from __future__ import annotations

from typing import Dict, List, Literal, Optional, Union
from pydantic import BaseModel, ConfigDict, Field


# -------------------------
# HIL blocks (v1.3)
# -------------------------

class TankLevelBlock(BaseModel):
    model_config = ConfigDict(extra="forbid")
    type: Literal["tank_level"] = "tank_level"

    level_out: str
    inlet_cmd: str
    outlet_cmd: str

    dt: float = 0.1
    area: float = 1.0
    max_level: float = 1.0
    inflow_rate: float = 0.25
    outflow_rate: float = 0.25
    leak_rate: float = 0.0

    initial_level: Optional[float] = None


class BottleLineBlock(BaseModel):
    """
    Minimal bottle + conveyor dynamics (Strada A):
    - bottle_at_filler_out = 1 when conveyor_cmd <= 0.5 else 0
    - bottle_fill_level_out increases when at_filler==1
    - bottle_fill_level_out decreases slowly when conveyor ON (new/empty bottle coming)
    """
    model_config = ConfigDict(extra="forbid")
    type: Literal["bottle_line"] = "bottle_line"

    conveyor_cmd: str
    bottle_at_filler_out: str
    bottle_fill_level_out: str

    dt: float = 0.1
    fill_rate: float = 0.25      # per second
    drain_rate: float = 0.40     # per second when conveyor ON (reset toward 0)
    initial_fill: float = 0.0


HILBlock = Union[TankLevelBlock, BottleLineBlock]


class IRHIL(BaseModel):
    model_config = ConfigDict(extra="forbid")
    name: str
    logic: str

    outputs_init: Dict[str, float] = Field(default_factory=dict)
    blocks: List[HILBlock] = Field(default_factory=list)


# -------------------------
# PLC rules (v1.2)
# -------------------------

class HysteresisFillRule(BaseModel):
    model_config = ConfigDict(extra="forbid")
    type: Literal["hysteresis_fill"] = "hysteresis_fill"

    level_in: str
    low: float = 0.2
    high: float = 0.8

    inlet_out: str
    outlet_out: str

    enable_input: Optional[str] = None

    # Signal range for converting normalized thresholds to absolute values
    # If signal_max=1000, then low=0.2 becomes 200, high=0.8 becomes 800
    signal_max: float = 1.0  # Default 1.0 means thresholds are already absolute


class ThresholdOutputRule(BaseModel):
    model_config = ConfigDict(extra="forbid")
    type: Literal["threshold_output"] = "threshold_output"

    input_id: str
    threshold: float = 0.2
    op: Literal["lt"] = "lt"

    output_id: str
    true_value: int = 1
    false_value: int = 0

    # Signal range for converting normalized threshold to absolute value
    # If signal_max=200, then threshold=0.2 becomes 40
    signal_max: float = 1.0  # Default 1.0 means threshold is already absolute


PLCRule = Union[HysteresisFillRule, ThresholdOutputRule]


class IRPLC(BaseModel):
    model_config = ConfigDict(extra="forbid")
    name: str
    logic: str

    rules: List[PLCRule] = Field(default_factory=list)


class IRSpec(BaseModel):
    model_config = ConfigDict(extra="forbid")
    version: Literal["ir_v1"] = "ir_v1"
    plcs: List[IRPLC] = Field(default_factory=list)
    hils: List[IRHIL] = Field(default_factory=list)