// Copyright (C) NHR@FAU, University Erlangen-Nuremberg.
// All rights reserved. This file is part of cc-backend.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package config

import (
	"bytes"
	"encoding/json"
	"time"

	cclog "github.com/ClusterCockpit/cc-lib/ccLogger"
)

type ResampleConfig struct {
	// Array of resampling target resolutions, in seconds; Example: [600,300,60]
	Resolutions []int `json:"resolutions"`
	// Trigger next zoom level at less than this many visible datapoints
	Trigger int `json:"trigger"`
}

// Format of the configuration (file). See below for the defaults.
type ProgramConfig struct {
	// Address where the http (or https) server will listen on (for example: 'localhost:80').
	Addr string `json:"addr"`

	// Addresses from which secured admin API endpoints can be reached, can be wildcard "*"
	ApiAllowedIPs []string `json:"apiAllowedIPs"`

	// Drop root permissions once .env was read and the port was taken.
	User  string `json:"user"`
	Group string `json:"group"`

	// Disable authentication (for everything: API, Web-UI, ...)
	DisableAuthentication bool `json:"disable-authentication"`

	// If `embed-static-files` is true (default), the frontend files are directly
	// embeded into the go binary and expected to be in web/frontend. Only if
	// it is false the files in `static-files` are served instead.
	EmbedStaticFiles bool   `json:"embed-static-files"`
	StaticFiles      string `json:"static-files"`

	// 'sqlite3' or 'mysql' (mysql will work for mariadb as well)
	DBDriver string `json:"db-driver"`

	// For sqlite3 a filename, for mysql a DSN in this format: https://github.com/go-sql-driver/mysql#dsn-data-source-name (Without query parameters!).
	DB string `json:"db"`

	// Keep all metric data in the metric data repositories,
	// do not write to the job-archive.
	DisableArchive bool `json:"disable-archive"`

	EnableJobTaggers bool `json:"enable-job-taggers"`

	// Validate json input against schema
	Validate bool `json:"validate"`

	// If 0 or empty, the session does not expire!
	SessionMaxAge string `json:"session-max-age"`

	// If both those options are not empty, use HTTPS using those certificates.
	HttpsCertFile string `json:"https-cert-file"`
	HttpsKeyFile  string `json:"https-key-file"`

	// If not the empty string and `addr` does not end in ":80",
	// redirect every request incoming at port 80 to that url.
	RedirectHttpTo string `json:"redirect-http-to"`

	// If overwritten, at least all the options in the defaults below must
	// be provided! Most options here can be overwritten by the user.
	UiDefaults map[string]any `json:"ui-defaults"`

	// Where to store MachineState files
	MachineStateDir string `json:"machine-state-dir"`

	// If not zero, automatically mark jobs as stopped running X seconds longer than their walltime.
	StopJobsExceedingWalltime int `json:"stop-jobs-exceeding-walltime"`

	// Defines time X in seconds in which jobs are considered to be "short" and will be filtered in specific views.
	ShortRunningJobsDuration int `json:"short-running-jobs-duration"`

	// Energy Mix CO2 Emission Constant [g/kWh]
	// If entered, displays estimated CO2 emission for job based on jobs totalEnergy
	EmissionConstant int `json:"emission-constant"`

	// If exists, will enable dynamic zoom in frontend metric plots using the configured values
	EnableResampling *ResampleConfig `json:"resampling"`
}

type IntRange struct {
	From int `json:"from"`
	To   int `json:"to"`
}

type TimeRange struct {
	From  *time.Time `json:"from"`
	To    *time.Time `json:"to"`
	Range string     `json:"range,omitempty"`
}

type FilterRanges struct {
	Duration  *IntRange  `json:"duration"`
	NumNodes  *IntRange  `json:"numNodes"`
	StartTime *TimeRange `json:"startTime"`
}

type ClusterConfig struct {
	Name                 string          `json:"name"`
	FilterRanges         *FilterRanges   `json:"filterRanges"`
	MetricDataRepository json.RawMessage `json:"metricDataRepository"`
}

var Clusters []*ClusterConfig

var Keys ProgramConfig = ProgramConfig{
	Addr:                      "localhost:8080",
	DisableAuthentication:     false,
	EmbedStaticFiles:          true,
	DBDriver:                  "sqlite3",
	DB:                        "./var/job.db",
	DisableArchive:            false,
	Validate:                  false,
	SessionMaxAge:             "168h",
	StopJobsExceedingWalltime: 0,
	ShortRunningJobsDuration:  5 * 60,
	UiDefaults: map[string]any{
		"analysis_view_histogramMetrics":         []string{"flops_any", "mem_bw", "mem_used"},
		"analysis_view_scatterPlotMetrics":       [][]string{{"flops_any", "mem_bw"}, {"flops_any", "cpu_load"}, {"cpu_load", "mem_bw"}},
		"job_view_nodestats_selectedMetrics":     []string{"flops_any", "mem_bw", "mem_used"},
		"job_view_selectedMetrics":               []string{"flops_any", "mem_bw", "mem_used"},
		"job_view_showFootprint":                 true,
		"job_list_usePaging":                     false,
		"plot_general_colorBackground":           true,
		"plot_general_colorscheme":               []string{"#00bfff", "#0000ff", "#ff00ff", "#ff0000", "#ff8000", "#ffff00", "#80ff00"},
		"plot_general_lineWidth":                 3,
		"plot_list_jobsPerPage":                  50,
		"plot_list_selectedMetrics":              []string{"cpu_load", "mem_used", "flops_any", "mem_bw"},
		"plot_view_plotsPerRow":                  3,
		"plot_view_showPolarplot":                true,
		"plot_view_showRoofline":                 true,
		"plot_view_showStatTable":                true,
		"system_view_selectedMetric":             "cpu_load",
		"analysis_view_selectedTopEntity":        "user",
		"analysis_view_selectedTopCategory":      "totalWalltime",
		"status_view_selectedTopUserCategory":    "totalJobs",
		"status_view_selectedTopProjectCategory": "totalJobs",
	},
}

func Init(mainConfig json.RawMessage, clusterConfig json.RawMessage) {
	Validate(configSchema, mainConfig)
	dec := json.NewDecoder(bytes.NewReader(mainConfig))
	dec.DisallowUnknownFields()
	if err := dec.Decode(&Keys); err != nil {
		cclog.Abortf("Config Init: Could not decode config file '%s'.\nError: %s\n", mainConfig, err.Error())
	}

	Validate(clustersSchema, clusterConfig)
	dec = json.NewDecoder(bytes.NewReader(clusterConfig))
	dec.DisallowUnknownFields()
	if err := dec.Decode(&Clusters); err != nil {
		cclog.Abortf("Config Init: Could not decode config file '%s'.\nError: %s\n", mainConfig, err.Error())
	}

	if Clusters == nil || len(Clusters) < 1 {
		cclog.Abort("Config Init: At least one cluster required in config. Exited with error.")
	}
}