package servicecatalog

import (
	"context"
	"errors"

	"github.com/google/uuid"
	"github.com/jackc/pgx/v5/pgxpool"
)

type Repository interface {
	List(ctx context.Context) ([]Service, error)
	Create(ctx context.Context, input CreateRequest) (Service, error)
	Update(ctx context.Context, serviceID uuid.UUID, input UpdateRequest) (Service, error)
	Delete(ctx context.Context, serviceID uuid.UUID) error
	ByIDs(ctx context.Context, ids []uuid.UUID) ([]Service, error)
}

type PGRepository struct {
	db *pgxpool.Pool
}

func NewPGRepository(db *pgxpool.Pool) *PGRepository {
	return &PGRepository{db: db}
}

func (r *PGRepository) List(ctx context.Context) ([]Service, error) {
	rows, err := r.db.Query(ctx, `
		select id, name, description, domain, host(upstream_ip), host(proxy_ip), ports, is_active
		from services
		where deleted_at is null
		order by name asc
	`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var items []Service
	for rows.Next() {
		var item Service
		if err := rows.Scan(&item.ID, &item.Name, &item.Description, &item.Domain, &item.UpstreamIP, &item.ProxyIP, &item.Ports, &item.IsActive); err != nil {
			return nil, err
		}
		items = append(items, item)
	}
	return items, rows.Err()
}

func (r *PGRepository) Create(ctx context.Context, input CreateRequest) (Service, error) {
	row := r.db.QueryRow(ctx, `
		insert into services (id, name, description, domain, upstream_ip, proxy_ip, ports, is_active)
		values ($1, $2, $3, $4, $5::inet, $6::inet, $7::integer[], coalesce($8, true))
		returning id, name, description, domain, host(upstream_ip), host(proxy_ip), ports, is_active
	`, uuid.New(), input.Name, input.Description, input.Domain, input.UpstreamIP, input.ProxyIP, normalizePorts(input.Ports), input.IsActive)

	var item Service
	err := row.Scan(&item.ID, &item.Name, &item.Description, &item.Domain, &item.UpstreamIP, &item.ProxyIP, &item.Ports, &item.IsActive)
	return item, err
}

func (r *PGRepository) Update(ctx context.Context, serviceID uuid.UUID, input UpdateRequest) (Service, error) {
	var ports *[]int
	if input.Ports != nil {
		normalized := normalizePorts(input.Ports)
		ports = &normalized
	}

	row := r.db.QueryRow(ctx, `
		update services
		set
			name = coalesce($2, name),
			description = coalesce($3, description),
			domain = coalesce($4, domain),
			upstream_ip = coalesce($5::inet, upstream_ip),
			proxy_ip = coalesce($6::inet, proxy_ip),
			ports = coalesce($7::integer[], ports),
			is_active = coalesce($8, is_active),
			updated_at = now()
		where id = $1 and deleted_at is null
		returning id, name, description, domain, host(upstream_ip), host(proxy_ip), ports, is_active
	`, serviceID, input.Name, input.Description, input.Domain, input.UpstreamIP, input.ProxyIP, ports, input.IsActive)

	var item Service
	err := row.Scan(&item.ID, &item.Name, &item.Description, &item.Domain, &item.UpstreamIP, &item.ProxyIP, &item.Ports, &item.IsActive)
	return item, err
}

func (r *PGRepository) Delete(ctx context.Context, serviceID uuid.UUID) error {
	_, err := r.db.Exec(ctx, `
		update services
		set deleted_at = now(), updated_at = now()
		where id = $1 and deleted_at is null
	`, serviceID)
	return err
}

func (r *PGRepository) ByIDs(ctx context.Context, ids []uuid.UUID) ([]Service, error) {
	if len(ids) == 0 {
		return nil, nil
	}

	rows, err := r.db.Query(ctx, `
		select id, name, description, domain, host(upstream_ip), host(proxy_ip), ports, is_active
		from services
		where deleted_at is null and id = any($1::uuid[])
		order by name asc
	`, ids)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var items []Service
	for rows.Next() {
		var item Service
		if err := rows.Scan(&item.ID, &item.Name, &item.Description, &item.Domain, &item.UpstreamIP, &item.ProxyIP, &item.Ports, &item.IsActive); err != nil {
			return nil, err
		}
		items = append(items, item)
	}
	if err := rows.Err(); err != nil {
		return nil, err
	}
	if len(items) == 0 {
		return nil, errors.New("services not found")
	}
	return items, nil
}

func normalizePorts(ports []int) []int {
	if len(ports) == 0 {
		return []int{80, 443}
	}

	seen := make(map[int]struct{}, len(ports))
	result := make([]int, 0, len(ports))
	for _, port := range ports {
		if port <= 0 {
			continue
		}
		if _, ok := seen[port]; ok {
			continue
		}
		seen[port] = struct{}{}
		result = append(result, port)
	}
	if len(result) == 0 {
		return []int{80, 443}
	}
	return result
}