session_id)
    set_name(session_id, name, cfg.paths.sessions)
    typer.secho(f"OK: nome aggiornato per {session_id}.", fg=typer.colors.GREEN)


@session_app.command("set-group")
def set_group_cmd(
    session_id: str = typer.Argument(...),
    group: str = typer.Option(..., "--group", help="Nome del gruppo (vuoto = nessun gruppo)."),
    config: Path = CONFIG_OPT,
) -> None:
    """Sposta la sessione in un gruppo (o la toglie da ogni gruppo)."""
    from tht.session.store import set_group

    cfg = _load_config_or_exit(config)
    load_session_or_exit(cfg, session_id)
    set_group(session_id, group, cfg.paths.sessions)
    typer.secho(f"OK: gruppo aggiornato per {session_id}.", fg=typer.colors.GREEN)


@session_app.command("archive")
def archive_cmd(session_id: str = typer.Argument(...), config: Path = CONFIG_OPT) -> None:
    """Archivia la sessione (la toglie dalla lista attiva, sola lettura)."""
    from tht.session.store import set_archived

    cfg = _load_config_or_exit(config)
    load_session_or_exit(cfg, session_id)
    set_archived(session_id, True, cfg.paths.sessions)
    typer.secho(f"OK: sessione {session_id} archiviata.", fg=typer.colors.GREEN)


@session_app.command("unarchive")
def unarchive_cmd(session_id: str = typer.Argument(...), config: Path = CONFIG_OPT) -> None:
    """Ripristina la sessione dall'archivio (non ne cambia la ripristinabilità)."""
    from tht.session.store import set_archived

    cfg = _load_config_or_exit(config)
    load_session_or_exit(cfg, session_id)
    set_archived(session_id, False, cfg.paths.sessions)
    typer.secho(f"OK: sessione {session_id} ripristinata.", fg=typer.colors.GREEN)


@session_app.command("delete")
def delete_cmd(session_id: str = typer.Argument(...), config: Path = CONFIG_OPT) -> None:
    """Elimina definitivamente la cartella di sessione."""
    from tht.session.store import delete_session

    cfg = _load_config_or_exit(config)
    load_session_or_exit(cfg, session_id)
    delete_session(session_id, cfg.paths.sessions)
    typer.secho(f"OK: sessione {session_id} eliminata.", fg=typer.colors.GREEN)


@session_app.command("documents")
def documents_cmd(
    session_id: str = typer.Argument(...),
    json_out: bool = typer.Option(False, "--json", help="Emetti JSON su stdout (pristine)."),
    config: Path = CONFIG_OPT,
) -> None:
    """Documenti di sola lettura della sessione (domanda, rivista, schema, SQL, report, decisioni)."""
    from tht.session.store import build_documents

    cfg = _load_config_or_exit(config)
    manifest = load_session_or_exit(cfg, session_id)
    docs = build_documents(manifest, session_dir(cfg, session_id))
    if json_out:
        typer.echo(json.dumps(docs, ensure_ascii=False, indent=2))
        return
    for d in docs:
        typer.echo(f"[{d['phase']}] {d['title']} ({d['format']})")


def session_problems(cfg, session_id: str) -> list[str]:
    """Problemi del Blocco 3 (decisioni + schema_linking). Riusato da check e finalize."""
    import json

    from pydantic import ValidationError

    from tht.decisions import list_decisions
    from tht.session.models import SchemaLinking

    sdir = session_dir(cfg, session_id)
    problems: list[str] = []
    if not list_decisions(sdir):
        problems.append("nessuna decisione registrata (review_decisions.jsonl vuoto o assente)")
    linking_path = sdir / "schema_linking.json"
    if not linking_path.exists():
        problems.append("schema_linking.json assente")
    else:
        try:
            SchemaLinking.model_validate(json.loads(linking_path.read_text()))
        except (json.JSONDecodeError, ValidationError) as e:
            problems.append(f"schema_linking.json non valido: {e}")
    return problems


@session_app.command("check")
def check_cmd(session_id: str = typer.Argument(...), config: Path = CONFIG_OPT) -> None:
    """Gate oggettivo: decisioni presenti e schema_linking.json valido (dalla Fase 4)."""
    from tht.phase import current_phase
    from tht.workflow import load_workflow

    cfg = _load_config_or_exit(config)
    load_session_or_exit(cfg, session_id)
    cur = current_phase(session_dir(cfg, session_id))
    wf = load_workflow()
    schema_linking_phase = wf.schema_linking_phase()
    if cur < schema_linking_phase:
        # Prima della fase schema-linking non e' ancora atteso: il gate Blocco 3
        # non e' applicabile. Riportarlo come errore manderebbe il workflow in loop.
        nome = wf.phase_name(cur)
        typer.secho(
            f"Sessione {session_id} in Fase {cur} ({nome}): il gate Blocco 3 "
            f"(schema_linking.json) si applica dalla Fase {schema_linking_phase} "
            f"({wf.phase_name(schema_linking_phase)}). Niente da verificare ora: "
            "prosegui con lo schema linking.",
            fg=typer.colors.CYAN,
        )
        return
    problems = session_problems(cfg, session_id)
    if problems:
        typer.secho(f"Sessione {session_id} incompleta:", fg=typer.colors.YELLOW)
        for p in problems:
            typer.echo(f"  - {p}")
        raise typer.Exit(code=3)
    typer.secho(f"OK: sessione {session_id} completa per il Blocco 3.", fg=typer.colors.GREEN)


ARTIFACT_FILES = [
    "session_manifest.yaml", "question.md", "schema_linking.json", "evidence.json",
    "cte_tests.json", "sql_final.sql", "validation_report.md", "review_decisions.jsonl",
]


@session_app.command("finalize")
def finalize_cmd(session_id: str = typer.Argument(...), config: Path = CONFIG_OPT) -> None:
    """Gate finale + batteria di validazione + artefatto di sessione completo."""
    import json

    from tht.cli.sql_cmd import (
        _load_physical_or_exit,
        do_explain,
        do_run,
        promoted_tables_for,
    )
    from tht.ctetest import CteError, load_cte_tests
    from tht.execute import ExecutionError
    from tht.execute.warnings import plan_warnings, runtime_warnings, static_warnings
    from tht.report import extract_reviewer_notes, render_validation_report
    from tht.session.artifacts import build_evidence_entries
    from tht.phase import cte_plan as effective_cte_plan
    from tht.phase import effective_decisions
    from tht.session.models import SchemaLinking
    from tht.sqlcheck import validate_sql

    cfg = _load_config_or_exit(config)
    manifest = load_session_or_exit(cfg, session_id)
    sdir = session_dir(cfg, session_id)

    from tht.phase import current_phase
    from tht.workflow import load_workflow

    cur = current_phase(sdir)
    wf = load_workflow()
    if cur <= wf.max_phase:
        typer.secho(
            f"Finalize rifiutato: workflow non completo, sei in Fase {cur} "
            f"({wf.phase_name(min(cur, wf.max_phase))}). Tutte le {wf.max_phase} fasi "
            "devono essere approvate (anche dopo eventuali reopen).",
            fg=typer.colors.YELLOW, err=True,
        )
        raise typer.Exit(code=5)

    # --- gate di ingresso ---
    # Vista effective (D15): un sql_approved/cte ritirato o stale post-rollback non conta.
    problems = session_problems(cfg, session_id)
    decisions = effective_decisions(sdir)
    sql_file = sdir / "sql_final.sql"
    if not sql_file.exists():
        problems.append("sql_final.sql assente")
    if not any(d.type == "sql_approved" for d in decisions):
        problems.append(
            "decisione sql_approved assente: la validazione semantica del reviewer "
            "e' obbligatoria prima del finalize"
        )
    # I CTE richiesti sono quelli del PIANO effettivo, non i file glob su disco: un
    # ctes/*.sql orfano lasciato da un teardown incompleto non deve bloccare il finalize.
    plan = effective_cte_plan(sdir)
    if plan:
        try:
            tested = {r.name for r in load_cte_tests(sdir)}
        except CteError as e:
            typer.secho(
                f"Finalize rifiutato: impossibile leggere cte_tests.json: {e}",
                fg=typer.colors.RED, err=True,
            )
            raise typer.Exit(code=3)
        for name in plan:
            if name not in tested:
                problems.append(f"CTE mai testato: {name}")
    if problems:
        typer.secho(f"Finalize rifiutato per {session_id}:", fg=typer.colors.YELLOW)
        for p in problems:
            typer.echo(f"  - {p}")
        raise typer.Exit(code=3)

    # --- batteria di validazione su sql_final.sql ---
    sql = sql_file.read_text()
    check = validate_sql(
        sql,
        physical=_load_physical_or_exit(cfg),
        promoted_tables=promoted_tables_for(cfg, session_id),
        forbidden_functions=set(cfg.execution.forbidden_functions),
    )
    if not check.ok:
        typer.secho("Finalize rifiutato: sql_final.sql non passa la validazione statica:",
                    fg=typer.colors.RED, err=True)
        for e in check.errors:
            typer.echo(f"  - {e}", err=True)
        raise typer.Exit(code=3)
    limit = cfg.execution.max_preview_rows
    try:
        plan = do_explain(cfg, sql)
        result = do_run(cfg, sql, limit=limit)
    except ExecutionError as e:
        typer.secho(f"Finalize rifiutato: {e}", fg=typer.colors.RED, err=True)
        raise typer.Exit(code=3)

    # --- validation_report.md (preservando le note del reviewer) ---
    report_path = sdir / "validation_report.md"
    existing_notes = (
        extract_reviewer_notes(report_path.read_text()) if report_path.exists() else ""
    )
    report_path.write_text(render_validation_report(
        session_id=session_id, check=check, plan=plan,
        plan_warnings=plan_warnings(plan, cfg.execution),
        result=result, runtime_warnings=runtime_warnings(result, cfg.execution),
        static_warnings=static_warnings(check.ast), limit=limit,
        reviewer_notes=existing_notes,
    ))

    # --- evidence.json ---
    linking = SchemaLinking.model_validate(
        json.loads((sdir / "schema_linking.json").read_text())
    )
    entries = build_evidence_entries(decisions, linking, cfg.paths.artifacts / "evidence")
    (sdir / "evidence.json").write_text(json.dumps(entries, ensure_ascii=False, indent=2))

    # --- manifest + riepilogo ---
    from datetime import UTC, datetime

    from tht.session.store import MANIFEST, current_author

    manifest.status = "finalized"
    manifest.updated_at = datetime.now(UTC)
    manifest.updated_by = current_author()
    manifest.to_yaml(sdir / MANIFEST)
    typer.secho(f"OK: sessione {session_id} finalizzata. Artefatti:", fg=typer.colors.GREEN)
    for name in ARTIFACT_FILES:
        state = "presente" if (sdir / name).exists() else "assente"
        typer.echo(f"  - {name}: {state}")