package core

import (
	"context"
	"encoding/json"
	"fmt"
	"log/slog"
	"path/filepath"

	aptclone "github.com/syonad/clonepack/internal/clone/apt"
	rpmclone "github.com/syonad/clonepack/internal/clone/rpm"
	"github.com/syonad/clonepack/internal/store"
)

var validTypes = map[string]bool{"apt": true, "rpm": true, "docker": true, "binary": true}

type RepoService struct {
	store   store.RepoStore
	dataDir string
}

func NewRepoService(s store.RepoStore, dataDir string) *RepoService {
	return &RepoService{store: s, dataDir: dataDir}
}

var validSyncModes = map[string]bool{"auto": true, "manual": true}

type CreateRepoInput struct {
	Name             string   `json:"name"`
	Type             string   `json:"type"`
	SourceURL        string   `json:"source_url"`
	SyncMode         string   `json:"sync_mode"`
	AptSuite         string   `json:"apt_suite,omitempty"`
	AptComponents    []string `json:"apt_components,omitempty"`
	AptArchitectures []string `json:"apt_architectures,omitempty"`
}

func (s *RepoService) Create(ctx context.Context, in CreateRepoInput) (*store.Repo, error) {
	if in.Name == "" {
		return nil, fmt.Errorf("name is required")
	}
	if !validTypes[in.Type] {
		return nil, fmt.Errorf("invalid type: %s (must be apt, rpm, docker, or binary)", in.Type)
	}
	if in.SourceURL == "" {
		return nil, fmt.Errorf("source_url is required")
	}
	if in.SyncMode == "" {
		in.SyncMode = "auto"
	} else if !validSyncModes[in.SyncMode] {
		return nil, fmt.Errorf("invalid sync_mode: %s (must be auto or manual)", in.SyncMode)
	}

	var configJSON string
	if in.Type == "apt" {
		if in.AptSuite == "" {
			return nil, fmt.Errorf("apt_suite is required for apt repositories")
		}
		if len(in.AptComponents) == 0 {
			in.AptComponents = []string{"main"}
		}
		if len(in.AptArchitectures) == 0 {
			in.AptArchitectures = []string{"amd64"}
		}
		cfg := aptclone.Config{
			Suite:         in.AptSuite,
			Components:    in.AptComponents,
			Architectures: in.AptArchitectures,
		}
		b, err := json.Marshal(cfg)
		if err != nil {
			return nil, fmt.Errorf("marshal apt config: %w", err)
		}
		configJSON = string(b)
	}

	r := &store.Repo{Name: in.Name, Type: in.Type, SourceURL: in.SourceURL, SyncMode: in.SyncMode, Config: configJSON}
	id, err := s.store.CreateRepo(ctx, r)
	if err != nil {
		return nil, err
	}
	repo, err := s.store.GetRepo(ctx, id)
	if err != nil {
		return nil, err
	}
	s.initStorage(repo)
	return repo, nil
}

func (s *RepoService) initStorage(repo *store.Repo) {
	localDir := filepath.Join(s.dataDir, "repos", fmt.Sprintf("%d", repo.ID), repo.Type)
	switch repo.Type {
	case "rpm":
		if err := rpmclone.InitEmptyRepo(localDir); err != nil {
			slog.Warn("init storage failed", "repo_id", repo.ID, "error", err)
		}
	case "apt":
		var cfg aptclone.Config
		if err := json.Unmarshal([]byte(repo.Config), &cfg); err != nil {
			slog.Warn("init storage: parse config failed", "repo_id", repo.ID, "error", err)
			return
		}
		if err := aptclone.InitEmptyRepo(localDir, cfg); err != nil {
			slog.Warn("init storage failed", "repo_id", repo.ID, "error", err)
		}
	}
}

type UpdateRepoInput struct {
	SourceURL        *string
	SyncMode         *string
	AptSuite         *string
	AptComponents    []string
	AptArchitectures []string
}

func (s *RepoService) Update(ctx context.Context, id int64, in UpdateRepoInput) (*store.Repo, error) {
	repo, err := s.store.GetRepo(ctx, id)
	if err != nil {
		return nil, err
	}

	if in.SourceURL != nil {
		if *in.SourceURL == "" {
			return nil, fmt.Errorf("source_url cannot be empty")
		}
		repo.SourceURL = *in.SourceURL
	}
	if in.SyncMode != nil {
		if !validSyncModes[*in.SyncMode] {
			return nil, fmt.Errorf("invalid sync_mode: %s (must be auto or manual)", *in.SyncMode)
		}
		repo.SyncMode = *in.SyncMode
	}

	if repo.Type == "apt" && (in.AptSuite != nil || in.AptComponents != nil || in.AptArchitectures != nil) {
		var cfg aptclone.Config
		if repo.Config != "" {
			if err := json.Unmarshal([]byte(repo.Config), &cfg); err != nil {
				return nil, fmt.Errorf("parse existing apt config: %w", err)
			}
		}
		if in.AptSuite != nil {
			if *in.AptSuite == "" {
				return nil, fmt.Errorf("apt_suite cannot be empty")
			}
			cfg.Suite = *in.AptSuite
		}
		if in.AptComponents != nil {
			cfg.Components = in.AptComponents
		}
		if in.AptArchitectures != nil {
			cfg.Architectures = in.AptArchitectures
		}
		b, err := json.Marshal(cfg)
		if err != nil {
			return nil, fmt.Errorf("marshal apt config: %w", err)
		}
		repo.Config = string(b)
	} else if repo.Type != "apt" && (in.AptSuite != nil || in.AptComponents != nil || in.AptArchitectures != nil) {
		return nil, fmt.Errorf("apt fields only apply to apt repositories")
	}

	if err := s.store.UpdateRepo(ctx, id, repo.SourceURL, repo.SyncMode, repo.Config); err != nil {
		return nil, err
	}
	return s.store.GetRepo(ctx, id)
}

func (s *RepoService) List(ctx context.Context) ([]store.Repo, error) {
	return s.store.ListRepos(ctx)
}

func (s *RepoService) Get(ctx context.Context, id int64) (*store.Repo, error) {
	return s.store.GetRepo(ctx, id)
}

func (s *RepoService) GetByName(ctx context.Context, name string) (*store.Repo, error) {
	return s.store.GetRepoByName(ctx, name)
}

func (s *RepoService) Delete(ctx context.Context, id int64) error {
	return s.store.DeleteRepo(ctx, id)
}