package app

import (
	"context"
	"encoding/json"
	"fmt"
	"sort"
	"strings"

	"github.com/Apale7/opencode-provider-switch/internal/config"
)

func (s *Service) ExportConfig(ctx context.Context) (ConfigExportView, error) {
	_ = ctx
	cfg, err := s.loadConfig()
	if err != nil {
		return ConfigExportView{}, err
	}
	content, err := marshalConfigContent(cfg)
	if err != nil {
		return ConfigExportView{}, err
	}
	return ConfigExportView{ConfigPath: cfg.Path(), Content: content}, nil
}

func (s *Service) ImportConfig(ctx context.Context, in ConfigImportInput) (ConfigImportResult, error) {
	_ = ctx
	content := strings.TrimSpace(in.Content)
	if content == "" {
		return ConfigImportResult{}, fmt.Errorf("config content is required")
	}

	imported := config.Default()
	if err := json.Unmarshal([]byte(content), imported); err != nil {
		return ConfigImportResult{}, fmt.Errorf("parse config: %w", err)
	}
	if imported.Server.Host == "" {
		imported.Server.Host = "127.0.0.1"
	}
	if imported.Server.Port == 0 {
		imported.Server.Port = 9982
	}
	if imported.Server.APIKey == "" {
		imported.Server.APIKey = config.DefaultLocalAPIKey
	}
	if errs := imported.Validate(); len(errs) > 0 {
		return ConfigImportResult{}, errs[0]
	}

	cfg, err := s.loadConfig()
	if err != nil {
		return ConfigImportResult{}, err
	}
	cfg.Server = imported.Server
	cfg.Desktop = imported.Desktop
	cfg.Providers = append([]config.Provider(nil), imported.Providers...)
	cfg.Aliases = append([]config.Alias(nil), imported.Aliases...)
	if err := cfg.Save(); err != nil {
		return ConfigImportResult{}, err
	}

	result := ConfigImportResult{ConfigPath: cfg.Path()}
	if s.currentProxyStatus(proxyBindAddress(cfg)).Running {
		result.Warnings = append(result.Warnings, "proxy is still running with the previous in-memory config; restart it to apply imported settings")
	}
	return result, nil
}

func marshalConfigContent(cfg *config.Config) (string, error) {
	providers := append([]config.Provider(nil), cfg.Providers...)
	sort.Slice(providers, func(i, j int) bool { return providers[i].ID < providers[j].ID })
	aliases := append([]config.Alias(nil), cfg.Aliases...)
	sort.Slice(aliases, func(i, j int) bool { return aliases[i].Alias < aliases[j].Alias })
	snapshot := struct {
		Server    config.Server     `json:"server"`
		Desktop   config.Desktop    `json:"desktop,omitempty"`
		Providers []config.Provider `json:"providers"`
		Aliases   []config.Alias    `json:"aliases"`
	}{
		Server:    cfg.Server,
		Desktop:   cfg.Desktop,
		Providers: providers,
		Aliases:   aliases,
	}
	data, err := json.MarshalIndent(snapshot, "", "  ")
	if err != nil {
		return "", fmt.Errorf("marshal config: %w", err)
	}
	return string(append(data, '\n')), nil
}