package handlers

import (
	"net/http"

	"github.com/flatrender/render-svc/internal/db"
	"github.com/flatrender/render-svc/internal/models"
	"github.com/flatrender/render-svc/internal/notifier"
	"github.com/gin-gonic/gin"
	"github.com/google/uuid"
)

type InternalHandler struct {
	store    *db.Store
	notifier *notifier.Client // may be nil — notifications are best-effort
}

func NewInternalHandler(store *db.Store, n *notifier.Client) *InternalHandler {
	return &InternalHandler{store: store, notifier: n}
}

// completeRequest is the body for POST .../complete
type completeRequest struct {
	ExportID *uuid.UUID `json:"export_id"`
}

// failRequest is the body for POST .../fail
type failRequest struct {
	Reason string `json:"reason" binding:"required"`
	AtStep string `json:"at_step"` // optional: which render step failed
}

// POST /v1/internal/render/jobs/:job_id/complete
func (h *InternalHandler) Complete(c *gin.Context) {
	jobID, err := uuid.Parse(c.Param("job_id"))
	if err != nil {
		c.JSON(http.StatusBadRequest, models.APIError{Code: "bad_request", Message: "invalid job_id"})
		return
	}
	var req completeRequest
	_ = c.ShouldBindJSON(&req) // export_id is optional

	job, err := h.store.CompleteJob(c.Request.Context(), jobID, req.ExportID)
	if err != nil {
		c.JSON(http.StatusInternalServerError, models.APIError{Code: "internal_error", Message: err.Error()})
		return
	}

	// Fire notification if the user requested it (tell_me_when_done)
	if h.notifier != nil && job.TellMeWhenDone {
		jobName := ""
		if job.Name != nil {
			jobName = *job.Name
		} else if job.Title != nil {
			jobName = *job.Title
		}
		h.notifier.NotifyRenderDone(c.Request.Context(),
			job.UserID, job.TenantID, job.ID, job.ExportID, jobName)
	}

	c.JSON(http.StatusOK, gin.H{"status": "done", "job_id": job.ID})
}

// POST /v1/internal/render/jobs/:job_id/fail
func (h *InternalHandler) Fail(c *gin.Context) {
	jobID, err := uuid.Parse(c.Param("job_id"))
	if err != nil {
		c.JSON(http.StatusBadRequest, models.APIError{Code: "bad_request", Message: "invalid job_id"})
		return
	}
	var req failRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, models.APIError{Code: "bad_request", Message: err.Error()})
		return
	}
	atStep := req.AtStep
	if atStep == "" {
		atStep = "Rendering"
	}

	job, err := h.store.FailJob(c.Request.Context(), jobID, req.Reason, atStep)
	if err != nil {
		c.JSON(http.StatusInternalServerError, models.APIError{Code: "internal_error", Message: err.Error()})
		return
	}

	// Notify user of failure
	if h.notifier != nil {
		jobName := ""
		if job.Name != nil {
			jobName = *job.Name
		} else if job.Title != nil {
			jobName = *job.Title
		}
		h.notifier.NotifyRenderFailed(c.Request.Context(),
			job.UserID, job.TenantID, job.ID, jobName, req.Reason)
	}

	c.JSON(http.StatusOK, gin.H{"status": "failed", "job_id": job.ID})
}

// POST /v1/internal/nodes/:node_id/heartbeat
func (h *InternalHandler) Heartbeat(c *gin.Context) {
	nodeID, err := uuid.Parse(c.Param("node_id"))
	if err != nil {
		c.JSON(http.StatusBadRequest, models.APIError{Code: "bad_request", Message: "invalid node_id"})
		return
	}
	var req models.NodeHeartbeatRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, models.APIError{Code: "bad_request", Message: err.Error()})
		return
	}
	req.NodeID = nodeID
	if err := h.store.UpdateNodeHeartbeat(c.Request.Context(), nodeID, &req); err != nil {
		c.JSON(http.StatusInternalServerError, models.APIError{Code: "internal_error", Message: err.Error()})
		return
	}
	c.JSON(http.StatusOK, gin.H{
		"next_heartbeat_in_sec": 5,
		"pending_commands":      []any{},
	})
}

// POST /v1/internal/nodes/:node_id/online
func (h *InternalHandler) Online(c *gin.Context) {
	nodeID, err := uuid.Parse(c.Param("node_id"))
	if err != nil {
		c.JSON(http.StatusBadRequest, models.APIError{Code: "bad_request", Message: "invalid node_id"})
		return
	}
	var req models.NodeOnlineRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, models.APIError{Code: "bad_request", Message: err.Error()})
		return
	}
	if err := h.store.UpdateNodeOnline(c.Request.Context(), nodeID, &req); err != nil {
		c.JSON(http.StatusInternalServerError, models.APIError{Code: "internal_error", Message: err.Error()})
		return
	}
	c.Status(http.StatusOK)
}

// POST /v1/internal/render/jobs/:job_id/frames
func (h *InternalHandler) FrameProgress(c *gin.Context) {
	jobID, err := uuid.Parse(c.Param("job_id"))
	if err != nil {
		c.JSON(http.StatusBadRequest, models.APIError{Code: "bad_request", Message: "invalid job_id"})
		return
	}
	var req models.FrameProgressRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, models.APIError{Code: "bad_request", Message: err.Error()})
		return
	}
	if err := h.store.UpdateFrameProgress(c.Request.Context(), jobID, &req); err != nil {
		c.JSON(http.StatusInternalServerError, models.APIError{Code: "internal_error", Message: err.Error()})
		return
	}
	c.Status(http.StatusNoContent)
}

// POST /v1/internal/render/jobs/:job_id/crash
func (h *InternalHandler) Crash(c *gin.Context) {
	jobID, err := uuid.Parse(c.Param("job_id"))
	if err != nil {
		c.JSON(http.StatusBadRequest, models.APIError{Code: "bad_request", Message: "invalid job_id"})
		return
	}
	var req models.CrashReportRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, models.APIError{Code: "bad_request", Message: err.Error()})
		return
	}
	if err := h.store.InsertCrash(c.Request.Context(), req.NodeID, jobID, &req); err != nil {
		c.JSON(http.StatusInternalServerError, models.APIError{Code: "internal_error", Message: err.Error()})
		return
	}
	c.JSON(http.StatusOK, gin.H{
		"action_recommended":     "ResetAndRestart",
		"reassigned_to_node_id": nil,
	})
}

// POST /v1/internal/render/jobs/:job_id/replica-ready
func (h *InternalHandler) ReplicaReady(c *gin.Context) {
	_, err := uuid.Parse(c.Param("job_id"))
	if err != nil {
		c.JSON(http.StatusBadRequest, models.APIError{Code: "bad_request", Message: "invalid job_id"})
		return
	}
	var req models.ReplicaReadyRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, models.APIError{Code: "bad_request", Message: err.Error()})
		return
	}
	// In production: update job step to TemplateCache → JsxGen, signal next pipeline phase
	c.Status(http.StatusNoContent)
}

// POST /v1/internal/nodes/:node_id/cache-update
func (h *InternalHandler) CacheUpdate(c *gin.Context) {
	nodeID, err := uuid.Parse(c.Param("node_id"))
	if err != nil {
		c.JSON(http.StatusBadRequest, models.APIError{Code: "bad_request", Message: "invalid node_id"})
		return
	}
	var req models.CacheUpdateRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, models.APIError{Code: "bad_request", Message: err.Error()})
		return
	}
	if err := h.store.UpdateNodeCache(c.Request.Context(), nodeID, &req); err != nil {
		c.JSON(http.StatusInternalServerError, models.APIError{Code: "internal_error", Message: err.Error()})
		return
	}
	c.Status(http.StatusNoContent)
}