"""
Script 04 – Generate and export flight strings.

Reads the saved solution CSVs and generates a per-aircraft "flight string"
report in human-readable format (console + Excel export).
"""

import sys
from pathlib import Path

ROOT = Path(__file__).resolve().parents[1]
sys.path.insert(0, str(ROOT))

import pandas as pd

from src.routing_engine.config import DEFAULT_CONFIG

cfg = DEFAULT_CONFIG

sched_path = cfg.schedules_dir / "flight_strings.csv"
maint_path = cfg.schedules_dir / "maintenance_events.csv"

if not sched_path.exists():
    print("No schedule found. Run script 03 first.")
    sys.exit(1)

sched = pd.read_csv(sched_path, parse_dates=["departure", "arrival"])
maint = pd.read_csv(maint_path, parse_dates=["maint_start", "maint_end"]) if maint_path.exists() else pd.DataFrame()

print("=" * 70)
print("FLIGHT STRINGS PER AIRCRAFT")
print("=" * 70)

for aircraft, group in sched.groupby("aircraft"):
    print(f"\n{'-'*70}")
    print(f"  Aeronave: {aircraft}")
    print(f"{'-'*70}")

    total_fh = 0.0
    for _, row in group.sort_values("departure").iterrows():
        maint_flag = " <- MANUTENCAO ANTES" if row.get("maintenance_before") else ""
        dep = pd.to_datetime(row["departure"])
        arr = pd.to_datetime(row["arrival"])
        fh = float(row.get("flight_hours", 0))
        total_fh += fh
        print(
            f"    {row['ofrag_id']:12s}  "
            f"{dep.strftime('%d/%m %H:%M')} -> {arr.strftime('%d/%m %H:%M')}  "
            f"({fh:.2f} FH){maint_flag}"
        )

    print(f"    {'TOTAL':12s}  {total_fh:.2f} FH")

    if not maint.empty:
        ac_maint = maint[maint["aircraft"] == aircraft]
        if not ac_maint.empty:
            print(f"\n  Eventos de manutencao:")
            for _, ev in ac_maint.iterrows():
                print(
                    f"    CHECK (ciclo {int(ev['check_cycle_index'])})  "
                    f"{pd.to_datetime(ev['maint_start']).strftime('%d/%m %H:%M')} -> "
                    f"{pd.to_datetime(ev['maint_end']).strftime('%d/%m %H:%M')}  "
                    f"TTM perdido: {ev['ttm_loss_hours']:.2f} FH"
                )

# Export to Excel
out_xlsx = cfg.exports_dir / "flight_strings.xlsx"
try:
    with pd.ExcelWriter(out_xlsx, engine="openpyxl") as writer:
        sched.to_excel(writer, sheet_name="Escala", index=False)
        if not maint.empty:
            maint.to_excel(writer, sheet_name="Manutencao", index=False)
    print(f"\n\nExportado para Excel -> {out_xlsx}")
except ImportError:
    print("\n(openpyxl not installed – Excel export skipped)")