"""
PHI-Arc Engine PHM — Turbojet Engine Model
Reference: J85/GE-15 class military turbojet
Certification: MIL-E-5007D, FAR Part 33
"""
import numpy as np
from typing import Dict, List
from .base_engine import BaseEngine

GAMMA_C = 1.40
CP_C = 1005.0
GAMMA_H = 1.333
CP_H = 1148.0
P_SL = 101325.0
T_ISA_SL = 288.15
LAPSE = 0.0065
LHV_JP8 = 43.24e6

class TurbojetEngine(BaseEngine):
    def __init__(self):
        super().__init__(
            name="J85-GE Class Turbojet",
            engine_type="turbojet",
            ata_chapters={
                "72-00": "Engine General",
                "72-30": "Compressor",
                "72-50": "Turbine",
                "73-10": "Fuel System",
                "75-30": "Bleed Air",
                "77-10": "Engine Controls"
            }
        )
        self._build_fault_library()
        self.cert_standards = [
            "MIL-E-5007D — General Specification for Aircraft Turbojet Engines",
            "FAR Part 33 — Airworthiness Standards",
            "MIL-STD-810 — Environmental Engineering Considerations",
            "JSSG-2007B — Engine Subsystem Specification"
        ]

        self.OPR = 8.0
        self.eta_c = 0.82
        self.eta_t = 0.87
        self.eta_b = 0.995
        self.eta_mech = 0.98
        self.mdot = 20.0
        self.EGT_REDLINE = 1050.0
        self.EGT_WARN = 1000.0

    def _build_fault_library(self):
        self.fault_library = [
            {
                "id": "F1", "name": "F1 — Compressor Surge / Stall", "ata": "ATA 72-30",
                "mechanism": "Axial compressor blade stall causes flow separation and pressure drop. EGT spikes, N1 fluctuates. Potential for engine flameout.",
                "leading": "N1 fluctuation + EGT spike + P3 drop (surge signature)", "color": "#e74c3c",
                "levels": [[0.98,1.00,1.00,0.00],[0.94,1.00,1.00,0.00],[0.90,1.00,1.00,0.00]],
                "actions": [
                    "Compressor borescope + blade inspection (AMM 72-30-00-200-801)",
                    "Bleed valve / surge recovery system test (AMM 75-30-00-040-801)",
                    "Compressor replacement (AMM 72-30-00-720-801)"
                ],
                "cert_requirements": [
                    "MIL-E-5007D 3.2.1.1 — Compressor stall margin ≥ 10%",
                    "FAR 33.65 — Surge and stall characteristics",
                    "JSSG-2007B 4.1.2 — Stall recovery within 5 seconds"
                ]
            },
            {
                "id": "F2", "name": "F2 — Turbine Blade Overtemp / Creep", "ata": "ATA 72-50",
                "mechanism": "Prolonged high EGT operation causes turbine blade creep and coating degradation. Blade tip clearance increases, efficiency drops.",
                "leading": "EGT↑↑ with N1 stable (turbine degradation)", "color": "#f39c12",
                "levels": [[1.00,0.99,1.00,0.00],[1.00,0.96,1.00,0.00],[1.00,0.93,1.00,0.00]],
                "actions": [
                    "Hot section borescope (AMM 72-50-00-200-801)",
                    "Turbine blade coating repair (AMM 72-50-00-400-801)",
                    "Turbine module replacement (AMM 72-50-00-720-801)"
                ],
                "cert_requirements": [
                    "MIL-E-5007D 3.2.2.1 — Turbine blade life ≥ declared cycles",
                    "FAR 33.27 — Turbine operating temperature limits",
                    "JSSG-2007B 4.2.1 — Creep life tracking required"
                ]
            },
            {
                "id": "F3", "name": "F3 — Afterburner Fuel System Fault", "ata": "ATA 73-10 / 75-40",
                "mechanism": "Afterburner fuel manifold leak or nozzle blockage causes asymmetric combustion. Thrust loss, EGT spread, potential for burner can damage.",
                "leading": "Thrust↓ + EGT spread↑ + AB fuel pressure↓", "color": "#9b59b6",
                "levels": [[0.99,1.00,1.00,0.00],[0.97,1.00,1.00,0.00],[0.95,1.00,1.00,0.00]],
                "actions": [
                    "Afterburner fuel nozzle flow test (AMM 73-10-00-200-801)",
                    "AB fuel manifold pressure test + repair (AMM 73-10-00-400-801)",
                    "Afterburner module replacement (AMM 75-40-00-720-801)"
                ],
                "cert_requirements": [
                    "MIL-E-5007D 3.2.3.1 — Afterburner fuel distribution tolerance",
                    "FAR 33.33 — Fuel system integrity",
                    "JSSG-2007B 4.3.1 — Afterburner pattern factor ≤ 0.30"
                ]
            },
            {
                "id": "F4", "name": "F4 — Nozzle Area Degradation", "ata": "ATA 75-40",
                "mechanism": "Thermal erosion of convergent-divergent nozzle throat increases area. Back pressure drops, N1 increases to maintain thrust, EGT may drop.",
                "leading": "N1↑ + EGT↓ + thrust↓ (nozzle area↑)", "color": "#3498db",
                "levels": [[1.00,1.00,0.99,0.00],[1.00,1.00,0.97,0.00],[1.00,1.00,0.94,0.00]],
                "actions": [
                    "Nozzle throat dimension inspection (AMM 75-40-00-200-801)",
                    "Nozzle segment replacement (AMM 75-40-00-400-801)",
                    "Full nozzle assembly replacement (AMM 75-40-00-720-801)"
                ],
                "cert_requirements": [
                    "MIL-E-5007D 3.2.4.1 — Nozzle area tolerance ±2%",
                    "FAR 33.5 — Engine ratings and operating limitations",
                    "JSSG-2007B 4.4.1 — Nozzle throat erosion limits"
                ]
            },
            {
                "id": "F5", "name": "F5 — Bearing / Lubrication System", "ata": "ATA 79-20",
                "mechanism": "Main shaft bearing wear increases vibration and oil temperature. Metal particles in oil. Potential for catastrophic failure if undetected.",
                "leading": "Oil temp↑ + vibration↑ + metal particles↑ (SOAP)", "color": "#1abc9c",
                "levels": [[1.00,1.00,1.00,0.020],[1.00,1.00,1.00,0.040],[1.00,1.00,1.00,0.065]],
                "actions": [
                    "Oil SOAP + vibration analysis (AMM 79-20-00-200-801)",
                    "Bearing replacement (AMM 72-00-00-400-801)",
                    "Engine removal + overhaul (AMM 72-00-00-720-801)"
                ],
                "cert_requirements": [
                    "MIL-E-5007D 3.2.5.1 — Bearing life ≥ declared cycles",
                    "FAR 33.62 — Oil system integrity",
                    "MIL-PRF-23699 — Oil contamination limits"
                ]
            }
        ]

    def isa_conditions(self, alt_m):
        T = T_ISA_SL - LAPSE * alt_m
        P = P_SL * (T / T_ISA_SL) ** 5.2561
        return T, P

    def compute_healthy_baseline(self, flight_conditions: Dict) -> Dict[str, float]:
        alt_m = flight_conditions.get("altitude_m", 0)
        M = flight_conditions.get("mach", 0.0)
        thrust = flight_conditions.get("thrust_n", 15000)

        T, P = self.isa_conditions(alt_m)
        T_t2 = T * (1 + 0.2 * M * M)
        P_t2 = P * (T_t2 / T) ** 3.5

        T_t3 = T_t2 * (1 + (self.OPR**0.2857 - 1) / self.eta_c)
        P_t3 = P_t2 * self.OPR

        mdot = self.mdot * (P_t2 / P_SL) * (T_ISA_SL / T_t2)**0.5
        W_comp = mdot * CP_C * (T_t3 - T_t2)
        W_req = W_comp + thrust / self.eta_mech

        TIT = T_t3 + W_req / (mdot * CP_H * 0.35)
        T_t5 = TIT * (1 - self.eta_t * 0.35)
        EGT = T_t5 - 273.15
        FF = mdot * CP_H * (TIT - T_t3) / (self.eta_b * LHV_JP8)
        N1 = (mdot / self.mdot)**0.5 * (self.OPR/8)**0.25 * 100
        P3 = P_t3 / 1000

        return {"EGT": EGT, "FF": FF, "N1": N1, "P3": P3, "TIT": TIT, "T_amb": T, "P_amb": P}

    def compute_fault_signatures(self, baseline: Dict, flight_conditions: Dict) -> List[List[Dict]]:
        results = []
        for f in self.fault_library:
            lvl_vals = []
            for lv in range(3):
                m = f["levels"][lv]
                alt_m = flight_conditions.get("altitude_m", 0)
                M = flight_conditions.get("mach", 0.0)
                thrust = flight_conditions.get("thrust_n", 15000)

                T, P = self.isa_conditions(alt_m)
                T_t2 = T * (1 + 0.2 * M * M)
                P_t2 = P * (T_t2 / T) ** 3.5

                eta_c = self.eta_c * m[0]
                eta_t = self.eta_t * m[1]
                eta_b = self.eta_b * m[2]
                mech_loss = m[3]

                T_t3 = T_t2 * (1 + (self.OPR**0.2857 - 1) / eta_c)
                P_t3 = P_t2 * self.OPR
                mdot = self.mdot * (P_t2 / P_SL) * (T_ISA_SL / T_t2)**0.5
                W_comp = mdot * CP_C * (T_t3 - T_t2)
                W_req = W_comp + thrust / (self.eta_mech - mech_loss)
                TIT = T_t3 + W_req / (mdot * CP_H * 0.35)
                T_t5 = TIT * (1 - eta_t * 0.35)
                EGT = T_t5 - 273.15
                FF = mdot * CP_H * (TIT - T_t3) / (eta_b * LHV_JP8)
                N1 = (mdot / self.mdot)**0.5 * (self.OPR/8)**0.25 * 100
                P3 = P_t3 / 1000

                lvl_vals.append({"EGT": EGT, "FF": FF, "N1": N1, "P3": P3})
            results.append(lvl_vals)
        return results

    def classify_fault(self, measured: Dict, baseline: Dict, fault_sigs: List[List[Dict]]) -> Dict:
        params = ["EGT", "FF", "N1", "P3"]
        user_sig = np.zeros(4)
        for i, p in enumerate(params):
            if p in measured and p in baseline:
                denom = baseline[p] * 0.05 if p == "N1" else (baseline[p] * 0.10 if p == "FF" else (self.EGT_REDLINE - baseline[p] if p == "EGT" else baseline[p] * 0.10))
                user_sig[i] = (measured[p] - baseline[p]) / denom if denom != 0 else 0

        scores = []
        for fi, f in enumerate(self.fault_library):
            best_score = -1e9
            best_lvl = 0
            for lv in range(3):
                fv = fault_sigs[fi][lv]
                sig = np.zeros(4)
                for i, p in enumerate(params):
                    denom = baseline[p] * 0.05 if p == "N1" else (baseline[p] * 0.10 if p == "FF" else (self.EGT_REDLINE - baseline[p] if p == "EGT" else baseline[p] * 0.10))
                    sig[i] = (fv[p] - baseline[p]) / denom if denom != 0 else 0
                denom = (np.linalg.norm(sig) * np.linalg.norm(user_sig)) + 1e-9
                score = np.dot(sig, user_sig) / denom
                if score > best_score:
                    best_score = score
                    best_lvl = lv
            sev = max(0.0, min(1.0, best_score))
            scores.append({"fi": fi, "f": f, "sev": sev, "lvl": best_lvl, "sig": user_sig})

        scores.sort(key=lambda x: x["sev"], reverse=True)
        magnitude = np.linalg.norm(user_sig)

        status = "HEALTHY" if magnitude < 0.12 else ("INDETERMINATE" if scores[0]["sev"] < 0.30 else "FAULT_DETECTED")

        return {
            "base": baseline, "faults": fault_sigs, "scores": scores,
            "user_sig": user_sig, "status": status,
            "thresholds": {
                "EGT_warn": self.EGT_WARN, "EGT_maint": self.EGT_REDLINE,
                "FF_warn": baseline["FF"] * 1.03, "FF_maint": baseline["FF"] * 1.06,
                "N1_warn": baseline["N1"] * 0.985, "N1_maint": baseline["N1"] * 0.970
            },
            "deviations": {p: user_sig[i] for i, p in enumerate(params)}
        }

    def get_parameter_labels(self) -> List[str]:
        return ["EGT", "Fuel Flow", "N1", "P3"]

    def get_parameter_units(self) -> Dict[str, str]:
        return {"EGT": "°C", "FF": "kg/s", "N1": "%", "P3": "kPa"}

    def get_input_fields(self) -> List[Dict]:
        return [
            {"name": "altitude", "label": "Altitude", "default": 0, "unit": "ft", "type": "number"},
            {"name": "mach", "label": "Mach Number", "default": 0.0, "unit": "Mach", "type": "number"},
            {"name": "thrust", "label": "Thrust Setting", "default": 15, "unit": "kN", "type": "number"},
            {"name": "EGT", "label": "EGT", "default": 650.0, "unit": "°C", "type": "number"},
            {"name": "FF", "label": "Fuel Flow", "default": 1200.0, "unit": "kg/hr", "type": "number"},
            {"name": "N1", "label": "N1 Speed", "default": 100.0, "unit": "%", "type": "number"},
            {"name": "P3", "label": "Compressor Discharge Pressure", "default": 450.0, "unit": "kPa", "type": "number"}
        ]