from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware
from pydantic import BaseModel
from typing import Optional
import re
import json
import os
from datetime import datetime

COMPOSE_FILE = "docker-compose.yml"
JSON_FILE = "compose_changes.json"



app = FastAPI()

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_methods=["*"],
    allow_headers=["*"],
)

class ComposeConfig(BaseModel):
    icesecretwrite: Optional[str] = None
    icesecretread:  Optional[str] = None
    dbDriver:       Optional[str] = None
    dbHost:         Optional[str] = None
    dbPort:         Optional[str] = None
    database:       Optional[str] = None
    dbUsername:     Optional[str] = None
    dbPassword:     Optional[str] = None



def read_json():
    if not os.path.exists(JSON_FILE):
        return {"file": "docker-compose.yml", "version": 0}
    with open(JSON_FILE) as f:
        return json.load(f)



def write_json(changes):
    data = read_json()
    data["version"] += 1
    data["last_updated"] = datetime.now().isoformat()
    with open(JSON_FILE, "w") as f:
        json.dump(data, f, indent=2)
    return data["version"]

def update_compose(
    icesecretwrite=None,
    icesecretread=None,
    dbDriver=None,
    dbHost=None,
    dbPort=None,
    database=None,
    dbUsername=None,
    dbPassword=None
):
    with open(COMPOSE_FILE, "r") as f:
        content = f.read()

    changes = {
        "MUMBLE_CONFIG_icesecretwrite": icesecretwrite,
        "MUMBLE_CONFIG_icesecretread":  icesecretread,
        "MUMBLE_CONFIG_dbDriver":       dbDriver,
        "MUMBLE_CONFIG_dbHost":         dbHost,
        "MUMBLE_CONFIG_dbPort":         dbPort,
        "MUMBLE_CONFIG_database":       database,
        "MUMBLE_CONFIG_dbUsername":     dbUsername,
        "MUMBLE_CONFIG_dbPassword":     dbPassword,
    }

    for key, value in changes.items():
        if value is None:
            continue  # skip fields not passed in
        # replace the value after the = sign
        content = re.sub(
            rf"({key}=).*",
            rf"\g<1>{value}",
            content
        )

    with open(COMPOSE_FILE, "w") as f:
        f.write(content)
    version = write_json(changes)
    print(f"[✓] docker-compose.yml updated")

# --- usage ---
# update_compose(
#     dbHost="172.test.test.test",
#     dbPassword="testpassword",
#     dbPort="5437test"
# )

@app.post("/update")
def update(config: ComposeConfig):
    changes = config.model_dump()

    # check at least one field provided
    if not any(v is not None for v in changes.values()):
        return {"error": "No fields provided — nothing to update"}
    print(changes)
    updated = update_compose(icesecretwrite=changes["icesecretwrite"],
    icesecretread=changes["icesecretread"],
    dbDriver=changes["dbDriver"],
    dbHost=changes["dbHost"],
    dbPort=changes["dbPort"],
    database=changes["database"],
    dbUsername=changes["dbUsername"],
    dbPassword=changes["dbPassword"])
    version = write_json(updated)

    return {
        "message": "docker-compose.yml updated"
    }