package main

import (
	"context"
	"fmt"
	"log/slog"
	"strconv"
	"strings"

	"git.loyso.art/frx/kurious/internal/common/client/sravni"
	"git.loyso.art/frx/kurious/internal/common/errors"
	"git.loyso.art/frx/kurious/internal/common/xslices"

	"github.com/teris-io/cli"
)

const (
	learningTypeOptName          = "learning-type"
	courseThematicOptName        = "course-thematic"
	learningTypeSelectionOptName = "learning-selection"
)

func setupAPICommand(ctx context.Context) cli.Command {
	learningTypeOpt := cli.NewOption(learningTypeOptName, "Specify learning type").
		WithType(cli.TypeString)
	courseThematic := cli.NewOption(courseThematicOptName, "Specify course thematic").
		WithType(cli.TypeString)
	learningSelectionOpt := cli.NewOption(learningTypeSelectionOptName, "Specify learning type selection").
		WithType(cli.TypeString)

	apiEducationListProducts := buildCLICommand(func() cli.Command {
		return cli.NewCommand("list_products", "List products by some filters").
			WithOption(learningTypeOpt).
			WithOption(courseThematic).
			WithOption(learningSelectionOpt).
			WithOption(limitOption).
			WithOption(offsetOption).
			WithAction(newListProductAction(ctx))
	})
	apiEducationFilterCount := buildCLICommand(func() cli.Command {
		return cli.NewCommand("filter_count", "Loads counts of returned entities").
			WithOption(learningTypeOpt).
			WithOption(courseThematic).
			WithOption(learningSelectionOpt).
			WithAction(newProductsFilterCountAction(ctx))
	})

	apiEducation := cli.NewCommand("education", "Education related category").
		WithCommand(apiEducationListProducts).
		WithCommand(apiEducationFilterCount)

	return cli.NewCommand("api", "Interaction with API").
		WithCommand(apiEducation)
}

type action interface {
	context() context.Context
	parse(args []string, options map[string]string) error
	handle() error
}

func asCLIAction(a action) cli.Action {
	return func(args []string, options map[string]string) int {
		ctx := a.context()
		log := makeLogger(options)
		err := a.parse(args, options)
		if err != nil {
			log.ErrorContext(ctx, "unable to parse args and opts", slog.Any("err", err))
			return -1
		}
		err = a.handle()
		if err != nil {
			log.ErrorContext(ctx, "unable to handle action", slog.Any("err", err))
			return -1
		}

		return 0
	}
}

type listProductsActionParams struct {
	learningType          string
	courseThematic        string
	learningSelectionType string
	limit                 int
	offset                int
}

type listProductsAction struct {
	*baseAction

	client sravni.Client
	params listProductsActionParams
}

func newListProductAction(ctx context.Context) cli.Action {
	action := &listProductsAction{
		baseAction: newBaseAction(ctx),
	}

	return asCLIAction(action)
}

func (a *listProductsAction) parse(args []string, options map[string]string) error {
	err := a.baseAction.parse(args, options)
	if err != nil {
		return err
	}

	var ok bool

	a.params.learningType, ok = options[learningTypeOptName]
	if !ok {
		return errors.SimpleError(learningTypeOptName + " is empty")
	}

	a.params.courseThematic = options[courseThematicOptName]
	a.params.learningSelectionType = options[learningTypeSelectionOptName]

	if value, ok := options[limitOption.Key()]; ok {
		a.params.limit, _ = strconv.Atoi(value)
	}
	if value, ok := options[offsetOption.Key()]; ok {
		a.params.offset, _ = strconv.Atoi(value)
	}

	client, err := makeSravniClient(a.ctx, a.log, options)
	if err != nil {
		return fmt.Errorf("making sravni client: %w", err)
	}

	a.client = client

	return nil
}

func (a *listProductsAction) handle() error {
	params := sravni.ListEducationProductsParams{
		LearningType:     a.params.learningType,
		CoursesThematics: []string{a.params.courseThematic},
		Limit:            a.params.limit,
		Offset:           a.params.offset,
	}
	result, err := a.client.ListEducationalProducts(a.ctx, params)
	if err != nil {
		return fmt.Errorf("listing education products: %w", err)
	}

	a.log.InfoContext(a.ctx, "list education products result", slog.Any("result", result))

	return nil
}

type productsFilterCountActionParams struct {
	learningType          string
	courseThematic        []string
	learningSelectionType string
}

type productsFilterCountAction struct {
	*baseAction

	client sravni.Client
	params productsFilterCountActionParams
}

func newProductsFilterCountAction(ctx context.Context) cli.Action {
	action := &productsFilterCountAction{
		baseAction: newBaseAction(ctx),
	}

	return asCLIAction(action)
}

func (a *productsFilterCountAction) parse(args []string, options map[string]string) error {
	err := a.baseAction.parse(args, options)
	if err != nil {
		return err
	}

	var ok bool

	a.params.learningType, ok = options[learningTypeOptName]
	if !ok {
		return errors.SimpleError(learningTypeOptName + " is empty")
	}

	filterNotEmpty := func(value string) bool {
		return value != ""
	}
	a.params.courseThematic = xslices.Filter(
		strings.Split(options[courseThematicOptName], ","),
		filterNotEmpty,
	)
	a.params.learningSelectionType = options[learningTypeSelectionOptName]

	client, err := makeSravniClient(a.ctx, a.log, options)
	if err != nil {
		return fmt.Errorf("making sravni client: %w", err)
	}

	a.client = client

	return nil
}

func (a *productsFilterCountAction) handle() error {
	params := sravni.ListEducationProductsParams{
		LearningType:     a.params.learningType,
		CoursesThematics: a.params.courseThematic,
	}
	result, err := a.client.ListEducationalProductsFilterCount(a.ctx, params)
	if err != nil {
		return fmt.Errorf("listing education products: %w", err)
	}

	a.log.InfoContext(a.ctx, "list education products result", slog.Any("result", result))

	return nil
}