"""Kanban: sign-in, the board, commercial review and card movement."""
import hashlib
import os
import secrets
from datetime import datetime, timedelta, timezone
from typing import Literal
from uuid import UUID

from fastapi import APIRouter, Depends, HTTPException, Query, Request, Response
from psycopg.types.json import Jsonb

from ..core import db
from ..core.auth import (COOKIE_SECURE, DUMMY_PASSWORD_HASH, audit, client_ip, operator,
                    password_matches, throttle)
from ..core.models import Move, OperatorLogin, Resolution, Review
from ..core.pricing import price
from ..printjobs import queue as queue_print_files
from ..runtime import (BOARD_FINISHED_LIMIT, BOARD_QUOTE_LIMIT, STATES, TRANSITIONS,
                       enqueue, freight, quote_view, storage, upload_row)
from ..scanning import require_clean

router = APIRouter()

@router.post('/api/operator/login')
def operator_login(body: OperatorLogin, request: Request, response: Response):
    email = body.email
    throttle('operator:'+email, request)
    with db.connect() as c:
        account = c.execute('SELECT * FROM dtf_local.operators WHERE email=%s', (email,)).fetchone()
        if not c.execute('SELECT 1 FROM dtf_local.operators WHERE active LIMIT 1').fetchone():
            raise HTTPException(503, 'No Kanban operator account is configured')
    # Comparable password work whether or not the account exists or is active.
    stored = account['password_hash'] if account else DUMMY_PASSWORD_HASH
    matches = password_matches(body.password, stored)
    if not account or not account['active'] or not matches:
        audit('operator_login_failed', ip=client_ip(request), operator=email)
        raise HTTPException(401, 'Invalid operator login')
    token = secrets.token_urlsafe(32)
    with db.connect() as c:
        previous = hashlib.sha256(request.cookies.get('dtf_operator','').encode()).hexdigest()
        c.execute('DELETE FROM dtf_local.operator_sessions WHERE token_hash=%s', (previous,))
        c.execute('INSERT INTO dtf_local.operator_sessions(token_hash,username) VALUES(%s,%s)',
                  (hashlib.sha256(token.encode()).hexdigest(), email))
        c.execute('UPDATE dtf_local.operators SET last_login_at=now() WHERE id=%s', (account['id'],))
    response.set_cookie('dtf_operator', token, httponly=True, secure=COOKIE_SECURE,
                        samesite='strict', path='/api/operator', max_age=28800)
    audit('operator_login_success', operator=email)
    return {'ok': True}

@router.post('/api/operator/logout')
def operator_logout(request: Request, response: Response):
    with db.connect() as c:
        digest = hashlib.sha256(request.cookies.get('dtf_operator','').encode()).hexdigest()
        c.execute('DELETE FROM dtf_local.operator_sessions WHERE token_hash=%s', (digest,))
    response.delete_cookie('dtf_operator', path='/api/operator', httponly=True,
                           secure=COOKIE_SECURE, samesite='strict')
    audit('operator_logout')
    return {'ok': True}

@router.get('/api/operator/board')
def board(user=Depends(operator)):
    with db.connect() as c:
        # Everything still in progress, however old: an operator must never lose a
        # card they can act on. Finished orders are terminal and only accumulate,
        # so the board carries a recent window of them and reports the true total.
        active = c.execute("SELECT * FROM dtf_local.orders WHERE state<>'fin' ORDER BY created_at").fetchall()
        finished = c.execute("SELECT * FROM dtf_local.orders WHERE state='fin' ORDER BY created_at DESC LIMIT %s",
                             (BOARD_FINISHED_LIMIT,)).fetchall()
        finished_total = c.execute("SELECT count(*) AS n FROM dtf_local.orders WHERE state='fin'").fetchone()['n']
        pending = c.execute('''SELECT q.* FROM dtf_local.quotes q
            LEFT JOIN dtf_local.orders o ON o.quote_id=q.id
            WHERE o.id IS NULL AND q.approved IS NULL
            ORDER BY q.created_at DESC,q.id DESC LIMIT %s''', (BOARD_QUOTE_LIMIT,)).fetchall()
        approved = c.execute('''SELECT q.* FROM dtf_local.quotes q
            LEFT JOIN dtf_local.orders o ON o.quote_id=q.id
            WHERE o.id IS NULL AND q.approved IS NOT NULL
            ORDER BY q.created_at DESC,q.id DESC LIMIT 20''').fetchall()
        pending_total = c.execute('''SELECT count(*) AS n FROM dtf_local.quotes q
            LEFT JOIN dtf_local.orders o ON o.quote_id=q.id
            WHERE o.id IS NULL AND q.approved IS NULL''').fetchone()['n']
        approved_total = c.execute('''SELECT count(*) AS n FROM dtf_local.quotes q
            LEFT JOIN dtf_local.orders o ON o.quote_id=q.id
            WHERE o.id IS NULL AND q.approved IS NOT NULL''').fetchone()['n']
        orders = active + list(reversed(finished))
        generated = c.execute('''SELECT p.order_id,p.item_index,p.status,p.upload_id,p.detail,u.name
            FROM dtf_local.print_files p LEFT JOIN dtf_local.uploads u ON u.id=p.upload_id
            WHERE p.order_id=ANY(%s) ORDER BY p.item_index''', ([o['id'] for o in orders],)).fetchall()
        for order in orders:
            order['print_files'] = [row for row in generated if row['order_id'] == order['id']]
        # A paid notification that did not become an order is money received
        # for nothing the factory will make. It stays on the board until a
        # person records what was done about it.
        refused = c.execute('''SELECT id,provider,event_id,reference,status,amount_cents,received_at,outcome
            FROM dtf_local.payment_events WHERE (outcome LIKE 'refused%' OR outcome LIKE 'attention%') AND resolved_at IS NULL
            ORDER BY received_at LIMIT 100''').fetchall()
        return {'states': STATES, 'transitions': TRANSITIONS,
                'orders': orders, 'payment_issues': refused,
                'finished_shown': len(finished), 'finished_total': finished_total,
                'quotes': [quote_view(c, q) for q in pending + approved],
                'pending_total': pending_total, 'approved_total': approved_total,
                'events': c.execute('SELECT * FROM dtf_local.outbox ORDER BY id DESC LIMIT 100').fetchall()}

@router.get('/api/operator/quotes')
def quote_page(kind: Literal['pending','approved'], before_created_at: datetime | None = None,
               before_id: UUID | None = None, limit: int = Query(default=50, ge=1, le=100),
               user=Depends(operator)):
    if (before_created_at is None) != (before_id is None):
        raise HTTPException(422, 'Both quote cursor fields are required')
    approved_filter = 'q.approved IS NULL' if kind == 'pending' else 'q.approved IS NOT NULL'
    cursor = 'AND (q.created_at,q.id)<(%s,%s)' if before_created_at else ''
    params = ((before_created_at,before_id) if before_created_at else ()) + (limit+1,)
    with db.connect() as c:
        rows = c.execute(f'''SELECT q.* FROM dtf_local.quotes q
            LEFT JOIN dtf_local.orders o ON o.quote_id=q.id
            WHERE o.id IS NULL AND {approved_filter} {cursor}
            ORDER BY q.created_at DESC,q.id DESC LIMIT %s''', params).fetchall()
        return {'quotes':[quote_view(c,row) for row in rows[:limit]],
                'has_more':len(rows)>limit}

@router.post('/api/operator/quotes/{uid}/approve')
def approve(uid: UUID, body: Review, user=Depends(operator)):
    with db.connect() as c:
        row = c.execute('SELECT * FROM dtf_local.quotes WHERE id=%s FOR UPDATE', (uid,)).fetchone()
        if not row:
            raise HTTPException(404, 'Quote not found')
        if row['approved']:
            raise HTTPException(409, 'Approved quotes are immutable; request a new quote')
        draft = row['draft']
        if any(item.get('production', {}).get('version') != 2 for item in draft['items']):
            raise HTTPException(409, 'Quote uses an obsolete production layout; customer must request a new quote')
        if len(body.items) != len(draft['items']):
            raise HTTPException(422, 'Review must cover every item')
        items = []
        for item, original in zip(body.items, draft['items']):
            if item.mode != original['mode'] or list(map(str,item.uploads)) != original['uploads']:
                raise HTTPException(422, 'Product mode and attached files cannot change during review')
            if item.production.model_dump(mode='json') != original['production'] or item.quality_status != original['quality_status'] or item.quality_acknowledged != original['quality_acknowledged']:
                raise HTTPException(422, 'Production instructions and customer acknowledgement cannot change during commercial review')
            for upload_id in item.uploads:
                require_clean(upload_row(c, upload_id, row['owner']))
            items.append({**price(item.mode, str(item.metres), item.grade),
                          'uploads': original['uploads'], 'production': original['production'],
                          'quality_status': original['quality_status'],
                          'quality_acknowledged': original['quality_acknowledged']})
        quoted_freight = freight.quote(**draft['freight'])
        approved = {'customer': draft['customer'], 'items': items, 'freight': quoted_freight,
                    'destination': draft.get('destination'),
                    'total_cents': sum(i['total_cents'] for i in items)+quoted_freight['total_cents']}
        c.execute('UPDATE dtf_local.quotes SET approved=%s, reviewed_by=%s, approved_at=now() WHERE id=%s', (Jsonb(approved),user,uid))
    return approved

@router.post('/api/operator/orders/{uid}/move')
def move(uid: UUID, body: Move, user=Depends(operator)):
    with db.connect() as c:
        row = c.execute('SELECT * FROM dtf_local.orders WHERE id=%s FOR UPDATE', (uid,)).fetchone()
        if not row:
            raise HTTPException(404, 'Order not found')
        if body.version != row['version']:
            raise HTTPException(409, 'Order changed; refresh the board')
        if body.state == row['state']:
            return row
        if body.state not in TRANSITIONS[row['state']]:
            raise HTTPException(409, 'Move is not allowed from this state')
        if body.state == 'cor' and not body.reason.strip():
            raise HTTPException(422, 'Correction requires a reason')
        if body.state in ('fil','imp'):
            coverage = c.execute('SELECT DISTINCT f.item_index FROM dtf_local.order_files f JOIN dtf_local.uploads u ON u.id=f.upload_id WHERE f.order_id=%s AND f.kind=\'final\' AND f.active AND u.expires_at>now() AND u.purged_at IS NULL AND u.scan_state=\'clean\'', (uid,)).fetchall()
            if {r['item_index'] for r in coverage} != set(range(len(row['snapshot']['items']))):
                raise HTTPException(409, 'Approve a complete final-file set for every item before queueing')
        if body.state == 'cor':
            c.execute("UPDATE dtf_local.order_files SET active=false WHERE order_id=%s AND kind='final'", (uid,))
        c.execute('INSERT INTO dtf_local.movements(order_id,from_state,to_state,operator,reason) VALUES(%s,%s,%s,%s,%s)',
                  (uid,row['state'],body.state,user,body.reason))
        changed = c.execute('UPDATE dtf_local.orders SET state=%s, version=version+1, updated_at=now() WHERE id=%s RETURNING *', (body.state,uid)).fetchone()
        events = {'imp':'production_started','cor':'correction_needed','fin':'ready'}
        if body.state in events:
            for provider in ('tiny','whatsapp'):
                enqueue(c, f'{uid}:{changed["version"]}:{provider}', provider,
                        {'order_id':str(uid), 'number':row['number'], 'event':events[body.state], 'reason':body.reason,
                         'customer_path': f'/portal.html?order={uid}'})
    return changed

@router.post('/api/operator/orders/{uid}/print-files')
def regenerate(uid: UUID, user=Depends(operator)):
    """Queue generation again for items that failed or went to manual preparation,
    and for orders paid before the generator existed."""
    with db.connect() as c:
        row = c.execute('SELECT id,snapshot,state FROM dtf_local.orders WHERE id=%s FOR UPDATE', (uid,)).fetchone()
        if not row:
            raise HTTPException(404, 'Order not found')
        if row['state'] not in ('rec','tra'):
            raise HTTPException(409, 'Print files are generated only before the order is queued')
        if c.execute("SELECT 1 FROM dtf_local.order_files WHERE order_id=%s AND kind='correction' LIMIT 1", (uid,)).fetchone():
            raise HTTPException(409, 'A customer correction replaced the original artwork; prepare the final file by hand')
        queue_print_files(c, uid, len(row['snapshot']['items']), only_missing=True)
        audit('print_file_requeued', order=str(uid), operator=user)
        return c.execute('SELECT * FROM dtf_local.print_files WHERE order_id=%s ORDER BY item_index', (uid,)).fetchall()

@router.post('/api/operator/payment-events/{uid}/resolve')
def resolve_payment(uid: UUID, body: Resolution, user=Depends(operator)):
    with db.connect() as c:
        row = c.execute('''UPDATE dtf_local.payment_events SET resolved_at=now(), resolved_by=%s, resolution=%s
            WHERE id=%s AND (outcome LIKE 'refused%%' OR outcome LIKE 'attention%%') AND resolved_at IS NULL RETURNING id''',
            (user, body.note, uid)).fetchone()
        if not row:
            raise HTTPException(404, 'No open payment issue with this id')
    audit('payment_issue_resolved', payment_event=str(uid), operator=user)
    return {'ok': True}

@router.get('/api/operator/orders/{uid}/history')
def history(uid: UUID, user=Depends(operator)):
    with db.connect() as c:
        return c.execute('SELECT * FROM dtf_local.movements WHERE order_id=%s ORDER BY id', (uid,)).fetchall()

@router.get('/api/operator/uploads/{uid}/download')
def download(uid: UUID, user=Depends(operator)):
    with db.connect() as c:
        row = c.execute('SELECT * FROM dtf_local.uploads WHERE id=%s AND complete', (uid,)).fetchone()
        if not row:
            raise HTTPException(404, 'Completed upload not found')
        if row['expires_at'] <= datetime.now(timezone.utc):
            raise HTTPException(410, 'Artwork retention expired')
        require_clean(row)
    return {'name':row['name'], 'url':storage.download(row['object_key'],row['name']), 'expires_in':300}