package handlers

import (
	"fmt"
	"net/http"

	"github.com/breakpilot/ai-compliance-sdk/internal/iace"
	"github.com/gin-gonic/gin"
	"github.com/google/uuid"
)

// InitStep tracks progress of each initialization step.
type InitStep struct {
	Name    string `json:"name"`
	Status  string `json:"status"` // "done", "skipped", "error"
	Count   int    `json:"count,omitempty"`
	Details string `json:"details,omitempty"`
}

// InitializeProject handles POST /projects/:id/initialize
// Chains: parse narrative → create components → fire patterns →
// create hazards + measures + verification → suggest norms.
// Idempotent: skips steps that are already populated.
func (h *IACEHandler) InitializeProject(c *gin.Context) {
	projectID, err := uuid.Parse(c.Param("id"))
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid project ID"})
		return
	}

	tenantID, err := getTenantID(c)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	ctx := c.Request.Context()
	project, err := h.store.GetProject(ctx, projectID)
	if err != nil || project == nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "project not found"})
		return
	}

	// Support ?force=true to clear existing hazards + mitigations before re-init
	forceReinit := c.Query("force") == "true"

	steps := make([]InitStep, 0, 6)

	// ── Step 0 (optional): Clear existing data for force re-init ──
	if forceReinit {
		cleared := 0
		if mits, _ := h.store.ListMitigationsByProject(ctx, projectID); len(mits) > 0 {
			for _, m := range mits {
				_ = h.store.DeleteMitigation(ctx, m.ID)
				cleared++
			}
		}
		if hazards, _ := h.store.ListHazards(ctx, projectID); len(hazards) > 0 {
			for _, hz := range hazards {
				_ = h.store.DeleteHazard(ctx, hz.ID)
				cleared++
			}
		}
		steps = append(steps, InitStep{Name: "Alte Daten geloescht", Status: "done", Count: cleared})
	}

	// ── Step 1: Extract narrative from limits_form ──
	narrativeText := extractNarrativeFromMetadata(project.Metadata)
	if narrativeText == "" {
		c.JSON(http.StatusBadRequest, gin.H{
			"error": "Grenzen-Formular ist leer. Bitte zuerst die Maschinenbeschreibung ausfuellen.",
		})
		return
	}

	// ── Step 2: Parse narrative deterministically ──
	parseResult := iace.ParseNarrative(narrativeText, project.MachineType)
	steps = append(steps, InitStep{
		Name:    "Narrative analysiert",
		Status:  "done",
		Count:   len(parseResult.Components),
		Details: fmt.Sprintf("%d Komponenten, %d Energiequellen, %d Tags", len(parseResult.Components), len(parseResult.EnergySources), len(parseResult.CustomTags)),
	})

	// ── Step 3: Create components (skip if already exist) ──
	existingComps, _ := h.store.ListComponents(ctx, projectID)
	compStep := InitStep{Name: "Komponenten erstellt", Status: "skipped"}
	if len(existingComps) == 0 && len(parseResult.Components) > 0 {
		created := 0
		for _, comp := range parseResult.Components {
			compType := deriveComponentType(comp.Tags)
			_, cerr := h.store.CreateComponent(ctx, iace.CreateComponentRequest{
				ProjectID:     projectID,
				Name:          comp.NameDE,
				ComponentType: compType,
				Description:   "Auto-erkannt aus Maschinenbeschreibung (" + comp.MatchedOn + ")",
			})
			if cerr == nil {
				created++
			}
		}
		compStep = InitStep{Name: "Komponenten erstellt", Status: "done", Count: created}
	} else if len(existingComps) > 0 {
		compStep.Details = "Bereits vorhanden"
		compStep.Count = len(existingComps)
	}
	steps = append(steps, compStep)

	// ── Step 4: Fire pattern engine ──
	var componentIDs, energyIDs []string
	for _, comp := range parseResult.Components {
		componentIDs = append(componentIDs, comp.LibraryID)
	}
	for _, e := range parseResult.EnergySources {
		energyIDs = append(energyIDs, e.SourceID)
	}

	operationalStates := mergeStringSlices(parseResult.OperationalStates, extractOperationalStatesFromMetadata(project.Metadata))
	machineTypes := extractIndustrySectorsFromMetadata(project.Metadata)

	engine := iace.NewPatternEngine()
	matchOutput := engine.Match(iace.MatchInput{
		ComponentLibraryIDs: componentIDs,
		EnergySourceIDs:     energyIDs,
		LifecyclePhases:     parseResult.LifecyclePhases,
		CustomTags:          parseResult.CustomTags,
		OperationalStates:   operationalStates,
		StateTransitions:    parseResult.StateTransitions,
		HumanRoles:          parseResult.Roles,
		MachineTypes:        machineTypes,
	})
	steps = append(steps, InitStep{
		Name:   "Patterns abgeglichen",
		Status: "done",
		Count:  len(matchOutput.MatchedPatterns),
	})

	// ── Step 5: Create hazards from matched patterns (skip if exist) ──
	existingHazards, _ := h.store.ListHazards(ctx, projectID)
	hazardStep := InitStep{Name: "Gefaehrdungen erstellt", Status: "skipped"}
	hazardIDsByCategory := make(map[string]uuid.UUID)

	if len(existingHazards) == 0 && len(matchOutput.MatchedPatterns) > 0 {
		comps, _ := h.store.ListComponents(ctx, projectID)
		var defaultCompID uuid.UUID
		if len(comps) > 0 {
			defaultCompID = comps[0].ID
		}

		created := 0
		seenCat := make(map[string]bool)
		for _, mp := range matchOutput.MatchedPatterns {
			for _, cat := range mp.HazardCats {
				if seenCat[cat] {
					continue
				}
				seenCat[cat] = true

				name := mp.PatternName
				if name == "" {
					name = cat
				}
				hz, cerr := h.store.CreateHazard(ctx, iace.CreateHazardRequest{
					ProjectID:      projectID,
					ComponentID:    defaultCompID,
					Name:           name,
					Description:    mp.ScenarioDE,
					Category:       cat,
					Scenario:       mp.ScenarioDE,
					Function:       iace.EncodeOpStates(mp.OperationalStates),
					TriggerEvent:   mp.TriggerDE,
					PossibleHarm:   mp.HarmDE,
					AffectedPerson: mp.AffectedDE,
					HazardousZone:  mp.ZoneDE,
				})
				if cerr == nil {
					created++
					hazardIDsByCategory[cat] = hz.ID
				}
			}
		}
		hazardStep = InitStep{Name: "Gefaehrdungen erstellt", Status: "done", Count: created}
	} else if len(existingHazards) > 0 {
		hazardStep.Details = "Bereits vorhanden"
		hazardStep.Count = len(existingHazards)
		for _, eh := range existingHazards {
			hazardIDsByCategory[eh.Category] = eh.ID
		}
	}
	steps = append(steps, hazardStep)

	// ── Step 6: Create mitigations ──
	existingMits, _ := h.store.ListMitigationsByProject(ctx, projectID)
	mitStep := InitStep{Name: "Massnahmen erstellt", Status: "skipped"}

	if len(existingMits) == 0 && len(hazardIDsByCategory) > 0 {
		measureLib := iace.GetProtectiveMeasureLibrary()
		measureByID := make(map[string]iace.ProtectiveMeasureEntry, len(measureLib))
		measuresByCat := make(map[string][]iace.ProtectiveMeasureEntry)
		for _, m := range measureLib {
			measureByID[m.ID] = m
			measuresByCat[m.HazardCategory] = append(measuresByCat[m.HazardCategory], m)
		}

		created := 0
		usedMeasureIDs := make(map[string]bool)

		for _, sm := range matchOutput.SuggestedMeasures {
			entry, ok := measureByID[sm.MeasureID]
			if !ok || usedMeasureIDs[sm.MeasureID] {
				continue
			}
			hazardID := findHazardForMeasureByCategory(entry.HazardCategory, hazardIDsByCategory)
			if hazardID == uuid.Nil {
				continue
			}
			rt := iace.ReductionType(entry.ReductionType)
			if rt == "" {
				rt = iace.ReductionTypeInformation
			}
			_, cerr := h.store.CreateMitigation(ctx, iace.CreateMitigationRequest{
				HazardID: hazardID, ReductionType: rt,
				Name: entry.Name, Description: entry.Description,
			})
			if cerr == nil {
				created++
				usedMeasureIDs[sm.MeasureID] = true
			}
		}

		for hazCat, hazID := range hazardIDsByCategory {
			measCat := patternCatToMeasureCat(hazCat)
			added := 0
			for _, m := range measuresByCat[measCat] {
				if usedMeasureIDs[m.ID] || added >= 8 {
					break
				}
				rt := iace.ReductionType(m.ReductionType)
				if rt == "" {
					rt = iace.ReductionTypeInformation
				}
				_, cerr := h.store.CreateMitigation(ctx, iace.CreateMitigationRequest{
					HazardID: hazID, ReductionType: rt,
					Name: m.Name, Description: m.Description,
				})
				if cerr == nil {
					created++
					usedMeasureIDs[m.ID] = true
					added++
				}
			}
		}
		mitStep = InitStep{Name: "Massnahmen erstellt", Status: "done", Count: created}
	} else if len(existingMits) > 0 {
		mitStep.Details = "Bereits vorhanden"
		mitStep.Count = len(existingMits)
	}
	steps = append(steps, mitStep)

	// ── Step 7: Suggest norms ──
	var hazardCats []string
	for cat := range hazardIDsByCategory {
		hazardCats = append(hazardCats, cat)
	}
	normResult := iace.SuggestNorms(project.MachineType, hazardCats, parseResult.CustomTags)
	normCount := 0
	if normResult != nil {
		normCount = len(normResult.ANorms) + len(normResult.B1Norms) + len(normResult.B2Norms) + len(normResult.CNorms)
	}
	steps = append(steps, InitStep{Name: "Normen vorgeschlagen", Status: "done", Count: normCount})

	// ── Audit trail ──
	h.store.AddAuditEntry(ctx, projectID, "project_initialization", projectID,
		iace.AuditActionCreate, tenantID.String(), nil,
		mustMarshalJSON(map[string]interface{}{"steps": steps}),
	)

	c.JSON(http.StatusOK, gin.H{
		"project_id": projectID.String(),
		"steps":      steps,
		"summary": gin.H{
			"components": steps[1].Count, "patterns": steps[2].Count,
			"hazards": steps[3].Count, "mitigations": steps[4].Count,
			"norms": steps[5].Count,
		},
	})
}