"""Machines plugin API endpoints."""

from flask import Blueprint, request
from flask_jwt_extended import jwt_required

from shopdb.api import db, Asset, AssetType, AuditLog, Vendor, success_response, error_response, paginated_response, ErrorCodes, get_pagination_params, paginate_query, resolve_dualpath_pairs, dualpath_single_machine_enabled

from ..models import Machine, MachineType

from shopdb.api import require_permission, apply_import_timestamps

machines_bp = Blueprint('machines', __name__)


# =============================================================================
# Machine Types
# =============================================================================

@machines_bp.route('/types', methods=['GET'])
@jwt_required(optional=True)
def list_machine_types():
    """List all machine types."""
    page, per_page = get_pagination_params(request)

    query = MachineType.query

    if request.args.get('active', 'true').lower() != 'false':
        query = query.filter(MachineType.isactive == True)

    if search := request.args.get('search'):
        query = query.filter(MachineType.machinetype.ilike(f'%{search}%'))

    query = query.order_by(MachineType.machinetype)

    items, total = paginate_query(query, page, per_page)
    data = [t.to_dict() for t in items]

    return paginated_response(data, page, per_page, total)


@machines_bp.route('/types/<int:type_id>', methods=['GET'])
@jwt_required(optional=True)
def get_machine_type(type_id: int):
    """Get a single machine type."""
    t = db.session.get(MachineType, type_id)

    if not t:
        return error_response(
            ErrorCodes.NOT_FOUND,
            f'Machine type with ID {type_id} not found',
            http_code=404
        )

    return success_response(t.to_dict())


@machines_bp.route('/types', methods=['POST'])
@jwt_required()
@require_permission('machines.create')
def create_machine_type():
    """Create a new machine type."""
    data = request.get_json()

    if not data or not data.get('machinetype'):
        return error_response(ErrorCodes.VALIDATION_ERROR, 'machinetype is required')

    existing = MachineType.query.filter_by(machinetype=data['machinetype']).first()
    if existing:
        if not existing.isactive:
            existing.isactive = True
            for key in ('description', 'icon', 'color'):
                if data.get(key) is not None:
                    setattr(existing, key, data[key])
            db.session.commit()
            return success_response(existing.to_dict(), message='Reactivated existing type')
        return error_response(
            ErrorCodes.CONFLICT,
            f"Machine type '{data['machinetype']}' already exists",
            http_code=409
        )

    t = MachineType(
        machinetype=data['machinetype'],
        description=data.get('description'),
        icon=data.get('icon'), color=data.get('color')
    )

    db.session.add(t)
    db.session.commit()

    return success_response(t.to_dict(), message='Machine type created', http_code=201)


@machines_bp.route('/types/<int:type_id>', methods=['PUT'])
@jwt_required()
@require_permission('machines.edit')
def update_machine_type(type_id: int):
    """Update a machine type."""
    t = db.session.get(MachineType, type_id)

    if not t:
        return error_response(
            ErrorCodes.NOT_FOUND,
            f'Machine type with ID {type_id} not found',
            http_code=404
        )

    data = request.get_json()
    if not data:
        return error_response(ErrorCodes.VALIDATION_ERROR, 'No data provided')

    if 'machinetype' in data and data['machinetype'] != t.machinetype:
        if MachineType.query.filter_by(machinetype=data['machinetype']).first():
            return error_response(
                ErrorCodes.CONFLICT,
                f"Machine type '{data['machinetype']}' already exists",
                http_code=409
            )

    for key in ['machinetype', 'description', 'icon', 'color', 'isactive']:
        if key in data:
            setattr(t, key, data[key])

    db.session.commit()
    return success_response(t.to_dict(), message='Machine type updated')


@machines_bp.route('/types/<int:type_id>', methods=['DELETE'])
@jwt_required()
@require_permission('machines.delete')
def delete_machine_type(type_id: int):
    """Delete a machine type. Refused if any asset still uses it."""
    t = db.session.get(MachineType, type_id)
    if not t:
        return error_response(ErrorCodes.NOT_FOUND, 'Machine type not found', http_code=404)
    inuse = Machine.query.filter_by(machinetypeid=type_id).count()
    if inuse:
        return error_response(ErrorCodes.CONFLICT,
                              f"Cannot delete: {inuse} asset(s) still use this type", http_code=409)
    db.session.delete(t)
    db.session.commit()
    return success_response(message='Machine type deleted')


# =============================================================================
# Machine CRUD
# =============================================================================

@machines_bp.route('', methods=['GET'])
@jwt_required(optional=True)
def list_machines():
    """
    List all machines with filtering and pagination.

    Query parameters:
    - page, per_page: Pagination
    - active: Filter by active status
    - search: Search by asset number or name
    - type_id: Filter by machine type ID
    - vendor_id: Filter by vendor ID
    - location_id: Filter by location ID
    - businessunit_id: Filter by business unit ID
    """
    page, per_page = get_pagination_params(request)

    # Join Machine with Asset
    query = db.session.query(Machine).join(Asset)

    # Active filter
    if request.args.get('active', 'true').lower() != 'false':
        query = query.filter(Asset.isactive == True)

    # Exact-match natural-key lookup for idempotent import (asset number).
    if exactassetnumber := request.args.get('assetnumber'):
        query = query.filter(Asset.assetnumber == exactassetnumber)

    # Search filter. Covers what the list actually SHOWS - the asset fields plus
    # the type and vendor names, which are columns in the table. Searching a type
    # like 'Part Washer' used to return nothing. Outer joins so a machine with no
    # type or vendor still matches on its own fields.
    if search := request.args.get('search'):
        pattern = f'%{search}%'
        query = query.outerjoin(
            MachineType, Machine.machinetypeid == MachineType.machinetypeid
        ).outerjoin(
            Vendor, Machine.vendorid == Vendor.vendorid
        ).filter(
            db.or_(
                Asset.assetnumber.ilike(pattern),
                Asset.name.ilike(pattern),
                Asset.serialnumber.ilike(pattern),
                # The optional identifiers too (ADR-001). Global search matches
                # these, and a tag read off the machine has to find it here as
                # well - this box is where someone holding the label looks.
                Asset.gaugelabreference.ilike(pattern),
                Asset.maintenancereference.ilike(pattern),
                MachineType.machinetype.ilike(pattern),
                Vendor.vendor.ilike(pattern)
            )
        )

    # Machine type filter
    if type_id := request.args.get('typeid', request.args.get('type_id')):
        query = query.filter(Machine.machinetypeid == int(type_id))

    # Vendor filter
    if vendor_id := request.args.get('vendorid', request.args.get('vendor_id')):
        query = query.filter(Machine.vendorid == int(vendor_id))

    # Location filter
    if location_id := request.args.get('locationid', request.args.get('location_id')):
        query = query.filter(Asset.locationid == int(location_id))

    # Business unit filter
    if bu_id := request.args.get('businessunitid', request.args.get('businessunit_id')):
        query = query.filter(Asset.businessunitid == int(bu_id))

    # Sorting
    sort_by = request.args.get('sort', 'assetnumber')
    sort_dir = request.args.get('dir', 'asc')

    if sort_by == 'assetnumber':
        col = Asset.assetnumber
    elif sort_by == 'name':
        col = Asset.name
    else:
        col = Asset.assetnumber

    query = query.order_by(col.desc() if sort_dir == 'desc' else col)

    # Dualpath single-machine collapse: hide the secondary bay so a dual-bay
    # pair lists (and paginates) as one machine. Excluding before pagination
    # keeps totals honest. Gated on the site setting (default on).
    collapse = None
    if dualpath_single_machine_enabled():
        collapse = resolve_dualpath_pairs()
        if collapse.secondaryassetids:
            query = query.filter(Asset.assetid.notin_(collapse.secondaryassetids))

    items, total = paginate_query(query, page, per_page)

    # Resolve partner machineids for this page's primaries in one query.
    machineidbyasset = {}
    if collapse:
        partnerassetids = [
            collapse.partnerbyasset[m.assetid]['assetid']
            for m in items if m.assetid in collapse.partnerbyasset
        ]
        if partnerassetids:
            for partner in Machine.query.filter(
                    Machine.assetid.in_(partnerassetids)).all():
                machineidbyasset[partner.assetid] = partner.machineid

    # Build response with both asset and machine data
    data = []
    for mach in items:
        item = mach.asset.to_dict() if mach.asset else {}
        item['machine'] = mach.to_dict()
        # annotate the visible bay with its hidden partner (for '2007 / 2008')
        partner = collapse.partnerbyasset.get(mach.assetid) if collapse else None
        item['dualpathpartner'] = {
            'assetid': partner['assetid'],
            'machineid': machineidbyasset.get(partner['assetid']),
            'assetnumber': partner['assetnumber'],
        } if partner else None
        data.append(item)

    return paginated_response(data, page, per_page, total)


def _dualpath_partner_for(assetid):
    """Resolve this machine's Dualpath sibling, or None. Always evaluated
    (independent of the collapse toggle) so the detail-page banner shows even
    when a site lists both bays. Returns {assetid, machineid, assetnumber}."""
    partner = resolve_dualpath_pairs().partnerbyasset.get(assetid)
    if not partner:
        return None
    partnermach = Machine.query.filter_by(assetid=partner['assetid']).first()
    return {
        'assetid': partner['assetid'],
        'machineid': partnermach.machineid if partnermach else None,
        'assetnumber': partner['assetnumber'],
    }


@machines_bp.route('/<int:machine_id>', methods=['GET'])
@jwt_required(optional=True)
def get_machine(machine_id: int):
    """Get a single machine item with full details."""
    mach = db.session.get(Machine, machine_id)

    if not mach:
        return error_response(
            ErrorCodes.NOT_FOUND,
            f'Machine with ID {machine_id} not found',
            http_code=404
        )

    result = mach.asset.to_dict() if mach.asset else {}
    result['machine'] = mach.to_dict()
    result['dualpathpartner'] = _dualpath_partner_for(mach.assetid)

    return success_response(result)


@machines_bp.route('/by-asset/<int:asset_id>', methods=['GET'])
@jwt_required(optional=True)
def get_machine_by_asset(asset_id: int):
    """Get machine data by asset ID."""
    mach = Machine.query.filter_by(assetid=asset_id).first()

    if not mach:
        return error_response(
            ErrorCodes.NOT_FOUND,
            f'Machine for asset {asset_id} not found',
            http_code=404
        )

    result = mach.asset.to_dict() if mach.asset else {}
    result['machine'] = mach.to_dict()
    result['dualpathpartner'] = _dualpath_partner_for(mach.assetid)

    return success_response(result)


@machines_bp.route('', methods=['POST'])
@jwt_required()
@require_permission('machines.create')
def create_machine():
    """
    Create new machine (creates both Asset and Machine records).

    Required fields:
    - assetnumber: Business identifier

    Optional fields:
    - name, serialnumber, statusid, locationid, businessunitid
    - machinetypeid, vendorid, modelnumberid
    - requiresmanualconfig, islocationonly
    - mapx, mapy, notes
    """
    data = request.get_json()

    if not data:
        return error_response(ErrorCodes.VALIDATION_ERROR, 'No data provided')

    if not data.get('assetnumber'):
        return error_response(ErrorCodes.VALIDATION_ERROR, 'assetnumber is required')

    # Check for duplicate assetnumber
    if Asset.query.filter_by(assetnumber=data['assetnumber']).first():
        return error_response(
            ErrorCodes.CONFLICT,
            f"Asset with number '{data['assetnumber']}' already exists",
            http_code=409
        )

    # Get machine asset type
    machine_type = AssetType.query.filter_by(assettype='machine').first()
    if not machine_type:
        return error_response(
            ErrorCodes.INTERNAL_ERROR,
            'Machine asset type not found. Plugin may not be properly installed.',
            http_code=500
        )

    # Create the core asset
    asset = Asset(
        assetnumber=data['assetnumber'],
        name=data.get('name'),
        gaugelabreference=data.get('gaugelabreference'),
        maintenancereference=data.get('maintenancereference'),
        serialnumber=data.get('serialnumber'),
        assettypeid=machine_type.assettypeid,
        statusid=data.get('statusid', 1),
        locationid=data.get('locationid'),
        businessunitid=data.get('businessunitid'),
        mapx=data.get('mapx'),
        levelid=data.get('levelid'),
        mapy=data.get('mapy'),
        notes=data.get('notes')
    )

    db.session.add(asset)
    db.session.flush()  # Get the assetid

    # Create the machine extension
    mach = Machine(
        assetid=asset.assetid,
        machinetypeid=data.get('machinetypeid'),
        vendorid=data.get('vendorid'),
        modelnumberid=data.get('modelnumberid'),
        requiresmanualconfig=data.get('requiresmanualconfig', False),
        islocationonly=data.get('islocationonly', False),
        lastmaintenancedate=data.get('lastmaintenancedate'),
        nextmaintenancedate=data.get('nextmaintenancedate'),
        maintenanceintervaldays=data.get('maintenanceintervaldays'),
        controllervendorid=data.get('controllervendorid'),
        controllermodelid=data.get('controllermodelid')
    )

    db.session.add(mach)
    db.session.flush()

    # Preserve legacy timestamps in import mode (no-op otherwise)
    apply_import_timestamps(asset, data)

    # Audit log
    AuditLog.log('created', 'Machine', entityid=mach.machineid,
                 entityname=data['assetnumber'])

    db.session.commit()

    result = asset.to_dict()
    result['machine'] = mach.to_dict()

    return success_response(result, message='Machine created', http_code=201)


@machines_bp.route('/<int:machine_id>', methods=['PUT'])
@jwt_required()
@require_permission('machines.edit')
def update_machine(machine_id: int):
    """Update machine (both Asset and Machine records)."""
    mach = db.session.get(Machine, machine_id)

    if not mach:
        return error_response(
            ErrorCodes.NOT_FOUND,
            f'Machine with ID {machine_id} not found',
            http_code=404
        )

    data = request.get_json()
    if not data:
        return error_response(ErrorCodes.VALIDATION_ERROR, 'No data provided')

    asset = mach.asset

    # An UPDATE may not blank the asset number. Create validates it and the
    # column is NOT NULL, but the conflict check below only runs when the value
    # DIFFERS, and '' never collides with anything - so a payload carrying an
    # empty assetnumber wrote it straight through. A form that loaded blank
    # (a failed reference load, a partial fetch) then saved the blank over a
    # real record.
    if 'assetnumber' in data and not (data['assetnumber'] or '').strip():
        return error_response(
            ErrorCodes.VALIDATION_ERROR,
            'assetnumber cannot be empty')

    # Check for conflicting assetnumber
    if 'assetnumber' in data and data['assetnumber'] != asset.assetnumber:
        if Asset.query.filter_by(assetnumber=data['assetnumber']).first():
            return error_response(
                ErrorCodes.CONFLICT,
                f"Asset with number '{data['assetnumber']}' already exists",
                http_code=409
            )

    # Track changes for audit log
    changes = {}

    # Update asset fields
    asset_fields = ['assetnumber', 'name', 'gaugelabreference',
                    'maintenancereference', 'serialnumber', 'statusid',
                    'locationid', 'businessunitid', 'mapx', 'mapy', 'levelid',
                    'notes', 'isactive']
    for key in asset_fields:
        if key in data:
            old_val = getattr(asset, key)
            new_val = data[key]
            if old_val != new_val:
                changes[key] = {'old': old_val, 'new': new_val}
            setattr(asset, key, data[key])

    # Update machine fields
    machine_fields = ['machinetypeid', 'vendorid', 'modelnumberid',
                      'requiresmanualconfig', 'islocationonly',
                      'lastmaintenancedate', 'nextmaintenancedate', 'maintenanceintervaldays',
                      'controllervendorid', 'controllermodelid']
    for key in machine_fields:
        if key in data:
            old_val = getattr(mach, key)
            new_val = data[key]
            if old_val != new_val:
                changes[key] = {'old': old_val, 'new': new_val}
            setattr(mach, key, data[key])

    # Audit log if there were changes
    if changes:
        AuditLog.log('updated', 'Machine', entityid=mach.machineid,
                     entityname=asset.assetnumber, changes=changes)

    apply_import_timestamps(asset, data)
    db.session.commit()

    result = asset.to_dict()
    result['machine'] = mach.to_dict()

    return success_response(result, message='Machine updated')


@machines_bp.route('/<int:machine_id>', methods=['DELETE'])
@jwt_required()
@require_permission('machines.delete')
def delete_machine(machine_id: int):
    """Delete (soft delete) machine."""
    mach = db.session.get(Machine, machine_id)

    if not mach:
        return error_response(
            ErrorCodes.NOT_FOUND,
            f'Machine with ID {machine_id} not found',
            http_code=404
        )

    # Soft delete the asset (machine extension will stay linked)
    mach.asset.isactive = False

    # Audit log
    AuditLog.log('deleted', 'Machine', entityid=mach.machineid,
                 entityname=mach.asset.assetnumber)

    db.session.commit()

    return success_response(message='Machine deleted')


# =============================================================================
# Dashboard
# =============================================================================

@machines_bp.route('/dashboard/summary', methods=['GET'])
@jwt_required(optional=True)
def dashboard_summary():
    """Get machine dashboard summary data."""
    # Dualpath single-machine collapse: hide the secondary bay from counts so a
    # dual-bay pair counts once. Gated on the site setting (default on).
    secondaryassetids = set()
    if dualpath_single_machine_enabled():
        secondaryassetids = resolve_dualpath_pairs().secondaryassetids

    # Total active machine count
    total_query = db.session.query(Machine).join(Asset).filter(
        Asset.isactive == True
    )
    if secondaryassetids:
        total_query = total_query.filter(Asset.assetid.notin_(secondaryassetids))
    total = total_query.count()

    # Count by machine type
    by_type_query = db.session.query(
        MachineType.machinetype,
        db.func.count(Machine.machineid)
    ).join(Machine, Machine.machinetypeid == MachineType.machinetypeid
    ).join(Asset, Asset.assetid == Machine.assetid
    ).filter(Asset.isactive == True)
    if secondaryassetids:
        by_type_query = by_type_query.filter(Asset.assetid.notin_(secondaryassetids))
    by_type = by_type_query.group_by(MachineType.machinetype).all()

    # Count by status
    from shopdb.api import AssetStatus
    by_status = db.session.query(
        AssetStatus.status,
        db.func.count(Machine.machineid)
    ).join(Asset, Asset.assetid == Machine.assetid
    ).join(AssetStatus, AssetStatus.statusid == Asset.statusid
    ).filter(Asset.isactive == True
    ).group_by(AssetStatus.status
    ).all()

    return success_response({
        'total': total,
        'bytype': [{'type': t, 'count': c} for t, c in by_type],
        'bystatus': [{'status': s, 'count': c} for s, c in by_status]
    })


@machines_bp.route('/dashboard/outofservice', methods=['GET'])
@jwt_required()
@require_permission('machines.view')
def dashboard_outofservice():
    """Machines whose status says they are not running.

    Anything that is not In Use: In Repair, Lost, Returned, and so on. Someone
    is supposed to be chasing each of these, and today they are visible only to
    whoever thinks to filter the machines list by status.

    Inventory is excluded - a spare on a shelf is not a problem, it is stock.
    """
    from shopdb.api import AssetStatus

    ignored = ('In Use', 'Inventory')

    rows = (db.session.query(Machine, Asset, AssetStatus)
            .join(Asset, Asset.assetid == Machine.assetid)
            .join(AssetStatus, AssetStatus.statusid == Asset.statusid)
            .filter(Asset.isactive.is_(True),
                    AssetStatus.status.notin_(ignored))
            .order_by(Asset.assetnumber)
            .limit(50).all())

    return success_response([{
        'assetid': asset.assetid,
        'assetnumber': asset.assetnumber or str(asset.assetid),
        'name': asset.name,
        'status': status.status,
    } for _machine, asset, status in rows])
