"""
Validator v4 training data builder — augments v3 data with semantic-error negatives.

Problem: v3 validators have ~5.8% flagging rate on exec_ok=True wrong SQL.
Fix: add exec_ok=True wrong trajectories as negatives with heuristic critiques.

Output format: same as v3 (select/condition sections) for pipeline compatibility.
"""
import json, os, re, random, sqlite3, threading
from datasets import load_from_disk, Dataset, DatasetDict

ROOT = "/weka/s225250685/mats-tist"
os.chdir(ROOT)

SRC_PATHS = [
    "data/rollouts/scaleup_bird_train_2stage_K4.jsonl",
    "data/rollouts/bird_train_3stage_K4.jsonl",
    "data/rollouts/iter2_bird_train_3stage_K8.jsonl",
]

V3_DATA = "data/sft-validator-selection-v3"   # existing v3 data (sel)
V3_COND = "data/sft-validator-condition-v3"   # existing v3 data (cond)
OUT_SEL  = "data/hf_validator_v4_sel"
OUT_COND = "data/hf_validator_v4_cond"

SEL_INSTR  = ("You are a SQL SELECT-clause critique agent. Output ONE critique section "
              "<select>...</select> analysing the SELECT clause of the SQL query below; "
              "do NOT output any SQL. Use 'None' if the SELECT clause looks correct.")
COND_INSTR = ("You are a SQL CONDITION critique agent. Output ONE critique section "
              "<condition>...</condition> analysing the WHERE/HAVING/CASE-WHEN conditions "
              "of the SQL query below; do NOT output any SQL. Use 'None' if the conditions look correct.")


def resolve_db_path(d):
    db_path = d.get("db_path", "")
    if db_path and os.path.exists(db_path):
        return db_path
    db_id = d.get("db_id", "")
    for tmpl in [
        f"data/train_databases/{db_id}/{db_id}.sqlite",
        f"data/dev_databases/{db_id}/{db_id}.sqlite",
    ]:
        if os.path.exists(tmpl):
            return tmpl
    return None


def exec_sql(db_path, sql, timeout=5):
    result = [None]; error = [None]
    def _run():
        try:
            conn = sqlite3.connect(db_path)
            conn.text_factory = lambda b: b.decode(errors="ignore")
            result[0] = conn.execute(sql).fetchmany(5)
            conn.close()
        except Exception as e:
            error[0] = str(e)
    t = threading.Thread(target=_run, daemon=True)
    t.start(); t.join(timeout)
    if t.is_alive():
        return None, "TIMEOUT"
    return result[0], error[0]


def generate_select_critique(wrong_sql, gold_sql):
    """Generate specific SELECT critique. Top errors from analysis:
    DISTINCT mismatch (25.7%), aggregation mismatch (25.5%), subquery diff (12%)."""
    wl, gl = wrong_sql.lower(), gold_sql.lower()
    issues = []
    for agg in ["count(", "sum(", "avg(", "max(", "min("]:
        if agg in gl and agg not in wl:
            issues.append(f"Missing {agg[:-1].upper()} in SELECT")
        elif agg in wl and agg not in gl:
            issues.append(f"Unexpected {agg[:-1].upper()} in SELECT")
    if "distinct" in gl and "distinct" not in wl:
        issues.append("Missing DISTINCT — query returns duplicate rows")
    elif "distinct" in wl and "distinct" not in gl:
        issues.append("Unexpected DISTINCT — query incorrectly deduplicates")
    # Subquery difference
    gs, ws = gl.count("select") - 1, wl.count("select") - 1
    if gs > ws:
        issues.append(f"Missing subquery (gold has {gs}, wrong has {ws})")
    elif ws > gs:
        issues.append(f"Unexpected subquery (gold has {gs}, wrong has {ws})")
    if issues:
        detail = "INCORRECT: " + "; ".join(issues) + "."
    else:
        detail = "INCORRECT: SELECT clause returns wrong results for this question."
    return f"<select>\nSELECT.\n{detail}\n</select>"


def generate_condition_critique(wrong_sql, gold_sql):
    """Generate specific CONDITION critique. Top errors: JOIN mismatch (30%),
    GROUP BY (6.9%), ORDER BY (8.3%), LIMIT (7.8%), subtle conditions (30.6%)."""
    wl, gl = wrong_sql.lower(), gold_sql.lower()
    issues = []
    # JOIN count
    gj, wj = gl.count("join"), wl.count("join")
    if gj > wj:
        issues.append(f"Missing JOIN (gold has {gj}, wrong has {wj})")
    elif wj > gj:
        issues.append(f"Extra JOIN (gold has {gj}, wrong has {wj})")
    if "group by" in gl and "group by" not in wl:
        issues.append("Missing GROUP BY clause")
    elif "group by" in wl and "group by" not in gl:
        issues.append("Unexpected GROUP BY clause")
    if "having" in gl and "having" not in wl:
        issues.append("Missing HAVING clause")
    if ("order by" in gl) != ("order by" in wl):
        issues.append("ORDER BY mismatch")
    if ("limit" in gl) != ("limit" in wl):
        issues.append("LIMIT clause mismatch")
    if issues:
        detail = "INCORRECT: " + "; ".join(issues) + "."
    else:
        detail = "INCORRECT: WHERE/HAVING conditions return wrong results for this question."
    return f"<condition>\nCONDITION.\n{detail}\n</condition>"


NONE_SEL  = "<select>\nSELECT.\nNone\n</select>"
NONE_COND = "<condition>\nCONDITION.\nNone\n</condition>"


def build_prompt(instr, schema, question, evidence, sql, exec_str):
    # Field labels must match run_pipeline_rollouts.py VALIDATOR_PROMPT_BODY exactly.
    body = (f"database schema:\n{schema}\n\nQuestion: {question}\n"
            f"External knowledge: {evidence or 'None'}\n\nGenerated SQL query: {sql}\n\nExecution response:\n{exec_str}\n\n")
    return instr + "\n\n" + body


def make_row(instr, schema, question, evidence, sql, exec_str, completion):
    prompt = build_prompt(instr, schema, question, evidence, sql, exec_str)
    # "chosen" key for train_fixer_v2.py compatibility; "completion" for legacy
    return {"prompt": prompt, "chosen": completion, "completion": completion,
            "messages": {"prompt": prompt, "completion": completion}}


def safe_trunc(s, n=3000):
    s = str(s or "")
    return s if len(s) <= n else s[:n] + "..."


def main():
    rng = random.Random(42)
    new_sel, new_cond = [], []
    seen = set()

    for src in SRC_PATHS:
        if not os.path.exists(src):
            print(f"skip {src}"); continue
        n_pos = n_neg = 0
        with open(src) as f:
            for line in f:
                line = line.strip()
                if not line: continue
                d = json.loads(line)
                db_path = resolve_db_path(d)
                if not db_path: continue
                schema   = safe_trunc(str(d.get("schema", "")), 2800)
                question = d.get("question", "")
                evidence = d.get("evidence", "") or "None"
                gold_sql = (d.get("sql") or "").strip()

                for t in d.get("trajectories", []):
                    sql = (t.get("planner_sql") or "").strip()
                    if not sql: continue
                    correct  = bool(t.get("is_planner_correct") or t.get("is_fixed_correct"))
                    exec_ok  = bool(t.get("planner_exec_ok", True))
                    key = (hash(question), sql[:60])
                    if key in seen: continue
                    seen.add(key)

                    rows, err = exec_sql(db_path, sql)
                    if rows is not None:
                        exec_str = "OK. Rows: " + str(rows)[:300]
                    elif err:
                        exec_str = "Error: " + err[:200]
                    else:
                        exec_str = "No result"

                    if correct and exec_ok:
                        # POSITIVE: SQL is correct
                        r_sel  = make_row(SEL_INSTR,  schema, question, evidence, sql, exec_str, NONE_SEL)
                        r_cond = make_row(COND_INSTR, schema, question, evidence, sql, exec_str, NONE_COND)
                        new_sel.append(r_sel)
                        new_cond.append(r_cond)
                        n_pos += 1

                    elif not correct and exec_ok and gold_sql:
                        # NEGATIVE: exec_ok=True but wrong — semantic error
                        sel_crit  = generate_select_critique(sql, gold_sql)
                        cond_crit = generate_condition_critique(sql, gold_sql)
                        r_sel  = make_row(SEL_INSTR,  schema, question, evidence, sql, exec_str, sel_crit)
                        r_cond = make_row(COND_INSTR, schema, question, evidence, sql, exec_str, cond_crit)
                        new_sel.append(r_sel)
                        new_cond.append(r_cond)
                        n_neg += 1

                    elif not exec_ok:
                        # NEGATIVE: exec error — clear signal
                        err_msg = exec_str[:200]
                        sel_crit  = f"<select>\nSELECT.\nSQL fails to execute: {err_msg}\n</select>"
                        cond_crit = f"<condition>\nCONDITION.\nSQL fails to execute: {err_msg}\n</condition>"
                        r_sel  = make_row(SEL_INSTR,  schema, question, evidence, sql, exec_str, sel_crit)
                        r_cond = make_row(COND_INSTR, schema, question, evidence, sql, exec_str, cond_crit)
                        new_sel.append(r_sel)
                        new_cond.append(r_cond)
                        n_neg += 1

        print(f"  {src}: +{n_pos} pos, +{n_neg} neg")

    print(f"\nNew rows — sel: {len(new_sel)}, cond: {len(new_cond)}")

    # Load existing v3 data and merge
    def load_v3(path):
        d = load_from_disk(path)
        rows = []
        for split in ["train", "test", "train_dpo", "test_dpo"]:
            if split in d:
                for ex in d[split]:
                    p, c = ex["prompt"], ex["completion"]
                    rows.append({"prompt": p, "chosen": c, "completion": c,
                                 "messages": {"prompt": p, "completion": c}})
        return rows

    v3_sel  = load_v3(V3_DATA)
    v3_cond = load_v3(V3_COND)
    print(f"V3 existing — sel: {len(v3_sel)}, cond: {len(v3_cond)}")

    combined_sel  = v3_sel + new_sel
    combined_cond = v3_cond + new_cond
    rng.shuffle(combined_sel)
    rng.shuffle(combined_cond)

    def split_and_save(rows, out_dir):
        n_test = max(200, len(rows) // 20)
        test, train = rows[:n_test], rows[n_test:]
        # Use train_dpo/test_dpo split names for train_fixer_v2.py compatibility
        DatasetDict({
            "train_dpo": Dataset.from_list(train),
            "test_dpo":  Dataset.from_list(test),
        }).save_to_disk(out_dir)
        print(f"  saved {len(train)} train_dpo + {len(test)} test_dpo → {out_dir}")

    split_and_save(combined_sel,  OUT_SEL)
    split_and_save(combined_cond, OUT_COND)
    print("DONE")


if __name__ == "__main__":
    main()