package sqlite

import (
	"context"
	"database/sql"
	"encoding/json"
	"fmt"
	"time"

	"switchboard-core/models"
	"switchboard-core/store"
)

// ── ConnectionStore (v0.38.1) ────────────────────────

type ConnectionStore struct{}

func NewConnectionStore() *ConnectionStore { return &ConnectionStore{} }

const connCols = `id, type, package_id, scope, owner_id, name, config, is_active, created_at, updated_at`

func (s *ConnectionStore) Create(ctx context.Context, conn *models.ExtConnection) error {
	conn.ID = store.NewID()
	now := time.Now().UTC()
	conn.CreatedAt = now
	conn.UpdatedAt = now
	_, err := DB.ExecContext(ctx, `
		INSERT INTO ext_connections (id, type, package_id, scope, owner_id, name, config, is_active,
			created_at, updated_at)
		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
		conn.ID, conn.Type, conn.PackageID, conn.Scope, conn.OwnerID,
		conn.Name, ToJSON(conn.Config), conn.IsActive,
		now.Format(timeFmt), now.Format(timeFmt),
	)
	return err
}

func (s *ConnectionStore) GetByID(ctx context.Context, id string) (*models.ExtConnection, error) {
	row := DB.QueryRowContext(ctx,
		fmt.Sprintf("SELECT %s FROM ext_connections WHERE id = ?", connCols), id)
	return scanConnection(row)
}

func (s *ConnectionStore) Update(ctx context.Context, id string, patch models.ExtConnectionPatch) error {
	b := NewUpdate("ext_connections")
	if patch.Name != nil {
		b.Set("name", *patch.Name)
	}
	if patch.Config != nil {
		b.SetJSON("config", patch.Config)
	}
	if patch.IsActive != nil {
		b.Set("is_active", *patch.IsActive)
	}
	if !b.HasSets() {
		return nil
	}
	b.Where("id", id)
	_, err := b.Exec(DB)
	return err
}

func (s *ConnectionStore) Delete(ctx context.Context, id string) error {
	_, err := DB.ExecContext(ctx, "DELETE FROM ext_connections WHERE id = ?", id)
	return err
}

// ── Scoped Queries ─────────────────────────────────

func (s *ConnectionStore) ListGlobal(ctx context.Context) ([]models.ExtConnection, error) {
	return s.listByScope(ctx, models.ScopeGlobal, "")
}

func (s *ConnectionStore) ListForTeam(ctx context.Context, teamID string) ([]models.ExtConnection, error) {
	return s.listByScope(ctx, models.ScopeTeam, teamID)
}

func (s *ConnectionStore) ListForUser(ctx context.Context, userID string) ([]models.ExtConnection, error) {
	return s.listByScope(ctx, models.ScopePersonal, userID)
}

// ── Resolution ─────────────────────────────────────

func (s *ConnectionStore) Resolve(ctx context.Context, userID, connType, name string) (*models.ExtConnection, error) {
	q := fmt.Sprintf(`
		SELECT %s FROM ext_connections
		WHERE type = ? AND is_active = 1
		  AND (
			(scope = 'personal' AND owner_id = ?)
			OR (scope = 'team' AND owner_id IN (
				SELECT team_id FROM team_members WHERE user_id = ?
			))
			OR (scope = 'global')
		  )`, connCols)
	args := []any{connType, userID, userID}
	if name != "" {
		q += " AND name = ?"
		args = append(args, name)
	}
	// Priority: personal(0) → team(1) → global(2).
	q += " ORDER BY CASE scope WHEN 'personal' THEN 0 WHEN 'team' THEN 1 ELSE 2 END, created_at ASC LIMIT 1"
	row := DB.QueryRowContext(ctx, q, args...)
	return scanConnection(row)
}

func (s *ConnectionStore) ResolveAll(ctx context.Context, userID, connType string) ([]models.ExtConnection, error) {
	rows, err := DB.QueryContext(ctx, fmt.Sprintf(`
		SELECT %s FROM ext_connections
		WHERE type = ? AND is_active = 1
		  AND (
			(scope = 'personal' AND owner_id = ?)
			OR (scope = 'team' AND owner_id IN (
				SELECT team_id FROM team_members WHERE user_id = ?
			))
			OR (scope = 'global')
		  )
		ORDER BY scope ASC, name ASC`, connCols), connType, userID, userID)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	return scanConnections(rows)
}

func (s *ConnectionStore) ListAccessible(ctx context.Context, userID string) ([]models.ExtConnection, error) {
	rows, err := DB.QueryContext(ctx, fmt.Sprintf(`
		SELECT %s FROM ext_connections
		WHERE is_active = 1
		  AND (
			(scope = 'personal' AND owner_id = ?)
			OR (scope = 'team' AND owner_id IN (
				SELECT team_id FROM team_members WHERE user_id = ?
			))
			OR (scope = 'global')
		  )
		ORDER BY type ASC, scope ASC, name ASC`, connCols), userID, userID)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	return scanConnections(rows)
}

func (s *ConnectionStore) DeleteByIDAndScope(ctx context.Context, id, scope, ownerID string) (int64, error) {
	res, err := DB.ExecContext(ctx,
		`DELETE FROM ext_connections WHERE id = ? AND scope = ? AND owner_id = ?`,
		id, scope, ownerID)
	if err != nil {
		return 0, err
	}
	return res.RowsAffected()
}

// ── Internal ───────────────────────────────────────

func (s *ConnectionStore) listByScope(ctx context.Context, scope, ownerID string) ([]models.ExtConnection, error) {
	var rows *sql.Rows
	var err error
	if scope == models.ScopeGlobal {
		rows, err = DB.QueryContext(ctx,
			fmt.Sprintf("SELECT %s FROM ext_connections WHERE scope = ? ORDER BY type, name", connCols),
			scope)
	} else {
		rows, err = DB.QueryContext(ctx,
			fmt.Sprintf("SELECT %s FROM ext_connections WHERE scope = ? AND owner_id = ? ORDER BY type, name", connCols),
			scope, ownerID)
	}
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	return scanConnections(rows)
}

func scanConnection(row *sql.Row) (*models.ExtConnection, error) {
	var c models.ExtConnection
	var configJSON []byte
	err := row.Scan(
		&c.ID, &c.Type, &c.PackageID, &c.Scope, &c.OwnerID,
		&c.Name, &configJSON, &c.IsActive, st(&c.CreatedAt), st(&c.UpdatedAt),
	)
	if err != nil {
		return nil, err
	}
	json.Unmarshal(configJSON, &c.Config)
	return &c, nil
}

func scanConnections(rows *sql.Rows) ([]models.ExtConnection, error) {
	var result []models.ExtConnection
	for rows.Next() {
		var c models.ExtConnection
		var configJSON []byte
		err := rows.Scan(
			&c.ID, &c.Type, &c.PackageID, &c.Scope, &c.OwnerID,
			&c.Name, &configJSON, &c.IsActive, st(&c.CreatedAt), st(&c.UpdatedAt),
		)
		if err != nil {
			return nil, err
		}
		json.Unmarshal(configJSON, &c.Config)
		result = append(result, c)
	}
	return result, rows.Err()
}