"""SQLite database operations for DMARC reports"""

import sqlite3
import json
from pathlib import Path


class Database:
    def __init__(self, db_path):
        self.db_path = db_path

    def init_db(self):
        """Initialize the database schema"""
        conn = sqlite3.connect(self.db_path)
        cursor = conn.cursor()

        # Create reports table
        cursor.execute('''
            CREATE TABLE IF NOT EXISTS reports (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                org_name TEXT,
                email TEXT,
                report_id TEXT UNIQUE,
                date_begin DATETIME,
                date_end DATETIME,
                domain TEXT,
                policy_p TEXT,
                policy_sp TEXT,
                policy_pct INTEGER,
                policy_adkim TEXT,
                policy_aspf TEXT,
                created_at DATETIME DEFAULT CURRENT_TIMESTAMP
            )
        ''')

        # Create records table
        cursor.execute('''
            CREATE TABLE IF NOT EXISTS records (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                report_id INTEGER,
                source_ip TEXT,
                count INTEGER,
                disposition TEXT,
                dkim_result TEXT,
                spf_result TEXT,
                header_from TEXT,
                dkim_auth TEXT,  -- JSON array
                spf_auth TEXT,   -- JSON array
                FOREIGN KEY (report_id) REFERENCES reports (id)
            )
        ''')

        # Create indexes for better performance
        cursor.execute('CREATE INDEX IF NOT EXISTS idx_reports_domain ON reports (domain)')
        cursor.execute('CREATE INDEX IF NOT EXISTS idx_records_source_ip ON records (source_ip)')
        cursor.execute('CREATE INDEX IF NOT EXISTS idx_records_disposition ON records (disposition)')

        conn.commit()
        conn.close()

    def store_report(self, report_data):
        """Store parsed DMARC report data

        Returns:
            bool: True if report was stored, False if it was a duplicate
        """
        conn = sqlite3.connect(self.db_path)
        cursor = conn.cursor()

        try:
            metadata = report_data.get('metadata', {})
            policy = report_data.get('policy_published', {})
            records = report_data.get('records', [])

            # Check if report already exists
            cursor.execute('SELECT id FROM reports WHERE report_id = ?', (metadata.get('report_id'),))
            if cursor.fetchone():
                conn.close()
                return False  # Duplicate found

            # Insert report metadata
            cursor.execute('''
                INSERT INTO reports (
                    org_name, email, report_id, date_begin, date_end,
                    domain, policy_p, policy_sp, policy_pct, policy_adkim, policy_aspf
                ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
            ''', (
                metadata.get('org_name'),
                metadata.get('email'),
                metadata.get('report_id'),
                metadata.get('date_begin'),
                metadata.get('date_end'),
                policy.get('domain'),
                policy.get('p'),
                policy.get('sp'),
                policy.get('pct'),
                policy.get('adkim'),
                policy.get('aspf')
            ))

            report_id = cursor.lastrowid

            # Insert records
            for record in records:
                cursor.execute('''
                    INSERT INTO records (
                        report_id, source_ip, count, disposition, dkim_result, spf_result,
                        header_from, dkim_auth, spf_auth
                    ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)
                ''', (
                    report_id,
                    record.get('source_ip'),
                    record.get('count'),
                    record.get('disposition'),
                    record.get('dkim_result'),
                    record.get('spf_result'),
                    record.get('header_from'),
                    json.dumps(record.get('dkim_auth', [])),
                    json.dumps(record.get('spf_auth', []))
                ))

            conn.commit()
            return True  # Successfully stored

        except Exception as e:
            conn.rollback()
            raise
        finally:
            conn.close()

    def get_summary_stats(self, date_filter=None):
        """Get summary statistics"""
        conn = sqlite3.connect(self.db_path)
        cursor = conn.cursor()

        stats = {}

        # Build date filter conditions
        date_where, date_params = self._build_date_filter(date_filter)
        reports_where = f"WHERE {date_where}" if date_where else ""
        join_where = f"JOIN reports r ON r.id = rec.report_id WHERE {date_where}" if date_where else "JOIN reports r ON r.id = rec.report_id"

        # Total reports
        cursor.execute(f'SELECT COUNT(*) FROM reports {reports_where}', date_params)
        stats['total_reports'] = cursor.fetchone()[0]

        # Total messages
        cursor.execute(f'SELECT SUM(rec.count) FROM records rec {join_where}', date_params)
        result = cursor.fetchone()[0]
        stats['total_messages'] = result if result else 0

        # Messages by disposition
        cursor.execute(f'''
            SELECT disposition, SUM(rec.count) as total
            FROM records rec
            {join_where}
            GROUP BY disposition
            ORDER BY total DESC
        ''', date_params)
        stats['by_disposition'] = cursor.fetchall()

        # Messages by domain
        cursor.execute(f'''
            SELECT r.domain, SUM(rec.count) as total
            FROM reports r
            JOIN records rec ON r.id = rec.report_id
            {"WHERE " + date_where if date_where else ""}
            GROUP BY r.domain
            ORDER BY total DESC
            LIMIT 10
        ''', date_params)
        stats['by_domain'] = cursor.fetchall()

        # Messages by source IP (top 10)
        cursor.execute(f'''
            SELECT source_ip, SUM(rec.count) as total
            FROM records rec
            {join_where}
            GROUP BY source_ip
            ORDER BY total DESC
            LIMIT 10
        ''', date_params)
        stats['by_source_ip'] = cursor.fetchall()

        # DKIM/SPF results
        dkim_where = f"{join_where} AND rec.dkim_result IS NOT NULL" if join_where else "JOIN reports r ON r.id = rec.report_id WHERE rec.dkim_result IS NOT NULL"
        cursor.execute(f'''
            SELECT dkim_result, COUNT(*) as count
            FROM records rec
            {dkim_where}
            GROUP BY dkim_result
        ''', date_params)
        stats['dkim_results'] = cursor.fetchall()

        spf_where = f"{join_where} AND rec.spf_result IS NOT NULL" if join_where else "JOIN reports r ON r.id = rec.report_id WHERE rec.spf_result IS NOT NULL"
        cursor.execute(f'''
            SELECT spf_result, COUNT(*) as count
            FROM records rec
            {spf_where}
            GROUP BY spf_result
        ''', date_params)
        stats['spf_results'] = cursor.fetchall()

        conn.close()
        return stats

    def get_detailed_records(self, limit=100):
        """Get detailed record view"""
        conn = sqlite3.connect(self.db_path)
        cursor = conn.cursor()

        cursor.execute('''
            SELECT
                r.domain,
                r.org_name,
                rec.source_ip,
                rec.count,
                rec.disposition,
                rec.dkim_result,
                rec.spf_result,
                rec.header_from,
                r.date_begin,
                r.date_end
            FROM reports r
            JOIN records rec ON r.id = rec.report_id
            ORDER BY rec.count DESC
            LIMIT ?
        ''', (limit,))

        records = cursor.fetchall()
        conn.close()
        return records

    def get_failure_analysis(self):
        """Get detailed failure analysis"""
        conn = sqlite3.connect(self.db_path)
        cursor = conn.cursor()

        analysis = {}

        # Authentication failure breakdown
        cursor.execute('''
            SELECT
                CASE
                    WHEN dkim_result = 'fail' AND spf_result = 'fail' THEN 'Both DKIM & SPF Failed'
                    WHEN dkim_result = 'fail' AND spf_result != 'fail' THEN 'DKIM Failed Only'
                    WHEN dkim_result != 'fail' AND spf_result = 'fail' THEN 'SPF Failed Only'
                    ELSE 'Both Passed'
                END as failure_type,
                SUM(count) as total_count,
                COUNT(*) as record_count
            FROM records
            GROUP BY failure_type
            ORDER BY total_count DESC
        ''')
        analysis['auth_failure_breakdown'] = cursor.fetchall()

        # Failures by source IP
        cursor.execute('''
            SELECT source_ip, SUM(count) as total_count
            FROM records
            WHERE dkim_result = 'fail' OR spf_result = 'fail'
            GROUP BY source_ip
            ORDER BY total_count DESC
            LIMIT 10
        ''')
        analysis['failures_by_ip'] = cursor.fetchall()

        # Failures by domain
        cursor.execute('''
            SELECT r.domain, SUM(rec.count) as total_count
            FROM reports r
            JOIN records rec ON r.id = rec.report_id
            WHERE rec.dkim_result = 'fail' OR rec.spf_result = 'fail'
            GROUP BY r.domain
            ORDER BY total_count DESC
        ''')
        analysis['failures_by_domain'] = cursor.fetchall()

        # Failures by reporting provider
        cursor.execute('''
            SELECT r.org_name, SUM(rec.count) as total_count
            FROM reports r
            JOIN records rec ON r.id = rec.report_id
            WHERE rec.dkim_result = 'fail' OR rec.spf_result = 'fail'
            GROUP BY r.org_name
            ORDER BY total_count DESC
        ''')
        analysis['failures_by_provider'] = cursor.fetchall()

        # Detailed provider breakdown with dates
        cursor.execute('''
            SELECT
                r.org_name,
                DATE(r.date_begin) as report_date,
                SUM(rec.count) as failed_count,
                COUNT(DISTINCT rec.source_ip) as unique_ips
            FROM reports r
            JOIN records rec ON r.id = rec.report_id
            WHERE rec.dkim_result = 'fail' OR rec.spf_result = 'fail'
            GROUP BY r.org_name, DATE(r.date_begin)
            ORDER BY report_date DESC, failed_count DESC
        ''')
        analysis['provider_timeline'] = cursor.fetchall()

        # Policy actions on failures
        cursor.execute('''
            SELECT disposition, SUM(count) as total_count
            FROM records
            WHERE dkim_result = 'fail' OR spf_result = 'fail'
            GROUP BY disposition
            ORDER BY total_count DESC
        ''')
        analysis['failure_dispositions'] = cursor.fetchall()

        # Detailed failure records
        cursor.execute('''
            SELECT
                r.domain,
                rec.source_ip,
                rec.count,
                rec.disposition,
                rec.dkim_result,
                rec.spf_result,
                rec.header_from,
                r.date_begin,
                r.org_name,
                r.email as reporter_email
            FROM reports r
            JOIN records rec ON r.id = rec.report_id
            WHERE rec.dkim_result = 'fail' OR rec.spf_result = 'fail'
            ORDER BY rec.count DESC
            LIMIT 50
        ''')
        analysis['detailed_failures'] = cursor.fetchall()

        conn.close()
        return analysis

    def _build_date_filter(self, date_filter):
        """Build WHERE clause and parameters for date filtering"""
        if not date_filter:
            return "", []

        conditions = []
        params = []

        if 'date_from' in date_filter:
            conditions.append("DATE(date_begin) >= ?")
            params.append(date_filter['date_from'].strftime('%Y-%m-%d'))

        if 'date_to' in date_filter:
            conditions.append("DATE(date_begin) <= ?")
            params.append(date_filter['date_to'].strftime('%Y-%m-%d'))

        where_clause = " AND ".join(conditions) if conditions else ""
        return where_clause, params

    def get_timeline_stats(self, date_filter=None):
        """Get daily breakdown statistics"""
        conn = sqlite3.connect(self.db_path)
        cursor = conn.cursor()

        date_where, date_params = self._build_date_filter(date_filter)
        where_clause = f"WHERE {date_where}" if date_where else ""

        cursor.execute(f'''
            SELECT
                DATE(r.date_begin) as report_date,
                SUM(rec.count) as total_messages,
                SUM(CASE WHEN rec.dkim_result = 'fail' OR rec.spf_result = 'fail' THEN rec.count ELSE 0 END) as failed_messages,
                COUNT(DISTINCT r.org_name) as reporters
            FROM reports r
            JOIN records rec ON r.id = rec.report_id
            {where_clause}
            GROUP BY DATE(r.date_begin)
            ORDER BY report_date
        ''', date_params)

        timeline = cursor.fetchall()
        conn.close()
        return timeline