package cmd

import (
	"fmt"
	"os"

	"git.jnss.me/joakim/opal/internal/engine"
	"github.com/spf13/cobra"
)

var doneCmd = &cobra.Command{
	Use:   "done [filter...]",
	Short: "Mark tasks as completed",
	Long: `Mark one or more tasks as completed.

Examples:
  opal done 1              # Complete task with display ID 1
  opal 1 done              # Flexible syntax (same as above)
  opal done +urgent        # Complete all urgent tasks
  opal +urgent done        # Flexible syntax (same as above)
  opal done project:backend`,
	Run: func(cmd *cobra.Command, args []string) {
		parsed := getParsedArgs(cmd)
		if err := completeTasks(parsed.Filters); err != nil {
			fmt.Fprintf(os.Stderr, "Error: %v\n", err)
			os.Exit(1)
		}
	},
}

func completeTasks(args []string) error {
	// Parse filter
	filter, err := engine.ParseFilter(args)
	if err != nil {
		return fmt.Errorf("failed to parse filter: %w", err)
	}

	// Load working set to resolve IDs
	ws, err := engine.LoadWorkingSet()
	if err != nil {
		return fmt.Errorf("failed to load working set: %w", err)
	}

	// Get matching tasks
	var tasks []*engine.Task

	if len(filter.IDs) > 0 {
		// Resolve display IDs
		for _, id := range filter.IDs {
			task, err := ws.GetTaskByDisplayID(id)
			if err != nil {
				return err
			}
			tasks = append(tasks, task)
		}
	} else {
		// Use filter to get tasks
		matched, err := engine.GetTasks(filter)
		if err != nil {
			return fmt.Errorf("failed to get tasks: %w", err)
		}
		tasks = matched
	}

	if len(tasks) == 0 {
		return fmt.Errorf("no tasks matched filter")
	}

	if len(tasks) > 1 {
		fmt.Print(engine.FormatTaskConfirmList("complete", tasks, ws))
		fmt.Printf("Proceed? (y/N): ")
		var confirm string
		fmt.Scanln(&confirm)
		if confirm != "y" && confirm != "Y" {
			fmt.Println("Cancelled.")
			return nil
		}
	}

	// Complete tasks
	completed := 0
	for _, task := range tasks {
		if _, err := task.Complete(); err != nil {
			fmt.Fprintf(os.Stderr, "Warning: failed to complete task %s: %v\n", task.UUID, err)
		} else {
			completed++
		}
	}

	if len(tasks) == 1 {
		fmt.Printf("Completed task %s\n", engine.FormatTaskSummary(tasks[0], ws))
	} else {
		fmt.Printf("Completed %d task(s).\n", completed)
	}

	return nil
}