MapComplete/src/UI/History/HistoryUtils.ts

import * as all_layers from "../../../public/assets/generated/themes/personal.json"
import ThemeConfig from "../../Models/ThemeConfig/ThemeConfig"
import { OsmObject } from "../../Logic/Osm/OsmObject"

export class HistoryUtils {
    public static readonly personalTheme = new ThemeConfig(<any>all_layers, true)
    private static ignoredLayers = new Set<string>(["fixme"])
    public static determineLayer(properties: Record<string, string>) {
        return this.personalTheme.getMatchingLayer(properties, this.ignoredLayers)
    }

    public static tagHistoryDiff(
        step: OsmObject,
        history: OsmObject[]
    ): {
        key: string
        value?: string
        oldValue?: string
        step: OsmObject
    }[] {
        const previous = history[step.version - 2]
        if (!previous) {
            return Object.keys(step.tags)
                .filter((key) => !key.startsWith("_") && key !== "id")
                .map((key) => ({
                    key,
                    value: step.tags[key],
                    step,
                }))
        }
        const previousTags = previous.tags
        return Object.keys(step.tags)
            .filter((key) => !key.startsWith("_"))
            .map((key) => {
                const value = step.tags[key]
                const oldValue = previousTags[key]
                return {
                    key,
                    value,
                    oldValue,
                    step,
                }
            })
            .filter((ch) => ch.oldValue !== ch.value)
    }

    public static fullHistoryDiff(
        histories: OsmObject[][],
        onlyShowUsername?: Set<string>
    ): {
        key: string
        value?: string
        oldValue?: string
        step: OsmObject
    }[] {
        const allDiffs: {
            key: string
            value?: string
            oldValue?: string
            step: OsmObject
        }[] = []
        for (const history of histories) {
            const filtered = history.filter(
                (step) =>
                    !onlyShowUsername || onlyShowUsername?.has(step.tags["_last_edit:contributor"])
            )
            for (const step of filtered) {
                const diff: {
                    key: string
                    value?: string
                    oldValue?: string
                    step: OsmObject
                }[] = HistoryUtils.tagHistoryDiff(step, history)
                allDiffs.push(...diff)
            }
        }

        return allDiffs
    }
}