package cli

import (
	"encoding/json"
	"path/filepath"
	"strings"

	"git.eeqj.de/sneak/secret/internal/secret"
	"git.eeqj.de/sneak/secret/internal/vault"
	"github.com/spf13/afero"
	"github.com/spf13/cobra"
)

// getSecretNamesCompletionFunc returns a completion function that provides secret names
func getSecretNamesCompletionFunc(fs afero.Fs, stateDir string) func(
	cmd *cobra.Command, args []string, toComplete string,
) ([]string, cobra.ShellCompDirective) {
	return func(_ *cobra.Command, _ []string, toComplete string) ([]string, cobra.ShellCompDirective) {
		// Get current vault
		vlt, err := vault.GetCurrentVault(fs, stateDir)
		if err != nil {
			return nil, cobra.ShellCompDirectiveNoFileComp
		}

		// Get list of secrets
		secrets, err := vlt.ListSecrets()
		if err != nil {
			return nil, cobra.ShellCompDirectiveNoFileComp
		}

		// Filter secrets based on what user has typed
		var completions []string
		for _, secret := range secrets {
			if strings.HasPrefix(secret, toComplete) {
				completions = append(completions, secret)
			}
		}

		return completions, cobra.ShellCompDirectiveNoFileComp
	}
}

// getUnlockerIDsCompletionFunc returns a completion function that provides unlocker IDs
func getUnlockerIDsCompletionFunc(fs afero.Fs, stateDir string) func(
	cmd *cobra.Command, args []string, toComplete string,
) ([]string, cobra.ShellCompDirective) {
	return func(_ *cobra.Command, _ []string, toComplete string) ([]string, cobra.ShellCompDirective) {
		// Get current vault
		vlt, err := vault.GetCurrentVault(fs, stateDir)
		if err != nil {
			return nil, cobra.ShellCompDirectiveNoFileComp
		}

		// Get unlocker metadata list
		unlockerMetadataList, err := vlt.ListUnlockers()
		if err != nil {
			return nil, cobra.ShellCompDirectiveNoFileComp
		}

		// Get vault directory
		vaultDir, err := vlt.GetDirectory()
		if err != nil {
			return nil, cobra.ShellCompDirectiveNoFileComp
		}

		// Collect unlocker IDs
		var completions []string

		for _, metadata := range unlockerMetadataList {
			// Get the actual unlocker ID by creating the unlocker instance
			unlockersDir := filepath.Join(vaultDir, "unlockers.d")
			files, err := afero.ReadDir(fs, unlockersDir)
			if err != nil {
				continue
			}

			for _, file := range files {
				if !file.IsDir() {
					continue
				}

				unlockerDir := filepath.Join(unlockersDir, file.Name())
				metadataPath := filepath.Join(unlockerDir, "unlocker-metadata.json")

				// Check if this is the right unlocker by comparing metadata
				metadataBytes, err := afero.ReadFile(fs, metadataPath)
				if err != nil {
					continue
				}

				var diskMetadata secret.UnlockerMetadata
				if err := json.Unmarshal(metadataBytes, &diskMetadata); err != nil {
					continue
				}

				// Match by type and creation time
				if diskMetadata.Type == metadata.Type && diskMetadata.CreatedAt.Equal(metadata.CreatedAt) {
					// Create the appropriate unlocker instance
					var unlocker secret.Unlocker
					switch metadata.Type {
					case "passphrase":
						unlocker = secret.NewPassphraseUnlocker(fs, unlockerDir, diskMetadata)
					case "keychain":
						unlocker = secret.NewKeychainUnlocker(fs, unlockerDir, diskMetadata)
					case "pgp":
						unlocker = secret.NewPGPUnlocker(fs, unlockerDir, diskMetadata)
					}

					if unlocker != nil {
						id := unlocker.GetID()
						if strings.HasPrefix(id, toComplete) {
							completions = append(completions, id)
						}
					}

					break
				}
			}
		}

		return completions, cobra.ShellCompDirectiveNoFileComp
	}
}

// getVaultNamesCompletionFunc returns a completion function that provides vault names
func getVaultNamesCompletionFunc(fs afero.Fs, stateDir string) func(
	cmd *cobra.Command, args []string, toComplete string,
) ([]string, cobra.ShellCompDirective) {
	return func(_ *cobra.Command, _ []string, toComplete string) ([]string, cobra.ShellCompDirective) {
		vaults, err := vault.ListVaults(fs, stateDir)
		if err != nil {
			return nil, cobra.ShellCompDirectiveNoFileComp
		}

		var completions []string
		for _, v := range vaults {
			if strings.HasPrefix(v, toComplete) {
				completions = append(completions, v)
			}
		}

		return completions, cobra.ShellCompDirectiveNoFileComp
	}
}