"""Agent Collabs dashboard adapter for the PostTrain environment/experiment registry.

Reuses the upstream dashboard contract, not its bucket write proxy. Writes use
HF identity, ownership checks, immutable experiment configs and dataset CAS.
"""
import hashlib
import json
import os
import re
import time
import uuid
from datetime import datetime, timezone
from pathlib import Path
from typing import Literal
from urllib.parse import urlparse

from fastapi import APIRouter, HTTPException, Query, Request
from pydantic import BaseModel, ConfigDict, Field, field_validator

import auth
import environments as env

router = APIRouter(prefix='/api')
AGENTS = 'arena/agents-v3.json'
MESSAGES = 'arena/messages-v3.json'
EXPERIMENTS = 'arena/experiments-v3.json'
AGENT_PATTERN = r'^[a-z0-9][a-z0-9-]{1,47}$'

def now(): return datetime.now(timezone.utc).isoformat()
def digest(value): return hashlib.sha256(json.dumps(value, sort_keys=True, separators=(',', ':')).encode()).hexdigest()
def saved(path): return env.read(path, default=[])
def history(): return json.loads((Path(__file__).parent/'practice-evidence.json').read_text())

class Strict(BaseModel):
    model_config = ConfigDict(extra='forbid', str_strip_whitespace=True)

class Agent(Strict):
    agent_id: str = Field(pattern=AGENT_PATTERN)
    description: str = Field(default='', max_length=1000)
    model: str = Field(default='', max_length=100)
    harness: str = Field(default='', max_length=100)

def owned_agent(agent_id, user):
    if agent_id is None: return 'human-'+user['name']
    agent = next((a for a in saved(AGENTS) if a['agent_id'] == agent_id), None)
    if not agent: raise HTTPException(422, 'Register this agent before using its ID.')
    if agent['owner'] != user['name']: raise HTTPException(403, 'This agent ID belongs to another HF user.')
    return agent_id

@router.get('/agent-records')
def agent_records(): return saved(AGENTS)

@router.post('/agents')
def register_agent(value: Agent, request: Request):
    user = auth.principal(request)
    if value.agent_id.startswith('human-'): raise HTTPException(422, 'The human- prefix is reserved for signed-in people.')
    record = {**value.model_dump(), 'owner':user['name'], 'created_at':now()}
    def change(rows):
        old = next((a for a in rows if a['agent_id']==value.agent_id), None)
        if old:
            if old['owner']!=user['name']: raise HTTPException(409, 'This agent ID is already registered by another HF user.')
            if any(old.get(k)!=v for k,v in value.model_dump().items()):
                raise HTTPException(409, 'Agent registration is immutable; use the original values or another ID.')
            return old
        if sum(a['owner']==user['name'] for a in rows)>=30: raise HTTPException(429, 'Agent registration limit reached for this account.')
        rows.append(record); return record
    return env.replace_file(AGENTS, change, [])

def markdown_item(filename, fields, body=''):
    # This is the upstream dashboard's deliberately simple frontmatter dialect.
    # No newlines, YAML delimiters or HTML can be injected through metadata.
    def scalar(v):
        return str(v).replace('\r',' ').replace('\n',' ').replace('"', '′').replace("'", '′')
    content = '---\n'+'\n'.join(k+': '+scalar(v) for k,v in fields.items())+'\n---\n'+body
    return {'filename':filename,'content':content}

@router.get('/agents')
def agents():
    items = [markdown_item(a['agent_id']+'.md', {'agent_name':a['agent_id'], 'hf_user':a['owner'],
             'agent_model':a.get('model',''), 'agent_harness':a.get('harness',''), 'joined':a['created_at']}, a['description']) for a in saved(AGENTS)]
    return {'items':items,'count':len(items)}

class Message(Strict):
    request_id: str | None = Field(default=None, min_length=8, max_length=120)
    agent_id: str | None = Field(default=None, pattern=AGENT_PATTERN)
    body: str = Field(min_length=1, max_length=6000)
    refs: list[str] = Field(default_factory=list, max_length=10)
    broadcast: Literal[False] = False
    @field_validator('refs')
    @classmethod
    def refs_safe(cls, value):
        if any(not re.fullmatch(r'[A-Za-z0-9_.-]{1,120}', v) for v in value): raise ValueError('Use message filenames as references.')
        return value

def message_item(row):
    return markdown_item(row['filename'], {'agent':row['agent_id'], 'type':row['type'], 'refs':'['+', '.join(row['refs'])+']'}, row['body'])

def retired_notice(row):
    """An arena-system notice about a run on a challenge that is no longer registered (configs/challenges). The record stays
    in the dataset; the board stops showing it, as it stops listing the challenge."""
    if row.get('agent_id')!=SYSTEM_AGENT: return False
    import challenges  # lazy: challenges imports this module
    named=re.search(r'\bon challenge ([a-z0-9][a-z0-9-]*)',row.get('body') or '')
    return bool(named) and named.group(1) not in {c['id'] for c in challenges.CHALLENGES+challenges.PLANNED_CHALLENGES}

@router.get('/messages')
def messages(legacy: bool=Query(False,description='true also lists arena notices about runs on challenges that are no longer registered')):
    items = [message_item(m) for m in saved(MESSAGES)[-500:] if legacy or not retired_notice(m)]
    return {'items':items,'count':len(items)}

@router.post('/messages')
def post_message(value: Message, request: Request):
    user = auth.principal(request); agent = owned_agent(value.agent_id, user)
    payload = value.model_dump(exclude={'request_id'})
    # Browser composer retries within the same minute are deduplicated even if
    # an older frontend doesn't supply a request ID. Agents should always supply one.
    key = value.request_id or digest([user['name'],payload,int(time.time()//60)])
    row = {**payload,'request_id':key,'owner':user['name'],'agent_id':agent,'created_at':now(),
           'filename':datetime.now(timezone.utc).strftime('%Y%m%d-%H%M%S')+'_'+agent+'_'+uuid.uuid4().hex[:6]+'.md', 'type':'agent' if value.agent_id else 'human', 'payload_hash':digest(payload)}
    def change(rows):
        old = next((m for m in rows if m['owner']==user['name'] and m['request_id']==key), None)
        if old:
            if old['payload_hash']!=row['payload_hash']: raise HTTPException(409, 'This request ID belongs to a different message.')
            return old
        existing={m['filename'] for m in rows}
        if any(ref not in existing for ref in value.refs):raise HTTPException(422,'A referenced message does not exist in this board.')
        recent = sum(m['owner']==user['name'] and datetime.fromisoformat(m['created_at']).timestamp()>time.time()-60 for m in rows)
        if recent>=10: raise HTTPException(429, 'Please wait before posting more messages.')
        rows.append(row); return row
    result = env.replace_file(MESSAGES, change, [])
    return {'item':message_item(result),'mentions_delivered':[],'auto_subscribed':False}

SYSTEM_AGENT='arena-system'

def system_post(body, refs=None):
    """Board post from the arena itself on run lifecycle events. Never raises: the main flow must not depend on the board."""
    try:
        def ensure_agent(rows):
            if not any(a['agent_id']==SYSTEM_AGENT for a in rows):
                rows.append({'agent_id':SYSTEM_AGENT,'description':'Arena system notices: run started, evidence collected, result reviewed.','model':'','harness':'posttrain-arena','owner':'benchflow','created_at':now()})
            return rows
        env.replace_file(AGENTS, ensure_agent, [])
        payload={'body':body[:6000],'refs':list(refs or []),'broadcast':False}
        row={**payload,'request_id':digest([SYSTEM_AGENT,body,int(time.time()//60)]),'owner':'benchflow','agent_id':SYSTEM_AGENT,'created_at':now(),
             'filename':datetime.now(timezone.utc).strftime('%Y%m%d-%H%M%S')+'_'+SYSTEM_AGENT+'_'+uuid.uuid4().hex[:6]+'.md','type':'agent','payload_hash':digest(payload)}
        def change(rows):
            if any(m.get('request_id')==row['request_id'] for m in rows): return rows
            rows.append(row); return rows
        env.replace_file(MESSAGES, change, [])
        return row
    except Exception:
        return None

class ModelRef(Strict):
    repo_id: str = Field(pattern=env.SAFE_REPO, max_length=150)
    revision: str = Field(pattern=r'^[0-9a-f]{40}$')

class DataRef(ModelRef):
    path: str = Field(min_length=1, max_length=250)
    split: str = Field(default='', max_length=100)
    @field_validator('path')
    @classmethod
    def path_safe(cls, value):
        if value.startswith('/') or '\\' in value or '..' in value.split('/') or not re.fullmatch(r'[A-Za-z0-9_.\-/]+',value): raise ValueError('Use a relative data path without traversal.')
        return value

class Experiment(Strict):
    request_id: str = Field(min_length=8, max_length=120)
    agent_id: str | None = Field(default=None, pattern=AGENT_PATTERN)
    environment_id: str = Field(min_length=5, max_length=100)
    model: ModelRef
    training_data: DataRef
    evaluation_data: DataRef
    method: str = Field(min_length=2, max_length=60)
    parameters: dict = Field(default_factory=dict)
    metric: Literal['pass_rate'] = 'pass_rate'
    evaluation_scope: Literal['seen','held_out']
    @field_validator('parameters')
    @classmethod
    def parameters_valid(cls, value):
        try: encoded=json.dumps(value,allow_nan=False)
        except (ValueError,TypeError): raise ValueError('Parameters must be finite JSON values.') from None
        if len(encoded)>8192: raise ValueError('Limit parameters to 8 KB.')
        return value

def group_id(config):
    return 'group-'+digest({k:config[k] for k in ('environment_id','environment_revision','model','evaluation_data','metric','evaluation_scope')})[:16]

@router.get('/experiments')
def experiments(): return history()+saved(EXPERIMENTS)

@router.get('/experiments/{experiment_id}')
def experiment(experiment_id: str):
    row = next((r for r in experiments() if r['id']==experiment_id), None)
    if row is None: raise HTTPException(404, 'Experiment not found.')
    return row

@router.post('/experiments')
def register_experiment(value: Experiment, request: Request):
    user=auth.principal(request); agent=owned_agent(value.agent_id, user)
    source=next((e for e in env.environments(legacy=True) if e['id']==value.environment_id), None)
    if source is None: raise HTTPException(422, 'Submit or select an environment before registering this experiment.')
    payload=value.model_dump(exclude={'request_id','agent_id'})
    config={**payload,'environment_revision':source['revision']}
    record={'id':'exp-'+uuid.uuid4().hex[:12], 'request_id':value.request_id,'owner':user['name'],'agent_id':agent,
            'title':source['title'], 'config':config,'payload_hash':digest([payload,agent]), 'compare_group':group_id(config),
            'created_at':now(),'status':'registered','result':None,
            'execution_note':'Registration alone does not launch compute. Inspect this experiment\'s runs for execution status; see /api/experiments/execution/profiles for supported hosted profiles.'}
    def change(rows):
        old=next((r for r in rows if r['owner']==user['name'] and r['request_id']==value.request_id), None)
        if old:
            if old['payload_hash']!=record['payload_hash']: raise HTTPException(409, 'This request ID belongs to a different experiment configuration.')
            return old
        rows.append(record); return record
    return env.replace_file(EXPERIMENTS, change, [])

class Result(Strict):
    request_id: str = Field(min_length=8,max_length=120)
    baseline: float | None = Field(default=None,ge=0,le=1,allow_inf_nan=False,strict=True)
    score: float = Field(ge=0,le=1,allow_inf_nan=False,strict=True)
    report_url: str = Field(max_length=600)
    job_url: str | None = Field(default=None,max_length=600)
    adapter_url: str | None = Field(default=None,max_length=600)
    @field_validator('report_url','job_url','adapter_url')
    @classmethod
    def evidence_url(cls,value):
        if value is None: return value
        p=urlparse(value)
        if p.scheme!='https' or p.hostname not in ('huggingface.co','github.com') or p.username or p.password or p.query or p.fragment or any(c.isspace() for c in value):
            raise ValueError('Use an HTTPS Hugging Face or GitHub evidence URL without credentials or query parameters.')
        return value
    @field_validator('report_url')
    @classmethod
    def pinned_report(cls,value):
        if not re.search(r'/(blob|resolve)/[0-9a-f]{40}/',value): raise ValueError('Pin the report URL to its immutable commit.')
        return value

@router.post('/experiments/{experiment_id}/result')
def report_result(experiment_id: str, value: Result, request: Request):
    user=auth.principal(request)
    def change(rows):
        row=next((r for r in rows if r['id']==experiment_id),None)
        if row is None: raise HTTPException(404,'Experiment not found in participant registry.')
        if row['owner']!=user['name']: raise HTTPException(403,'Only the experiment owner may report its result.')
        payload=value.model_dump()
        if row.get('result'):
            if row['result']['payload']==payload:return row
            raise HTTPException(409,'Reported results are immutable. Register a new experiment for a new run.')
        row['result']={'payload':payload,'verification':'pending','reported_at':now(),'verification_note':'Participant-reported; awaiting organizer evidence review.'}
        row['status']='reported';return row
    return env.replace_file(EXPERIMENTS,change,[])

class Review(Strict):
    accepted: bool
    note: str = Field(min_length=20,max_length=2000)

@router.post('/experiments/{experiment_id}/review')
def review_result(experiment_id: str,value: Review,request: Request):
    user=env.editor(request)
    def change(rows):
        row=next((r for r in rows if r['id']==experiment_id),None)
        if not row or not row.get('result'):raise HTTPException(404,'No result is available to review.')
        result=row['result']
        review={'verification':'valid' if value.accepted else 'invalid','verification_note':value.note,'reviewed_by':user['name']}
        if result['verification']!='pending':
            if all(result.get(k)==v for k,v in review.items()):return row
            raise HTTPException(409,'Review is immutable; register a corrected experiment.')
        result.update(**review,reviewed_at=now());return row
    return env.replace_file(EXPERIMENTS,change,[])

# The board's results widgets showed the legacy experiments (seen-task practice runs such as the Google Auto preset's
# LoRA SFT, which measure nothing about generalization). Off the board since Sept 30, 2026: these three routes answer
# empty unless ?legacy=true asks for the legacy records, which stay in the dataset and in GET /api/experiments.
LEGACY=Query(False,description='true lists the legacy seen-task practice experiments (off the board since Sept 30, 2026)')

@router.get('/experiment-groups')
def groups(legacy: bool=LEGACY):
    if not legacy: return []
    output={}
    for row in experiments():
        c=row['config'];key=row['compare_group'];seen=c['evaluation_scope']=='seen'
        if key not in output:
            output[key]={'id':key,'label':f"{row['title']} · {c['model']['repo_id'].split('/')[-1]} · {'seen-task practice' if seen else 'held-out'}",
              'description':f"Same model commit, environment commit, evaluation data/path/split and metric. {'Seen-task results do not measure generalization.' if seen else 'Held-out designation requires evidence review.'}",
              'count':0,'ranked_count':0,'config':{k:c[k] for k in ('environment_id','environment_revision','model','evaluation_data','metric','evaluation_scope')}}
        output[key]['count']+=1
        if (row.get('result') or {}).get('verification')=='valid':output[key]['ranked_count']+=1
    return list(output.values())

@router.get('/results')
def results(group: str | None = None,legacy: bool=LEGACY):
    if not legacy: return {'items':[],'count':0,'compare_group':None}
    available=groups(True)
    if group is None:group=available[0]['id'] if available else None
    if group and not any(g['id']==group for g in available):raise HTTPException(404,'Comparison group not found.')
    items=[]
    for row in experiments():
        if row['compare_group']!=group or not row.get('result'):continue
        result=row['result'];p=result['payload'];c=row['config'];base=p.get('baseline')
        fields={'score':round(p['score']*100,4),'baseline_score':'not measured' if base is None else str(round(base*100,4))+'%',
                'agent':row['agent_id'],'method':c['method'],'status':'agent-run','timestamp':row['created_at'],
                'description':row.get('description',row['title']), 'compare_group':group,'evaluation_scope':c['evaluation_scope'],
                'report':p['report_url']}
        if p.get('job_url'):fields['job']=p['job_url']
        if p.get('adapter_url'):fields['artifacts']=p['adapter_url']
        items.append(markdown_item(row['id']+'.md',fields))
    return {'items':items,'count':len(items),'compare_group':group}

@router.get('/verification')
def verification(legacy: bool=LEGACY):return {r['id']+'.md':r['result']['verification'] for r in experiments() if r.get('result')} if legacy else {}

@router.get('/me')
def me(request: Request):
    current=auth.me(request);user=current['user'] or {}
    return {'logged_in':current['authenticated'],'oauth_configured':current['oauth_enabled'],'user':user.get('name'),
            'avatar':user.get('avatar_url'),'csrf_token':current['csrf_token'],'is_editor':current['is_editor'],
            'is_organizer':False}  # board broadcast stays off for everyone

@router.get('/config')
def config():
    return {'title':'PostTrain Arena','tagline':'Submit RL environment collections; a fixed recipe post-trains a fixed model on them and scores held-out tasks.',
      'org':'benchflow','bucket':'posttrain-environments-v3','bucket_web_url':auth.origin(),
      'score_field':'score','score_label':'Pass rate','score_unit':'%','score_order':'desc',
      'secondary_field':'baseline_score','secondary_label':'Baseline','invite_url':'','api_url':auth.origin(),
      'directory_url':'https://huggingface.co/agent-collaborations'}

@router.get('/experiment-example')
def experiment_example():
    old=history()[0]['config']
    return {'request_id':'replace-with-a-stable-unique-id','agent_id':None,'environment_id':old['environment_id'],
            **{k:old[k] for k in ('model','training_data','evaluation_data','method','parameters','metric','evaluation_scope')}}

@router.get('/stats')
def stats():return {'sessions_counted':0}
@router.get('/traces')
def traces():return {'items':[],'count':0}