"""Google Sheets integration — exports RACI and Risk Register as shareable spreadsheets."""

import asyncio
import os

from core.planner import ERROR_MESSAGES, ProjectPlan, RACIEntry

SCOPES = ["https://www.googleapis.com/auth/spreadsheets"]


def _build_service():
    """Build Google Sheets API service. Return None if credentials unavailable."""
    try:
        from google.oauth2.credentials import Credentials
        from googleapiclient.discovery import build
    except ImportError:
        return None

    client_id = os.environ.get("GOOGLE_CLIENT_ID")
    client_secret = os.environ.get("GOOGLE_CLIENT_SECRET")
    if not client_id or not client_secret:
        return None

    try:
        credentials = Credentials(
            token=None,
            client_id=client_id,
            client_secret=client_secret,
            scopes=SCOPES,
        )
        return build("sheets", "v4", credentials=credentials)
    except Exception:
        return None


def _raci_rows(plan: ProjectPlan) -> list[list]:
    """Build rows for RACI sheet using plan.raci entries."""
    # Collect all unique teams in order of appearance
    teams: list[str] = []
    for entry in plan.raci:
        for team in (entry.responsible + [entry.accountable] + entry.consulted + entry.informed):
            if team and team not in teams:
                teams.append(team)

    header = ["Task"] + teams
    rows = [header]
    for entry in plan.raci:
        row = [entry.task]
        for team in teams:
            roles: list[str] = []
            if team in entry.responsible:
                roles.append("R")
            if team == entry.accountable:
                roles.append("A")
            if team in entry.consulted:
                roles.append("C")
            if team in entry.informed:
                roles.append("I")
            row.append("/".join(roles) if roles else "")
        rows.append(row)
    return rows


def _risks_rows(plan: ProjectPlan) -> list[list]:
    """Build rows for Risk Register using plan.risks entries."""
    header = ["Phase", "Description", "Likelihood", "Impact", "Mitigation"]
    rows = [header]
    for risk in plan.risks:
        rows.append([
            risk.phase_id or "General",
            risk.description,
            risk.likelihood,
            risk.impact,
            risk.mitigation,
        ])
    return rows


async def export_raci(plan: ProjectPlan) -> dict:
    """
    Create a new Google Spreadsheet with RACI data.
    Returns {"success": bool, "url": str | None, "error": str | None}
    """
    service = _build_service()
    if service is None:
        return {"success": False, "url": None, "error": ERROR_MESSAGES["google_auth"]}

    try:
        rows = _raci_rows(plan)

        def _create() -> str:
            body = {"properties": {"title": "ProjectCraft — RACI Matrix"}}
            spreadsheet = service.spreadsheets().create(body=body, fields="spreadsheetId").execute()
            sheet_id = spreadsheet["spreadsheetId"]
            service.spreadsheets().values().update(
                spreadsheetId=sheet_id,
                range="Sheet1!A1",
                valueInputOption="RAW",
                body={"values": rows},
            ).execute()
            return f"https://docs.google.com/spreadsheets/d/{sheet_id}"

        url = await asyncio.to_thread(_create)
        return {"success": True, "url": url, "error": None}

    except Exception as exc:
        return {"success": False, "url": None, "error": str(exc)}


async def export_risks(plan: ProjectPlan) -> dict:
    """
    Create a new Google Spreadsheet with Risk Register data.
    Returns {"success": bool, "url": str | None, "error": str | None}
    """
    service = _build_service()
    if service is None:
        return {"success": False, "url": None, "error": ERROR_MESSAGES["google_auth"]}

    try:
        rows = _risks_rows(plan)

        def _create() -> str:
            body = {"properties": {"title": "ProjectCraft — Risk Register"}}
            spreadsheet = service.spreadsheets().create(body=body, fields="spreadsheetId").execute()
            sheet_id = spreadsheet["spreadsheetId"]
            service.spreadsheets().values().update(
                spreadsheetId=sheet_id,
                range="Sheet1!A1",
                valueInputOption="RAW",
                body={"values": rows},
            ).execute()
            return f"https://docs.google.com/spreadsheets/d/{sheet_id}"

        url = await asyncio.to_thread(_create)
        return {"success": True, "url": url, "error": None}

    except Exception as exc:
        return {"success": False, "url": None, "error": str(exc)}