package api

import (
	"encoding/json"
	"errors"
	"fmt"
	"net/http"
	"strings"

	"gardomatic.kleiax.de/internal/platform/validate"
	"gardomatic.kleiax.de/internal/storage"
)

type speciesInput struct {
	Global               bool            `json:"global"`
	Tags                 []string        `json:"tags"`
	CommonName           *string         `json:"common_name"`
	Cultivar             *string         `json:"cultivar"`
	BotanicalName        *string         `json:"botanical_name"`
	CategoryID           *int            `json:"category_id"`
	ClearCategoryID      bool            `json:"clear_category_id"`
	SunExposure          *string         `json:"sun_exposure"`
	SoilCondition        *string         `json:"soil_condition"`
	SoilReaction         *string         `json:"soil_reaction"`
	WinterProtection     *string         `json:"winter_protection"`
	SpacingCM            *int            `json:"spacing_cm"`
	HeightCM             *int            `json:"height_cm"`
	HeightCMFrom         *int            `json:"height_cm_from"`
	HeightCMTo           *int            `json:"height_cm_to"`
	WidthCMFrom          *int            `json:"width_cm_from"`
	WidthCMTo            *int            `json:"width_cm_to"`
	ClearHeightCMFrom    bool            `json:"clear_height_cm_from"`
	ClearHeightCMTo      bool            `json:"clear_height_cm_to"`
	ClearWidthCMFrom     bool            `json:"clear_width_cm_from"`
	ClearWidthCMTo       bool            `json:"clear_width_cm_to"`
	SowMonthFrom         *int            `json:"sow_month_from"`
	SowDayFrom           *int            `json:"sow_day_from"`
	ClearSowDayFrom      bool            `json:"clear_sow_day_from"`
	SowMonthTo           *int            `json:"sow_month_to"`
	SowDayTo             *int            `json:"sow_day_to"`
	ClearSowDayTo        bool            `json:"clear_sow_day_to"`
	PlantingMonthFrom    *int            `json:"planting_month_from"`
	PlantingDayFrom      *int            `json:"planting_day_from"`
	ClearPlantingDayFrom bool            `json:"clear_planting_day_from"`
	PlantingMonthTo      *int            `json:"planting_month_to"`
	PlantingDayTo        *int            `json:"planting_day_to"`
	ClearPlantingDayTo   bool            `json:"clear_planting_day_to"`
	HarvestMonthFrom     *int            `json:"harvest_month_from"`
	HarvestDayFrom       *int            `json:"harvest_day_from"`
	ClearHarvestDayFrom  bool            `json:"clear_harvest_day_from"`
	HarvestMonthTo       *int            `json:"harvest_month_to"`
	HarvestDayTo         *int            `json:"harvest_day_to"`
	ClearHarvestDayTo    bool            `json:"clear_harvest_day_to"`
	ClearSowRange        bool            `json:"clear_sow_range"`
	ClearPlantingRange   bool            `json:"clear_planting_range"`
	ClearHarvestRange    bool            `json:"clear_harvest_range"`
	Notes                *string         `json:"notes"`
	ImageData            *string         `json:"image_data"`
	ImageID              *int            `json:"image_id"`
	Attributes           json.RawMessage `json:"attributes"`
}

func (input speciesInput) apply(species *storage.Species) {
	assignTrimmed(input.CommonName, &species.CommonName)
	assignTrimmed(input.Cultivar, &species.Cultivar)
	assignTrimmed(input.BotanicalName, &species.BotanicalName)
	assignIntPointer(input.CategoryID, &species.CategoryID)
	if input.ClearCategoryID {
		species.CategoryID = nil
		species.Category = ""
	}
	assignTrimmed(input.Notes, &species.Notes)
	if input.ImageData != nil {
		species.ImageData = *input.ImageData
	}
	assignStringPointer(input.SunExposure, &species.SunExposure)
	assignStringPointer(input.SoilCondition, &species.SoilCondition)
	assignStringPointer(input.SoilReaction, &species.SoilReaction)
	assignStringPointer(input.WinterProtection, &species.WinterProtection)
	assignIntPointer(input.SpacingCM, &species.SpacingCM)
	assignIntPointer(input.HeightCMFrom, &species.HeightCMFrom)
	if input.HeightCMTo != nil {
		assignIntPointer(input.HeightCMTo, &species.HeightCMTo)
	} else {
		assignIntPointer(input.HeightCM, &species.HeightCMTo)
	}
	assignIntPointer(input.WidthCMFrom, &species.WidthCMFrom)
	assignIntPointer(input.WidthCMTo, &species.WidthCMTo)
	clearIntPointer(input.ClearHeightCMFrom, &species.HeightCMFrom)
	clearIntPointer(input.ClearHeightCMTo, &species.HeightCMTo)
	clearIntPointer(input.ClearWidthCMFrom, &species.WidthCMFrom)
	clearIntPointer(input.ClearWidthCMTo, &species.WidthCMTo)
	species.HeightCM = species.HeightCMTo
	assignIntPointer(input.SowMonthFrom, &species.SowMonthFrom)
	assignIntPointer(input.SowDayFrom, &species.SowDayFrom)
	assignIntPointer(input.SowMonthTo, &species.SowMonthTo)
	assignIntPointer(input.SowDayTo, &species.SowDayTo)
	assignIntPointer(input.PlantingMonthFrom, &species.PlantingMonthFrom)
	assignIntPointer(input.PlantingDayFrom, &species.PlantingDayFrom)
	assignIntPointer(input.PlantingMonthTo, &species.PlantingMonthTo)
	assignIntPointer(input.PlantingDayTo, &species.PlantingDayTo)
	assignIntPointer(input.HarvestMonthFrom, &species.HarvestMonthFrom)
	assignIntPointer(input.HarvestDayFrom, &species.HarvestDayFrom)
	assignIntPointer(input.HarvestMonthTo, &species.HarvestMonthTo)
	assignIntPointer(input.HarvestDayTo, &species.HarvestDayTo)
	if input.ClearSowRange {
		species.SowMonthFrom, species.SowDayFrom, species.SowMonthTo, species.SowDayTo = nil, nil, nil, nil
	}
	if input.ClearHarvestRange {
		species.HarvestMonthFrom, species.HarvestDayFrom, species.HarvestMonthTo, species.HarvestDayTo = nil, nil, nil, nil
	}
	if input.ClearPlantingRange {
		species.PlantingMonthFrom, species.PlantingDayFrom, species.PlantingMonthTo, species.PlantingDayTo = nil, nil, nil, nil
	}
	if input.ClearSowDayFrom {
		species.SowDayFrom = nil
	}
	if input.ClearSowDayTo {
		species.SowDayTo = nil
	}
	if input.ClearPlantingDayFrom {
		species.PlantingDayFrom = nil
	}
	if input.ClearPlantingDayTo {
		species.PlantingDayTo = nil
	}
	if input.ClearHarvestDayFrom {
		species.HarvestDayFrom = nil
	}
	if input.ClearHarvestDayTo {
		species.HarvestDayTo = nil
	}
	if len(input.Attributes) != 0 {
		species.Attributes = input.Attributes
	}
}

func assignTrimmed(input *string, destination *string) {
	if input != nil {
		*destination = strings.TrimSpace(*input)
	}
}

func assignStringPointer(input *string, destination **string) {
	if input != nil {
		value := strings.TrimSpace(*input)
		if value == "" {
			*destination = nil
		} else {
			*destination = &value
		}
	}
}

func assignIntPointer(input *int, destination **int) {
	if input != nil {
		*destination = input
	}
}

func clearIntPointer(clear bool, destination **int) {
	if clear {
		*destination = nil
	}
}

func (app *application) createSpeciesHandler(w http.ResponseWriter, r *http.Request) {
	gardenID, _ := app.readGardenIDParam(r)
	var input speciesInput
	if err := app.readJSON(w, r, &input); err != nil {
		app.badRequestResponse(w, r, err)
		return
	}
	member, _ := app.contextGetGardenMember(r)
	user, _ := app.contextGetAuthenticatedUser(r)
	if input.Global {
		if !user.Can(storage.ApplicationPermissionGlobalSpeciesWrite) {
			app.permissionDeniedResponse(w, r)
			return
		}
	} else if !member.Can(storage.GardenPermissionSpeciesWrite) {
		app.permissionDeniedResponse(w, r)
		return
	}
	var ownerGardenID *int
	if !input.Global {
		ownerGardenID = &gardenID
	}
	species := storage.Species{GardenID: ownerGardenID, Attributes: json.RawMessage(`{}`), CreatedBy: user.ID, UpdatedBy: user.ID}
	input.apply(&species)
	changedCategoryID := input.CategoryID
	if input.ClearCategoryID {
		changedCategoryID = nil
	}
	if !app.resolveSpeciesCategory(w, r, &species, changedCategoryID, nil) {
		return
	}
	species.Tags = storage.NormalizeTags(input.Tags)
	v := validate.New()
	validateImageData(v, species.ImageData)
	if storage.ValidateSpecies(v, species); !v.Valid() {
		app.failedValidationResponse(w, r, v.Errors)
		return
	}
	imageID, err := app.resolveImage(gardenID, species.ImageData, input.ImageID, user.ID, "species")
	if err != nil {
		app.badRequestResponse(w, r, err)
		return
	}
	species.ImageID = imageID
	species.ImageData = ""
	species, err = app.models.Species.Insert(species)
	if err != nil {
		app.respondToEntityModelError(w, r, err)
		return
	}
	if err = app.syncSeasonTaskTemplates(gardenID, species); err != nil {
		app.serverErrorResponse(w, r, err)
		return
	}
	tagScope := gardenID
	if species.GardenID == nil {
		tagScope = 0
	}
	species.Tags, err = app.saveTags(tagScope, storage.TagEntitySpecies, species.ID, species.Tags)
	if err != nil {
		app.serverErrorResponse(w, r, err)
		return
	}
	headers := make(http.Header)
	headers.Set("Location", fmt.Sprintf("/v1/gardens/%d/species/%d", gardenID, species.ID))
	if err := app.writeJSON(w, http.StatusCreated, envelope{"species": species}, headers); err != nil {
		app.serverErrorResponse(w, r, err)
	}
}

func (app *application) listSpeciesHandler(w http.ResponseWriter, r *http.Request) {
	gardenID, _ := app.readGardenIDParam(r)
	allSpecies, err := app.models.Species.GetAllForGarden(gardenID)
	if err != nil {
		app.serverErrorResponse(w, r, err)
		return
	}
	for i := range allSpecies {
		tagScope := gardenID
		if allSpecies[i].GardenID == nil {
			tagScope = 0
		}
		allSpecies[i].Tags, err = app.loadTags(tagScope, storage.TagEntitySpecies, allSpecies[i].ID)
		if err != nil {
			app.serverErrorResponse(w, r, err)
			return
		}
	}
	if err := app.writeJSON(w, http.StatusOK, envelope{"species": allSpecies}, nil); err != nil {
		app.serverErrorResponse(w, r, err)
	}
}

func (app *application) showSpeciesHandler(w http.ResponseWriter, r *http.Request) {
	gardenID, _ := app.readGardenIDParam(r)
	id, err := app.readIDParam(r)
	if err != nil {
		app.notFoundResponse(w, r)
		return
	}
	species, err := app.models.Species.Get(gardenID, id)
	if err != nil {
		app.respondToEntityModelError(w, r, err)
		return
	}
	tagScope := gardenID
	if species.GardenID == nil {
		tagScope = 0
	}
	species.Tags, err = app.loadTags(tagScope, storage.TagEntitySpecies, species.ID)
	if err != nil {
		app.serverErrorResponse(w, r, err)
		return
	}
	if err := app.writeJSON(w, http.StatusOK, envelope{"species": species}, nil); err != nil {
		app.serverErrorResponse(w, r, err)
	}
}

func (app *application) updateSpeciesHandler(w http.ResponseWriter, r *http.Request) {
	gardenID, _ := app.readGardenIDParam(r)
	id, err := app.readIDParam(r)
	if err != nil {
		app.notFoundResponse(w, r)
		return
	}
	species, err := app.models.Species.Get(gardenID, id)
	if err != nil {
		app.respondToEntityModelError(w, r, err)
		return
	}
	member, _ := app.contextGetGardenMember(r)
	user, _ := app.contextGetAuthenticatedUser(r)
	if species.GardenID == nil {
		if !user.Can(storage.ApplicationPermissionGlobalSpeciesWrite) {
			app.permissionDeniedResponse(w, r)
			return
		}
	} else if *species.GardenID != gardenID {
		app.notFoundResponse(w, r)
		return
	} else if !member.Can(storage.GardenPermissionSpeciesWrite) {
		app.permissionDeniedResponse(w, r)
		return
	}
	var input speciesInput
	if err := app.readJSON(w, r, &input); err != nil {
		app.badRequestResponse(w, r, err)
		return
	}
	previousCategoryID := species.CategoryID
	previousImageID := species.ImageID
	previousImageData := species.ImageData
	input.apply(&species)
	species.UpdatedBy = user.ID
	changedCategoryID := input.CategoryID
	if input.ClearCategoryID {
		changedCategoryID = nil
	}
	if !app.resolveSpeciesCategory(w, r, &species, changedCategoryID, previousCategoryID) {
		return
	}
	if input.Tags != nil {
		species.Tags = storage.NormalizeTags(input.Tags)
	}
	v := validate.New()
	validateImageData(v, species.ImageData)
	if storage.ValidateSpecies(v, species); !v.Valid() {
		app.failedValidationResponse(w, r, v.Errors)
		return
	}
	if input.ImageData != nil && *input.ImageData != previousImageData {
		species.ImageID, err = app.resolveImage(gardenID, *input.ImageData, input.ImageID, user.ID, "species")
		if err != nil {
			app.badRequestResponse(w, r, err)
			return
		}
	}
	species.ImageData = ""
	updateScope := gardenID
	if species.GardenID == nil {
		updateScope = 0
	}
	species, err = app.models.Species.Update(updateScope, species)
	if err != nil {
		app.respondToEntityModelError(w, r, err)
		return
	}
	if err = app.syncSeasonTaskTemplates(gardenID, species); err != nil {
		app.serverErrorResponse(w, r, err)
		return
	}
	if err = app.recordImageAssignment(storage.ImageAssignment{GardenID: gardenID, EntityType: "species", EntityID: species.ID, PreviousImageID: previousImageID, ImageID: species.ImageID, ChangedBy: user.ID}); err != nil {
		app.serverErrorResponse(w, r, err)
		return
	}
	if input.Tags != nil {
		species.Tags, err = app.saveTags(updateScope, storage.TagEntitySpecies, species.ID, species.Tags)
		if err != nil {
			app.serverErrorResponse(w, r, err)
			return
		}
	}
	if err := app.writeJSON(w, http.StatusOK, envelope{"species": species}, nil); err != nil {
		app.serverErrorResponse(w, r, err)
	}
}

func (app *application) resolveSpeciesCategory(w http.ResponseWriter, r *http.Request, species *storage.Species, changedID, existingID *int) bool {
	if changedID == nil {
		return true
	}
	category, err := app.models.SpeciesCategories.Get(*changedID)
	keepsInactiveCategory := existingID != nil && *existingID == *changedID
	if err != nil || !category.Active && !keepsInactiveCategory {
		app.failedValidationResponse(w, r, map[string]string{"category_id": "must reference an active category"})
		return false
	}
	species.Category = category.Name
	return true
}

func (app *application) deleteSpeciesHandler(w http.ResponseWriter, r *http.Request) {
	gardenID, _ := app.readGardenIDParam(r)
	id, err := app.readIDParam(r)
	if err != nil {
		app.notFoundResponse(w, r)
		return
	}
	species, writable := app.requireWritableSpecies(w, r, gardenID, id)
	if !writable {
		return
	}
	deleteScope := gardenID
	if species.GardenID == nil {
		deleteScope = 0
	}
	if err := app.models.Species.Delete(deleteScope, id); err != nil {
		app.respondToEntityModelError(w, r, err)
		return
	}
	w.WriteHeader(http.StatusNoContent)
}

func (app *application) respondToEntityModelError(w http.ResponseWriter, r *http.Request, err error) {
	switch {
	case errors.Is(err, storage.ErrRecordNotFound):
		app.notFoundResponse(w, r)
	case errors.Is(err, storage.ErrEditConflict):
		app.editConflictResponse(w, r)
	case errors.Is(err, storage.ErrConflict):
		app.conflictResponse(w, r)
	default:
		app.serverErrorResponse(w, r, err)
	}
}