package fingerprint

import (
	"context"

	"github.com/go-task/task/v3/internal/logger"
	"github.com/go-task/task/v3/taskfile/ast"
)

type (
	CheckerOption func(*CheckerConfig)
	CheckerConfig struct {
		method         string
		dry            bool
		tempDir        string
		logger         *logger.Logger
		statusChecker  StatusCheckable
		sourcesChecker SourcesCheckable
	}
)

func WithMethod(method string) CheckerOption {
	return func(config *CheckerConfig) {
		config.method = method
	}
}

func WithDry(dry bool) CheckerOption {
	return func(config *CheckerConfig) {
		config.dry = dry
	}
}

func WithTempDir(tempDir string) CheckerOption {
	return func(config *CheckerConfig) {
		config.tempDir = tempDir
	}
}

func WithLogger(logger *logger.Logger) CheckerOption {
	return func(config *CheckerConfig) {
		config.logger = logger
	}
}

func WithStatusChecker(checker StatusCheckable) CheckerOption {
	return func(config *CheckerConfig) {
		config.statusChecker = checker
	}
}

func WithSourcesChecker(checker SourcesCheckable) CheckerOption {
	return func(config *CheckerConfig) {
		config.sourcesChecker = checker
	}
}

func IsTaskUpToDate(
	ctx context.Context,
	t *ast.Task,
	opts ...CheckerOption,
) (bool, error) {
	var statusUpToDate bool
	var sourcesUpToDate bool
	var err error

	// Default config
	config := &CheckerConfig{
		method:         "none",
		tempDir:        "",
		dry:            false,
		logger:         nil,
		statusChecker:  nil,
		sourcesChecker: nil,
	}

	// Apply functional options
	for _, opt := range opts {
		opt(config)
	}

	// If no status checker was given, set up the default one
	if config.statusChecker == nil {
		config.statusChecker = NewStatusChecker(config.logger)
	}

	// If no sources checker was given, set up the default one
	if config.sourcesChecker == nil {
		config.sourcesChecker, err = NewSourcesChecker(config.method, config.tempDir, config.dry)
		if err != nil {
			return false, err
		}
	}

	statusIsSet := len(t.Status) != 0
	sourcesIsSet := len(t.Sources) != 0

	// If status is set, check if it is up-to-date
	if statusIsSet {
		statusUpToDate, err = config.statusChecker.IsUpToDate(ctx, t)
		if err != nil {
			return false, err
		}
	}

	// If sources is set, check if they are up-to-date
	if sourcesIsSet {
		sourcesUpToDate, err = config.sourcesChecker.IsUpToDate(t)
		if err != nil {
			return false, err
		}
	}

	// If both status and sources are set, the task is up-to-date if both are up-to-date
	if statusIsSet && sourcesIsSet {
		return statusUpToDate && sourcesUpToDate, nil
	}

	// If only status is set, the task is up-to-date if the status is up-to-date
	if statusIsSet {
		return statusUpToDate, nil
	}

	// If only sources is set, the task is up-to-date if the sources are up-to-date
	if sourcesIsSet {
		return sourcesUpToDate, nil
	}

	// If no status or sources are set, the task should always run
	// i.e. it is never considered "up-to-date"
	return false, nil
}