/*
Copyright 2025-2026 linux.do
Modified by Arctel.net, 2026

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package task

import (
	"fmt"
	"net/http"
	"strconv"
	"strings"
	"time"

	"github.com/Rain-kl/Wavelet/internal/apps/admin"
	"github.com/Rain-kl/Wavelet/internal/model"
	"github.com/Rain-kl/Wavelet/internal/task"
	taskhandlers "github.com/Rain-kl/Wavelet/internal/task/handlers"
	"github.com/Rain-kl/Wavelet/internal/util"
	"github.com/gin-gonic/gin"
)

func init() {
	taskhandlers.Register()
}

// ListTaskTypes 获取支持的任务类型列表
// @Summary 获取支持的任务类型
// @Description 返回系统支持的所有可调度任务类型列表，包括任务名称、描述、是否支持时间范围等元数据，需要管理员权限
// @Tags admin
// @Produce json
// @Security SessionCookie
// @Success 200 {object} util.ResponseAny{data=[]task.TaskMeta} "任务类型列表"
// @Failure 401 {object} util.ResponseAny "未登录"
// @Failure 403 {object} util.ResponseAny "无管理员权限"
// @Router /api/v1/admin/tasks/types [get]
func ListTaskTypes(c *gin.Context) {
	c.JSON(http.StatusOK, util.OK(task.DispatchableTasks))
}

// DispatchTaskRequest 下发任务请求
type DispatchTaskRequest struct {
	TaskType  string     `json:"task_type" binding:"required"`
	StartTime *time.Time `json:"start_time"`
	EndTime   *time.Time `json:"end_time"`
	UserID    *uint64    `json:"user_id"`
	Payload   string     `json:"payload"`
}

// DispatchTask 下发任务
// @Summary 下发异步任务
// @Description 手动触发指定类型的异步任务，支持指定时间范围和用户，需要管理员权限
// @Tags admin
// @Accept json
// @Produce json
// @Security SessionCookie
// @Param request body DispatchTaskRequest true "任务请求参数"
// @Success 200 {object} util.ResponseAny{data=string} "任务已入队"
// @Failure 400 {object} util.ResponseAny "任务类型不存在或参数错误"
// @Failure 401 {object} util.ResponseAny "未登录"
// @Failure 403 {object} util.ResponseAny "无管理员权限"
// @Failure 500 {object} util.ResponseAny "任务入队失败"
// @Router /api/v1/admin/tasks/dispatch [post]
func DispatchTask(c *gin.Context) {
	var req DispatchTaskRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, util.Err(err.Error()))
		return
	}

	meta := task.GetTaskMeta(req.TaskType)
	if meta == nil {
		c.JSON(http.StatusBadRequest, util.Err(InvalidTaskType))
		return
	}

	var payloadBytes []byte
	if strings.TrimSpace(req.Payload) != "" {
		payloadBytes = []byte(req.Payload)
	}

	validated, err := task.ValidateAndNormalizePayload(meta.AsynqTask, payloadBytes)
	if err != nil {
		c.JSON(http.StatusBadRequest, util.Err(err.Error()))
		return
	}

	taskID, err := task.DispatchTask(c.Request.Context(), req.TaskType, validated, "manual")
	if err != nil {
		c.JSON(http.StatusInternalServerError, util.Err(fmt.Sprintf("%s: %v", TaskDispatchFailed, err)))
		return
	}

	c.JSON(http.StatusOK, util.OK(taskID))
}

// ListTaskExecutions 查询任务执行记录列表
// @Summary 查询任务执行记录
// @Description 分页查询任务执行记录，支持按状态和任务类型筛选，需要管理员权限
// @Tags admin
// @Produce json
// @Security SessionCookie
// @Param status query string false "状态筛选 (pending/running/succeeded/failed)"
// @Param task_type query string false "任务类型筛选"
// @Param page query int false "页码" default(1)
// @Param page_size query int false "每页条数" default(20)
// @Success 200 {object} util.ResponseAny{data=object} "任务执行记录列表"
// @Failure 401 {object} util.ResponseAny "未登录"
// @Failure 403 {object} util.ResponseAny "无管理员权限"
// @Router /api/v1/admin/tasks/executions [get]
func ListTaskExecutions(c *gin.Context) {
	var req model.ListTaskExecutionsRequest
	if err := c.ShouldBindQuery(&req); err != nil {
		c.JSON(http.StatusBadRequest, util.Err(err.Error()))
		return
	}

	executions, total, err := model.ListTaskExecutions(c.Request.Context(), req)
	if err != nil {
		c.JSON(http.StatusInternalServerError, util.Err(err.Error()))
		return
	}

	c.JSON(http.StatusOK, util.OK(gin.H{
		"items":     executions,
		"total":     total,
		"page":      req.Page,
		"page_size": req.PageSize,
	}))
}

// GetTaskExecution 查询单条任务执行详情
// @Summary 查询任务执行详情
// @Description 根据 ID 查询任务执行记录详情，包含完整执行日志，需要管理员权限
// @Tags admin
// @Produce json
// @Security SessionCookie
// @Param id path int true "任务执行记录 ID"
// @Success 200 {object} util.ResponseAny{data=model.TaskExecution} "任务执行详情"
// @Failure 400 {object} util.ResponseAny "参数错误"
// @Failure 401 {object} util.ResponseAny "未登录"
// @Failure 403 {object} util.ResponseAny "无管理员权限"
// @Failure 404 {object} util.ResponseAny "记录不存在"
// @Router /api/v1/admin/tasks/executions/{id} [get]
func GetTaskExecution(c *gin.Context) {
	id, err := strconv.ParseUint(c.Param("id"), 10, 64)
	if err != nil {
		c.JSON(http.StatusBadRequest, util.Err(admin.InvalidTaskExecutionID))
		return
	}

	execution, err := model.GetTaskExecutionByID(c.Request.Context(), id)
	if err != nil {
		c.JSON(http.StatusNotFound, util.Err(TaskNotFound))
		return
	}

	c.JSON(http.StatusOK, util.OK(execution))
}

// RetryTask 重试失败的任务
// @Summary 重试失败任务
// @Description 重新下发一条失败的任务，创建新的执行记录，需要管理员权限
// @Tags admin
// @Produce json
// @Security SessionCookie
// @Param id path int true "任务执行记录 ID"
// @Success 200 {object} util.ResponseAny{data=string} "新任务的 TaskID"
// @Failure 400 {object} util.ResponseAny "任务不支持重试或参数错误"
// @Failure 401 {object} util.ResponseAny "未登录"
// @Failure 403 {object} util.ResponseAny "无管理员权限"
// @Failure 404 {object} util.ResponseAny "记录不存在"
// @Failure 500 {object} util.ResponseAny "重试失败"
// @Router /api/v1/admin/tasks/executions/{id}/retry [post]
func RetryTask(c *gin.Context) {
	id, err := strconv.ParseUint(c.Param("id"), 10, 64)
	if err != nil {
		c.JSON(http.StatusBadRequest, util.Err(admin.InvalidTaskExecutionID))
		return
	}

	newTaskID, err := task.RetryTask(c.Request.Context(), id)
	if err != nil {
		errMsg := err.Error()
		switch {
		case strings.Contains(errMsg, "不存在"):
			c.JSON(http.StatusNotFound, util.Err(errMsg))
		case strings.Contains(errMsg, "只有失败") || strings.Contains(errMsg, "不支持重试") || strings.Contains(errMsg, "已达到最大重试"):
			c.JSON(http.StatusBadRequest, util.Err(errMsg))
		default:
			c.JSON(http.StatusInternalServerError, util.Err(fmt.Sprintf("%s: %v", TaskRetryFailed, err)))
		}
		return
	}

	c.JSON(http.StatusOK, util.OK(newTaskID))
}