// SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Commercial
// SPDX-FileCopyrightText: 2025-2026 Christian Galo

package server

import (
	"html/template"
	"strconv"

	"git.coopcloud.tech/wiki-cafe/member-console/internal/config"
	"git.coopcloud.tech/wiki-cafe/member-console/internal/forms"
)

// The integration settings form (spec integration-settings "Operator
// settings surface is generic and declaration-driven"; spec form-library;
// design D9, D21; findings FA-10, FA-24). One form covers every key an
// installed integration declares, so a refusal for any key answers 422
// with that field's reason under its control, exactly like every other
// form on either surface; a refusal that belongs to no field (the key is
// unknown, or the write itself fails) lands in the form-level slot.
//
// The Table family is the only one a Settings form may declare (design
// D21): one row per key, the key and its usage in the first column, the
// effective value and the winning source in the page's own cells, the
// control last, and one Save below the table. Round 3 forced this into
// Stacked, and the page lost the effective value, the source and the
// status it had carried, gained "(optional)" on every row, showed "None"
// in the control with the real value in a hint, and kept a second table
// below the form for the secret keys (maintainer, 2026-09-04).
//
// This file is the form's home; the registry is only the index (design
// D1). It sits beside operator_integration_settings.go, which parses
// through the declaration and never through r.FormValue.

// integrationSettingsFormName is the declaration's name and its data-form
// id, the same on every integration's settings page: one form, rendered
// once per installed integration with a different field list each time.
const integrationSettingsFormName = "operator.integration.settings"

// integrationSettingsForm is the registered declaration. It carries the
// contract every integration's settings page shares (kind, family, method,
// path, columns, commit) for the registry, the invariants test, the route
// test and the design system's registered-forms table; it is never
// rendered as-is. The real field list cannot be fixed here: each installed
// integration declares its own ConfigSpec, assembled by the composition
// root when the server starts, after this package's init has already run
// and registered this declaration, and a settings page with no
// per-integration template or handler edits must show whichever keys that
// integration happens to declare (integration-settings, "New integration
// needs no surface work"). settingsFormFor builds the per-request
// declaration those pages actually render, from the same name, kind,
// family, method, path, columns and commit.
var integrationSettingsForm = forms.Register(forms.FormSpec{
	Name:          integrationSettingsFormName,
	Kind:          forms.KindSettings,
	Family:        forms.Table,
	Method:        "POST",
	Path:          "/operator/integrations/{integrationKey}/settings",
	Target:        "#operator-body",
	Swap:          "innerHTML",
	LabelColumn:   "Key",
	ControlColumn: "Override",
	Columns:       []string{"Effective value", "Source"},
	Fields: []forms.Field{
		{
			Name:         "override",
			Label:        "override",
			Control:      forms.Text,
			Optional:     true,
			Autocomplete: "off",
			Hint:         "One row per configuration key the installed integration declares.",
		},
	},
	Commit: "Save",
})

// settingsFormFor is the settings page's real declaration for one request:
// the registered spec's name, kind, family, route, columns and commit,
// with one row per declared key, in the order the integration declared
// them. Every control sets a value and does nothing else (design D21 round
// 5): an enum key's select offers its declared members and no empty
// choice, a bool key is a checkbox, and a text or list key is a text
// control. Removing a stored override is the row's own Clear action, not a
// value the control can carry. A secret key is a static row: it states
// where the value is set and offers no control, because there is nothing
// an operator can set here (design D21, which is why the separate secrets
// table below the form is gone).
func settingsFormFor(rows []SettingRow) forms.FormSpec {
	spec := integrationSettingsForm
	spec.Fields = nil
	for _, row := range rows {
		spec.Fields = append(spec.Fields, settingsField(row))
	}
	return spec
}

// settingsField declares one key's row. The control is bound to the value
// in force (settingsValues): the stored override when one exists, the
// boot-effective value otherwise, so the control says what is actually
// running (design D21).
//
// A bool key is a checkbox, not a three-way select: a boolean has two
// states, and the select's third choice offered a way to submit nothing at
// all (maintainer, 2026-09-05: "fedwiki-sync-enabled is also odd"). The
// table places the label itself, in the label column, so the control cell
// holds the input alone and no second label is rendered.
//
// A text control's Placeholder is its type's format example
// (row.Placeholder, set by settingsPlaceholder from the key's declared or
// inferred type; design D4, typed-config-keys), shown only once the
// control is empty; a bare string key carries none.
func settingsField(row SettingRow) forms.Field {
	if row.Secret {
		return forms.Field{
			Name:    row.Key,
			Label:   row.Key,
			Control: forms.Static,
			Value:   "Set " + row.Key + " (or " + row.Key + "-file) in the environment.",
			Hint:    row.Usage,
		}
	}
	f := forms.Field{
		Name:         row.Key,
		Label:        row.Key,
		Control:      forms.Text,
		Optional:     true,
		Autocomplete: "off",
		Hint:         settingsHint(row),
		Placeholder:  row.Placeholder,
	}
	switch row.Kind {
	case "enum":
		f.Control = forms.Select
		for _, v := range row.Enum {
			f.Options = append(f.Options, forms.Option{Value: v, Label: v})
		}
	case "bool":
		f.Control = forms.Checkbox
		// A checkbox submits "true" when ticked and nothing when it is not;
		// autocomplete has no meaning on one and the part never emits it
		// there.
		f.Autocomplete = ""
	case "list":
		f.Help = forms.Help("List format", "Comma-separated list.")
	}
	return f
}

// settingsHint is the key's declared usage, and, for the rare key whose
// value has a real-world consequence beyond this deployment's own state,
// that consequence too. The effective value is a column now,
// and the pending-restart state is a badge in it, so neither is repeated
// here (design D21: "the Effective column carries the fact").
func settingsHint(row SettingRow) string {
	return appendSentence(row.Usage, row.Warning)
}

// appendSentence joins two sentence fragments with a space, skipping either
// side that is empty.
func appendSentence(hint, addition string) string {
	if hint == "" {
		return addition
	}
	if addition == "" {
		return hint
	}
	return hint + " " + addition
}

// settingsBoundValue is the value a key's control renders with, and the
// value a submission is compared against to decide whether anything
// changed: the stored override when one exists, the boot-effective value
// otherwise (design D21's control-shows-the-value-in-force rule, and its
// handler no-change rule, which are the same fact read twice).
func settingsBoundValue(row SettingRow) string {
	value := row.Effective
	if row.HasOverride {
		value = row.Override
	}
	if row.Kind == "bool" {
		// A checkbox is ticked or it is not, so a bool row's value in force
		// is one of two strings: anything that is not "true" is false. This
		// is the same reduction the control renders with, so the state on
		// the page and the state a submission is compared against cannot
		// disagree.
		return strconv.FormatBool(value == "true")
	}
	return value
}

// settingsEmptyRefusal is what a text or list control emptied against a
// value that was there is told. Both messages carry the fact the person
// needs and nothing else: where a stored override is what they emptied,
// the way to remove it is the row's Clear, and that is not something the
// page states anywhere else (design D21 round 5).
func settingsEmptyRefusal(row SettingRow) string {
	if row.HasOverride {
		return "Enter a value, or clear the override."
	}
	return "Enter a value."
}

// settingsSubmittedValue is what one row's control sent, in the display
// form settingsBoundValue produces: a checkbox missing from the body is
// "false", every other control is its raw text.
func settingsSubmittedValue(values forms.Values, row SettingRow) string {
	if row.Kind == "bool" {
		return strconv.FormatBool(values.Bool(row.Key))
	}
	return values.String(row.Key)
}

// settingsValues binds each row's control to the value in force, so a
// select shows the running value, a checkbox stands in its running state,
// and a text control shows the running text rather than an empty box
// (design D5, "bound to a record").
func settingsValues(rows []SettingRow) forms.Values {
	values := forms.NewValues()
	for _, row := range rows {
		if row.Secret {
			continue
		}
		values.Set(row.Key, settingsBoundValue(row))
	}
	return values
}

// settingsCells renders each row's Effective value and Source cells, in the
// declaration's Columns order. Each cell holds its own subject alone
// (design D9): the Effective cell the value in force, the Source cell its
// badge, and nothing that describes the stored override; that renders in
// the Override cell instead (settingsControlFooters). The badges are the
// page's, not the library's, which is why they arrive pre-rendered (design
// D21); they go through the same statusBadge part every other surface
// uses, from the settings template's own cell defines, so no badge markup
// is written in Go.
func settingsCells(t *SafeTemplates, rows []SettingRow) map[string][]template.HTML {
	if t == nil {
		return nil
	}
	cells := make(map[string][]template.HTML, len(rows))
	for _, row := range rows {
		cells[row.Key] = []template.HTML{
			t.Fragment("settingsEffectiveCell", row),
			t.Fragment("settingsSourceCell", row),
		}
	}
	return cells
}

// settingsControlFooters renders each row's Override cell content under
// its control: Clear when a stored override exists, and the Pending
// restart badge when the stored state differs from the running one, both
// on one line (design D9, typed-config-keys): everything that describes
// the stored override rather than the running value, kept out of the
// Effective and Source cells settingsCells renders. Empty (renders
// nothing) for a row with neither.
func settingsControlFooters(t *SafeTemplates, rows []SettingRow) map[string]template.HTML {
	if t == nil {
		return nil
	}
	footers := make(map[string]template.HTML, len(rows))
	for _, row := range rows {
		footers[row.Key] = t.Fragment("settingsOverrideCell", row)
	}
	return footers
}

// findConfigKey returns the declared key named name, and whether it exists.
func findConfigKey(keys []config.ConfigKey, name string) (config.ConfigKey, bool) {
	for _, k := range keys {
		if k.Name == name {
			return k, true
		}
	}
	return config.ConfigKey{}, false
}