package analize

import (
	"errors"
	"fmt"
	"math"
	"net/http"
	"strconv"
	"strings"

	"control/control_case"
	"github.com/che4web/go4rest"
	"github.com/gin-gonic/gin"
	"gorm.io/gorm"
)

type AnalizeController struct {
	*go4rest.ViewSet[Analize]
	db *gorm.DB
}

func NewAnalizeController(db *gorm.DB) *AnalizeController {
	return &AnalizeController{
		ViewSet: go4rest.NewViewSet[Analize](db),
		db:      db,
	}
}

type AnalizeSeriesPoint struct {
	CaseID   uint    `json:"case_id"`
	CaseName string  `json:"case_name"`
	X        float64 `json:"x"`
	Omega    float64 `json:"omega"`
	PsiMax   float64 `json:"psi_max"`
}

type AnalizeSeriesGroup struct {
	GroupValue float64              `json:"group_value"`
	GroupLabel string               `json:"group_label"`
	Points     []AnalizeSeriesPoint `json:"points"`
}

type AnalizeSeriesResponse struct {
	Parameter      string               `json:"parameter"`
	Label          string               `json:"label"`
	GroupParameter string               `json:"group_parameter,omitempty"`
	GroupLabel     string               `json:"group_label,omitempty"`
	Points         []AnalizeSeriesPoint `json:"points,omitempty"`
	Groups         []AnalizeSeriesGroup `json:"groups,omitempty"`
}

var analizeParameterColumns = map[string]struct {
	Column string
	Label  string
}{
	"Rel":  {Column: "rel", Label: "Rel"},
	"RelC": {Column: "rel_c", Label: "RelC"},
	"Le":   {Column: "le", Label: "Le"},
	"Pr":   {Column: "sc", Label: "Sc"},
	"Sc":   {Column: "sc", Label: "Sc"},
	"Pe":   {Column: "pe", Label: "Pe"},
	"Ma":   {Column: "ma", Label: "Ma"},
	"Time": {Column: "time", Label: "Time"},
}

func (c *AnalizeController) Series(ctx *gin.Context) {
	param := ctx.DefaultQuery("parameter", "Rel")
	selected, ok := analizeParameterColumns[param]
	if !ok {
		ctx.JSON(http.StatusBadRequest, gin.H{"error": "invalid parameter"})
		return
	}

	groupParam := ctx.Query("group_parameter")
	groupSelected, groupOK := analizeParameterColumns[groupParam]
	if groupParam != "" && !groupOK {
		ctx.JSON(http.StatusBadRequest, gin.H{"error": "invalid group parameter"})
		return
	}

	filterParam := ctx.Query("filter_parameter")
	filterSelected, filterOK := analizeParameterColumns[filterParam]
	filterMin := ctx.Query("filter_min")
	filterMax := ctx.Query("filter_max")

	type row struct {
		CaseID   uint    `gorm:"column:case_id"`
		CaseName string  `gorm:"column:case_name"`
		GroupVal float64 `gorm:"column:group_val"`
		X        float64 `gorm:"column:x"`
		Omega    float64 `gorm:"column:omega"`
		PsiMax   float64 `gorm:"column:psi_max"`
	}

	groupExpr := groupExpr(groupParam, groupSelected.Column)
	query := fmt.Sprintf(`
		SELECT a.case_id, a.case_name, %s AS group_val, p.%s AS x, a.omega, a.psi_max
		FROM analizes a
		JOIN control_cases c ON c.id = a.case_id
		JOIN params p ON p.id = c.params_id
	`, groupExpr, selected.Column)
	where := make([]string, 0, 2)
	args := make([]any, 0, 2)
	if filterParam != "" {
		if !filterOK {
			ctx.JSON(http.StatusBadRequest, gin.H{"error": "invalid filter parameter"})
			return
		}
		if filterMin != "" {
			where = append(where, fmt.Sprintf("p.%s >= ?", filterSelected.Column))
			args = append(args, filterMin)
		}
		if filterMax != "" {
			where = append(where, fmt.Sprintf("p.%s <= ?", filterSelected.Column))
			args = append(args, filterMax)
		}
	}
	if len(where) > 0 {
		query += " WHERE " + strings.Join(where, " AND ")
	}
	if groupParam != "" {
		query += fmt.Sprintf(" ORDER BY ROUND(p.%s, 6), p.%s, a.id", groupSelected.Column, selected.Column)
	} else {
		query += fmt.Sprintf(" ORDER BY p.%s, a.id", selected.Column)
	}

	var rows []row
	if err := c.db.Raw(query, args...).Scan(&rows).Error; err != nil {
		ctx.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	points := make([]AnalizeSeriesPoint, 0, len(rows))
	groups := make([]AnalizeSeriesGroup, 0)
	if groupParam == "" {
		for _, r := range rows {
			points = append(points, AnalizeSeriesPoint{
				CaseID:   r.CaseID,
				CaseName: r.CaseName,
				X:        r.X,
				Omega:    r.Omega,
				PsiMax:   r.PsiMax,
			})
		}
	} else {
		groupIndex := map[string]int{}
		for _, r := range rows {
			groupValue := round6(r.GroupVal)
			key := fmt.Sprintf("%.6f", groupValue)
			idx, ok := groupIndex[key]
			if !ok {
				idx = len(groups)
				groupIndex[key] = idx
				groups = append(groups, AnalizeSeriesGroup{
					GroupValue: groupValue,
					GroupLabel: fmt.Sprintf("%s=%.6f", groupSelected.Label, groupValue),
					Points:     []AnalizeSeriesPoint{},
				})
			}
			groups[idx].Points = append(groups[idx].Points, AnalizeSeriesPoint{
				CaseID:   r.CaseID,
				CaseName: r.CaseName,
				X:        r.X,
				Omega:    r.Omega,
				PsiMax:   r.PsiMax,
			})
		}
	}

	ctx.JSON(http.StatusOK, AnalizeSeriesResponse{
		Parameter:      param,
		Label:          selected.Label,
		GroupParameter: groupParam,
		GroupLabel:     groupSelected.Label,
		Points:         points,
		Groups:         groups,
	})
}

func groupExpr(groupParam, groupColumn string) string {
	if groupParam == "" {
		return "0"
	}
	return fmt.Sprintf("ROUND(p.%s, 6)", groupColumn)
}

func round6(v float64) float64 {
	return math.Round(v*1e6) / 1e6
}

func (c *AnalizeController) Recalculate(ctx *gin.Context) {
	id, err := strconv.ParseUint(ctx.Param("id"), 10, 32)
	if err != nil {
		ctx.JSON(http.StatusBadRequest, gin.H{"error": "invalid ID"})
		return
	}

	var item Analize
	if err := c.db.First(&item, id).Error; err != nil {
		ctx.JSON(http.StatusNotFound, gin.H{"error": "record not found"})
		return
	}

	var controlCase control_case.ControlCase
	if err := c.db.First(&controlCase, item.CaseID).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			ctx.JSON(http.StatusNotFound, gin.H{"error": "control case not found"})
		} else {
			ctx.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		}
		return
	}

	csvPath := controlCase.FooCSVPath()
	updated, err := AnalyzeCSV(c.db, item.CaseID, item.CaseName, csvPath)
	if err != nil {
		ctx.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	ctx.JSON(http.StatusOK, updated)
}

func (c *AnalizeController) RecalculateControlCaseAnalysis(ctx *gin.Context) {
	id, err := strconv.ParseUint(ctx.Param("id"), 10, 32)
	if err != nil {
		ctx.JSON(http.StatusBadRequest, gin.H{"error": "invalid ID"})
		return
	}

	var controlCase control_case.ControlCase
	if err := c.db.First(&controlCase, id).Error; err != nil {
		ctx.JSON(http.StatusNotFound, gin.H{"error": "record not found"})
		return
	}

	result, err := AnalyzeCSV(c.db, controlCase.ID, controlCase.Name, controlCase.FooCSVPath())
	if err != nil {
		ctx.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	ctx.JSON(http.StatusOK, result)
}