"""黑板数据库连接管理（per-project SQLite）"""

from __future__ import annotations

import sqlite3
from pathlib import Path
from typing import Optional


def init_db(db_path: Path) -> None:
    """初始化数据库，创建全部表"""
    db_path.parent.mkdir(parents=True, exist_ok=True)
    conn = _connect(db_path)
    try:
        for stmt in _SCHEMA_STATEMENTS:
            conn.execute(stmt)
        conn.commit()
    finally:
        conn.close()


def get_connection(db_path: Path) -> sqlite3.Connection:
    """获取数据库连接（WAL + busy_timeout + foreign_keys）"""
    return _connect(db_path)


def _connect(db_path: Path) -> sqlite3.Connection:
    conn = sqlite3.connect(str(db_path))
    conn.row_factory = sqlite3.Row
    conn.execute("PRAGMA journal_mode=WAL")
    conn.execute("PRAGMA foreign_keys=ON")
    conn.execute("PRAGMA busy_timeout=5000")
    return conn


# ---------------------------------------------------------------------------
# 状态机
# ---------------------------------------------------------------------------

VALID_STATUSES = frozenset({
    "pending", "claimed", "working", "review",
    "done", "failed", "blocked", "cancelled",
})

TERMINAL_STATUSES = frozenset({"done", "cancelled"})

VALID_TRANSITIONS = {
    "pending":   {"claimed", "cancelled"},
    "claimed":   {"working", "pending", "cancelled"},
    "working":   {"review", "blocked", "failed", "cancelled"},
    "review":    {"done", "pending", "failed", "cancelled"},
    "blocked":   {"pending", "cancelled"},
    "done":      set(),
    "failed":    {"pending"},
    "cancelled":  set(),
}

COMMENT_TYPES = frozenset({
    "general", "handoff", "observation", "rebuttal",
    "rebuttal_response", "debate_argument", "debate_rebuttal", "debate_judgment",
})

SEVERITY_LEVELS = frozenset({"blocking", "warning", "info", "audit"})

EVENT_TYPES = frozenset({
    "task_created", "task_claimed", "task_started", "task_completed",
    "task_failed", "task_blocked", "task_unblocked", "task_reviewed",
    "task_cancelled", "task_retried",
    "comment_added", "output_written", "observation_added", "decision_recorded",
    "agent_spawned", "agent_completed", "agent_zombie_detected",
    "session_spawned", "session_archived", "session_cleanup",
    "daemon_tick", "daemon_manual_tick",
})

OUTPUT_TYPES = frozenset({"code", "document", "data", "config", "other"})

REVIEW_TYPES = frozenset({"plan_review", "output_review", "guardrail", "final_review"})
VERDICT_TYPES = frozenset({"approved", "rejected", "needs_revision"})

EXPERIENCE_SOURCES = frozenset({
    "task_completion", "error_correction", "review_finding", "manual",
})
EXPERIENCE_CATEGORIES = frozenset({
    "pitfall", "best_practice", "pattern", "anti_pattern",
})
EXPERIENCE_STATUSES = frozenset({"draft", "active", "deprecated"})

ATTEMPT_OUTCOMES = frozenset({
    "completed", "blocked", "crashed", "timed_out", "spawn_failed", "reclaimed",
})


# ---------------------------------------------------------------------------
# Schema - split into individual statements to avoid SQLite 3.51 CHECK bug
# (table-level CHECK as non-last column definition causes parse error)
# ---------------------------------------------------------------------------

_SCHEMA_STATEMENTS = [
    # tasks
    """CREATE TABLE IF NOT EXISTS tasks (
        id TEXT PRIMARY KEY,
        title TEXT NOT NULL,
        description TEXT,
        status TEXT NOT NULL DEFAULT 'pending' CHECK (status IN ('pending','claimed','working','review','done','failed','blocked','cancelled')),
        assignee TEXT,
        assigned_by TEXT,
        depends_on TEXT,
        parent_task TEXT,
        priority INTEGER NOT NULL DEFAULT 5,
        task_type TEXT,
        created_at TEXT NOT NULL DEFAULT (datetime('now')),
        updated_at TEXT NOT NULL DEFAULT (datetime('now')),
        claimed_at TEXT,
        started_at TEXT,
        completed_at TEXT,
        deadline TEXT,
        retry_count INTEGER NOT NULL DEFAULT 0,
        max_retries INTEGER NOT NULL DEFAULT 2,
        must_haves TEXT,
        risk_level TEXT DEFAULT 'standard',
        estimated_duration_minutes INTEGER,
        escalated INTEGER DEFAULT 0
    )""",
    "CREATE INDEX IF NOT EXISTS idx_tasks_status ON tasks(status)",
    "CREATE INDEX IF NOT EXISTS idx_tasks_assignee ON tasks(assignee)",
    "CREATE INDEX IF NOT EXISTS idx_tasks_parent ON tasks(parent_task)",

    # comments
    """CREATE TABLE IF NOT EXISTS comments (
        id INTEGER PRIMARY KEY AUTOINCREMENT,
        task_id TEXT NOT NULL REFERENCES tasks(id),
        author TEXT NOT NULL,
        comment_type TEXT NOT NULL DEFAULT 'general' CHECK (comment_type IN ('general','handoff','observation','rebuttal','rebuttal_response','debate_argument','debate_rebuttal','debate_judgment')),
        body TEXT NOT NULL,
        mentions TEXT,
        created_at TEXT NOT NULL DEFAULT (datetime('now'))
    )""",
    "CREATE INDEX IF NOT EXISTS idx_comments_task ON comments(task_id)",
    "CREATE INDEX IF NOT EXISTS idx_comments_type ON comments(task_id, comment_type)",
    "CREATE INDEX IF NOT EXISTS idx_comments_author ON comments(author)",

    # outputs
    """CREATE TABLE IF NOT EXISTS outputs (
        id INTEGER PRIMARY KEY AUTOINCREMENT,
        task_id TEXT NOT NULL REFERENCES tasks(id),
        agent TEXT NOT NULL,
        output_type TEXT NOT NULL CHECK (output_type IN ('code','document','data','config','other')),
        title TEXT NOT NULL,
        content_path TEXT,
        summary TEXT,
        metadata TEXT,
        attempt_number INTEGER DEFAULT 1,
        created_at TEXT NOT NULL DEFAULT (datetime('now'))
    )""",
    "CREATE INDEX IF NOT EXISTS idx_outputs_task ON outputs(task_id)",

    # decisions
    """CREATE TABLE IF NOT EXISTS decisions (
        id INTEGER PRIMARY KEY AUTOINCREMENT,
        task_id TEXT NOT NULL REFERENCES tasks(id),
        decider TEXT NOT NULL,
        decision TEXT NOT NULL,
        rationale TEXT NOT NULL,
        alternatives TEXT,
        created_at TEXT NOT NULL DEFAULT (datetime('now'))
    )""",
    "CREATE INDEX IF NOT EXISTS idx_decisions_task ON decisions(task_id)",

    # observations
    """CREATE TABLE IF NOT EXISTS observations (
        id INTEGER PRIMARY KEY AUTOINCREMENT,
        task_id TEXT NOT NULL REFERENCES tasks(id),
        observer TEXT NOT NULL,
        severity TEXT NOT NULL DEFAULT 'info' CHECK (severity IN ('blocking','warning','info','audit')),
        body TEXT NOT NULL,
        resolved_by TEXT,
        resolved_at TEXT,
        created_at TEXT NOT NULL DEFAULT (datetime('now'))
    )""",

    # events
    """CREATE TABLE IF NOT EXISTS events (
        id INTEGER PRIMARY KEY AUTOINCREMENT,
        task_id TEXT,
        agent TEXT,
        event_type TEXT NOT NULL,
        detail TEXT,
        created_at TEXT NOT NULL DEFAULT (datetime('now'))
    )""",
    "CREATE INDEX IF NOT EXISTS idx_events_task ON events(task_id)",
    "CREATE INDEX IF NOT EXISTS idx_events_time ON events(created_at)",

    # agents
    """CREATE TABLE IF NOT EXISTS agents (
        agent_id TEXT PRIMARY KEY,
        role TEXT,
        current_status TEXT DEFAULT 'idle',
        current_task TEXT,
        last_active TEXT,
        capabilities TEXT
    )""",

    # task_attempts
    """CREATE TABLE IF NOT EXISTS task_attempts (
        id INTEGER PRIMARY KEY AUTOINCREMENT,
        task_id TEXT NOT NULL REFERENCES tasks(id),
        attempt_number INTEGER NOT NULL,
        agent TEXT NOT NULL,
        outcome TEXT NOT NULL CHECK (outcome IN ('completed','blocked','crashed','timed_out','spawn_failed','reclaimed')),
        exit_code INTEGER,
        log_path TEXT,
        summary TEXT,
        metadata TEXT,
        started_at TEXT NOT NULL DEFAULT (datetime('now')),
        completed_at TEXT
    )""",
    "CREATE INDEX IF NOT EXISTS idx_attempts_task ON task_attempts(task_id)",

    # reviews
    """CREATE TABLE IF NOT EXISTS reviews (
        id TEXT PRIMARY KEY,
        task_id TEXT NOT NULL REFERENCES tasks(id),
        output_id TEXT,
        reviewer TEXT NOT NULL,
        review_type TEXT NOT NULL CHECK (review_type IN ('plan_review','output_review','guardrail','final_review')),
        verdict TEXT NOT NULL CHECK (verdict IN ('approved','rejected','needs_revision')),
        confidence REAL,
        round INTEGER NOT NULL DEFAULT 1,
        max_rounds INTEGER NOT NULL DEFAULT 3,
        consensus_reached INTEGER DEFAULT 0,
        summary TEXT NOT NULL,
        detail_path TEXT,
        created_at TEXT NOT NULL DEFAULT (datetime('now'))
    )""",
    "CREATE INDEX IF NOT EXISTS idx_reviews_task ON reviews(task_id)",
    "CREATE INDEX IF NOT EXISTS idx_reviews_output ON reviews(output_id)",

    # experiences
    """CREATE TABLE IF NOT EXISTS experiences (
        experience_id TEXT PRIMARY KEY,
        source TEXT NOT NULL CHECK (source IN ('task_completion','error_correction','review_finding','manual')),
        task_id TEXT,
        summary TEXT NOT NULL,
        category TEXT NOT NULL CHECK (category IN ('pitfall','best_practice','pattern','anti_pattern')),
        confidence REAL DEFAULT 0.8,
        status TEXT DEFAULT 'active' CHECK (status IN ('draft','active','deprecated')),
        skill_id TEXT,
        usage_count INTEGER DEFAULT 0,
        last_used_at TEXT,
        created_at TEXT NOT NULL,
        created_by TEXT NOT NULL,
        updated_at TEXT,
        deprecated_reason TEXT
    )""",

    # experience_tags
    """CREATE TABLE IF NOT EXISTS experience_tags (
        experience_id TEXT NOT NULL REFERENCES experiences(experience_id),
        tag TEXT NOT NULL,
        PRIMARY KEY (experience_id, tag)
    )""",
    "CREATE INDEX IF NOT EXISTS idx_exptags_tag ON experience_tags(tag)",
]