package handlers

import (
	"net/http"
	"os"

	"github.com/gin-gonic/gin"
	"sproutclaw-web/internal/config"
	"sproutclaw-web/internal/db"
	"sproutclaw-web/internal/models"
	"sproutclaw-web/internal/rpc"
	"sproutclaw-web/internal/services"
	"sproutclaw-web/internal/utils"
)

// RegisterSessions registers all session management routes.
func RegisterSessions(r *gin.RouterGroup, cfg *config.Config, database *db.DB, piClient *rpc.Client) {
	r.GET("/sessions", handleListSessions(cfg, database))
	r.POST("/new-session", handleNewSession(piClient))
	r.POST("/sessions/history", handleSessionHistory(cfg))
	r.POST("/sessions/delete", handleDeleteSession(cfg, database))
	r.POST("/sessions/pin", handlePinSession(cfg, database))
	r.POST("/sessions/load", handleLoadSession(cfg, piClient))
	r.POST("/sessions/activate", handleActivateSession(cfg, piClient))
	r.POST("/sessions/name", handleNameSession(cfg))
	r.GET("/session-state", handleSessionState(piClient))
}

func handleListSessions(cfg *config.Config, database *db.DB) gin.HandlerFunc {
	return func(c *gin.Context) {
		summaries, err := services.BuildSessionList(cfg.SessionsDir, database)
		if err != nil {
			c.JSON(http.StatusInternalServerError, models.ErrorResponse{Error: err.Error()})
			return
		}
		if summaries == nil {
			summaries = []models.SessionSummary{}
		}
		c.JSON(http.StatusOK, models.SessionsResponse{Sessions: summaries})
	}
}

func handleNewSession(piClient *rpc.Client) gin.HandlerFunc {
	return func(c *gin.Context) {
		resp, err := piClient.SendCmd(models.RPCCommand{Type: "new_session"})
		if err != nil {
			c.JSON(http.StatusInternalServerError, models.ErrorResponse{Error: err.Error()})
			return
		}
		c.JSON(http.StatusOK, jsonRaw(resp.Result))
	}
}

func handleSessionHistory(cfg *config.Config) gin.HandlerFunc {
	return func(c *gin.Context) {
		var req models.HistoryRequest
		if err := c.ShouldBindJSON(&req); err != nil {
			c.JSON(http.StatusBadRequest, models.ErrorResponse{Error: err.Error()})
			return
		}
		if !utils.IsPathInsideRoot(cfg.SessionsDir, req.Path) {
			c.JSON(http.StatusForbidden, models.ErrorResponse{Error: "invalid path"})
			return
		}
		lines, err := services.ReadSessionMessages(req.Path)
		if err != nil {
			c.JSON(http.StatusNotFound, models.ErrorResponse{Error: err.Error()})
			return
		}
		c.JSON(http.StatusOK, gin.H{"messages": lines})
	}
}

func handleDeleteSession(cfg *config.Config, database *db.DB) gin.HandlerFunc {
	return func(c *gin.Context) {
		var req models.DeleteSessionRequest
		if err := c.ShouldBindJSON(&req); err != nil {
			c.JSON(http.StatusBadRequest, models.ErrorResponse{Error: err.Error()})
			return
		}
		if !utils.IsPathInsideRoot(cfg.SessionsDir, req.Path) {
			c.JSON(http.StatusForbidden, models.ErrorResponse{Error: "invalid path"})
			return
		}
		if err := os.Remove(req.Path); err != nil && !os.IsNotExist(err) {
			c.JSON(http.StatusInternalServerError, models.ErrorResponse{Error: err.Error()})
			return
		}
		_ = database.SetSessionPinned(req.Path, false)
		c.JSON(http.StatusOK, models.OKResponse{OK: true})
	}
}

func handlePinSession(cfg *config.Config, database *db.DB) gin.HandlerFunc {
	return func(c *gin.Context) {
		var req models.PinSessionRequest
		if err := c.ShouldBindJSON(&req); err != nil {
			c.JSON(http.StatusBadRequest, models.ErrorResponse{Error: err.Error()})
			return
		}
		if !utils.IsPathInsideRoot(cfg.SessionsDir, req.Path) {
			c.JSON(http.StatusForbidden, models.ErrorResponse{Error: "invalid path"})
			return
		}
		if err := database.SetSessionPinned(req.Path, req.Pinned); err != nil {
			c.JSON(http.StatusInternalServerError, models.ErrorResponse{Error: err.Error()})
			return
		}
		c.JSON(http.StatusOK, models.OKResponse{OK: true})
	}
}

func handleLoadSession(cfg *config.Config, piClient *rpc.Client) gin.HandlerFunc {
	return func(c *gin.Context) {
		var req models.LoadSessionRequest
		if err := c.ShouldBindJSON(&req); err != nil {
			c.JSON(http.StatusBadRequest, models.ErrorResponse{Error: err.Error()})
			return
		}
		if !utils.IsPathInsideRoot(cfg.SessionsDir, req.Path) {
			c.JSON(http.StatusForbidden, models.ErrorResponse{Error: "invalid path"})
			return
		}
		lines, err := services.ReadSessionMessages(req.Path)
		if err != nil {
			c.JSON(http.StatusNotFound, models.ErrorResponse{Error: err.Error()})
			return
		}
		resp, err := piClient.SendCmd(models.RPCCommand{
			Type: "switch_session",
			Path: req.Path,
		})
		if err != nil {
			c.JSON(http.StatusInternalServerError, models.ErrorResponse{Error: err.Error()})
			return
		}
		c.JSON(http.StatusOK, gin.H{"messages": lines, "result": jsonRaw(resp.Result)})
	}
}

func handleActivateSession(cfg *config.Config, piClient *rpc.Client) gin.HandlerFunc {
	return func(c *gin.Context) {
		var req models.ActivateSessionRequest
		if err := c.ShouldBindJSON(&req); err != nil {
			c.JSON(http.StatusBadRequest, models.ErrorResponse{Error: err.Error()})
			return
		}
		if !utils.IsPathInsideRoot(cfg.SessionsDir, req.Path) {
			c.JSON(http.StatusForbidden, models.ErrorResponse{Error: "invalid path"})
			return
		}
		resp, err := piClient.SendCmd(models.RPCCommand{
			Type: "switch_session",
			Path: req.Path,
		})
		if err != nil {
			c.JSON(http.StatusInternalServerError, models.ErrorResponse{Error: err.Error()})
			return
		}
		c.JSON(http.StatusOK, jsonRaw(resp.Result))
	}
}

func handleNameSession(cfg *config.Config) gin.HandlerFunc {
	return func(c *gin.Context) {
		var req models.NameSessionRequest
		if err := c.ShouldBindJSON(&req); err != nil {
			c.JSON(http.StatusBadRequest, models.ErrorResponse{Error: err.Error()})
			return
		}
		if !utils.IsPathInsideRoot(cfg.SessionsDir, req.Path) {
			c.JSON(http.StatusForbidden, models.ErrorResponse{Error: "invalid path"})
			return
		}
		if err := services.AppendSessionName(req.Path, req.Name); err != nil {
			c.JSON(http.StatusInternalServerError, models.ErrorResponse{Error: err.Error()})
			return
		}
		c.JSON(http.StatusOK, models.OKResponse{OK: true})
	}
}

func handleSessionState(piClient *rpc.Client) gin.HandlerFunc {
	return func(c *gin.Context) {
		snap := piClient.GetSnapshot()
		c.JSON(http.StatusOK, models.SessionStateResponse{
			IsStreaming: snap.IsStreaming,
			SessionFile: snap.SessionFile,
		})
	}
}